Red Hat JBoss Fuse

Apache Camel Component Reference

Quickly find the settings for all of the components

Version 6.1

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  • JLine (http://jline.sourceforge.net) jline:jline:jar:1.0
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24 Feb 2015

Abstract

Apache Camel has over 100 components and each component is highly configurable. This guide describes the settings for each of the components.
1. Components Overview
1.1. List of Components
2. ActiveMQ
3. AHC
4. AMQP
5. APNS
6. Atom
7. avro
8. AWS
8.1. Introduction to the AWS Components
8.2. AWS-CW
8.3. AWS-DDB
8.4. AWS-S3
8.5. AWS-SDB
8.6. AWS-SES
8.7. AWS-SNS
8.8. AWS-SQS
9. Bean
10. Bean Validation
11. Browse
12. Cache
12.1. Cache Component
12.2. cacheReplicationJMSExample
13. CDI
14. Class
15. CMIS
16. Cometd
17. Context
18. ControlBus Component
19. CouchDB
20. Crypto (Digital Signatures)
21. CXF
22. CXF Bean Component
23. CXFRS
24. DataFormat Component
25. DataSet
26. Direct
27. Direct-VM
28. Disruptor
29. DNS
30. EJB
31. ElasticSearch
32. EventAdmin
33. Exec
34. Fabric Component
35. Facebook
36. File2
37. Flatpack
38. FOP
39. FreeMarker
40. FTP2
41. GAE
41.1. Introduction to the GAE Components
41.2. gauth
41.3. ghttp
41.4. glogin
41.5. gmail
41.6. gsec
41.7. gtask
42. Geocoder
43. Guava EventBus
44. HawtDB
45. Hazelcast Component
46. hbase
47. HDFS
48. HL7
49. HTTP
50. HTTP4
51. iBATIS
52. IRC
53. Jasypt
54. JavaSpace
55. JBI
55.1. JBI Component
55.2. JBI Service Unit Archetype
56. jclouds
57. JCR
58. JDBC
59. Jetty
60. Jing
61. JMS
62. JMX
63. JPA
64. Jsch
65. JT400
66. Kestrel
67. Krati
68. Language
69. LDAP
70. LevelDB
71. List
72. Log
73. Lucene
74. Mail
75. Master Component
76. MINA [Deprecated]
77. MINA2 [Deprecated]
78. Mock
79. MongoDB
80. MQTT
81. MSV
82. Mustache
83. MVEL Component
84. MyBatis
85. Nagios
86. Netty
87. Netty HTTP
88. NMR
89. Pax-Logging
90. Printer
91. Properties
92. Quartz
93. Quartz2
94. Quickfix
95. RabbitMQ
96. Ref
97. Restlet
98. RMI
99. Routebox
100. RSS
101. Salesforce
102. SAP Component
102.1. Overview
102.2. Message Body
102.3. Configuration Overview
102.4. Destination Configuration
102.5. Server Configuration
102.6. Repository Configuration
102.7. Transaction Support
102.8. XML Serialization
102.9. Example 1: Reading Data from SAP
102.10. Example 2: Writing Data to SAP
102.11. Example 3: Handling Requests from SAP
103. SAP NetWeaver
104. SEDA
105. SERVLET
106. ServletListener Component
107. Shiro Security
108. Sip
109. SJMS
110. SMPP
111. SNMP
112. Solr
113. SpringBatch
114. SpringIntegration
115. Spring Event
116. Spring LDAP
117. Spring Redis
118. Spring Security
119. Spring Web Services
120. SQL Component
121. SSH
122. StAX
123. Stomp
124. Stream
125. StringTemplate
126. Stub
127. Test
128. Timer
129. Twitter
130. UrlRewrite
131. Validation
132. Velocity
133. Vertx
134. VM
135. Weather
136. Websocket
137. XmlRpc
138. XML Security component
139. XMPP
140. XQuery Endpoint
141. XSLT
142. Yammer
143. Zookeeper

Chapter 1. Components Overview

Abstract

This chapter provides a summary of all the components available for Apache Camel.

1.1. List of Components

Table of components

The following components are available for use with Apache Camel.

Table 1.1. Apache Camel Components

Component Endpoint URI Artifact ID Description
ActiveMQ activemq:[queue:|topic:]DestinationName activemq-core For JMS Messaging with Apache ActiveMQ.
AHC ahc:http[s]://Hostname[:Port][/ResourceUri] camel-ahc To call external HTTP services using Async Http Client
AMQP amqp:[queue:|topic:]DestinationName[?Options]] camel-amqp For messaging with the AMQP protocol.
APNS
apns:notify[?Options]
apns:consumer[?Options]
camel-apns For sending notifications to Apple iOS devices.
Atom atom://AtomUri[?Options] camel-atom Working with Apache Abdera for atom integration, such as consuming an atom feed.
Avro avro:http://Hostname[:Port][?Options] camel-avro Working with Apache Avro for data serialization.
AWS-CW aws-cw://Namespace[?Options] camel-aws For sending metrics to Amazon CloudWatch.
AWS-DDB aws-ddb://TableName[?Options] camel-aws For working with Amazon's DynamoDB (DDB).
AWS-SDB aws-sdb://DomainName[?Options] camel-aws For working with Amazon's SimpleDB (SDB).
AWS-SES aws-ses://From[?Options] camel-aws For working with Amazon's Simple Email Service (SES).
AWS-S3 aws-s3://BucketName[?Options] camel-aws For working with Amazon's Simple Storage Service (S3).
AWS-SNS aws-sns://TopicName[?Options] camel-aws For Messaging with Amazon's Simple Notification Service (SNS).
AWS-SQS aws-sqs://QueueName[?Options] camel-aws For Messaging with Amazon's Simple Queue Service (SQS).
Bean bean:BeanID[?methodName=Method] camel-core Uses the Bean Binding to bind message exchanges to beans in the Registry. Is also used for exposing and invoking POJO (Plain Old Java Objects).
Bean Validation
bean-validator:Something[?Options]
camel-bean-validator Validates the payload of a message using the Java Validation API (JSR 303 and JAXP Validation) and its reference implementation Hibernate Validator.
Browse browse: Name camel-core Provdes a simple BrowsableEndpoint which can be useful for testing, visualisation tools or debugging. The exchanges sent to the endpoint are all available to be browsed.
Cache cache://CacheName[?Options] camel-cache The cache component enables you to perform caching operations using EHCache as the Cache Implementation.
Class class:ClassName[?method=MethodName] camel-core Uses the Bean binding to bind message exchanges to beans in the registry. Is also used for exposing and invoking POJOs (Plain Old Java Objects).
Cometd cometd://Hostname[:Port]/ChannelName[?Options] camel-cometd A transport for working with the jetty implementation of the cometd/bayeux protocol.
Context context:CamelContextId:LocalEndpointName camel-context Refers to an endpoint in a different CamelContext.
Crypto
crypto:sign:Name[?Options]
crypto:verify:Name[?Options]
camel-crypto Sign and verify exchanges using the Signature Service of the Java Cryptographic Extension.
CXF cxf://Address[?Options] camel-cxf Working with Apache CXF for web services integration.
CXF Bean cxf:BeanName camel-cxf Proceess the exchange using a JAX WS or JAX RS annotated bean from the registry.
CXFRS cxfrs:bean:RsEndpoint[?Options] camel-cxf Provides integration with Apache CXF for connecting to JAX-RS services hosted in CXF.
DataFormat dataformat:Name:(marshal|unmarshal)[?Options] camel-core Enables you to marshal or unmarshal a message in one of the standard Camel data formats, by sending it to an endpoint.
DataSet dataset:Name[?Options] camel-core For load & soak testing the DataSet provides a way to create huge numbers of messages for sending to Components or asserting that they are consumed correctly.
Direct direct:EndpointID[?Options] camel-core Synchronous call (single-threaded) to another endpoint from same CamelContext.
Direct-VM direct-vm:EndpointID[?Options] camel-core Synchronous call (single-threaded) to another endpoint in another CamelContext running in the same JVM.
Disruptor
disruptor:Name[?Options]
disruptor-vm:Name[?Options]
camel-disruptor Similar to a SEDA endpoint, but uses a Disruptor instead of a blocking queue.
DNS dns:Operation camel-dns Look up domain information and run DNS queries using DNSJava
EJB ejb:EjbName[?method=MethodName] camel-ejb Uses the Bean binding to bind message exchanges to EJBs. It works like the Bean component, but just for accessing EJBs. Supports EJB 3.0 onwards.
EventAdmin eventadmin:topic camel-eventadmin
Exec exec://Executable[?Options] camel-exec Execute system command.
Fabric fabric:ClusterID[:PublishedURI][?Options] fabric-camel Look up or publish a fabric endpoint.
Facebook facebook://[Endpoint][?Options] camel-facebook Provides access to all of the Facebook APIs accessible using Facebook4J.
File2 file://DirectoryName[?Options] camel-core Sending messages to a file or polling a file or directory.
Flatpack flatpack:[fixed|delim]: ConfigFile camel-flatpack Processing fixed width or delimited files or messages using the FlatPack library
FOP fop:OutputFormat camel-fop Renders the message into different output formats using Apache FOP.
Freemarker freemarker: TemplateResource camel-freemarker Generates a response using a Freemarker template.
FTP2 ftp://[Username@]Hostname[:Port]/Directoryname[?Options] camel-ftp Sending and receiving files over FTP.
GAuth gauth://Name[?Options] camel-gae Used by web applications to implement a Google-specific OAuth consumer
GHTTP
ghttp:///Path[?Options]
ghttp://Hostname[:Port]/Path[?Options]
ghttps://Hostname[:Port]/Path[?Options]
camel-gae Provides connectivity to the GAE URL fetch service and can also be used to receive messages from servlets.
GLogin glogin://Hostname[:Port][?Options] camel-gae Used by Camel applications outside Google App Engine (GAE) for programmatic login to GAE applications.
GMail
gmail://Username@gmail.com[?Options]
gmail://Username@googlemail.com[?Options]
camel-gae Supports sending of emails via the GAE mail service.
GTask gtask://QueueName camel-gae Supports asynchronous message processing on GAE using the task queueing service as a message queue.
Geocoder
geocoder:Address:Name[?Options]
geocoder:latlng:Latitude,Longitude[?Options]
camel-geocoder Looks up geocodes (latitude and longitude) for a given address, or performs reverse look-up.
Guava EventBus guava-eventbus:BusName[?EventClass=ClassName] camel-guava-eventbus The Google Guava EventBus allows publish-subscribe-style communication between components without requiring the components to explicitly register with one another (and thus be aware of each other). This component provides integration bridge between Camel and Google Guava EventBus infrastructure.
Hazelcast hazelcast://StoreType:CacheName[?Options] camel-hazelcast Hazelcast is a data grid entirely implemented in Java (single JAR). This component supports map, multimap, seda, queue, set, atomic number and simple cluster.
HBase hbase://Table[?Options] camel-hbase For reading/writing from/to an HBase store (Hadoop database).
HDFS hdfs://Path[?Options] camel-hdfs For reading/writing from/to an HDFS filesystem.
HL7 mina:tcp://Host[:Port] camel-hl7 For working with the HL7 MLLP protocol and the HL7 model using the HAPI library.
HTTP http://Hostname[:Port][/ResourceUri] camel-http For calling out to external HTTP servers, using Apache HTTP Client 3.x.
HTTP4 http://Hostname[:Port][/ResourceUri] camel-http4 For calling out to external HTTP servers, using Apache HTTP Client 4.x.
iBATIS ibatis:OperationName[?Options] camel-ibatis Performs a query, poll, insert, update or delete in a relational database using Apache iBATIS.
IMap imap://[UserName@]Host[:Port][?Options] camel-mail Receiving email using IMap.
IRC irc:Host[:Port]/#Room camel-irc For IRC communication.
JavaSpace javaspace:jini://Host[?Options] camel-javaspace Sending and receiving messages through JavaSpace.
JBI
jbi:service:serviceNamespace[sep]serviceName
jbi:endpoint:serviceNamespace[sep]serviceName[sep]endpointName
jbi:name:endpointName
camel-jbi For JBI integration such as working with Apache ServiceMix.
JClouds jclouds:[Blobstore|ComputService]:Provider camel-jclouds For interacting with cloud compute & blobstore service via JClouds.
JCR jcr://UserName:Password@Repository/path/to/node camel-jcr Storing a message in a JCR (JSR-170) compliant repository like Apache Jackrabbit.
JDBC jdbc:DataSourceName[?Options] camel-jdbc For performing JDBC queries and operations.
Jetty jetty:http://Host[:Port][/ResourceUri] camel-jetty For exposing services over HTTP.
Jing
rng:LocalOrRemoteResource
rnc:LocalOrRemoteResource
camel-jing Validates the payload of a message using RelaxNG or RelaxNG compact syntax.
JMS jms:[temp:][queue:|topic:]DestinationName[?Options] camel-jms Working with JMS providers.
JMX jmx://Platform[?Options] camel-jmx For working with JMX notification listeners.
JPA jpa:[EntityClassName][?Options] camel-jpa For using a database as a queue via the JPA specification for working with OpenJPA, Hibernate or TopLink.
Jsch scp://Hostname/Destination camel-jsch Support for the scp protocol.
JT400 jt400://User:Pwd@System/PathToDTAQ camel-jt400 For integrating with data queues on an AS/400 (aka System i, IBM i, i5, ...) system.
Kestrel kestrel://[AddressList/]Queuename[?Options] camel-kestrel For producing to or consuming from Kestrel queues.
Krati krati://[PathToDatastore/][?Options] camel-krati For producing to or consuming to Krati datastores.
Language language://LanguageName[:Script][?Options] camel-core Executes language scripts.
LDAP ldap:Host[:Port]?base=...[&scope=Scope] camel-ldap Performing searches on LDAP servers (Scope must be one of object|onelevel|subtree).
LevelDB N/A camel-leveldb A very lightweight and embeddable key-value database.
List list:ListID camel-core Provides a simple BrowsableEndpoint which can be useful for testing, visualisation tools or debugging. The exchanges sent to the endpoint are all available to be browsed.
Log log:LoggingCategory[?level=LoggingLevel] camel-core Uses Jakarta Commons Logging to log the message exchange to some underlying logging system like log4j.
Lucene
lucene:SearcherName:insert[?analyzer=Analyzer]
lucene:SearcherName:query[?analyzer=Analyzer]
camel-lucene Uses Apache Lucene to perform Java-based indexing and full text based searches using advanced analysis/tokenization capabilities.
Master REVISIT
MINA
mina:tcp://Hostname[:Port][?Options]
mina:udp://Hostname[:Port][?Options]
mina:multicast://Hostname[:Port][?Options]
mina:vm://Hostname[:Port][?Options]
camel-mina Working with Apache MINA.
MINA2
mina2:tcp://Hostname[:Port][?Options]
mina2:udp://Hostname[:Port][?Options]
mina2:vm://Hostname[:Port][?Options]
camel-mina2 Working with Apache MINA 2.x.
Mock mock:EndpointID camel-core For testing routes and mediation rules using mocks.
MongoDB mongodb:Connection[?Options] camel-mongodb Interacts with MongoDB databases and collections. Offers producer endpoints to perform CRUD-style operations and more against databases and collections, as well as consumer endpoints to listen on collections and dispatch objects to Camel routes.
MQTT mqtt:Name camel-mqtt Component for communicating with MQTT M2M message brokers
MSV msv:LocalOrRemoteResource camel-msv Validates the payload of a message using the MSV Library.
Mustache mustache:TemplateName[?Options] camel-mustache Enables you to process a message using a Mustache template.
MVEL mvel:TemplateName[?Options] camel-mvel Enables you to process a message using an MVEL template.
MyBatis mybatis:StatementName camel-mybatis Performs a query, poll, insert, update or delete in a relational database using MyBatis.
Nagios nagios://Host[:Port][?Options] camel-nagios Sending passive checks to Nagios using JSendNSCA.
Netty
netty:tcp://localhost:99999[?Options]
netty:udp://Remotehost:99999/[?Options]
camel-netty Working with TCP and UDP protocols using Java NIO based capabilities offered by the JBoss Netty community project.
Netty HTTP netty-http:http://Hostname[:Port][?Options] camel-netty-http An extension to the Netty component, facilitating the HTTP transport.
NMR nmr:serviceMixURI servicemix-camel For OSGi integration when working with Red Hat JBoss Fuse. Enables you to specify the URI of a ServiceMix endpoint.
Pax-Logging paxlogging:Appender camel-paxlogging
POP pop3://[UserName@]Host[:Port][?Options] camel-mail Receiving email using POP3 and JavaMail.
Printer
lpr://localhost[:Port]/default[?Options]
lpr://RemoteHost[:Port]/path/to/printer[?Options]
camel-printer Provides a way to direct payloads on a route to a printer.
Properties properties://Key[?Options] camel-properties Facilitates using property placeholders directly in endpoint URI definitions.
Quartz
quartz://[GroupName/]TimerName[?Options]
quartz://GroupName/TimerName/CronExpression
camel-quartz Provides a scheduled delivery of messages using the Quartz scheduler.
Quartz2
quartz2://[GroupName/]TimerName[?Options]
quartz2://GroupName/TimerName/CronExpression
camel-quartz2 Provides a scheduled delivery of messages using the Quartz Scheduler 2.x.
Quickfix
quickfix-server:ConfigFile
quickfix-client:ConfigFile
camel-quickfix Implementation of the QuickFix for Java engine which allow to send/receive FIX messages.
RabbitMQ rabbitmq://Hostname[:Port]/ExchangeName[?Options] camel-rabbitmq Enables you to produce and consume messages from a RabbitMQ instance.
Ref ref:EndpointID camel-core Component for lookup of existing endpoints bound in the Registry.
Restlet restlet:RestletUrl[?Options] camel-restlet Component for consuming and producing Restful resources using Restlet.
RMI rmi://RmiRegistryHost:RmiRegistryPort/RegistryPath camel-rmi Working with RMI.
Routebox routebox:routeboxName[?Options] camel-routebox
RSS rss:Uri camel-rss Working with ROME for RSS integration, such as consuming an RSS feed.
RNC rnc:LocalOrRemoteResource camel-jing Validates the payload of a message using RelaxNG Compact Syntax.
RNG rng:LocalOrRemoteResource camel-jing Validates the payload of a message using RelaxNG.
Salesforce salesforce:Topic[?Options] camel-salesforce Enables producer and consumer endpoints to communicate with Salesforce using Java DTOs.
SAP sap:[destination:DestinationName|server:ServerName]rfcName[?Options] camel-sap Enables outbound and inbound communication to and from SAP systems using synchronous remote function calls, sRFC.
Chapter 103, SAP NetWeaver sap-netweaver:https://Hostname[:Port]/Path[?Options] camel-sap-netweaver Integrates with the SAP NetWeaver Gateway using HTTP transports.
Scalate scalate:TemplateName[?Options] org.fusesource.scalate/scalate-camel Uses the given Scalate template to transform the message.
SEDA seda:EndpointID camel-core Used to deliver messages to a java.util.concurrent.BlockingQueue, useful when creating SEDA style processing pipelines within the same CamelContext.
SERVLET servlet://RelativePath[?Options] camel-servlet Provides HTTP based endpoints for consuming HTTP requests that arrive at a HTTP endpoint and this endpoint is bound to a published Servlet.
ServletListener N/A camel-servletlistener Used for bootstrapping Camel applications in Web applications.
SFTP sftp://[Username@]Hostname[:Port]/Directoryname[?Options] camel-ftp Sending and receiving files over SFTP.
Sip
sip://User@Hostname[:Port][?Options]
sips://User@Hostname[:Port][?Options]
camel-sip Publish/subscribe communication capability using the telecom SIP protocol. RFC3903 - Session Initiation Protocol (SIP) Extension for Event
SJMS sjms:[queue:|topic:]destinationName[?Options] camel-sjms A JMS client for Camel that employs best practices for JMS client creation and configuration.
SMPP smpp://UserInfo@Host[:Port][?Options] camel-smpp To send and receive SMS using Short Messaging Service Center using the JSMPP library.
SMTP smtp://[UserName@]Host[:Port][?Options] camel-mail Sending email using SMTP and JavaMail.
SNMP snmp://Hostname[:Port][?Options] camel-snmp Gives you the ability to poll SNMP capable devices or receive traps.
Solr solr://Hostname[:Port]/Solr[?Options] camel-solr Uses the Solrj client API to interface with an Apache Lucene Solr server.
Spring Batch spring-batch:Job[?Options] camel-spring-batch To bridge Camel and Spring Batch.
Spring Event spring-event://dummy camel-spring Working with Spring ApplicationEvents.
Spring Integration spring-integration:DefaultChannelName[?Options] camel-spring-integration The bridge component of Camel and Spring Integration.
Spring LDAP spring-ldap:SpringLdapTemplate[?Options] camel-spring-ldap Provides a Camel wrapper for Spring LDAP.
Spring Redis spring-redis://Hostname[:Port][?Options] camel-spring-redis Enables sending and receiving messages from Redis, which is an advanced key-value store, where keys can contain strings, hashes, lists, sets and sorted sets.
Spring Web Services spring-ws:[MappingType:]Address[?Options] camel-spring-ws Client-side support for accessing web services, and server-side support for creating your own contract-first web services using Spring Web Services.
SQL sql:SqlQueryString[?Options] camel-sql Performing SQL queries using JDBC.
SSH ssh:[Username[:Password]@]Host[:Port][?Options] camel-ssh For sending commands to a SSH server.
StAX stax:ContentHandlerClassName camel-stax Process messages through a SAX ContentHandler.
Stomp stomp:queue:Destination[?Options] camel-stomp For sending messages to or receiving messages from a Stomp compliant broker, such as Apache ActiveMQ.
Stream stream:[in|out|err|header][?Options] camel-stream Read or write to an input/output/error/file stream rather like Unix pipes.
String Template string-template:TemplateURI[?Options] camel-stringtemplate Generates a response using a String Template.
Stub stub:SomeOtherCamelUri camel-core Allows you to stub out some physical middleware endpoint for easier testing or debugging.
Test test:RouterEndpointUri camel-spring Creates a Mock endpoint which expects to receive all the message bodies that could be polled from the given underlying endpoint.
Timer timer:EndpointID[?Options] camel-core A timer endpoint.
Twitter twitter://[Endpoint][?Options] camel-twitter A Twitter endpoint.
UrlRewrite N/A camel-urlrewrite Enables you to plug URL rewrite functionality into the HTTP, HTTP4, Jetty, or AHC components.
Validation validator:LocalOrRemoteResource camel-spring Validates the payload of a message using XML Schema and JAXP Validation.
Velocity velocity:TemplateURI[?Options] camel-velocity Generates a response using an Apache Velocity template.
Vertx vertx:ChannelName[?Options] camel-vertx For working with the Vertx Event Bus.
VM vm:EndpointID camel-core Used to deliver messages to a java.util.concurrent.BlockingQueue, useful when creating SEDA style processing pipelines within the same JVM.
Weather weather://DummyName[?Options] camel-weather Polls weather information from Open Weather Map: a site that provides free global weather and forecast information.
Websocket websocket://Hostname[:Port]/Path camel-websocket Communicating with Websocket clients.
XML RPC xmlrpc://ServerURI[?Options] camel-xmlrpc Provides a data format for XML, which allows serialization and deserialization of request messages and response message using Apache XmlRpc's bindary data format.
XML Security N/A camel-xmlsecurity Generate and validate XML signatures as described in the W3C standard XML Signature Syntax and Processing.
XMPP xmpp:Hostname[:Port][/Room] camel-xmpp Working with XMPP and Jabber.
XQuery xquery:TemplateURI camel-saxon Generates a response using an XQuery template.
XSLT xslt:TemplateURI[?Options] camel-spring Enables you to process a message using an XSLT template.
Yammer yammer:[function][?Options] camel-yammer Enables you to interact with the Yammer enterprise social network.
Zookeeper zookeeper://Hostname[:Port]/Path camel-zookeeper Working with ZooKeeper cluster(s).

Chapter 2. ActiveMQ

ActiveMQ Component

The ActiveMQ component allows messages to be sent to a JMS Queue or Topic; or messages to be consumed from a JMS Queue or Topic using Apache ActiveMQ.
This component is based on the JMS Component and uses Spring's JMS support for declarative transactions, using Spring's JmsTemplate for sending and a MessageListenerContainer for consuming. All the options from the JMS component also apply for this component.
To use this component, make sure you have the activemq.jar or activemq-core.jar on your classpath along with any Apache Camel dependencies such as camel-core.jar, camel-spring.jar and camel-jms.jar.

Transacted and caching

See section Transactions and Cache Levels below on JMS page if you are using transactions with JMS as it can impact performance.

URI format

activemq:[queue:|topic:]destinationName
Where destinationName is an ActiveMQ queue or topic name. By default, the destinationName is interpreted as a queue name. For example, to connect to the queue, FOO.BAR, use:
activemq:FOO.BAR
You can include the optional queue: prefix, if you prefer:
activemq:queue:FOO.BAR
To connect to a topic, you must include the topic: prefix. For example, to connect to the topic, Stocks.Prices, use:
activemq:topic:Stocks.Prices

Options

See Options on the JMS component as all these options also apply for this component.

Configuring the Connection Factory

The following test case shows how to add an ActiveMQComponent to the CamelContext using the activeMQComponent() method while specifying the brokerURL used to connect to ActiveMQ.
camelContext.addComponent("activemq", activeMQComponent("vm://localhost?broker.persistent=false"));

Configuring the Connection Factory using Spring XML

You can configure the ActiveMQ broker URL on the ActiveMQComponent as follows
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="
       http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
       http://camel.apache.org/schema/spring http://camel.apache.org/schema/spring/camel-spring.xsd">

  <camelContext xmlns="http://camel.apache.org/schema/spring">
  </camelContext>


  <bean id="activemq" class="org.apache.activemq.camel.component.ActiveMQComponent">
    <property name="brokerURL" value="tcp://somehost:61616"/>
  </bean>

</beans>

Using connection pooling

When sending to an ActiveMQ broker using Camel it's recommended to use a pooled connection factory to handle efficient pooling of JMS connections, sessions and producers. This is documented in the page ActiveMQ Spring Support.
You can grab Jencks AMQ pool with Maven:
    <dependency>
      <groupId>org.apache.activemq</groupId>
      <artifactId>activemq-pool</artifactId>
      <version>5.3.2</version>
    </dependency>
And then setup the activemq component as follows:
     <bean id="jmsConnectionFactory" class="org.apache.activemq.ActiveMQConnectionFactory">
        <property name="brokerURL" value="tcp://localhost:61616" />
    </bean>

    <bean id="pooledConnectionFactory"    class="org.apache.activemq.pool.PooledConnectionFactory" init-method="start" destroy-method="stop">
        <property name="maxConnections" value="8" />
        <property name="connectionFactory" ref="jmsConnectionFactory" />
    </bean>


    <bean id="jmsConfig" class="org.apache.camel.component.jms.JmsConfiguration">
        <property name="connectionFactory" ref="pooledConnectionFactory"/>
        <property name="concurrentConsumers" value="10"/>
    </bean>

    <bean id="activemq" class="org.apache.activemq.camel.component.ActiveMQComponent">
        <property name="configuration" ref="jmsConfig"/>
    </bean>

Note

Notice the init and destroy methods on the pooled connection factory. This is important to ensure the connection pool is properly started and shutdown.
The PooledConnectionFactory will then create a connection pool with up to 8 connections in use at the same time. Each connection can be shared by many sessions. There is an option named maxActive you can use to configure the maximum number of sessions per connection; the default value is 500. From ActiveMQ 5.7 onwards the option has been renamed to better reflect its purpose, being named as maxActiveSessionPerConnection. Notice the concurrentConsumers is set to a higher value than maxConnections is. This is okay, as each consumer is using a session, and as a session can share the same connection, we are in the safe. In this example we can have 8 * 500 = 4000 active sessions at the same time.

Invoking MessageListener POJOs in a route

The ActiveMQ component also provides a helper Type Converter from a JMS MessageListener to a Processor. This means that the Bean component is capable of invoking any JMS MessageListener bean directly inside any route.
So for example you can create a MessageListener in JMS as follows:
public class MyListener implements MessageListener {
   public void onMessage(Message jmsMessage) {
       // ...
   }
}
Then use it in your route as follows
from("file://foo/bar").
  bean(MyListener.class);
That is, you can reuse any of the Apache Camel Components and easily integrate them into your JMS MessageListener POJO\!

Using ActiveMQ Destination Options

Available as of ActiveMQ 5.6
You can configure the Destination Options in the endpoint uri, using the "destination." prefix. For example to mark a consumer as exclusive, and set its prefetch size to 50, you can do as follows:
<camelContext xmlns="http://camel.apache.org/schema/spring">
  <route>
    <from uri="file://src/test/data?noop=true"/>
    <to uri="activemq:queue:foo"/>
  </route>
  <route>
    <!-- use consumer.exclusive ActiveMQ destination option, notice we have to prefix with destination. -->
    <from uri="activemq:foo?destination.consumer.exclusive=true&estination.consumer.prefetchSize=50"/>
    <to uri="mock:results"/>
  </route>
</camelContext>

Consuming Advisory Messages

ActiveMQ can generate Advisory messages which are put in topics that you can consume. Such messages can help you send alerts in case you detect slow consumers or to build statistics (number of messages/produced per day, etc.) The following Spring DSL example shows you how to read messages from a topic.
<route>
	<from uri="activemq:topic:ActiveMQ.Advisory.Connection?mapJmsMessage=false" />
	<convertBodyTo type="java.lang.String"/>
	<transform>
	     <simple>${in.body}&#13;</simple>
	</transform>
	<to uri="file://data/activemq/?fileExist=Append&ileName=advisoryConnection-${date:now:yyyyMMdd}.txt" />
</route>

If you consume a message on a queue, you should see the following files under data/activemq folder :
advisoryConnection-20100312.txt advisoryProducer-20100312.txt
and containing string:
      ActiveMQMessage {commandId = 0, responseRequired = false, messageId = ID:dell-charles-3258-1268399815140
      -1:0:0:0:221, originalDestination = null, originalTransactionId = null, producerId = ID:dell-charles-
      3258-1268399815140-1:0:0:0, destination = topic://ActiveMQ.Advisory.Connection, transactionId = null, 
      expiration = 0, timestamp = 0, arrival = 0, brokerInTime = 1268403383468, brokerOutTime = 1268403383468, 
      correlationId = null, replyTo = null, persistent = false, type = Advisory, priority = 0, groupID = null, 
      groupSequence = 0, targetConsumerId = null, compressed = false, userID = null, content = null, 
      marshalledProperties = org.apache.activemq.util.ByteSequence@17e2705, dataStructure = ConnectionInfo 
      {commandId = 1, responseRequired = true, connectionId = ID:dell-charles-3258-1268399815140-2:50, 
      clientId = ID:dell-charles-3258-1268399815140-14:0, userName = , password = *****, 
      brokerPath = null, brokerMasterConnector = false, manageable = true, clientMaster = true}, 
      redeliveryCounter = 0, size = 0, properties = {originBrokerName=master, originBrokerId=ID:dell-charles-
      3258-1268399815140-0:0, originBrokerURL=vm://master}, readOnlyProperties = true, readOnlyBody = true, 
      droppable = false}

Getting Component JAR

You need this dependency:
  • activemq-camel
ActiveMQ is an extension of the JMS component released with the ActiveMQ project.
<dependency>
  <groupId>org.apache.activemq</groupId>
  <artifactId>activemq-camel</artifactId>
  <version>5.6.0</version>
</dependency>

Chapter 3. AHC

Async Http Client (AHC) Component

Available as of Camel 2.8
The ahc: component provides HTTP based endpoints for consuming external HTTP resources (as a client to call external servers using HTTP). The component uses the Async Http Client library.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-ahc</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

ahc:http://hostname[:port][/resourceUri][?options]
ahc:https://hostname[:port][/resourceUri][?options]
Will by default use port 80 for HTTP and 443 for HTTPS.
You can append query options to the URI in the following format, ?option=value&option=value&...

AhcEndpoint Options

Name Default Value Description
throwExceptionOnFailure true Option to disable throwing the AhcOperationFailedException in case of failed responses from the remote server. This allows you to get all responses regardless of the HTTP status code.
bridgeEndpoint false If the option is true, then the Exchange.HTTP_URI header is ignored, and use the endpoint's URI for request. You may also set the throwExcpetionOnFailure to be false to let the AhcProducer send all the fault response back.
transferException false If enabled and an Exchange failed processing on the consumer side, and if the caused Exception was send back serialized in the response as a application/x-java-serialized-object content type (for example using Jetty or Servlet Camel components). On the producer side the exception will be deserialized and thrown as is, instead of the AhcOperationFailedException. The caused exception is required to be serialized.
client null To use a custom com.ning.http.client.AsyncHttpClient.
clientConfig null To configure the AsyncHttpClient to use a custom com.ning.http.client.AsyncHttpClientConfig.
clientConfig.x null To configure additional properties of the com.ning.http.client.AsyncHttpClientConfig instance used by the endpoint. Note that configuration options set using this parameter will be merged with those set using the clientConfig parameter or the instance set at the component level with properties set using this parameter taking priority.
clientConfig.realm.x null Camel 2.11: To configure realm properties of the com.ning.http.client.AsyncHttpClientConfig The options which can be used are the options from com.ning.http.client.Realm.RealmBuilder. eg to set scheme, you can configure "clientConfig.realm.scheme=DIGEST"
binding null To use a custom org.apache.camel.component.ahc.AhcBinding.
sslContextParameters null Camel 2.9: Reference to a org.apache.camel.util.jsse.SSLContextParameters in the CAMEL:Registry. This reference overrides any configured SSLContextParameters at the component level. See Using the JSSE Configuration Utility. Note that configuring this option will override any SSL/TLS configuration options provided through the clientConfig option at the endpoint or component level.
bufferSize 4096 Camel 2.10.3: The initial in-memory buffer size used when transferring data between Camel and AHC Client.

AhcComponent Options

Name Default Value Description
client null To use a custom com.ning.http.client.AsyncHttpClient.
clientConfig null To configure the AsyncHttpClients use a custom com.ning.http.client.AsyncHttpClientConfig.
binding null To use a custom org.apache.camel.component.ahc.AhcBinding.
sslContextParameters null Camel 2.9: To configure custom SSL/TLS configuration options at the component level. See Using the JSSE Configuration Utility for more details. Note that configuring this option will override any SSL/TLS configuration options provided through the clientConfig option at the endpoint or component level.
Notice that setting any of the options on the AhcComponent will propagate those options to AhcEndpoints being created. However the AhcEndpoint can also configure/override a custom option. Options set on endpoints will always take precedence over options from the AhcComponent.

Message Headers

Name Type Description
Exchange.HTTP_URI String URI to call. Will override existing URI set directly on the endpoint.
Exchange.HTTP_PATH String Request URI's path, the header will be used to build the request URI with the HTTP_URI. If the path is start with "/", http producer will try to find the relative path based on the Exchange.HTTP_BASE_URI header or the exchange.getFromEndpoint().getEndpointUri();
Exchange.HTTP_QUERY String URI parameters. Will override existing URI parameters set directly on the endpoint.
Exchange.HTTP_RESPONSE_CODE int The HTTP response code from the external server. Is 200 for OK.
Exchange.HTTP_CHARACTER_ENCODING String Character encoding.
Exchange.CONTENT_TYPE String The HTTP content type. Is set on both the IN and OUT message to provide a content type, such as text/html.
Exchange.CONTENT_ENCODING String The HTTP content encoding. Is set on both the IN and OUT message to provide a content encoding, such as gzip.

Message Body

Camel will store the HTTP response from the external server on the OUT body. All headers from the IN message will be copied to the OUT message, so headers are preserved during routing. Additionally Camel will add the HTTP response headers as well to the OUT message headers.

Response code

Camel will handle according to the HTTP response code:
  • Response code is in the range 100..299, Camel regards it as a success response.
  • Response code is in the range 300..399, Camel regards it as a redirection response and will throw a AhcOperationFailedException with the information.
  • Response code is 400+, Camel regards it as an external server failure and will throw a AhcOperationFailedException with the information. The option, throwExceptionOnFailure, can be set to false to prevent the AhcOperationFailedException from being thrown for failed response codes. This allows you to get any response from the remote server.

AhcOperationFailedException

This exception contains the following information:
  • The HTTP status code
  • The HTTP status line (text of the status code)
  • Redirect location, if server returned a redirect
  • Response body as a java.lang.String, if server provided a body as response

Calling using GET or POST

The following algorithm is used to determine if either GET or POST HTTP method should be used: 1. Use method provided in header. 2. GET if query string is provided in header. 3. GET if endpoint is configured with a query string. 4. POST if there is data to send (body is not null). 5. GET otherwise.

Configuring URI to call

You can set the HTTP producer's URI directly form the endpoint URI. In the route below, Camel will call out to the external server, oldhost, using HTTP.
from("direct:start")
	    .to("ahc:http://oldhost");
And the equivalent Spring sample:
<camelContext xmlns="http://activemq.apache.org/camel/schema/spring">
  <route>
    <from uri="direct:start"/>
    <to uri="ahc:http://oldhost"/>
  </route>
</camelContext>
You can override the HTTP endpoint URI by adding a header with the key, Exchange.HTTP_URI, on the message.
from("direct:start")
    .setHeader(Exchange.HTTP_URI, constant("http://newhost"))
    .to("ahc:http://oldhost");

Configuring URI Parameters

The ahc producer supports URI parameters to be sent to the HTTP server. The URI parameters can either be set directly on the endpoint URI or as a header with the key Exchange.HTTP_QUERY on the message.
from("direct:start")
	    .to("ahc:http://oldhost?order=123&detail=short");
Or options provided in a header:
from("direct:start")
            .setHeader(Exchange.HTTP_QUERY, constant("order=123&detail=short"))
	    .to("ahc:http://oldhost");

How to set the http method (GET/POST/PUT/DELETE/HEAD/OPTIONS/TRACE) to the HTTP producer

The HTTP component provides a way to set the HTTP request method by setting the message header. Here is an example;
from("direct:start")
            .setHeader(Exchange.HTTP_METHOD, constant("POST"))
	    .to("ahc:http://www.google.com")
            .to("mock:results");
And the equivalent Spring sample:
<camelContext xmlns="http://activemq.apache.org/camel/schema/spring">
  <route>
    <from uri="direct:start"/>
    <setHeader headerName="CamelHttpMethod">
        <constant>POST</constant>
    </setHeader>
    <to uri="ahc:http://www.google.com"/>
    <to uri="mock:results"/>
  </route>
</camelContext>

Configuring charset

If you are using POST to send data you can configure the charset using the Exchange property:
exchange.setProperty(Exchange.CHARSET_NAME, "iso-8859-1");

URI Parameters from the endpoint URI

In this sample we have the complete URI endpoint that is just what you would have typed in a web browser. Multiple URI parameters can of course be set using the & character as separator, just as you would in the web browser. Camel does no tricks here.
// we query for Camel at the Google page
template.sendBody("ahc:http://www.google.com/search?q=Camel", null);

URI Parameters from the Message

Map headers = new HashMap();
headers.put(Exchange.HTTP_QUERY, "q=Camel&lr=lang_en");
// we query for Camel and English language at Google
template.sendBody("ahc:http://www.google.com/search", null, headers);
In the header value above notice that it should not be prefixed with ? and you can separate parameters as usual with the & char.

Getting the Response Code

You can get the HTTP response code from the AHC component by getting the value from the Out message header with Exchange.HTTP_RESPONSE_CODE.
Exchange exchange = template.send("ahc:http://www.google.com/search", new Processor() {
            public void process(Exchange exchange) throws Exception {
                exchange.getIn().setHeader(Exchange.HTTP_QUERY, constant("hl=en&q=activemq"));
            }
   });
   Message out = exchange.getOut();
   int responseCode = out.getHeader(Exchange.HTTP_RESPONSE_CODE, Integer.class);

Configuring AsyncHttpClient

The AsyncHttpClient client uses a AsyncHttpClientConfig to configure the client. See the documentation at Async Http Client for more details.
The example below shows how to use a builder to create the AsyncHttpClientConfig which we configure on the AhcComponent.
// create a client config builder
AsyncHttpClientConfig.Builder builder = new AsyncHttpClientConfig.Builder();
// use the builder to set the options we want, in this case we want to follow redirects and try
// at most 3 retries to send a request to the host
AsyncHttpClientConfig config = builder.setFollowRedirects(true).setMaxRequestRetry(3).build();

// lookup AhcComponent
AhcComponent component = context.getComponent("ahc", AhcComponent.class);
// and set our custom client config to be used
component.setClientConfig(config);
In Camel 2.9, the AHC component uses Async HTTP library 1.6.4. This newer version provides added support for plain bean style configuration. The AsyncHttpClientConfigBean class provides getters and setters for the configuration options available in AsyncHttpClientConfig. An instance of AsyncHttpClientConfigBean may be passed directly to the AHC component or referenced in an endpoint URI using the clientConfig URI parameter.
Also available in Camel 2.9 is the ability to set configuration options directly in the URI. URI parameters starting with "clientConfig." can be used to set the various configurable properties of AsyncHttpClientConfig. The properties specified in the endpoint URI are merged with those specified in the configuration referenced by the "clientConfig" URI parameter with those being set using the "clientConfig." parameter taking priority. The AsyncHttpClientConfig instance referenced is always copied for each endpoint such that settings on one endpoint will remain independent of settings on any previously created endpoints. The example below shows how to configure the AHC component using the "clientConfig." type URI parameters.
from("direct:start")
    .to("ahc:http://localhost:8080/foo?clientConfig.maxRequestRetry=3&clientConfig.followRedirects=true")

SSL Support (HTTPS)

Using the JSSE Configuration Utility

As of Camel 2.9, the AHC component supports SSL/TLS configuration through the Camel JSSE Configuration Utility.  This utility greatly decreases the amount of component specific code you need to write and is configurable at the endpoint and component levels. The following examples demonstrate how to use the utility with the AHC component.

Programmatic configuration of the component

KeyStoreParameters ksp = new KeyStoreParameters();
ksp.setResource("/users/home/server/keystore.jks");
ksp.setPassword("keystorePassword");

KeyManagersParameters kmp = new KeyManagersParameters();
kmp.setKeyStore(ksp);
kmp.setKeyPassword("keyPassword");

SSLContextParameters scp = new SSLContextParameters();
scp.setKeyManagers(kmp);

AhcComponent component = context.getComponent("ahc", AhcComponent.class);
component.setSslContextParameters(scp));

Spring DSL based configuration of endpoint

...
  <camel:sslContextParameters
      id="sslContextParameters">
    <camel:keyManagers
        keyPassword="keyPassword">
      <camel:keyStore
          resource="/users/home/server/keystore.jks"
          password="keystorePassword"/>
    </camel:keyManagers>
  </camel:sslContextParameters>...
...
  <to uri="ahc:https://localhost/foo?sslContextParameters=#sslContextParameters"/>
...

Chapter 4. AMQP

AMQP

The AMQP component supports the AMQP protocol via the Qpid project.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-ampq</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

amqp:[queue:|topic:]destinationName[?options]
You can specify all of the various configuration options of the JMS component after the destination name.

Chapter 5. APNS

Apns Component

Available as of Camel 2.8
The apns component is used for sending notifications to iOS devices. The apns components use javapns library. The component supports sending notifications to Apple Push Notification Servers (APNS) and consuming feedback from the servers.
The consumer is configured with 3600 seconds for polling by default because it is a best practice to consume feedback stream from Apple Push Notification Servers only from time to time. For example: every 1 hour to avoid flooding the servers.
The feedback stream gives informations about inactive devices. You only need to get this informations every some hours if your mobile application is not a heavily used one.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-apns</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

To send notifications:
apns:notify[?options]

To consume feedback:
apns:consumer[?options]

Options

Producer

Property Default Description
tokens Empty by default. Configure this property in case you want to statically declare tokens related to devices you want to notify. Tokens are separated by comma.

Consumer

Property Default Description
delay 3600 Delay in seconds between each poll.
initialDelay 10 Seconds before polling starts.
timeUnit SECONDS Time Unit for polling.
userFixedDelay true If true, use fixed delay between pools, otherwise fixed rate is used. See ScheduledExecutorService in JDK for details.
You can append query options to the URI in the following format, ?option=value&option=value&...

Component

The ApnsComponent must be configured with a com.notnoop.apns.ApnsService. The service can be created and configured using the org.apache.camel.component.apns.factory.ApnsServiceFactory. See further below for an example. And as well in the test source code.

Exchange data format

When Camel will fetch feedback data corresponding to inactive devices, it will retrieve a List of InactiveDevice objects. Each InactiveDevice object of the retrieved list will be setted as the In body, and then processed by the consumer endpoint.

Message Headers

Camel Apns uses these headers.
Property Default Description
CamelApnsTokens Empty by default.
CamelApnsMessageType STRING, PAYLOAD In case you choose PAYLOAD for the message type, then the message will be considered as a APNS payload and sent as is. In case you choose STRING, message will be converted as a APNS payload

Samples

Camel Xml route

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:camel="http://camel.apache.org/schema/spring"
       xsi:schemaLocation="
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
        http://camel.apache.org/schema/spring http://camel.apache.org/schema/spring/camel-spring.xsd">

	<!-- Replace by desired values -->
	<bean id="apnsServiceFactory" class="org.apache.camel.component.apns.factory.ApnsServiceFactory">

		<!-- Optional configuration of feedback host and port -->
		<!-- <property name="feedbackHost" value="localhost" /> -->
		<!-- <property name="feedbackPort" value="7843" /> -->

		<!-- Optional configuration of gateway host and port -->
		<!-- <property name="gatewayHost" value="localhost" /> -->
		<!-- <property name="gatewayPort" value="7654" /> -->

		<!-- Declaration of certificate used -->
                <!-- from Camel 2.11 onwards you can use prefix: classpath:, file: to refer to load the certificate from classpath or file. Default it classpath -->
		<property name="certificatePath" value="certificate.p12" />
		<property name="certificatePassword" value="MyCertPassword" />

		<!-- Optional connection strategy - By Default: No need to configure -->
		<!-- Possible options: NON_BLOCKING, QUEUE, POOL or Nothing -->
		<!-- <property name="connectionStrategy" value="POOL" /> -->
		<!-- Optional pool size -->
		<!-- <property name="poolSize" value="15" /> -->

		<!-- Optional connection strategy - By Default: No need to configure -->
		<!-- Possible options: EVERY_HALF_HOUR, EVERY_NOTIFICATION or Nothing (Corresponds to NEVER javapns option) -->
		<!-- <property name="reconnectionPolicy" value="EVERY_HALF_HOUR" /> -->
	</bean>

	<bean id="apnsService" factory-bean="apnsServiceFactory" factory-method="getApnsService" />

	<!-- Replace this declaration by wanted configuration -->
	<bean id="apns" class="org.apache.camel.component.apns.ApnsComponent">
		<property name="apnsService" ref="apnsService" />
	</bean>

	<camelContext id="camel-apns-test" xmlns="http://camel.apache.org/schema/spring">
        	<route id="apns-test">
                	<from uri="apns:consumer?initialDelay=10&elay=3600&imeUnit=SECONDS" />
        	        <to uri="log:org.apache.camel.component.apns?showAll=true&ultiline=true" />
                	<to uri="mock:result" />
        	</route>
	</camelContext>

</beans>

Camel Java route

Create camel context and declare apns component programmatically

    protected CamelContext createCamelContext() throws Exception {
        CamelContext camelContext = super.createCamelContext();

        ApnsServiceFactory apnsServiceFactory = new ApnsServiceFactory();
        apnsServiceFactory.setCertificatePath("classpath:/certificate.p12");
        apnsServiceFactory.setCertificatePassword("MyCertPassword");

        ApnsService apnsService = apnsServiceFactory.getApnsService(camelContext);

        ApnsComponent apnsComponent = new ApnsComponent(apnsService);
        camelContext.addComponent("apns", apnsComponent);

        return camelContext;
    }

ApnsProducer - iOS target device dynamically configured via header: "CamelApnsTokens"

    protected RouteBuilder createRouteBuilder() throws Exception {
        return new RouteBuilder() {
            public void configure() throws Exception {
                from("direct:test")
                    .setHeader(ApnsConstants.HEADER_TOKENS, constant(IOS_DEVICE_TOKEN))
                    .to("apns:notify");
                }
        }
    }

ApnsProducer - iOS target device statically configured via uri

    protected RouteBuilder createRouteBuilder() throws Exception {
        return new RouteBuilder() {
            public void configure() throws Exception {
                from("direct:test").
                to("apns:notify?tokens=" + IOS_DEVICE_TOKEN);
            }
        };
    }

ApnsConsumer

from("apns:consumer?initialDelay=10&delay=3600&timeUnit=SECONDS")
    .to("log:com.apache.camel.component.apns?showAll=true&multiline=true")
    .to("mock:result");

Chapter 6. Atom

Atom Component

The atom: component is used for polling atom feeds.
Apache Camel will poll the feed every 60 seconds by default. Note: The component currently only supports polling (consuming) feeds.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-atom</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

atom://atomUri[?options]
Where atomUri is the URI to the Atom feed to poll.

Options

Property Default Description
splitEntries true If true Apache Camel will poll the feed and for the subsequent polls return each entry poll by poll. If the feed contains 7 entries then Apache Camel will return the first entry on the first poll, the 2nd entry on the next poll, until no more entries where as Apache Camel will do a new update on the feed. If false then Apache Camel will poll a fresh feed on every invocation.
filter true Is only used by the split entries to filter the entries to return. Apache Camel will default use the UpdateDateFilter that only return new entries from the feed. So the client consuming from the feed never receives the same entry more than once. The filter will return the entries ordered by the newest last.
lastUpdate null Is only used by the filter, as the starting timestamp for selection never entries (uses the entry.updated timestamp). Syntax format is: yyyy-MM-ddTHH:MM:ss. Example: 2007-12-24T17:45:59.
throttleEntries true Camel 2.5: Sets whether all entries identified in a single feed poll should be delivered immediately. If true, only one entry is processed per consumer.delay. Only applicable when splitEntries is set to true.
feedHeader true Sets whether to add the Abdera Feed object as a header.
sortEntries false If splitEntries is true, this sets whether to sort those entries by updated date.
consumer.delay 60000 Delay in millis between each poll.
consumer.initialDelay 1000 Millis before polling starts.
consumer.userFixedDelay false If true, use fixed delay between pools, otherwise fixed rate is used. See ScheduledExecutorService in JDK for details.
You can append query options to the URI in the following format, ?option=value&option=value&...

Exchange data format

Apache Camel will set the In body on the returned Exchange with the entries. Depending on the splitEntries flag Apache Camel will either return one Entry or a List<Entry>.
Option Value Behavior
splitEntries true Only a single entry from the currently being processed feed is set: exchange.in.body(Entry)
splitEntries false The entire list of entries from the feed is set: exchange.in.body(List<Entry>)
Apache Camel can set the Feed object on the in header (see feedHeader option to disable this):

Message Headers

Apache Camel atom uses these headers.
Header Description
CamelAtomFeed Apache Camel 2.0: When consuming the org.apache.abdera.model.Feed object is set to this header.

Samples

In the following sample we poll James Strachan's blog:
from("atom://http://macstrac.blogspot.com/feeds/posts/default").to("seda:feeds");
In this sample we want to filter only good blogs we like to a SEDA queue. The sample also shows how to set up Apache Camel standalone, not running in any container or using Spring.
@Override
protected CamelContext createCamelContext() throws Exception {
    // First we register a blog service in our bean registry
    SimpleRegistry registry = new SimpleRegistry();
    registry.put("blogService", new BlogService());

    // Then we create the camel context with our bean registry
    context = new DefaultCamelContext(registry);

    // Then we add all the routes we need using the route builder DSL syntax
    context.addRoutes(createMyRoutes());

    // And finally we must start Camel to let the magic routing begins
    context.start();

    return context;
}

/**
 * This is the route builder where we create our routes using the Camel DSL syntax
 */
protected RouteBuilder createMyRoutes() throws Exception {
    return new RouteBuilder() {
        public void configure() throws Exception {
            // We pool the atom feeds from the source for further processing in the seda queue
            // we set the delay to 1 second for each pool as this is a unit test also and we can
            // not wait the default poll interval of 60 seconds.
            // Using splitEntries=true will during polling only fetch one Atom Entry at any given time.
            // As the feed.atom file contains 7 entries, using this will require 7 polls to fetch the entire
            // content. When Camel have reach the end of entries it will refresh the atom feed from URI source
            // and restart - but as Camel by default uses the UpdatedDateFilter it will only deliver new
            // blog entries to "seda:feeds". So only when James Straham updates his blog with a new entry
            // Camel will create an exchange for the seda:feeds.
            from("atom:file:src/test/data/feed.atom?splitEntries=true&consumer.delay=1000").to("seda:feeds");

            // From the feeds we filter each blot entry by using our blog service class
            from("seda:feeds").filter().method("blogService", "isGoodBlog").to("seda:goodBlogs");

            // And the good blogs is moved to a mock queue as this sample is also used for unit testing
            // this is one of the strengths in Camel that you can also use the mock endpoint for your
            // unit tests
            from("seda:goodBlogs").to("mock:result");
        }
    };
}

/**
 * This is the actual junit test method that does the assertion that our routes is working
 * as expected
 */
@Test
public void testFiltering() throws Exception {
    // create and start Camel
    context = createCamelContext();
    context.start();

    // Get the mock endpoint
    MockEndpoint mock = context.getEndpoint("mock:result", MockEndpoint.class);

    // There should be at least two good blog entries from the feed
    mock.expectedMinimumMessageCount(2);

    // Asserts that the above expectations is true, will throw assertions exception if it failed
    // Camel will default wait max 20 seconds for the assertions to be true, if the conditions
    // is true sooner Camel will continue
    mock.assertIsSatisfied();

    // stop Camel after use
    context.stop();
}

/**
 * Services for blogs
 */
public class BlogService {

    /**
     * Tests the blogs if its a good blog entry or not
     */
    public boolean isGoodBlog(Exchange exchange) {
        Entry entry = exchange.getIn().getBody(Entry.class);
        String title = entry.getTitle();            

        // We like blogs about Camel
        boolean good = title.toLowerCase().contains("camel");
        return good;
    }

}

Chapter 7. avro

Avro Component

Available as of Camel 2.10
This component provides a dataformat for avro, which allows serialization and deserialization of messages using Apache Avro's binary dataformat. Moreover, it provides support for Apache Avro's rpc, by providing producers and consumers endpoint for using avro over netty or http.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-avro</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

Apache Avro Overview

Avro allows you to define message types and a protocol using a json like format and then generate java code for the specified types and messages. An example of how a schema looks like is below.
{"namespace": "org.apache.camel.avro.generated",
 "protocol": "KeyValueProtocol",

 "types": [
     {"name": "Key", "type": "record",
      "fields": [
          {"name": "key",   "type": "string"}
      ]
     },
     {"name": "Value", "type": "record",
      "fields": [
          {"name": "value",   "type": "string"}
      ]
     }
 ],

 "messages": {
     "put": {
         "request": [{"name": "key", "type": "Key"}, {"name": "value", "type": "Value"} ],
         "response": "null"
     },
     "get": {
         "request": [{"name": "key", "type": "Key"}],
         "response": "Value"
     }
 }
}
You can easily generate classes from a schema, using maven, ant etc. More details can be found at the Apache Avro documentation.
However, it doesn't enforce a schema first approach and you can create schema for your existing classes. Since 2.12 you can use existing protocol interfaces to make RCP calls. You should use interface for the protocol itself and POJO beans or primitive/String classes for parameter and result types. Here is an example of the class that corresponds to schema above:
package org.apache.camel.avro.reflection;

public interface KeyValueProtocol {
    void put(String key, Value value);
    Value get(String key);
}

class Value {
    private String value;
    public String getValue() { return value; }
    public void setValue(String value) { this.value = value; }
}
Note: Existing classes can be used only for RPC (see below), not in data format.

Using the Avro data format

Using the avro data format is as easy as specifying that the class that you want to marshal or unmarshal in your route.
    <camelContext id="camel" xmlns="http://camel.apache.org/schema/spring">
        <route>
            <from uri="direct:in"/>
            <marshal>
                <avro instanceClass="org.apache.camel.dataformat.avro.Message"/>
            </marshal>
            <to uri="log:out"/>
        </route>
    </camelContext>
An alternative can be to specify the dataformat inside the context and reference it from your route.
    <camelContext id="camel" xmlns="http://camel.apache.org/schema/spring">
         <dataFormats>
            <avro id="avro" instanceClass="org.apache.camel.dataformat.avro.Message"/>
        </dataFormats>
        <route>
            <from uri="direct:in"/>
            <marshal ref="avro"/>
            <to uri="log:out"/>
        </route>
    </camelContext>
In the same manner you can umarshal using the avro data format.

Using Avro RPC in Camel

As mentioned above Avro also provides RPC support over multiple transports such as http and netty. Camel provides consumers and producers for these two transports.
avro:[transport]:[host]:[port][?options]
The supported transport values are currently http or netty.
Since 2.12 you can specify message name right in the URI:
avro:[transport]:[host]:[port][/messageName][?options]
For consumers this allows you to have multiple routes attached to the same socket. Dispatching to correct route will be done by the avro component automatically. Route with no messageName specified (if any) will be used as default.
When using camel producers for avro ipc, the "in" message body needs to contain the parameters of the operation specified in the avro protocol. The response will be added in the body of the "out" message.
In a similar manner when using camel avro consumers for avro ipc, the requests parameters will be placed inside the "in" message body of the created exchange and once the exchange is processed the body of the "out" message will be send as a response.
Note: By default consumer parameters are wrapped into array. If you've got only one parameter, since 2.12 you can use singleParameter URI option to receive it direcly in the "in" message body without array wrapping.

Avro RPC URI Options

Name Version Description
protocolClassName The class name of the avro protocol.
singleParameter 2.12 If true, consumer parameter won't be wrapped into array. Will fail if protocol specifies more then 1 parameter for the message
protocol Avro procol object. Can be used instead of protocolClassName when complex protocol needs to be created. One cane used #name notation to refer beans from the Registry
reflectionProtocol 2.12 If protocol object provided is reflection protocol. Should be used only with protocol parameter because for protocolClassName protocol type will be autodetected

Avro RPC Headers

Name Description
CamelAvroMessageName The name of the message to send. In consumer overrides message name from URI (if any)

Examples

An example of using camel avro producers via http:
        <route>
            <from uri="direct:start"/>
            <to uri="avro:http:localhost:{{avroport}}?protocolClassName=org.apache.camel.avro.generated.KeyValueProtocol"/>
            <to uri="log:avro"/>
        </route>
In the example above you need to fill CamelAvroMessageName header. Since 2.12 you can use following syntax to call constant messages:
        <route>
            <from uri="direct:start"/>
            <to uri="avro:http:localhost:{{avroport}}/put?protocolClassName=org.apache.camel.avro.generated.KeyValueProtocol"/>
            <to uri="log:avro"/>
        </route>
An example of consuming messages using camel avro consumers via Netty:
        <route>
            <from uri="avro:netty:localhost:{{avroport}}?protocolClassName=org.apache.camel.avro.generated.KeyValueProtocol"/>
            <choice>
                <when>
                    <el>${in.headers.CamelAvroMessageName == 'put'}</el>
                    <process ref="putProcessor"/>
                </when>
                <when>
                    <el>${in.headers.CamelAvroMessageName == 'get'}</el>
                    <process ref="getProcessor"/>
                </when>
            </choice>
        </route>
Since 2.12 you can set up two distinct routes to perform the same task:
        <route>
            <from uri="avro:netty:localhost:{{avroport}}/put?protocolClassName=org.apache.camel.avro.generated.KeyValueProtocol">
            <process ref="putProcessor"/>
        </route>
        <route>
            <from uri="avro:netty:localhost:{{avroport}}/get?protocolClassName=org.apache.camel.avro.generated.KeyValueProtocol&singleParameter=true"/>
            <process ref="getProcessor"/>
        </route>
In the example above, get takes only one parameter, so singleParameter is used and getProcessor will receive Value class directly in body, while putProcessor will receive an array of size 2 with String key and Value value filled as array contents.

Chapter 8. AWS

8.1. Introduction to the AWS Components

Camel Components for Amazon Web Services

The Camel Components for Amazon Web Services provide connectivity to AWS services from Camel.
AWS service Camel component Camel Version Component description
Simple Queue Service (SQS) AWS-SQS 2.6 Supports sending and receiving messages using SQS
Simple Notification Service (SNS) AWS-SNS 2.8 Supports sending messages using SNS
Simple Storage Service (S3) AWS-S3 2.8 Supports storing and retrieving of objects using S3
Simple Email Service (SES) AWS-SES 2.8.4 Supports sending emails using SES
SimpleDB AWS-SDB 2.8.4 Supports storing retrieving data to/from SDB
DynamoDB AWS-DDB 2.10.0 Supports storing retrieving data to/from DDB
CloudWatch AWS-CW 2.10.3 Supports sending metrics to CloudWatch

8.2. AWS-CW

CW Component

*Available as of Camel 2.11
The CW component allows messages to be sent to an Amazon CloudWatch metrics. The implementation of the Amazon API is provided by the AWS SDK.

Prerequisites

You must have a valid Amazon Web Services developer account, and be signed up to use Amazon CloudWatch. More information are available at Amazon CloudWatch.

URI Format

aws-cw://namespace[?options]
The metrics will be created if they don't already exists. You can append query options to the URI in the following format, ?options=value&option2=value&...

URI Options

Name Default Value Context Description
amazonCwClient null Producer Reference to a com.amazonaws.services.cloudwatch.AmazonCloudWatch in the Registry.
accessKey null Producer Amazon AWS Access Key
secretKey null Producer Amazon AWS Secret Key
name null Producer The metric name which is used if the message header 'CamelAwsCwMetricName' is not present.
value 1.0 Producer The metric value which is used if the message header 'CamelAwsCwMetricValue' is not present.
unit Count Producer The metric unit which is used if the message header 'CamelAwsCwMetricUnit' is not present.
namespace null Producer The metric namespace which is used if the message header 'CamelAwsCwMetricNamespace' is not present.
timestamp null Producer The metric timestamp which is used if the message header 'CamelAwsCwMetricTimestamp' is not present.
amazonCwEndpoint null Producer The region with which the AWS-CW client wants to work with.

Required CW component options

You have to provide the amazonCwClient in the Registry or your accessKey and secretKey to access the Amazon's CloudWatch.

Usage

Message headers evaluated by the CW producer

Header Type Description
CamelAwsCwMetricName String The Amazon CW metric name.
CamelAwsCwMetricValue Double The Amazon CW metric value.
CamelAwsCwMetricUnit String The Amazon CW metric unit.
CamelAwsCwMetricNamespace String The Amazon CW metric namespace.
CamelAwsCwMetricTimestamp Date The Amazon CW metric timestamp.
CamelAwsCwMetricDimensionName String Camel 2.12: The Amazon CW metric dimension name.
CamelAwsCwMetricDimensionValue String Camel 2.12: The Amazon CW metric dimension value.
CamelAwsCwMetricDimensions Map<String, String> Camel 2.12: A map of dimension names and dimension values.

Advanced AmazonCloudWatch configuration

If you need more control over the AmazonCloudWatch instance configuration you can create your own instance and refer to it from the URI:
from("direct:start")
.to("aws-cw://namepsace?amazonCwClient=#client");
The #client refers to a AmazonCloudWatch in the Registry.
For example if your Camel Application is running behind a firewall:
AWSCredentials awsCredentials = new BasicAWSCredentials("myAccessKey", "mySecretKey");
ClientConfiguration clientConfiguration = new ClientConfiguration();
clientConfiguration.setProxyHost("http://myProxyHost");
clientConfiguration.setProxyPort(8080);

AmazonCloudWatch client = new AmazonCloudWatchClient(awsCredentials, clientConfiguration);

registry.bind("client", client);

Dependencies

Maven users will need to add the following dependency to their pom.xml.

pom.xml

<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-aws</artifactId>
    <version>${camel-version}</version>
</dependency>
where ${camel-version} must be replaced by the actual version of Camel (2.10 or higher).

8.3. AWS-DDB

DDB Component

Available as of Camel 2.10
The DynamoDB component supports storing and retrieving data from/to Amazon's DynamoDB service.

Prerequisites

You must have a valid Amazon Web Services developer account, and be signed up to use Amazon DynamoDB. More information are available at Amazon DynamoDB.

URI Format

aws-ddb://domainName[?options]
You can append query options to the URI in the following format, ?options=value&option2=value&...

URI Options

Name Default Value Context Description
amazonDDBClient null Producer Reference to a com.amazonaws.services.dynamodb.AmazonDynamoDB in the Registry.
accessKey null Producer Amazon AWS Access Key
secretKey null Producer Amazon AWS Secret Key
amazonDdbEndpoint null Producer The region with which the AWS-DDB client wants to work with.
tableName null Producer The name of the table currently worked with.
readCapacity 0 Producer The provisioned throughput to reserve for reading resources from your table
writeCapacity 0 Producer The provisioned throughput to reserved for writing resources to your table
consistentRead false Producer Determines whether or not strong consistency should be enforced when data is read.
operation PutAttributes Producer Valid values are BatchGetItems, DeleteItem, DeleteTable, DescribeTable, GetItem, PutItem, Query, Scan, UpdateItem, UpdateTable.

Required DDB component options

You have to provide the amazonDDBClient in the Registry or your accessKey and secretKey to access the Amazon's DynamoDB.

Usage

Message headers evaluated by the DDB producer

Header Type Description
CamelAwsDdbBatchItems Map<String, KeysAndAttributes> A map of the table name and corresponding items to get by primary key.
CamelAwsDdbTableName String Table Name for this operation.
CamelAwsDdbKey Key The primary key that uniquely identifies each item in a table.
CamelAwsDdbReturnValues String Use this parameter if you want to get the attribute name-value pairs before or after they are modified(NONE, ALL_OLD, UPDATED_OLD, ALL_NEW, UPDATED_NEW).
CamelAwsDdbUpdateCondition Map<String, ExpectedAttributeValue> Designates an attribute for a conditional modification.
CamelAwsDdbAttributeNames Collection<String> If attribute names are not specified then all attributes will be returned.
CamelAwsDdbConsistentRead Boolean If set to true, then a consistent read is issued, otherwise eventually consistent is used.
CamelAwsDdbItem Map<String, AttributeValue> A map of the attributes for the item, and must include the primary key values that define the item.
CamelAwsDdbExactCount Boolean If set to true, Amazon DynamoDB returns a total number of items that match the query parameters, instead of a list of the matching items and their attributes.
CamelAwsDdbStartKey Key Primary key of the item from which to continue an earlier query.
CamelAwsDdbHashKeyValue AttributeValue Value of the hash component of the composite primary key.
CamelAwsDdbLimit Integer The maximum number of items to return.
CamelAwsDdbScanRangeKeyCondition Condition A container for the attribute values and comparison operators to use for the query.
CamelAwsDdbScanIndexForward Boolean Specifies forward or backward traversal of the index.
CamelAwsDdbScanFilter Map<String, Condition> Evaluates the scan results and returns only the desired values.
CamelAwsDdbUpdateValues Map<String, AttributeValueUpdate> Map of attribute name to the new value and action for the update.

Message headers set during BatchGetItems operation

Header Type Description
CamelAwsDdbBatchResponse Map<String,BatchResponse> Table names and the respective item attributes from the tables.
CamelAwsDdbUnprocessedKeys Map<String,KeysAndAttributes> Contains a map of tables and their respective keys that were not processed with the current response.

Message headers set during DeleteItem operation

Header Type Description
CamelAwsDdbAttributes Map<String, AttributeValue> The list of attributes returned by the operation.

Message headers set during DeleteTable operation

Header Type Description
CamelAwsDdbProvisionedThroughput ProvisionedThroughputDescription The value of the ProvisionedThroughput property for this table
CamelAwsDdbCreationDate Date Creation DateTime of this table.
CamelAwsDdbTableItemCount Long Item count for this table.
CamelAwsDdbKeySchema KeySchema The KeySchema that identifies the primary key for this table.
CamelAwsDdbTableName String The table name.
CamelAwsDdbTableSize Long The table size in bytes.
CamelAwsDdbTableStatus String The status of the table: CREATING, UPDATING, DELETING, ACTIVE

Message headers set during DescribeTable operation

Header Type Description
CamelAwsDdbProvisionedThroughput {{ProvisionedThroughputDescription} The value of the ProvisionedThroughput property for this table
CamelAwsDdbCreationDate Date Creation DateTime of this table.
CamelAwsDdbTableItemCount Long Item count for this table.
CamelAwsDdbKeySchema {{KeySchema The KeySchema that identifies the primary key for this table.
CamelAwsDdbTableName String The table name.
CamelAwsDdbTableSize Long The table size in bytes.
CamelAwsDdbTableStatus String The status of the table: CREATING, UPDATING, DELETING, ACTIVE
CamelAwsDdbReadCapacity Long ReadCapacityUnits property of this table.
CamelAwsDdbWriteCapacity Long WriteCapacityUnits property of this table.

Message headers set during GetItem operation

Header Type Description
CamelAwsDdbAttributes Map<String, AttributeValue> The list of attributes returned by the operation.

Message headers set during PutItem operation

Header Type Description
CamelAwsDdbAttributes Map<String, AttributeValue> The list of attributes returned by the operation.

Message headers set during Query operation

Header Type Description
CamelAwsDdbItems List<java.util.Map<String,AttributeValue>> The list of attributes returned by the operation.
CamelAwsDdbLastEvaluatedKey Key Primary key of the item where the query operation stopped, inclusive of the previous result set.
CamelAwsDdbConsumedCapacity Double The number of Capacity Units of the provisioned throughput of the table consumed during the operation.
CamelAwsDdbCount Integer Number of items in the response.

Message headers set during Scan operation

Header Type Description
CamelAwsDdbItems List<java.util.Map<String,AttributeValue>> The list of attributes returned by the operation.
CamelAwsDdbLastEvaluatedKey Key Primary key of the item where the query operation stopped, inclusive of the previous result set.
CamelAwsDdbConsumedCapacity Double The number of Capacity Units of the provisioned throughput of the table consumed during the operation.
CamelAwsDdbCount Integer Number of items in the response.
CamelAwsDdbScannedCount Integer Number of items in the complete scan before any filters are applied.

Message headers set during UpdateItem operation

Header Type Description
CamelAwsDdbAttributes Map<String, AttributeValue> The list of attributes returned by the operation.

Advanced AmazonDynamoDB configuration

If you need more control over the AmazonDynamoDB instance configuration you can create your own instance and refer to it from the URI:
from("direct:start")
.to("aws-ddb://domainName?amazonDDBClient=#client");
The #client refers to a AmazonDynamoDB in the Registry.
For example if your Camel Application is running behind a firewall:
AWSCredentials awsCredentials = new BasicAWSCredentials("myAccessKey", "mySecretKey");
ClientConfiguration clientConfiguration = new ClientConfiguration();
clientConfiguration.setProxyHost("http://myProxyHost");
clientConfiguration.setProxyPort(8080);

AmazonDynamoDB client = new AmazonDynamoDBClient(awsCredentials, clientConfiguration);

registry.bind("client", client);

Dependencies

Maven users will need to add the following dependency to their pom.xml.

pom.xml

<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-aws</artifactId>
    <version>${camel-version}</version>
</dependency>
where ${camel-version} must be replaced by the actual version of Camel (2.10 or higher).

8.4. AWS-S3

S3 Component

Available as of Camel 2.8
The S3 component supports storing and retrieving objetcs from/to Amazon's S3 service.

Prerequisites

You must have a valid Amazon Web Services developer account, and be signed up to use Amazon S3. More information are available at Amazon S3.

URI Format

aws-s3://bucket-name[?options]
The bucket will be created if it don't already exists. You can append query options to the URI in the following format, ?options=value&option2=value&...

URI Options

Name Default Value Context Description
amazonS3Client null Shared Reference to a com.amazonaws.services.sqs.AmazonS3 in the Registry.
accessKey null Shared Amazon AWS Access Key
secretKey null Shared Amazon AWS Secret Key
amazonS3Endpoint null Shared The region with which the AWS-S3 client wants to work with.
region null Producer The region who the bucket is located. This option is used in the com.amazonaws.services.s3.model.CreateBucketRequest.
deleteAfterRead true Consumer Delete objects from S3 after it has been retrieved.
deleteAfterWrite false Producer Camel 2.11.0 Delete file object after the S3 file has been uploaded
maxMessagesPerPoll 10 Consumer The maximum number of objects which can be retrieved in one poll. Used in in the com.amazonaws.services.s3.model.ListObjectsRequest.
policy null Shared *Camel 2.8.4*: The policy for this queue to set in the com.amazonaws.services.s3.AmazonS3#setBucketPolicy() method.
storageClass null Producer *Camel 2.8.4*: The storage class to set in the com.amazonaws.services.s3.model.PutObjectRequest request.
prefix null Consumer *Camel 2.10.1*: The prefix which is used in the com.amazonaws.services.s3.model.ListObjectsRequest to only consume objects we are interested in.

Required S3 component options

You have to provide the amazonS3Client in the Registry or your accessKey and secretKey to access the Amazon's S3.

Batch Consumer

This component implements the Batch Consumer.
This allows you for instance to know how many messages exists in this batch and for instance let the Aggregator aggregate this number of messages.

Usage

Message headers evaluated by the S3 producer

Header Type Description
CamelAwsS3Key String The key under which this object will be stored.
CamelAwsS3ContentLength Long The content length of this object.
CamelAwsS3ContentType String The content type of this object.
CamelAwsS3ContentControl String The content control of this object.
CamelAwsS3ContentDisposition String The content disposition of this object.
CamelAwsS3ContentEncoding String The content encoding of this object.
CamelAwsS3ContentMD5 String The md5 checksum of this object.
CamelAwsS3LastModified java.util.Date The last modified timestamp of this object.
CamelAwsS3StorageClass String *Camel 2.8.4:* The storage class of this object.
CamelAwsS3CannedAcl String Camel 2.11.0: The canned acl that will be applied to the object. see com.amazonaws.services.s3.model.CannedAccessControlList for allowed values.
CamelAwsS3Acl com.amazonaws.services.s3.model.AccessControlList Camel 2.11.0: a well constructed Amazon S3 Access Control List object. see com.amazonaws.services.s3.model.AccessControlList for more details

Message headers set by the S3 producer

Header Type Description
CamelAwsS3ETag String The ETag value for the newly uploaded object.
CamelAwsS3VersionId String The optional version ID of the newly uploaded object.

Message headers set by the S3 consumer

Header Type Description
CamelAwsS3Key String The key under which this object is stored.
CamelAwsS3BucketName String The name of the bucket in which this object is contained.
CamelAwsS3ETag String The hex encoded 128-bit MD5 digest of the associated object according to RFC 1864. This data is used as an integrity check to verify that the data received by the caller is the same data that was sent by Amazon S3.
CamelAwsS3LastModified Date The value of the Last-Modified header, indicating the date and time at which Amazon S3 last recorded a modification to the associated object.
CamelAwsS3VersionId String The version ID of the associated Amazon S3 object if available. Version IDs are only assigned to objects when an object is uploaded to an Amazon S3 bucket that has object versioning enabled.
CamelAwsS3ContentType String The Content-Type HTTP header, which indicates the type of content stored in the associated object. The value of this header is a standard MIME type.
CamelAwsS3ContentMD5 String The base64 encoded 128-bit MD5 digest of the associated object (content - not including headers) according to RFC 1864. This data is used as a message integrity check to verify that the data received by Amazon S3 is the same data that the caller sent.
CamelAwsS3ContentLength Long The Content-Length HTTP header indicating the size of the associated object in bytes.
CamelAwsS3ContentEncoding String The optional Content-Encoding HTTP header specifying what content encodings have been applied to the object and what decoding mechanisms must be applied in order to obtain the media-type referenced by the Content-Type field.
CamelAwsS3ContentDisposition String The optional Content-Disposition HTTP header, which specifies presentational information such as the recommended filename for the object to be saved as.
CamelAwsS3ContentControl String The optional Cache-Control HTTP header which allows the user to specify caching behavior along the HTTP request/reply chain.

Advanced AmazonS3 configuration

If your Camel Application is running behind a firewall or if you need to have more control over the AmazonS3 instance configuration, you can create your own instance:
AWSCredentials awsCredentials = new BasicAWSCredentials("myAccessKey", "mySecretKey");

ClientConfiguration clientConfiguration = new ClientConfiguration();
clientConfiguration.setProxyHost("http://myProxyHost");
clientConfiguration.setProxyPort(8080);

AmazonS3 client = new AmazonS3Client(awsCredentials, clientConfiguration);

registry.bind("client", client);
and refer to it in your Camel aws-s3 component configuration:
from("aws-s3://MyBucket?amazonS3Client=#client&delay=5000&maxMessagesPerPoll=5")
.to("mock:result");

Dependencies

Maven users will need to add the following dependency to their pom.xml.

pom.xml

<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-aws</artifactId>
    <version>${camel-version}</version>
</dependency>
where $\{camel-version\} must be replaced by the actual version of Camel (2.8 or higher).

8.5. AWS-SDB

SDB Component

Available as of Camel 2.8.4
The sdb component supports storing and retrieving data from/to Amazon's SDB service.

Prerequisites

You must have a valid Amazon Web Services developer account, and be signed up to use Amazon SDB. More information are available at Amazon SDB.

URI Format

aws-sdb://domainName[?options]
You can append query options to the URI in the following format, ?options=value&option2=value&...

URI Options

Name Default Value Context Description
amazonSDBClient null Producer Reference to a com.amazonaws.services.simpledb.AmazonSimpleDB in the Registry.
accessKey null Producer Amazon AWS Access Key
secretKey null Producer Amazon AWS Secret Key
amazonSdbEndpoint null Producer The region with which the AWS-SDB client wants to work with.
domainName null Producer The name of the domain currently worked with.
maxNumberOfDomains 100 Producer The maximum number of domain names you want returned. The range is 1 * to 100.
consistentRead false Producer Determines whether or not strong consistency should be enforced when data is read.
operation PutAttributes Producer Valid values are BatchDeleteAttributes, BatchPutAttributes, DeleteAttributes, DeleteDomain, DomainMetadata, GetAttributes, ListDomains, PutAttributes, Select.

Required SDB component options

You have to provide the amazonSDBClient in the Registry or your accessKey and secretKey to access the Amazon's SDB.

Usage

Message headers evaluated by the SDB producer

Header Type Description
CamelAwsSdbAttributes Collection<Attribute> List of attributes to be acted upon.
CamelAwsSdbAttributeNames Collection<String> The names of the attributes to be retrieved.
CamelAwsSdbConsistentRead Boolean Determines whether or not strong consistency should be enforced when data is read.
CamelAwsSdbDeletableItems Collection<DeletableItem> A list of items on which to perform the delete operation in a batch.
CamelAwsSdbDomainName String The name of the domain currently worked with.
CamelAwsSdbItemName String The unique key for this item
CamelAwsSdbMaxNumberOfDomains Integer The maximum number of domain names you want returned. The range is 1 * to 100.
CamelAwsSdbNextToken String A string specifying where to start the next list of domain/item names.
CamelAwsSdbOperation String To override the operation from the URI options.
CamelAwsSdbReplaceableAttributes Collection<ReplaceableAttribute> List of attributes to put in an Item.
CamelAwsSdbReplaceableItems Collection<ReplaceableItem> A list of items to put in a Domain.
CamelAwsSdbSelectExpression String The expression used to query the domain.
CamelAwsSdbUpdateCondition UpdateCondition The update condition which, if specified, determines whether the specified attributes will be updated/deleted or not.

Message headers set during DomainMetadata operation

Header Type Description
CamelAwsSdbTimestamp Integer The data and time when metadata was calculated, in Epoch (UNIX) seconds.
CamelAwsSdbItemCount Integer The number of all items in the domain.
CamelAwsSdbAttributeNameCount Integer The number of unique attribute names in the domain.
CamelAwsSdbAttributeValueCount Integer The number of all attribute name/value pairs in the domain.
CamelAwsSdbAttributeNameSize Long The total size of all unique attribute names in the domain, in bytes.
CamelAwsSdbAttributeValueSize Long The total size of all attribute values in the domain, in bytes.
CamelAwsSdbItemNameSize Long The total size of all item names in the domain, in bytes.

Message headers set during GetAttributes operation

Header Type Description
CamelAwsSdbAttributes List<Attribute> The list of attributes returned by the operation.

Message headers set during ListDomains operation

Header Type Description
CamelAwsSdbDomainNames List<String> A list of domain names that match the expression.
CamelAwsSdbNextToken String An opaque token indicating that there are more domains than the specified MaxNumberOfDomains still available.

Message headers set during Select operation

Header Type Description
CamelAwsSdbItems List<Item> A list of items that match the select expression.
CamelAwsSdbNextToken String An opaque token indicating that more items than MaxNumberOfItems were matched, the response size exceeded 1 megabyte, or the execution time exceeded 5 seconds.

Advanced AmazonSimpleDB configuration

If you need more control over the AmazonSimpleDB instance configuration you can create your own instance and refer to it from the URI:
from("direct:start")
.to("aws-sdb://domainName?amazonSDBClient=#client");
The #client refers to a AmazonSimpleDB in the Registry.
For example if your Camel Application is running behind a firewall:
AWSCredentials awsCredentials = new BasicAWSCredentials("myAccessKey", "mySecretKey");
ClientConfiguration clientConfiguration = new ClientConfiguration();
clientConfiguration.setProxyHost("http://myProxyHost");
clientConfiguration.setProxyPort(8080);

AmazonSimpleDB client = new AmazonSimpleDBClient(awsCredentials, clientConfiguration);

registry.bind("client", client);

Dependencies

Maven users will need to add the following dependency to their pom.xml.

pom.xml

<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-aws</artifactId>
    <version>${camel-version}</version>
</dependency>
where ${camel-version} must be replaced by the actual version of Camel (2.8.4 or higher).

8.6. AWS-SES

SES Component

Available as of Camel 2.8.4
The ses component supports sending emails with Amazon's SES service.

Prerequisites

You must have a valid Amazon Web Services developer account, and be signed up to use Amazon SES. More information are available at Amazon SES.

URI Format

aws-ses://from[?options]
You can append query options to the URI in the following format, ?options=value&option2=value&...

URI Options

Name Default Value Context Description
amazonSESClient null Producer Reference to a com.amazonaws.services.simpleemail.AmazonSimpleEmailService in the Registry.
accessKey null Producer Amazon AWS Access Key
secretKey null Producer Amazon AWS Secret Key
amazonSESEndpoint null Producer The region with which the AWS-SES client wants to work with.
subject null Producer The subject which is used if the message header 'CamelAwsSesSubject' is not present.
to null Producer List of destination email address. Can be overriden with 'CamelAwsSesTo' header.
returnPath null Producer The email address to which bounce notifications are to be forwarded, override it using 'CamelAwsSesReturnPath' header.
replyToAddresses null Producer List of reply-to email address(es) for the message, override it using 'CamelAwsSesReplyToAddresses' header.

Required SES component options

You have to provide the amazonSESClient in the Registry or your accessKey and secretKey to access the Amazon's SES.

Usage

Message headers evaluated by the SES producer

Header Type Description
CamelAwsSesFrom String The sender's email address.
CamelAwsSesTo List<String> The destination(s) for this email.
CamelAwsSesSubject String The subject of the message.
CamelAwsSesReplyToAddresses List<String> The reply-to email address(es) for the message.
CamelAwsSesReturnPath String The email address to which bounce notifications are to be forwarded.

Message headers set by the SES producer

Header Type Description
CamelAwsSesMessageId String The Amazon SES message ID.

Advanced AmazonSimpleEmailService configuration

If you need more control over the AmazonSimpleEmailService instance configuration you can create your own instance and refer to it from the URI:
from("direct:start")
.to("aws-ses://example@example.com?amazonSESClient=#client");
The #client refers to a AmazonSimpleEmailService in the Registry.
For example if your Camel Application is running behind a firewall:
AWSCredentials awsCredentials = new BasicAWSCredentials("myAccessKey", "mySecretKey");
ClientConfiguration clientConfiguration = new ClientConfiguration();
clientConfiguration.setProxyHost("http://myProxyHost");
clientConfiguration.setProxyPort(8080);
AmazonSimpleEmailService client = new AmazonSimpleEmailServiceClient(awsCredentials, clientConfiguration);

registry.bind("client", client);

Dependencies

Maven users will need to add the following dependency to their pom.xml.

pom.xml

<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-aws</artifactId>
    <version>${camel-version}</version>
</dependency>
where ${camel-version} must be replaced by the actual version of Camel (2.8.4 or higher).

8.7. AWS-SNS

SNS Component

Available as of Camel 2.8
The SNS component allows messages to be sent to an Amazon Simple Notification Topic. The implementation of the Amazon API is provided by the AWS SDK.

Prerequisites

You must have a valid Amazon Web Services developer account, and be signed up to use Amazon SNS. More information are available at Amazon SNS.

URI Format

aws-sns://topicName[?options]
The topic will be created if they don't already exists. You can append query options to the URI in the following format, ?options=value&option2=value&...

URI Options

Name Default Value Context Description
amazonSNSClient null Producer Reference to a com.amazonaws.services.sns.AmazonSNS in the Registry.
accessKey null Producer Amazon AWS Access Key
secretKey null Producer Amazon AWS Secret Key
subject null Producer The subject which is used if the message header 'CamelAwsSnsSubject' is not present.
amazonSNSEndpoint null Producer The region with which the AWS-SNS client wants to work with.
policy null Producer Camel 2.8.4: The policy for this queue to set in the com.amazonaws.services.sns.model.SetTopicAttributesRequest.

Required SNS component options

You have to provide the amazonSNSClient in the Registry or your accessKey and secretKey to access the Amazon's SNS.

Usage

Message headers evaluated by the SNS producer

Header Type Description
CamelAwsSnsSubject String The Amazon SNS message subject. If not set, the subject from the SnsConfiguration is used.

Message headers set by the SNS producer

Header Type Description
CamelAwsSnsMessageId String The Amazon SNS message ID.

Advanced AmazonSNS configuration

If you need more control over the AmazonSNS instance configuration you can create your own instance and refer to it from the URI:
from("direct:start")
.to("aws-sns://MyTopic?amazonSNSClient=#client");
The #client refers to a AmazonSNS in the Registry.
For example if your Camel Application is running behind a firewall:
AWSCredentials awsCredentials = new BasicAWSCredentials("myAccessKey", "mySecretKey");
ClientConfiguration clientConfiguration = new ClientConfiguration();
clientConfiguration.setProxyHost("http://myProxyHost");
clientConfiguration.setProxyPort(8080);
AmazonSNS client = new AmazonSNSClient(awsCredentials, clientConfiguration);

registry.bind("client", client);

Dependencies

Maven users will need to add the following dependency to their pom.xml.

pom.xml

<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-aws</artifactId>
    <version>${camel-version}</version>
</dependency>

where $\{camel-version\} must be replaced by the actual version of Camel (2.8 or higher).

8.8. AWS-SQS

SQS Component

Available as of Camel 2.6
The sqs component supports sending and receiving messages to Amazon's SQS service.

Prerequisites

You must have a valid Amazon Web Services developer account, and be signed up to use Amazon SQS. More information are available at Amazon SQS.

URI Format

aws-sqs://queue-name[?options]
The queue will be created if they don't already exists. You can append query options to the URI in the following format, ?options=value&option2=value&...

URI Options

Name Default Value Context Description
amazonSQSClient null Shared Reference to a com.amazonaws.services.sqs.AmazonSQS in the Registry.
accessKey null Shared Amazon AWS Access Key
secretKey null Shared Amazon AWS Secret Key
amazonSQSEndpoint null Shared The region with which the AWS-SQS client wants to work with.
attributeNames null Consumer A list of attributes to set in the com.amazonaws.services.sqs.model.ReceiveMessageRequest.
defaultVisibilityTimeout null Shared The visibility timeout (in seconds) to set in the com.amazonaws.services.sqs.model.CreateQueueRequest.
deleteAfterRead true Consumer Delete message from SQS after it has been read
maxMessagesPerPoll null Consumer The maximum number of messages which can be received in one poll to set in the com.amazonaws.services.sqs.model.ReceiveMessageRequest.
visibilityTimeout null Shared The duration (in seconds) that the received messages are hidden from subsequent retrieve requests after being retrieved by a ReceiveMessage request to set in the com.amazonaws.services.sqs.model.SetQueueAttributesRequest. This only make sense if its different from defaultVisibilityTimeout. It changes the queue visibility timeout attribute permanently.
messageVisibilityTimeout null Consumer Camel 2.8: The duration (in seconds) that the received messages are hidden from subsequent retrieve requests after being retrieved by a ReceiveMessage request to set in the com.amazonaws.services.sqs.model.ReceiveMessageRequest. It does NOT change the queue visibility timeout attribute permanently.
extendMessageVisibility false Consumer Camel 2.10: If enabled then a scheduled background task will keep extending the message visibility on SQS. This is needed if it taks a long time to process the message. If set to true defaultVisibilityTimeout must be set. See details at Amazon docs.
maximumMessageSize null Shared Camel 2.8: The maximumMessageSize (in bytes) an SQS message can contain for this queue, to set in the com.amazonaws.services.sqs.model.SetQueueAttributesRequest.
messageRetentionPeriod null Shared Camel 2.8: The messageRetentionPeriod (in seconds) a message will be retained by SQS for this queue, to set in the com.amazonaws.services.sqs.model.SetQueueAttributesRequest.
policy null Shared Camel 2.8: The policy for this queue to set in the com.amazonaws.services.sqs.model.SetQueueAttributesRequest.
delaySeconds null Producer Camel 2.9.3: Delay sending messages for a number of seconds.
waitTimeSeconds 0 Producer Camel 2.11: Duration in seconds (0 to 20) that the ReceiveMessage action call will wait until a message is in the queue to include in the response.
receiveMessageWaitTimeSeconds 0 Shared Camel 2.11: If you do not specify WaitTimeSeconds in the request, the queue attribute ReceiveMessageWaitTimeSeconds is used to determine how long to wait.
queueOwnerAWSAccountId null Camel 2.12: Specify the queue owner aws account id when you need to connect the queue with different account owner.

Required SQS component options

You have to provide the amazonSQSClient in the Registry or your accessKey and secretKey to access the Amazon's SQS.

Batch Consumer

This component implements the Batch Consumer.
This allows you for instance to know how many messages exists in this batch and for instance let the Aggregator aggregate this number of messages.

Usage

Message headers set by the SQS producer

Header Type Description
CamelAwsSqsMD5OfBody String The MD5 checksum of the Amazon SQS message.
CamelAwsSqsMessageId String The Amazon SQS message ID.
CamelAwsSqsDelaySeconds Integer Since Camel 2.11, the delay seconds that the Amazon SQS message can be see by others.

Message headers set by the SQS consumer

Header Type Description
CamelAwsSqsMD5OfBody String The MD5 checksum of the Amazon SQS message.
CamelAwsSqsMessageId String The Amazon SQS message ID.
CamelAwsSqsReceiptHandle String The Amazon SQS message receipt handle.
CamelAwsSqsAttributes Map<String, String> The Amazon SQS message attributes.

Advanced AmazonSQS configuration

If your Camel Application is running behind a firewall or if you need to have more control over the AmazonSQS instance configuration, you can create your own instance:
AWSCredentials awsCredentials = new BasicAWSCredentials("myAccessKey", "mySecretKey");

ClientConfiguration clientConfiguration = new ClientConfiguration();
clientConfiguration.setProxyHost("http://myProxyHost");
clientConfiguration.setProxyPort(8080);

AmazonSQS client = new AmazonSQSClient(awsCredentials, clientConfiguration);

registry.bind("client", client);
and refer to it in your Camel aws-sqs component configuration:
from("aws-sqs://MyQueue?amazonSQSClient=#client&delay=5000&maxMessagesPerPoll=5")
.to("mock:result");

Dependencies

Maven users will need to add the following dependency to their pom.xml.

pom.xml

<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-aws</artifactId>
    <version>${camel-version}</version>
</dependency>

where $\{camel-version\} must be replaced by the actual version of Camel (2.6 or higher).

Chapter 9. Bean

Bean Component

The bean: component binds beans to Apache Camel message exchanges.

URI format

bean:beanID[?options]
Where beanID can be any string which is used to lookup look up the bean in the Registry

Options

Name Type Default Description
method String null The method name from the bean that will be invoked. If not provided, Camel will try to determine the method itself. In case of ambiguity an exception will be thrown. See Bean Binding for more details.
cache boolean false If enabled, Apache Camel will cache the result of the first Registry look-up. Cache can be enabled if the bean in the Registry is defined as a singleton scope.
You can append query options to the URI in the following format, ?option=value&option=value&...

Using

The object instance that is used to consume messages must be explicitly registered with the Registry. For example, if you are using Spring you must define the bean in the Spring configuration, spring.xml; or if you don't use Spring, put the bean in JNDI.
// lets populate the context with the services we need
// note that we could just use a spring.xml file to avoid this step
JndiContext context = new JndiContext();
context.bind("bye", new SayService("Good Bye!"));

CamelContext camelContext = new DefaultCamelContext(context);
Once an endpoint has been registered, you can build routes that use it to process exchanges.
// lets add simple route
camelContext.addRoutes(new RouteBuilder() {
    public void configure() {
        from("direct:hello").to("bean:bye");
    }
});
A bean: endpoint cannot be defined as the input to the route; i.e. you cannot consume from it, you can only route from some inbound message Endpoint to the bean endpoint as output. So consider using a direct: or queue: endpoint as the input.
You can use the createProxy() methods on ProxyHelper to create a proxy that will generate BeanExchanges and send them to any endpoint:
Endpoint endpoint = camelContext.getEndpoint("direct:hello");
ISay proxy = ProxyHelper.createProxy(endpoint, ISay.class);
String rc = proxy.say();
assertEquals("Good Bye!", rc);
And the same route using Spring DSL:
    <route>
       <from uri="direct:hello">
       <to uri="bean:bye"/>
    </route>

Bean as endpoint

Apache Camel also supports invoking Bean as an Endpoint. In the route below:
<camelContext xmlns="http://camel.apache.org/schema/spring">
  <route>
    <from uri="direct:start"/>
    <to uri="myBean"/>
    <to uri="mock:results"/>
  </route>
</camelContext>

<bean id="myBean" class="org.apache.camel.spring.bind.ExampleBean"/>
What happens is that when the exchange is routed to the myBean, Apache Camel will use the Bean Binding to invoke the bean. The source for the bean is just a plain POJO:
public class ExampleBean {

    public String sayHello(String name) {
        return "Hello " + name + "!";
    }
}
Apache Camel will use Bean Binding to invoke the sayHello method, by converting the Exchange's In body to the String type and storing the output of the method on the Exchange Out body.

Java DSL bean syntax

Java DSL comes with syntactic sugar for the Bean component. Instead of specifying the bean explicitly as the endpoint (i.e. to("bean:beanName")) you can use the following syntax:
// Send message to the bean endpoint
// and invoke method resolved using Bean Binding.
from("direct:start").beanRef("beanName");

// Send message to the bean endpoint
// and invoke given method.
from("direct:start").beanRef("beanName", "methodName");
Instead of passing name of the reference to the bean (so that Camel will lookup for it in the registry), you can specify the bean itself:
// Send message to the given bean instance.
from("direct:start").bean(new ExampleBean());

// Explicit selection of bean method to be invoked.
from("direct:start").bean(new ExampleBean(), "methodName");

// Camel will create the instance of bean and cache it for you.
from("direct:start").bean(ExampleBean.class);

Bean Binding

How bean methods to be invoked are chosen (if they are not specified explicitly through the method parameter) and how parameter values are constructed from the Message are all defined by the Bean Binding mechanism which is used throughout all of the various Bean Integration mechanisms in Apache Camel.

Chapter 10. Bean Validation

Bean Validation Component

Available as of Apache Camel 2.3
The Validation component performs bean validation of the message body using the Java Bean Validation API (JSR 303). Camel uses the reference implementation, which is Hibernate Validator.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-bean-validator</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

bean-validator:something[?options]
or
bean-validator://something[?options]
Where something must be present to provide a valid URL. You can append query options to the URI in the following format, ?option=value&option=value&...

URI Options

The following URI options are supported:
Option Default Description
group javax.validation.groups.Default The custom validation group to use.
messageInterpolator org.hibernate.validator.engine. ResourceBundleMessageInterpolator Reference to a custom javax.validation.MessageInterpolator in the Registry.
traversableResolver org.hibernate.validator.engine.resolver. DefaultTraversableResolver Reference to a custom javax.validation.TraversableResolver in the Registry.
constraintValidatorFactory org.hibernate.validator.engine. ConstraintValidatorFactoryImpl Reference to a custom javax.validation.ConstraintValidatorFactory in the Registry.

Example

Assumed we have a java bean with the following annotations

Car.java

// Java
public class Car {

    @NotNull
    private String manufacturer;

    @NotNull
    @Size(min = 5, max = 14, groups = OptionalChecks.class)
    private String licensePlate;
    
    // getter and setter
}
and an interface definition for our custom validation group

OptionalChecks.java

public interface OptionalChecks {
}
with the following Apache Camel route, only the @NotNull constraints on the attributes manufacturer and licensePlate will be validated (Apache Camel uses the default group javax.validation.groups.Default).
from("direct:start")
.to("bean-validator://x")
.to("mock:end")
If you want to check the constraints from the group OptionalChecks, you have to define the route like this
from("direct:start")
.to("bean-validator://x?group=OptionalChecks")
.to("mock:end")
If you want to check the constraints from both groups, you have to define a new interface first

AllChecks.java

@GroupSequence({Default.class, OptionalChecks.class})
public interface AllChecks {
}
and then your route definition should looks like this
from("direct:start")
.to("bean-validator://x?group=AllChecks")
.to("mock:end")
And if you have to provide your own message interpolator, traversable resolver and constraint validator factory, you have to write a route like this
<bean id="myMessageInterpolator" class="my.ConstraintValidatorFactory" />
<bean id="myTraversableResolver" class="my.TraversableResolver" />
<bean id="myConstraintValidatorFactory" class="my.ConstraintValidatorFactory" />

from("direct:start")
.to("bean-validator://x?group=AllChecks&messageInterpolator=#myMessageInterpolator&traversableResolver=#myTraversableResolver&constraintValidatorFactory=#myConstraintValidatorFactory")
.to("mock:end")
It's also possible to describe your constraints as XML and not as Java annotations. In this case, you have to provide the file META-INF/validation.xml which could looks like this

validation.xml

<?xml version="1.0" encoding="UTF-8"?>
<validation-config
	xmlns="http://jboss.org/xml/ns/javax/validation/configuration"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://jboss.org/xml/ns/javax/validation/configuration">
	<default-provider>org.hibernate.validator.HibernateValidator</default-provider>
	<message-interpolator>org.hibernate.validator.engine.ResourceBundleMessageInterpolator</message-interpolator>
	<traversable-resolver>org.hibernate.validator.engine.resolver.DefaultTraversableResolver</traversable-resolver>
	<constraint-validator-factory>org.hibernate.validator.engine.ConstraintValidatorFactoryImpl</constraint-validator-factory>
	
	<constraint-mapping>/constraints-car.xml</constraint-mapping>
</validation-config>
and the constraints-car.xml file

constraints-car.xml

<?xml version="1.0" encoding="UTF-8"?>
<constraint-mappings xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://jboss.org/xml/ns/javax/validation/mapping validation-mapping-1.0.xsd"
	xmlns="http://jboss.org/xml/ns/javax/validation/mapping">
	<default-package>org.apache.camel.component.bean.validator</default-package>
	
	<bean class="CarWithoutAnnotations" ignore-annotations="true">
		<field name="manufacturer">
			<constraint annotation="javax.validation.constraints.NotNull" />
		</field>
		
		<field name="licensePlate">
			<constraint annotation="javax.validation.constraints.NotNull" />
			
			<constraint annotation="javax.validation.constraints.Size">
				<groups>
					<value>org.apache.camel.component.bean.validator.OptionalChecks</value>
				</groups>
				<element name="min">5</element>
				<element name="max">14</element>
			</constraint>
		</field>
	</bean>
</constraint-mappings>

Chapter 11. Browse

Browse Component

Available as of Apache Camel 2.0
The Browse component provides a simple BrowsableEndpoint which can be useful for testing, visualisation tools or debugging. The exchanges sent to the endpoint are all available to be browsed.

URI format

browse:someName
Where someName can be any string to uniquely identify the endpoint.

Sample

In the route below, we insert a browse: component to be able to browse the Exchanges that are passing through:
  from("activemq:order.in").to("browse:orderReceived").to("bean:processOrder");
We can now inspect the received exchanges from within the Java code:
    private CamelContext context;

    public void inspectRecievedOrders() {
        BrowsableEndpoint browse = context.getEndpoint("browse:orderReceived", BrowsableEndpoint.class);
        List<Exchange> exchanges = browse.getExchanges();
        ...
        // then we can inspect the list of received exchanges from Java
        for (Exchange exchange : exchanges) {
            String payload = exchange.getIn().getBody();
            ...
        }
   }

Chapter 12. Cache

12.1. Cache Component

Available as of Camel 2.1

The cache component enables you to perform caching operations using EHCache as the Cache Implementation. The cache itself is created on demand or if a cache of that name already exists then it is simply utilized with its original settings.
This component supports producer and event based consumer endpoints.
The Cache consumer is an event based consumer and can be used to listen and respond to specific cache activities. If you need to perform selections from a pre-existing cache, use the processors defined for the cache component.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-cache</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

cache://cacheName[?options]
You can append query options to the URI in the following format, ?option=value&option=#beanRef&...

Options

The Cache component supports the following options:
Name Default Value Description
maxElementsInMemory 1000 The number of elements that may be stored in the defined cache
memoryStoreEvictionPolicy MemoryStoreEvictionPolicy.LFU
The number of elements that may be stored in the defined cache. Options include
  • MemoryStoreEvictionPolicy.LFU - Least frequently used
  • MemoryStoreEvictionPolicy.LRU - Least recently used
  • MemoryStoreEvictionPolicy.FIFO - first in first out, the oldest element by creation time
overflowToDisk true Specifies whether cache may overflow to disk
eternal false
Sets whether elements are eternal. If eternal, timeouts are ignored and the element never expires.
timeToLiveSeconds 300
The maximum time between creation time and when an element expires. Is used only if the element is not eternal
timeToIdleSeconds 300 The maximum amount of time between accesses before an element expires
diskPersistent false Whether the disk store persists between restarts of the Virtual Machine.
diskExpiryThreadIntervalSeconds 120 The number of seconds between runs of the disk expiry thread.
cacheManagerFactory null *Camel 2.8:* If you want to use a custom factory which instantiates and creates the EHCache net.sf.ehcache.CacheManager. Type: abstract org.apache.camel.component.cache.CacheManagerFactory
eventListenerRegistry null *Camel 2.8:* Sets a list of EHCache net.sf.ehcache.event.CacheEventListener for all new caches\- no need to define it per cache in EHCache xml config anymore. Type: org.apache.camel.component.cache.CacheEventListenerRegistry
cacheLoaderRegistry null *Camel 2.8:* Sets a list of org.apache.camel.component.cache.CacheLoaderWrapper that extends EHCache net.sf.ehcache.loader.CacheLoader for all new caches\- no need to define it per cache in EHCache xml config anymore. Type: org.apache.camel.component.cache.CacheLoaderRegistry
key null *Camel 2.10:* To configure using a cache key by default. If a key is provided in the message header, then the key from the header takes precedence.
operation null *Camel 2.10:* To configure using an cache operation by default. If an operation in the message header, then the operation from the header takes precedence.

Message Headers Camel 2.8\+

Header Description
CamelCacheOperation
The operation to be performed on the cache. The valid options are
  • CamelCacheGet
  • CamelCacheCheck
  • CamelCacheAdd
  • CamelCacheUpdate
  • CamelCacheDelete
  • CamelCacheDeleteAll
CamelCacheKey The cache key used to store the Message in the cache. The cache key is optional if the CamelCacheOperation is CamelCacheDeleteAll

Header changes in Camel 2.8

The header names and supported values have changed to be prefixed with 'CamelCache' and use mixed case. This makes them easier to identify and keep separate from other headers. The CacheConstants variable names remain unchanged, just their values have been changed. Also, these headers are now removed from the exchange after the cache operation is performed.
The CamelCacheAdd and CamelCacheUpdate operations support additional headers:
Header Type Description
CamelCacheTimeToLive Integer *Camel 2.11:* Time to live in seconds.
CamelCacheTimeToIdle Integer *Camel 2.11:* Time to idle in seconds.
CamelCacheEternal Boolean *Camel 2.11:* Whether the content is eternal.

Cache Producer

Sending data to the cache involves the ability to direct payloads in exchanges to be stored in a pre-existing or created-on-demand cache. The mechanics of doing this involve
  • setting the Message Exchange Headers shown above.
  • ensuring that the Message Exchange Body contains the message directed to the cache

Cache Consumer

Receiving data from the cache involves the ability of the CacheConsumer to listen on a pre-existing or created-on-demand Cache using an event Listener and receive automatic notifications when any cache activity take place (i.e CamelCacheGet/CamelCacheUpdate/CamelCacheDelete/CamelCacheDeleteAll). Upon such an activity taking place
  • an exchange containing Message Exchange Headers and a Message Exchange Body containing the just added/updated payload is placed and sent.
  • in case of a CamelCacheDeleteAll operation, the Message Exchange Header CamelCacheKey and the Message Exchange Body are not populated.

Cache Processors

There are a set of nice processors with the ability to perform cache lookups and selectively replace payload content at the
  • body
  • token
  • xpath level

Example 1: Configuring the cache

from("cache://MyApplicationCache" +
          "?maxElementsInMemory=1000" +
          "&memoryStoreEvictionPolicy=" +
              "MemoryStoreEvictionPolicy.LFU" +
          "&overflowToDisk=true" +
          "&eternal=true" +
          "&timeToLiveSeconds=300" +
          "&timeToIdleSeconds=true" +
          "&diskPersistent=true" +
          "&diskExpiryThreadIntervalSeconds=300")

Example 2: Adding keys to the cache

RouteBuilder builder = new RouteBuilder() {
    public void configure() {
     from("direct:start")
     .setHeader(CacheConstants.CACHE_OPERATION, constant(CacheConstants.CACHE_OPERATION_ADD))
     .setHeader(CacheConstants.CACHE_KEY, constant("Ralph_Waldo_Emerson"))
     .to("cache://TestCache1")
   }
};

Example 2: Updating existing keys in a cache

RouteBuilder builder = new RouteBuilder() {
    public void configure() {
     from("direct:start")
     .setHeader(CacheConstants.CACHE_OPERATION, constant(CacheConstants.CACHE_OPERATION_UPDATE))
     .setHeader(CacheConstants.CACHE_KEY, constant("Ralph_Waldo_Emerson"))
     .to("cache://TestCache1")
   }
};

Example 3: Deleting existing keys in a cache

RouteBuilder builder = new RouteBuilder() {
    public void configure() {
     from("direct:start")
     .setHeader(CacheConstants.CACHE_OPERATION, constant(CacheConstants.CACHE_DELETE))
     .setHeader(CacheConstants.CACHE_KEY", constant("Ralph_Waldo_Emerson"))
     .to("cache://TestCache1")
   }
};

Example 4: Deleting all existing keys in a cache

RouteBuilder builder = new RouteBuilder() {
    public void configure() {
     from("direct:start")
     .setHeader(CacheConstants.CACHE_OPERATION, constant(CacheConstants.CACHE_DELETEALL))
     .to("cache://TestCache1");
    }
};

Example 5: Notifying any changes registering in a Cache to Processors and other Producers

RouteBuilder builder = new RouteBuilder() {
    public void configure() {
     from("cache://TestCache1")
     .process(new Processor() {
        public void process(Exchange exchange)
               throws Exception {
           String operation = (String) exchange.getIn().getHeader(CacheConstants.CACHE_OPERATION);
           String key = (String) exchange.getIn().getHeader(CacheConstants.CACHE_KEY);
           Object body = exchange.getIn().getBody();
           // Do something
        }
     })
   }
};

Example 6: Using Processors to selectively replace payload with cache values

RouteBuilder builder = new RouteBuilder() {
   public void configure() {
     //Message Body Replacer
     from("cache://TestCache1")
     .filter(header(CacheConstants.CACHE_KEY).isEqualTo("greeting"))
     .process(new CacheBasedMessageBodyReplacer("cache://TestCache1","farewell"))
     .to("direct:next");

    //Message Token replacer
    from("cache://TestCache1")
    .filter(header(CacheConstants.CACHE_KEY).isEqualTo("quote"))
    .process(new CacheBasedTokenReplacer("cache://TestCache1","novel","#novel#"))
    .process(new CacheBasedTokenReplacer("cache://TestCache1","author","#author#"))
    .process(new CacheBasedTokenReplacer("cache://TestCache1","number","#number#"))
    .to("direct:next");

    //Message XPath replacer
    from("cache://TestCache1").
    .filter(header(CacheConstants.CACHE_KEY).isEqualTo("XML_FRAGMENT"))
    .process(new CacheBasedXPathReplacer("cache://TestCache1","book1","/books/book1"))
    .process (new CacheBasedXPathReplacer("cache://TestCache1","book2","/books/book2"))
    .to("direct:next");
   }
};

Example 7: Getting an entry from the Cache

from("direct:start")
    // Prepare headers
    .setHeader(CacheConstants.CACHE_OPERATION, constant(CacheConstants.CACHE_OPERATION_GET))
    .setHeader(CacheConstants.CACHE_KEY, constant("Ralph_Waldo_Emerson")).
    .to("cache://TestCache1").
    // Check if entry was not found
    .choice().when(header(CacheConstants.CACHE_ELEMENT_WAS_FOUND).isNull()).
        // If not found, get the payload and put it to cache
        .to("cxf:bean:someHeavyweightOperation").
        .setHeader(CacheConstants.CACHE_OPERATION, constant(CacheConstants.CACHE_OPERATION_ADD))
        .setHeader(CacheConstants.CACHE_KEY, constant("Ralph_Waldo_Emerson"))
        .to("cache://TestCache1")
    .end()
    .to("direct:nextPhase");

Example 8: Checking for an entry in the Cache

Note: The CHECK command tests existence of an entry in the cache but doesn't place a message in the body.
from("direct:start")
    // Prepare headers
    .setHeader(CacheConstants.CACHE_OPERATION, constant(CacheConstants.CACHE_OPERATION_CHECK))
    .setHeader(CacheConstants.CACHE_KEY, constant("Ralph_Waldo_Emerson")).
    .to("cache://TestCache1").
    // Check if entry was not found
    .choice().when(header(CacheConstants.CACHE_ELEMENT_WAS_FOUND).isNull()).
        // If not found, get the payload and put it to cache
        .to("cxf:bean:someHeavyweightOperation").
        .setHeader(CacheConstants.CACHE_OPERATION, constant(CacheConstants.CACHE_OPERATION_ADD))
        .setHeader(CacheConstants.CACHE_KEY, constant("Ralph_Waldo_Emerson"))
        .to("cache://TestCache1")
    .end();

Management of EHCache

EHCache has its own statistics and management from JMX.
Here's a snippet on how to expose them via JMX in a Spring application context:
<bean id="ehCacheManagementService" class="net.sf.ehcache.management.ManagementService" init-method="init" lazy-init="false">
  <constructor-arg>
    <bean class="net.sf.ehcache.CacheManager" factory-method="getInstance"/>
  </constructor-arg>
  <constructor-arg>
    <bean class="org.springframework.jmx.support.JmxUtils" factory-method="locateMBeanServer"/>
  </constructor-arg>
  <constructor-arg value="true"/>
  <constructor-arg value="true"/>
  <constructor-arg value="true"/>
  <constructor-arg value="true"/>
</bean>
Of course you can do the same thing in straight Java:
ManagementService.registerMBeans(CacheManager.getInstance(), mbeanServer, true, true, true, true);
You can get cache hits, misses, in-memory hits, disk hits, size stats this way. You can also change CacheConfiguration parameters on the fly.

Cache replication Camel 2.8\+

The Camel Cache component is able to distribute a cache across server nodes using several different replication mechanisms including: RMI, JGroups, JMS and Cache Server.
There are two different ways to make it work:
  1. You can configure ehcache.xml manually, or
  2. You can configure these three options:
    • cacheManagerFactory
    • eventListenerRegistry
    • cacheLoaderRegistry
Configuring Camel Cache replication using the first option is a bit of hard work as you have to configure all caches separately. So in a situation when the all names of caches are not known, using ehcache.xml is not a good idea.
The second option is much better when you want to use many different caches as you do not need to define options per cache. This is because replication options are set per CacheManager and per CacheEndpoint. Also it is the only way when cache names are not know at the development phase.

Note

It might be useful to read the EHCache manual to get a better understanding of the Camel Cache replication mechanism.

Example: JMS cache replication

JMS replication is the most powerful and secured replication method. Used together with Camel Cache replication makes it also rather simple. An example is available on a separate page.

12.2. cacheReplicationJMSExample

Example: JMS cache replication

Note

Please note, that this example is not finished yet. It is based on OSGi iTest instead of real life example. But no matter to that it is very good staring point for all Camel Cache Riders!
JMS replication is the most powerful and secured way. Used altogether with Camel Cache replication options is also the most easy way. This basic example is divided to few important steps that have to be made to get the cache replication to work.
The first step is to write your own implementation of CacheManagerFactory.
public class TestingCacheManagerFactory extends CacheManagerFactory {

[...]

    //This constructor is very useful when using Camel with Spring/Blueprint
    public TestingCacheManagerFactory(String xmlName, 
            TopicConnection replicationTopicConnection, Topic replicationTopic, 
            QueueConnection getQueueConnection, Queue getQueue) {
        this.xmlName = xmlName;
        this.replicationTopicConnection = replicationTopicConnection;
        this.replicationTopic = replicationTopic;
        this.getQueue = getQueue;
        this.getQueueConnection = getQueueConnection;
    }

    @Override
    protected synchronized CacheManager createCacheManagerInstance() {
        //Singleton
        if (cacheManager == null) {
            cacheManager = new WrappedCacheManager(getClass().getResourceAsStream(xmlName));
        }

        return cacheManager;
    }

    //Wrapping Ehcache's CacheManager to be able to add JMSCacheManagerPeerProvider
    public class WrappedCacheManager extends CacheManager {
        public WrappedCacheManager(InputStream xmlConfig) {
            super(xmlConfig);
            JMSCacheManagerPeerProvider jmsCMPP = new JMSCacheManagerPeerProvider(this,
                            replicationTopicConnection,
                            replicationTopic,
                            getQueueConnection,
                            getQueue,
                            AcknowledgementMode.AUTO_ACKNOWLEDGE,
                            true);
            cacheManagerPeerProviders.put(jmsCMPP.getScheme(), jmsCMPP);
            jmsCMPP.init();
        }
    }
}
Next step is to write your own implementation of CacheLoaderWrapper, the easiest one is:
public class WrappedJMSCacheLoader implements CacheLoaderWrapper {

[...]

    //This constructor is very useful when using Camel with Spring/Blueprint
    public WrappedJMSCacheLoader(QueueConnection getQueueConnection,
            Queue getQueue, AcknowledgementMode acknowledgementMode,
            int timeoutMillis) {
        this.getQueueConnection = getQueueConnection;
        this.getQueue = getQueue;
        this.acknowledgementMode = acknowledgementMode;
        this.timeoutMillis = timeoutMillis;
    }

    @Override
    public void init(Ehcache cache) {
        jmsCacheLoader = new JMSCacheLoader(cache, defaultLoaderArgument,
                getQueueConnection, getQueue, acknowledgementMode,
                timeoutMillis);
    }

    @Override
    public CacheLoader clone(Ehcache arg0) throws CloneNotSupportedException {
        return jmsCacheLoader.clone(arg0);
    }

    @Override
    public void dispose() throws CacheException {
        jmsCacheLoader.dispose();
    }

[...]

}
At the third step you can take care about Camel Cache options (prepare their values):
  • cacheManagerFactory
  • eventListenerRegistry
  • cacheLoaderRegistry
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:camel="http://camel.apache.org/schema/spring"
       xsi:schemaLocation="
       http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
       http://camel.apache.org/schema/spring http://camel.apache.org/schema/spring/camel-spring.xsd">

    <bean id="queueConnection1" factory-bean="amqCF" factory-method="createQueueConnection" class="javax.jms.QueueConnection" />
    <bean id="topicConnection1" factory-bean="amqCF" factory-method="createTopicConnection" class="javax.jms.TopicConnection" />
    <bean id="queue1" class="org.apache.activemq.command.ActiveMQQueue">
        <constructor-arg ref="getQueue" />
    </bean>
    <bean id="topic1" class="org.apache.activemq.command.ActiveMQTopic">
        <constructor-arg ref="getTopic" />
    </bean>

    <bean id="jmsListener1" class="net.sf.ehcache.distribution.jms.JMSCacheReplicator">
        <constructor-arg index="0" value="true" />
        <constructor-arg index="1" value="true" />
        <constructor-arg index="2" value="true" />
        <constructor-arg index="3" value="true" />
        <constructor-arg index="4" value="false" />
        <constructor-arg index="5" value="0" />
    </bean>

    <bean id="jmsLoader1" class="my.cache.replication.WrappedJMSCacheLoader">
        <constructor-arg index="0" ref="queueConnection1" />
        <constructor-arg index="1" ref="queue1" />
        <constructor-arg index="2" value="AUTO_ACKNOWLEDGE" />
        <constructor-arg index="3" value="30000" />
    </bean>

    <bean id="cacheManagerFactory1" class="my.cache.replication.TestingCacheManagerFactory">
        <constructor-arg index="0" value="ehcache_jms_test.xml" />
        <constructor-arg index="1" ref="topicConnection1" />
        <constructor-arg index="2" ref="topic1" />
        <constructor-arg index="3" ref="queueConnection1" />
        <constructor-arg index="4" ref="queue1" />
    </bean>

    <bean id="eventListenerRegistry1" class="org.apache.camel.component.cache.CacheEventListenerRegistry">
        <constructor-arg>
            <list>
                <ref bean="jmsListener1" />
            </list>
        </constructor-arg>
    </bean>

    <bean id="cacheLoaderRegistry1" class="org.apache.camel.component.cache.CacheLoaderRegistry">
        <constructor-arg>
            <list>
                <ref bean="jmsLoader1"/>
            </list>
        </constructor-arg>
    </bean>
</beans>
The final step is to define some routes using Cache component
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:camel="http://camel.apache.org/schema/spring"
       xsi:schemaLocation="
       http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
       http://camel.apache.org/schema/spring http://camel.apache.org/schema/spring/camel-spring.xsd">

    <bean id="getQueue" class="java.lang.String">
        <constructor-arg value="replicationGetQueue" />
    </bean>

    <bean id="getTopic" class="java.lang.String">
        <constructor-arg value="replicationTopic" />
    </bean>

    <!-- Import the xml file explained at step three -->
    <import resource="JMSReplicationCache1.xml"/>

    <camelContext xmlns="http://camel.apache.org/schema/spring">
        <camel:endpoint id="fooCache1" uri="cache:foo?cacheManagerFactory=#cacheManagerFactory1&ventListenerRegistry=#eventListenerRegistry1&acheLoaderRegistry=#cacheLoaderRegistry1"/>

        <camel:route>
            <camel:from uri="direct:addRoute"/>
            <camel:setHeader headerName="CamelCacheOperation">
                <camel:constant>CamelCacheAdd</camel:constant>
            </camel:setHeader>
            <camel:setHeader headerName="CamelCacheKey">
                <camel:constant>foo</camel:constant>
            </camel:setHeader>
            <camel:to ref="fooCache1"/>
        </camel:route>

    </camelContext>

    <bean id="amqCF" class="org.apache.activemq.ActiveMQConnectionFactory">
        <property name="brokerURL" value="vm://localhost?broker.persistent=false"/>
    </bean>

    <bean id="activemq" class="org.apache.camel.component.jms.JmsComponent">
        <property name="connectionFactory">
            <ref bean="amqCF"/>
        </property>
    </bean>

</beans>

Chapter 13. CDI

Camel CDI

As of 2.10 we now have support Contexts and Dependency Injection - JSR299 and Dependency Injection for Java - JSR330 as a dependency injection framework. This offers new opportunities to develop and deploy Apache Camel projects in Java EE 6 containers but also in standalone Java SE or CDI container
The current project is under active development and does not provide all the features that we have with injection frameworks like Spring or Blueprint

Dependency Injecting Camel with CDI

Basically, two things should be done to use Apache Camel in a CDI environment. First, we just need to create a BootStrap class which will be use by the Java EE 6 container or Java SE to start the Camel Context. The CdiCamelContext when instantiated will add a CDI Bean Registry. That will allow Camel to perform lookup of beans injected and registered in CDI container. Next, we must add CDI annotated beans (@inject, @named, ...) to use them from the Apache Camel routes.

Bootstrapping Camel with CDI container

The following example shows how we can bootstrap an Apache Camel Context in a Boot Strap class. This class contains important annotations like the javax.ejb.Singleton. This annotation will tell the container to create a Singleton instance of the BootStrapClass class. This mechanism is similar to Bean instance creation that we have with Spring framework. By combining this annotation with javax.ejb.Startup, the container will start the camel context at the startup of the CDI container.
    @Singleton
    @Startup
    public class BootStrap {
    ...
When the @PreConstruct annotation is called, then we inject a CdiCamelContext objet, register a SimpleCamelRoute using @Inject annotation and starts the Camel Route.
    @PostConstruct
    public void init() throws Exception {
            logger.info(">> Create CamelContext and register Camel Route.");

            // Define Timer URI
            simpleRoute.setTimerUri("timer://simple?fixedRate=true&period=10s");

            // Add Camel Route
            camelCtx.addRoutes(simpleRoute);

            // Start Camel Context
            camelCtx.start();
When you look to the following Camel Route code, you can see that we do a lookup to find a bean "helloWorld" which has been injected. This is possible because the CdiCamelContext registers a Camel Registry containing a reference to a CDI BeanManager.
    @Override
    public void configure() throws Exception {

        from(timerUri)
            .setBody()
                .simple("Bean Injected")

            // Lookup for bean injected by CDI container
            // The HellowWorld class is annotated using @Named
            .beanRef("helloWorld", "sayHello")

            .log(">> Response : ${body}");

    }
Here is the code of the HelloWorld Bean
@Named
public class HelloWorld {

    public String sayHello(@Body String message) {
        return ">> Hello " + message + " user.";
    }
}
This project is started using the GlassFish maven plugin but alternatively, you can deploy the war file produced in any Java EE 6 servers : Glassfish, JBoss AS 7, OpenEJB, Apache TomEE or Apache KarafEE or using a Java SE.

See Also

Chapter 14. Class

Class Component

Available as of Apache Camel 2.4
The class: component binds beans to message exchanges. It works in the same way as the Bean component but instead of looking up beans from a Registry it creates the bean based on the class name.

URI format

class:className[?options]
Where className is the fully qualified class name to create and use as bean.

Options

Name Type Default Description
method String null The method name that bean will be invoked. If not provided, Apache Camel will try to pick the method itself. In case of ambiguity an exception is thrown. See Bean Binding for more details.
multiParameterArray boolean false How to treat the parameters which are passed from the message body; if it is true, the In message body should be an array of parameters.
You can append query options to the URI in the following format, ?option=value&option=value&...

Using

You simply use the class component just as the Bean component but by specifying the fully qualified classname instead. For example to use the MyFooBean you have to do as follows:
from("direct:start").to("class:org.apache.camel.component.bean.MyFooBean").to("mock:result");
You can also specify which method to invoke on the MyFooBean, for example hello:
from("direct:start").to("class:org.apache.camel.component.bean.MyFooBean?method=hello").to("mock:result");

Setting properties on the created instance

In the endpoint uri you can specify properties to set on the created instance, for example if it has a setPrefix method:
from("direct:start")
    .to("class:org.apache.camel.component.bean.MyPrefixBean?prefix=Bye")
    .to("mock:result");
And you can also use the # syntax to refer to properties to be looked up in the Registry.
from("direct:start")
    .to("class:org.apache.camel.component.bean.MyPrefixBean?cool=#foo")
    .to("mock:result");
Which will lookup a bean from the Registry with the id foo and invoke the setCool method on the created instance of the MyPrefixBean class.

Note

See more details at the Bean component as the class component works in much the same way.

Chapter 15. CMIS

CMIS Component

Available as of Camel 2.11 The cmis component uses the Apache Chemistry client API and allows you to add/read nodes to/from a CMIS compliant content repositories.

URI Format

cmis://cmisServerUrl[?options]
You can append query options to the URI in the following format, ?options=value&option2=value&...

URI Options

Name Default Value Context Description
queryMode false Producer If true, will execute the cmis query from the message body and return result, otherwise will create a node in the cmis repository
query String Consumer The cmis query to execute against the repository. If not specified, the consumer will retrieve every node from the content repository by iterating the content tree recursively
username null Both Username for the cmis repository
password null Both Password for the cmis repository
repositoryId null Both The Id of the repository to use. If not specified the first available repository is used
pageSize 100 Both Number of nodes to retrieve per page
readCount 0 Both Max number of nodes to read
readContent false Both If set to true, the content of document node will be retrieved in addition to the properties

Usage

Message headers evaluated by the producer

Header Default Value Description
CamelCMISFolderPath / The current folder to use during the execution. If not specified will use the root folder
CamelCMISRetrieveContent false In queryMode this header will force the producer to retrieve the content of document nodes.
CamelCMISReadSize 0 Max number of nodes to read.
cmis:path null If CamelCMISFolderPath is not set, will try to find out the path of the node from this cmis property and it is name
cmis:name null If CamelCMISFolderPath is not set, will try to find out the path of the node from this cmis property and it is path
cmis:objectTypeId null The type of the node
cmis:contentStreamMimeType null The mimetype to set for a document

Message headers set during querying Producer operation

Header Type Description
CamelCMISResultCount Integer Number of nodes returned from the query.

pom.xml

<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-cmis</artifactId>
    <version>${camel-version}</version>
</dependency>
where ${camel-version} must be replaced by the actual version of Camel (2.11 or higher).

Chapter 16. Cometd

Cometd Component

The cometd: component is a transport for working with the jetty implementation of the cometd/bayeux protocol. Using this component in combination with the dojo toolkit library it's possible to push Apache Camel messages directly into the browser using an AJAX based mechanism.

URI format

cometd://host:port/channelName[?options]
The channelName represents a topic that can be subscribed to by the Apache Camel endpoints.

Examples

cometd://localhost:8080/service/mychannel
cometds://localhost:8443/service/mychannel
where cometds: represents an SSL configured endpoint.

Options

Name Default Value Description
resourceBase The root directory for the web resources or classpath. Use the protocol file: or classpath: depending if you want that the component loads the resource from file system or classpath. Classpath is required for OSGI deployment where the resources are packaged in the jar
baseResource Camel 2.7: The root directory for the web resources or classpath. Use the protocol file: or classpath: depending if you want that the component loads the resource from file system or classpath. Classpath is required for OSGI deployment where the resources are packaged in the jar
timeout 240000 The server side poll timeout in milliseconds. This is how long the server will hold a reconnect request before responding.
interval 0 The client side poll timeout in milliseconds. How long a client will wait between reconnects
maxInterval 30000 The max client side poll timeout in milliseconds. A client will be removed if a connection is not received in this time.
multiFrameInterval 1500 The client side poll timeout, if multiple connections are detected from the same browser.
jsonCommented true If true, the server will accept JSON wrapped in a comment and will generate JSON wrapped in a comment. This is a defence against Ajax Hijacking.
logLevel 1 0=none, 1=info, 2=debug.
sslContextParameters Camel 2.9: Reference to a org.apache.camel.util.jsse.SSLContextParameters in the Registry. This reference overrides any configured SSLContextParameters at the component level. See Using the JSSE Configuration Utility.
crossOriginFilterOn false Camel 2.10: If true, the server will support for cross-domain filtering
allowedOrigins * Camel 2.10: The origins domain that support to cross, if the crosssOriginFilterOn is true
filterPath Camel 2.10: The filterPath will be used by the CrossOriginFilter, if the crosssOriginFilterOn is true
disconnectLocalSession true Camel 2.10.5/2.11.1: (Producer only): Whether to disconnect local sessions after publishing a message to its channel. Disconnecting local session is needed as they are not swept by default by CometD, and therefore you can run out of memory.
You can append query options to the URI in the following format, ?option=value&option=value&...
Here is some examples of how to pass the parameters.
For file (when the Webapp resources are located in the Web Application directory) cometd://localhost:8080?resourceBase=file./webapp. For classpath (when the web resources are packaged inside the Webapp folder) cometd://localhost:8080?resourceBase=classpath:webapp.

Authentication

Available as of Camel 2.8
You can configure custom SecurityPolicy and Extension's to the CometdComponent which allows you to use authentication as documented here

Setting up SSL for Cometd Component

Using the JSSE Configuration Utility

As of Camel 2.9, the Cometd component supports SSL/TLS configuration through the Camel JSSE Configuration Utility. This utility greatly decreases the amount of component specific code you need to write and is configurable at the endpoint and component levels. The following examples demonstrate how to use the utility with the Cometd component.

Programmatic configuration of the component

KeyStoreParameters ksp = new KeyStoreParameters();
ksp.setResource("/users/home/server/keystore.jks");
ksp.setPassword("keystorePassword");

KeyManagersParameters kmp = new KeyManagersParameters();
kmp.setKeyStore(ksp);
kmp.setKeyPassword("keyPassword");

TrustManagersParameters tmp = new TrustManagersParameters();
tmp.setKeyStore(ksp);

SSLContextParameters scp = new SSLContextParameters();
scp.setKeyManagers(kmp);
scp.setTrustManagers(tmp);

CometdComponent commetdComponent = getContext().getComponent("cometds", CometdComponent.class);
commetdComponent.setSslContextParameters(scp);

Spring DSL based configuration of endpoint

...
  <camel:sslContextParameters
      id="sslContextParameters">
    <camel:keyManagers
        keyPassword="keyPassword">
      <camel:keyStore
          resource="/users/home/server/keystore.jks"
          password="keystorePassword"/>
    </camel:keyManagers>
    <camel:trustManagers>
      <camel:keyStore
          resource="/users/home/server/keystore.jks"
          password="keystorePassword"/>
    </camel:keyManagers>
  </camel:sslContextParameters>...
...
  <to uri="cometds://127.0.0.1:443/service/test?baseResource=file:./target/test-classes/webapp&timeout=240000&interval=0&maxInterval=30000&multiFrameInterval=1500&jsonCommented=true&logLevel=2&sslContextParameters=#sslContextParameters"/>...

Chapter 17. Context

Context Component

Available as of Camel 2.7
The context component allows you to create new Camel Components from a CamelContext with a number of routes which is then treated as a black box, allowing you to refer to the local endpoints within the component from other CamelContexts.
It is similar to the Routebox component in idea, though the Context component tries to be really simple for end users; just a simple convention over configuration approach to refer to local endpoints inside the CamelContext Component.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-context</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

context:camelContextId:localEndpointName[?options]

Or you can omit the "context:" prefix.
camelContextId:localEndpointName[?options]

  • camelContextId is the ID you used to register the CamelContext into the Registry.
  • localEndpointName can be a valid Camel URI evaluated within the black box CamelContext. Or it can be a logical name which is mapped to any local endpoints. For example if you locally have endpoints like direct:invoices and seda:purchaseOrders inside a CamelContext of id supplyChain, then you can just use the URIs supplyChain:invoices or supplyChain:purchaseOrders to omit the physical endpoint kind and use pure logical URIs.
You can append query options to the URI in the following format, ?option=value&option=value&...

Example

In this example we'll create a black box context, then we'll use it from another CamelContext.

Defining the context component

First you need to create a CamelContext, add some routes in it, start it and then register the CamelContext into the Registry (JNDI, Spring, Guice or OSGi etc).
This can be done in the usual Camel way from this test case (see the createRegistry() method); this example shows Java and JNDI being used...
// lets create our black box as a camel context and a set of routes
DefaultCamelContext blackBox = new DefaultCamelContext(registry);
blackBox.setName("blackBox");
blackBox.addRoutes(new RouteBuilder() {
    @Override
    public void configure() throws Exception {
        // receive purchase orders, lets process it in some way then send an invoice
        // to our invoice endpoint
        from("direct:purchaseOrder").
          setHeader("received").constant("true").
          to("direct:invoice");
    }
});
blackBox.start();

registry.bind("accounts", blackBox);

Notice in the above route we are using pure local endpoints (direct and seda). Also note we expose this CamelContext using the accounts ID. We can do the same thing in Spring via
<camelContext id="accounts" xmlns="http://camel.apache.org/schema/spring">
  <route> 
    <from uri="direct:purchaseOrder"/>
    ...
    <to uri="direct:invoice"/>
  </route>
</camelContext>

Using the context component

Then in another CamelContext we can then refer to this "accounts black box" by just sending to accounts:purchaseOrder and consuming from accounts:invoice.
If you prefer to be more verbose and explicit you could use context:accounts:purchaseOrder or even context:accounts:direct://purchaseOrder if you prefer. But using logical endpoint URIs is preferred as it hides the implementation detail and provides a simple logical naming scheme.
For example if we wish to then expose this accounts black box on some middleware (outside of the black box) we can do things like...
<camelContext xmlns="http://camel.apache.org/schema/spring">
  <route> 
    <!-- consume from an ActiveMQ into the black box -->
    <from uri="activemq:Accounts.PurchaseOrders"/>
    <to uri="accounts:purchaseOrders"/>
  </route>
  <route> 
    <!-- lets send invoices from the black box to a different ActiveMQ Queue -->
    <from uri="accounts:invoice"/>
    <to uri="activemq:UK.Accounts.Invoices"/>
  </route>
</camelContext>

Naming endpoints

A context component instance can have many public input and output endpoints that can be accessed from outside it's CamelContext. When there are many it is recommended that you use logical names for them to hide the middleware as shown above.
However when there is only one input, output or error/dead letter endpoint in a component we recommend using the common posix shell names in, out and err

Chapter 18. ControlBus Component

ControlBus Component

Available as of Camel 2.11
The controlbus: component provides easy management of Camel applications based on the Control Bus EIP pattern. For example, by sending a message to an Endpoint you can control the lifecycle of routes, or gather performance statistics.
controlbus:command[?options]
Where command can be any string to identify which type of command to use.

Commands

Command Description
route To control routes using the routeId and action parameter.
language Allows you to specify a Language to use for evaluating the message body. If there is any result from the evaluation, then the result is put in the message body.

Options

Name Default Value Description
routeId null To specify a route by its id.
action null To denote an action that can be either: start, stop, or status. To either start or stop a route, or to get the status of the route as output in the message body. You can use suspend and resume from Camel 2.11.1 onwards to either suspend or resume a route. And from Camel 2.11.1 onwards you can use stats to get performance statics returned in XML format; the routeId option can be used to define which route to get the performance stats for, if routeId is not defined, then you get statistics for the entire CamelContext.
async false Whether to execute the control bus task asynchronously. Important: If this option is enabled, then any result from the task is not set on the Exchange. This is only possible if executing tasks synchronously.
loggingLevel INFO Logging level used for logging when task is done, or if any exceptions occurred during processing the task.
You can append query options to the URI in the following format, ?option=value&option=value&...

Samples

Using route command

The route command allows you to do common tasks on a given route very easily, for example to start a route, you can send an empty message to this endpoint:
template.sendBody("controlbus:route?routeId=foo&action=start", null);
To get the status of the route, you can do:
String status = template.requestBody("controlbus:route?routeId=foo&action=status", null, String.class);

Getting performance statistics

Available as of Camel 2.11.1
This requires JMX to be enabled (is by default) then you can get the performance statics per route, or for the CamelContext. For example to get the statics for a route named foo, we can do:
String xml = template.requestBody("controlbus:route?routeId=foo&action=stats", null, String.class);
The returned statics is in XML format. Its the same data you can get from JMX with the dumpRouteStatsAsXml operation on the ManagedRouteMBean.
To get statics for the entire CamelContext you just omit the routeId parameter as shown below:
String xml = template.requestBody("controlbus:route?action=stats", null, String.class);

Using Simple language

You can use the Simple language with the control bus, for example to stop a specific route, you can send a message to the "controlbus:language:simple" endpoint containing the following message:
template.sendBody("controlbus:language:simple", "${camelContext.stopRoute('myRoute')}");
As this is a void operation, no result is returned. However, if you want the route status you can do:
String status = template.requestBody("controlbus:language:simple", "${camelContext.getRouteStatus('myRoute')}", String.class);
Notice: its easier to use the route command to control lifecycle of routes. The language command allows you to execute a language script that has stronger powers such as Groovy or to some extend the Simple language.
For example to shutdown Camel itself you can do:
template.sendBody("controlbus:language:simple?async=true", "${camelContext.stop()}");
Notice we use async=true to stop Camel asynchronously as otherwise we would be trying to stop Camel while it was in-flight processing the message we sent to the control bus component.

Note

You can also use other languages such as Groovy, etc.

Chapter 19. CouchDB

Camel CouchDB component

Available as of Camel 2.11
The couchdb: component allows you to treat CouchDB instances as a producer or consumer of messages. Using the lightweight LightCouch API, this camel component has the following features:
  • As a consumer, monitors couch changesets for inserts, updates and deletes and publishes these as messages into camel routes.
  • As a producer, can save or update documents into couch.
  • Can support as many endpoints as required, eg for multiple databases across multiple instances.
  • Ability to have events trigger for only deletes, only inserts/updates or all (default).
  • Headers set for sequenceId, document revision, document id, and HTTP method type.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-couchdb</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

couchdb:http://hostname[:port]/database?[options]
Where hostname is the hostname of the running couchdb instance. Port is optional and if not specified then defaults to 5984.

Options

Property Default Description
deletes true document deletes are published as events
updates true document inserts/updates are published as events
heartbeat 30000 how often to send an empty message to keep socket alive in millis
createDatabase true create the database if it does not already exist
username null username in case of authenticated databases
password null password for authenticated databases

Headers

The following headers are set on exchanges during message transport.
Property Value
CouchDbDatabase the database the message came from
CouchDbSeq the couchdb changeset sequence number of the update / delete message
CouchDbId the couchdb document id
CouchDbRev the couchdb document revision
CouchDbMethod the method (delete / update)
Headers are set by the consumer once the message is received. The producer will also set the headers for downstream processors once the insert/update has taken place. Any headers set prior to the producer are ignored. That means for example, if you set CouchDbId as a header, it will not be used as the id for insertion, the id of the document will still be used.

Message Body

The component will use the message body as the document to be inserted. If the body is an instance of String, then it will be marshalled into a GSON object before insert. This means that the string must be valid JSON or the insert / update will fail. If the body is an instance of a com.google.gson.JsonElement then it will be inserted as is. Otherwise the producer will throw an exception of unsupported body type.

Samples

For example if you wish to consume all inserts, updates and deletes from a CouchDB instance running locally, on port 9999 then you could use the following:
from("couchdb:http://localhost:9999").process(someProcessor);
If you were only interested in deletes, then you could use the following
from("couchdb:http://localhost:9999?updates=false").process(someProcessor);
If you wanted to insert a message as a document, then the body of the exchange is used
from("someProducingEndpoint").process(someProcessor).to("couchdb:http://localhost:9999")

Chapter 20. Crypto (Digital Signatures)

Crypto component for Digital Signatures

Available as of Apache Camel 2.3
Using Apache Camel cryptographic endpoints and Java's Cryptographic extension it is easy to create Digital Signatures for Exchanges. Apache Camel provides a pair of flexible endpoints which get used in concert to create a signature for an exchange in one part of the exchange's workflow and then verify the signature in a later part of the workflow.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-crypto</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

Introduction

Digital signatures make use Asymmetric Cryptographic techniques to sign messages. From a (very) high level, the algorithms use pairs of complimentary keys with the special property that data encrypted with one key can only be decrypted with the other. One, the private key, is closely guarded and used to 'sign' the message while the other, public key, is shared around to anyone interested in verifying your messages. Messages are signed by encrypting a digest of the message with the private key. This encrypted digest is transmitted along with the message. On the other side the verifier recalculates the message digest and uses the public key to decrypt the the digest in the signature. If both digest match the verifier knows only the holder of the private key could have created the signature.
Apache Camel uses the Signature service from the Java Cryptographic Extension to do all the heavy cryptographic lifting required to create exchange signatures. The following are some excellent sources for explaining the mechanics of Cryptography, Message digests and Digital Signatures and how to leverage them with the JCE.
  • Bruce Schneier's Applied Cryptography
  • Beginning Cryptography with Java by David Hook
  • The ever insightful, Wikipedia Digital_signatures

URI format

As mentioned Apache Camel provides a pair of crypto endpoints to create and verify signatures
crypto:sign:name[?options]
crypto:verify:name[?options]
  • crypto:sign creates the signature and stores it in the Header keyed by the constant Exchange.SIGNATURE, i.e. "CamelDigitalSignature".
  • crypto:verify will read in the contents of this header and do the verification calculation.
In order to correctly function, sign and verify need to share a pair of keys, sign requiring a PrivateKey and verify a PublicKey (or a Certificate containing one). Using the JCE is is very simple to generate these key pairs but it is usually most secure to use a KeyStore to house and share your keys. The DSL is very flexible about how keys are supplied and provides a number of mechanisms.
Note a crypto:sign endpoint is typically defined in one route and the complimentary crypto:verify in another, though for simplicity in the examples they appear one after the other. It goes without saying that both sign and verify should be configured identically.

Options

Name Type Default Description
algorithm String DSA The name of the JCE Signature algorithm that will be used.
alias String null An alias name that will be used to select a key from the keystore.
bufferSize Integer 2048 the size of the buffer used in the signature process.
certificate Certificate null A Certificate used to verify the signature of the exchange's payload. Either this or a Public Key is required.
keystore KeyStore null A reference to a JCE Keystore that stores keys and certificates used to sign and verify.
provider String null The name of the JCE Security Provider that should be used.
privateKey PrivatKey null The private key used to sign the exchange's payload.
publicKey PublicKey null The public key used to verify the signature of the exchange's payload.
secureRandom secureRandom null A reference to a SecureRandom object that wil lbe used to initialize the Signature service.
password char[] null The password for the keystore.
clearHeaders String true Remove camel crypto headers from Message after a verify operation (value can be "true"/{{"false"}}).

1) Raw keys

The most basic way to way to sign and verify an exchange is with a KeyPair as follows.
from("direct:keypair").to("crypto:sign://basic?privateKey=#myPrivateKey", "crypto:verify://basic?publicKey=#myPublicKey", "mock:result");
The same can be achieved with the Spring XML Extensions using references to keys
<route>
    <from uri="direct:keypair"/>
    <to uri="crypto:sign://basic?privateKey=#myPrivateKey" />
    <to uri="crypto:verify://basic?publicKey=#myPublicKey" />
    <to uri="mock:result"/>
</route>

2) KeyStores and Aliases.

The JCE provides a very versatile KeyStore for housing pairs of PrivateKeys and Certificates keeping them encrypted and password protected. They can be retrieved from it by applying an alias to the retrieval apis. There are a number of ways to get keys and Certificates into a keystore most often this is done with the external 'keytool' application. This is a good example of using keytool to create a KeyStore with a self signed Cert and Private key.
The examples use a Keystore with a key and cert aliased by 'bob'. The password for the keystore and the key is 'letmein'
The following shows how to use a Keystore via the Fluent builders, it also shows how to load and initialize the keystore.
from("direct:keystore").to("crypto:sign://keystore?keystore=#keystore&alias=bob&password=letmein", "crypto:verify://keystore?keystore=#keystore&alias=bob", "mock:result");
Again in Spring a ref is used to lookup an actual keystore instance.
<route>
    <from uri="direct:keystore"/>
    <to uri="crypto:sign://keystore?keystore=#keystore&lias=bob&assword=letmein" />
    <to uri="crypto:verify://keystore?keystore=#keystore&lias=bob" />
    <to uri="mock:result"/>
</route>

3) Changing JCE Provider and Algorithm

Changing the Signature algorithm or the Security provider is a simple matter of specifying their names. You will need to also use Keys that are compatible with the algorithm you choose.
KeyPairGenerator keyGen = KeyPairGenerator.getInstance("RSA");
keyGen.initialize(512, new SecureRandom());
keyPair = keyGen.generateKeyPair();
PrivateKey privateKey = keyPair.getPrivate();
PublicKey publicKey = keyPair.getPublic();

// we can set the keys explicitly on the endpoint instances.
context.getEndpoint("crypto:sign://rsa?algorithm=MD5withRSA", DigitalSignatureEndpoint.class).setPrivateKey(privateKey);
context.getEndpoint("crypto:verify://rsa?algorithm=MD5withRSA", DigitalSignatureEndpoint.class).setPublicKey(publicKey);
from("direct:algorithm").to("crypto:sign://rsa?algorithm=MD5withRSA", "crypto:verify://rsa?algorithm=MD5withRSA", "mock:result");
from("direct:provider").to("crypto:sign://provider?privateKey=#myPrivateKey&provider=SUN", "crypto:verify://provider?publicKey=#myPublicKey&provider=SUN", "mock:result");
or
<route>
    <from uri="direct:algorithm"/>
    <to uri="crypto:sign://rsa?algorithm=MD5withRSA&rivateKey=#rsaPrivateKey" />
    <to uri="crypto:verify://rsa?algorithm=MD5withRSA&ublicKey=#rsaPublicKey" />
    <to uri="mock:result"/>
</route>
<route>
    <from uri="direct:provider"/>
    <to uri="crypto:sign://provider?privateKey=#myPrivateKey&rovider=SUN" />
    <to uri="crypto:verify://provider?publicKey=#myPublicKey&rovider=SUN" />
    <to uri="mock:result"/>
</route>

4) Changing the Signature Mesasge Header

It may be desirable to change the message header used to store the signature. A different header name can be specified in the route definition as follows
from("direct:signature-header").to("crypto:sign://another?privateKey=#myPrivateKey&signatureHeader=AnotherDigitalSignature",
                                   "crypto:verify://another?publicKey=#myPublicKey&signatureHeader=AnotherDigitalSignature", "mock:result");
or
<route>
    <from uri="direct:signature-header"/>
    <to uri="crypto:sign://another?privateKey=#myPrivateKey&ignatureHeader=AnotherDigitalSignature" />
    <to uri="crypto:verify://another?publicKey=#myPublicKey&ignatureHeader=AnotherDigitalSignature" />
    <to uri="mock:result"/>
</route>

5) Changing the buffersize

In case you need to update the size of the buffer...
from("direct:buffersize").to("crypto:sign://buffer?privateKey=#myPrivateKey&buffersize=1024", "crypto:verify://buffer?publicKey=#myPublicKey&buffersize=1024", "mock:result");
or
<route>
    <from uri="direct:buffersize" />
    <to uri="crypto:sign://buffer?privateKey=#myPrivateKey&uffersize=1024" />
    <to uri="crypto:verify://buffer?publicKey=#myPublicKey&uffersize=1024" />
    <to uri="mock:result"/>
</route>

6) Supplying Keys dynamically.

When using a Recipient list or similar EIP the recipient of an exchange can vary dynamically. Using the same key across all recipients may neither be feasible or desirable. It would be useful to be able to specify the signature keys dynamically on a per exchange basis. The exchange could then be dynamically enriched with the key of its target recipient prior to signing. To facilitate this the signature mechanisms allow for keys to be supplied dynamically via the message headers below
  • Exchange.SIGNATURE_PRIVATE_KEY, "CamelSignaturePrivateKey"
  • Exchange.SIGNATURE_PUBLIC_KEY_OR_CERT, "CamelSignaturePublicKeyOrCert"
from("direct:headerkey-sign").to("crypto:sign://alias");
from("direct:headerkey-verify").to("crypto:verify://alias", "mock:result");
or
<route>
    <from uri="direct:headerkey-sign"/>
    <to uri="crypto:sign://headerkey" />
</route>       
<route>
    <from uri="direct:headerkey-verify"/>
    <to uri="crypto:verify://headerkey" />
    <to uri="mock:result"/>
</route>
Better again would be to dynamically supply a keystore alias. Again the alias can be supplied in a message header
  • Exchange.KEYSTORE_ALIAS, "CamelSignatureKeyStoreAlias"
from("direct:alias-sign").to("crypto:sign://alias?keystore=#keystore");
from("direct:alias-verify").to("crypto:verify://alias?keystore=#keystore", "mock:result");
or
<route>
    <from uri="direct:alias-sign"/>
    <to uri="crypto:sign://alias?keystore=#keystore" />
</route>       
<route>
    <from uri="direct:alias-verify"/>
    <to uri="crypto:verify://alias?keystore=#keystore" />
    <to uri="mock:result"/>
</route>
The header would be set as follows
Exchange unsigned = getMandatoryEndpoint("direct:alias-sign").createExchange();
unsigned.getIn().setBody(payload);
unsigned.getIn().setHeader(DigitalSignatureConstants.KEYSTORE_ALIAS, "bob");
unsigned.getIn().setHeader(DigitalSignatureConstants.KEYSTORE_PASSWORD, "letmein".toCharArray());
template.send("direct:alias-sign", unsigned);
Exchange signed = getMandatoryEndpoint("direct:alias-sign").createExchange();
signed.getIn().copyFrom(unsigned.getOut());
signed.getIn().setHeader(KEYSTORE_ALIAS, "bob");
template.send("direct:alias-verify", signed);
See also:

Chapter 21. CXF

CXF Component

The cxf: component provides integration with Apache CXF for connecting to JAX-WS services hosted in CXF.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-cxf</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

Note

If you want to learn about CXF dependencies, see the WHICH-JARS text file.

Note

When using CXF as a consumer, the CAMEL:CXF Bean Component allows you to factor out how message payloads are received from their processing as a RESTful or SOAP web service. This has the potential of using a multitude of transports to consume web services. The bean component's configuration is also simpler and provides the fastest method to implement web services using Camel and CXF.

Note

When using CXF in streaming modes (see DataFormat option), then also read about Stream caching.

URI format

cxf:bean:cxfEndpoint[?options]
Where cxfEndpoint represents a bean ID that references a bean in the Spring bean registry. With this URI format, most of the endpoint details are specified in the bean definition.
cxf://someAddress[?options]
Where someAddress specifies the CXF endpoint's address. With this URI format, most of the endpoint details are specified using options.
For either style above, you can append options to the URI as follows:
cxf:bean:cxfEndpoint?wsdlURL=wsdl/hello_world.wsdl&dataFormat=PAYLOAD

Options

Name Required Description
wsdlURL No
The location of the WSDL. WSDL is obtained from endpoint address by default. For example:
file://local/wsdl/hello.wsdl or wsdl/hello.wsdl
serviceClass Yes
The name of the SEI (Service Endpoint Interface) class. This class can have, but does not require, JSR181 annotations.  Since 2.0, this option is only required by POJO mode. If the wsdlURL option is provided, serviceClass is not required for PAYLOAD and MESSAGE mode. When wsdlURL option is used without serviceClass, the serviceName and portName (endpointName for Spring configuration) options MUST be provided.
Since 2.0, it is possible to use # notation to reference a serviceClass object instance from the registry..
Please be advised that the referenced object cannot be a Proxy (Spring AOP Proxy is OK) as it relies on Object.getClass().getName() method for non Spring AOP Proxy.
Since 2.8, it is possible to omit both wsdlURL and serviceClass options for PAYLOAD and MESSAGE mode. When they are omitted, arbitrary XML elements can be put in CxfPayload's body in PAYLOAD mode to facilitate CXF Dispatch Mode.
For example: org.apache.camel.Hello
serviceName Only if more than one serviceName present in WSDL
The service name this service is implementing, it maps to the wsdl:service@name. For example:
{http://org.apache.camel}ServiceName
portName Only if more than one portName under the serviceName is present, and it is required for camel-cxf consumer since camel 2.2
The port name this service is implementing, it maps to the wsdl:port@name. For example:
{http://org.apache.camel}PortName
dataFormat No Which message data format the CXF endpoint supports. Possible values are: POJO (default), PAYLOAD, MESSAGE.
relayHeaders No Please see the Description ofrelayHeadersoption section for this option. Should a CXF endpoint relay headers along the route. Currently only available when dataFormat=POJODefault: trueExample: true, false
wrapped No Which kind of operation the CXF endpoint producer will invoke. Possible values are: true, false (default).
wrappedStyle No Since 2.5.0 The WSDL style that describes how parameters are represented in the SOAP body. If the value is false, CXF will chose the document-literal unwrapped style, If the value is true, CXF will chose the document-literal wrapped style
setDefaultBus No Specifies whether or not to use the default CXF bus for this endpoint. Possible values are: true, false (default).
bus No
Use # notation to reference a bus object from the registry—for example, bus=#busName. The referenced object must be an instance of org.apache.cxf.Bus.
By default, uses the default bus created by CXF Bus Factory.
cxfBinding No
Use # notation to reference a CXF binding object from the registry—for example, cxfBinding=#bindingName. The referenced object must be an instance of org.apache.camel.component.cxf.CxfBinding.
headerFilterStrategy No Use # notation to reference a header filter strategy object from the registry—for example, headerFilterStrategy=#strategyName. The referenced object must be an instance of org.apache.camel.spi.HeaderFilterStrategy.
loggingFeatureEnabled No New in 2.3, this option enables CXF Logging Feature which writes inbound and outbound SOAP messages to log. Possible values are: true, false (default).
defaultOperationName No
New in 2.4, this option will set the default operationName that will be used by the CxfProducer that invokes the remote service. For example:
defaultOperationName=greetMe
defaultOperationNamespace No
New in 2.4, this option will set the default operationNamespace that will be used by the CxfProducer which invokes the remote service. For example:
defaultOperationNamespace= http://apache.org/hello_world_soap_http
synchronous No New in 2.5, this option will let CXF endpoint decide to use sync or async API to do the underlying work. The default value is false, which means camel-cxf endpoint will try to use async API by default.
publishedEndpointUrl No
New in 2.5, this option overrides the endpoint URL that appears in the published WSDL that is accessed using the service address URL plus ?wsdl. For example:
publshedEndpointUrl=http://example.com/service
properties.propName No Camel 2.8: Allows you to set custom CXF properties in the endpoint URI. For example, setting properties.mtom-enabled=true to enable MTOM.
allowStreaming No New in 2.8.2. This option controls whether the CXF component, when running in PAYLOAD mode (see below), will DOM parse the incoming messages into DOM Elements or keep the payload as a javax.xml.transform.Source object that would allow streaming in some cases.
skipFaultLogging No New in 2.11. This option controls whether the PhaseInterceptorChain skips logging the Fault that it catches.
The serviceName and portName are QNames, so if you provide them be sure to prefix them with their {namespace} as shown in the examples above.

The descriptions of the dataformats

DataFormat Description
POJO POJOs (plain old Java objects) are the Java parameters to the method being invoked on the target server. Both Protocol and Logical JAX-WS handlers are supported.
PAYLOAD PAYLOAD is the message payload (the contents of the soap:body) after message configuration in the CXF endpoint is applied. Only Protocol JAX-WS handler is supported. Logical JAX-WS handler is not supported.
MESSAGE MESSAGE is the raw message that is received from the transport layer. It is not suppose to touch or change Stream, some of the CXF interceptor will be removed if you are using this kind of DataFormat so you can't see any soap headers after the camel-cxf consumer and JAX-WS handler is not supported.
CXF_MESSAGE New in Camel 2.8.2, CXF_MESSAGE allows for invoking the full capabilities of CXF interceptors by converting the message from the transport layer into a raw SOAP message
You can determine the data format mode of an exchange by retrieving the exchange property, CamelCXFDataFormat. The exchange key constant is defined in org.apache.camel.component.cxf.CxfConstants.DATA_FORMAT_PROPERTY.

Configuring the CXF Endpoints with Apache Aries Blueprint.

Since Camel 2.8, there is support for using Aries blueprint dependency injection for your CXF endpoints. The schema is very similar to the Spring schema, so the transition is fairly transparent.
For example:
 <blueprint xmlns="http://www.osgi.org/xmlns/blueprint/v1.0.0"
            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
            xmlns:cm="http://aries.apache.org/blueprint/xmlns/blueprint-cm/v1.0.0"
            xmlns:camel-cxf="http://camel.apache.org/schema/blueprint/cxf"
 	   xmlns:cxfcore="http://cxf.apache.org/blueprint/core"
            xsi:schemaLocation="http://www.osgi.org/xmlns/blueprint/v1.0.0 http://www.osgi.org/xmlns/blueprint/v1.0.0/blueprint.xsd">
 
       <camel-cxf:cxfEndpoint id="routerEndpoint"
                      address="http://localhost:9001/router"
                      serviceClass="org.apache.servicemix.examples.cxf.HelloWorld">
         <camel-cxf:properties>
             <entry key="dataFormat" value="MESSAGE"/>
         </camel-cxf:properties>
      </camel-cxf:cxfEndpoint>
 
      <camel-cxf:cxfEndpoint id="serviceEndpoint"
			address="http://localhost:9000/SoapContext/SoapPort"
                     serviceClass="org.apache.servicemix.examples.cxf.HelloWorld">
    </camel-cxf:cxfEndpoint>

    <camelContext xmlns="http://camel.apache.org/schema/blueprint">
        <route>
            <from uri="routerEndpoint"/>
            <to uri="log:request"/>
        </route>
    </camelContext>

</blueprint>


Currently the endpoint element is the first supported CXF namespacehandler.
You can also use the bean references just as in spring
<blueprint xmlns="http://www.osgi.org/xmlns/blueprint/v1.0.0"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xmlns:cm="http://aries.apache.org/blueprint/xmlns/blueprint-cm/v1.0.0"
           xmlns:jaxws="http://cxf.apache.org/blueprint/jaxws"
           xmlns:cxf="http://cxf.apache.org/blueprint/core"
           xmlns:camel="http://camel.apache.org/schema/blueprint"
           xmlns:camelcxf="http://camel.apache.org/schema/blueprint/cxf"
           xsi:schemaLocation="
             http://www.osgi.org/xmlns/blueprint/v1.0.0 http://www.osgi.org/xmlns/blueprint/v1.0.0/blueprint.xsd
             http://cxf.apache.org/blueprint/jaxws http://cxf.apache.org/schemas/blueprint/jaxws.xsd
             http://cxf.apache.org/blueprint/core http://cxf.apache.org/schemas/blueprint/core.xsd
             ">

    <camelcxf:cxfEndpoint id="reportIncident"
                     address="/camel-example-cxf-blueprint/webservices/incident"
                     wsdlURL="META-INF/wsdl/report_incident.wsdl"
                     serviceClass="org.apache.camel.example.reportincident.ReportIncidentEndpoint">
    </camelcxf:cxfEndpoint>

    <bean id="reportIncidentRoutes" class="org.apache.camel.example.reportincident.ReportIncidentRoutes" />

    <camelContext xmlns="http://camel.apache.org/schema/blueprint">
        <routeBuilder ref="reportIncidentRoutes"/>
    </camelContext>

</blueprint>


How to enable CXF's LoggingOutInterceptor in MESSAGE mode

CXF's LoggingOutInterceptor outputs outbound message that goes on the wire to logging system (java.util.logging). Since the LoggingOutInterceptor is in PRE_STREAM phase (but PRE_STREAM phase is removed in MESSAGE mode), you have to configure LoggingOutInterceptor to be run during the WRITE phase. The following is an example.
   <bean id="loggingOutInterceptor" class="org.apache.cxf.interceptor.LoggingOutInterceptor">
        <!--  it really should have been user-prestream but CXF does have such phase! -->
        <constructor-arg value="target/write"/> 
   </bean>
   		
<cxf:cxfEndpoint id="serviceEndpoint" address="http://localhost:9002/helloworld"
	serviceClass="org.apache.camel.component.cxf.HelloService">
	<cxf:outInterceptors>
	    <ref bean="loggingOutInterceptor"/>
	</cxf:outInterceptors>
	<cxf:properties>
		<entry key="dataFormat" value="MESSAGE"/>
	</cxf:properties>
</cxf:cxfEndpoint>

Description of relayHeaders option

There are in-band and out-of-band on-the-wire headers from the perspective of a JAXWS WSDL-first developer.
The in-band headers are headers that are explicitly defined as part of the WSDL binding contract for an endpoint such as SOAP headers.
The out-of-band headers are headers that are serialized over the wire, but are not explicitly part of the WSDL binding contract.
Headers relaying/filtering is bi-directional.
When a route has a CXF endpoint and the developer needs to have on-the-wire headers, such as SOAP headers, be relayed along the route to be consumed say by another JAXWS endpoint, then relayHeaders should be set to true, which is the default value.

Available only in POJO mode

The relayHeaders=true setting expresses an intent to relay the headers. The actual decision on whether a given header is relayed is delegated to a pluggable instance that implements the MessageHeadersRelay interface. A concrete implementation of MessageHeadersRelay will be consulted to decide if a header needs to be relayed or not. There is already an implementation of SoapMessageHeadersRelay which binds itself to well-known SOAP name spaces. Currently only out-of-band headers are filtered, and in-band headers will always be relayed when relayHeaders=true. If there is a header on the wire, whose name space is unknown to the runtime, then a fall back DefaultMessageHeadersRelay will be used, which simply allows all headers to be relayed.
The relayHeaders=false setting asserts that all headers, in-band and out-of-band, will be dropped.
You can plugin your own MessageHeadersRelay implementations overriding or adding additional ones to the list of relays. In order to override a preloaded relay instance just make sure that your MessageHeadersRelay implementation services the same name spaces as the one you looking to override. Also note, that the overriding relay has to service all of the name spaces as the one you looking to override, or else a runtime exception on route start up will be thrown as this would introduce an ambiguity in name spaces to relay instance mappings.
<cxf:cxfEndpoint ...>
   <cxf:properties>
     <entry key="org.apache.camel.cxf.message.headers.relays">
       <list>
         <ref bean="customHeadersRelay"/>
       </list>
     </entry>
   </cxf:properties>
 </cxf:cxfEndpoint>
 <bean id="customHeadersRelay" class="org.apache.camel.component.cxf.soap.headers.CustomHeadersRelay"/>
Take a look at the tests that show how you'd be able to relay/drop headers here:

Changes since Release 2.0

  • POJO and PAYLOAD modes are supported. In POJO mode, only out-of-band message headers are available for filtering as the in-band headers have been processed and removed from the header list by CXF. The in-band headers are incorporated into the MessageContentList in POJO mode. The camel-cxf component does make any attempt to remove the in-band headers from the MessageContentList If filtering of in-band headers is required, please use PAYLOAD mode or plug in a (pretty straightforward) CXF interceptor/JAXWS Handler to the CXF endpoint.
  • The Message Header Relay mechanism has been merged into CxfHeaderFilterStrategy. The relayHeaders option, its semantics, and default value remain the same, but it is a property of CxfHeaderFilterStrategy. Here is an example of configuring it.
    <bean id="dropAllMessageHeadersStrategy" class="org.apache.camel.component.cxf.common.header.CxfHeaderFilterStrategy">
    
        <!--  Set relayHeaders to false to drop all SOAP headers -->
        <property name="relayHeaders" value="false"/>
        
    </bean>
    
    Then, your endpoint can reference the CxfHeaderFilterStrategy.
    <route>
        <from uri="cxf:bean:routerNoRelayEndpoint?headerFilterStrategy=#dropAllMessageHeadersStrategy"/>          
        <to uri="cxf:bean:serviceNoRelayEndpoint?headerFilterStrategy=#dropAllMessageHeadersStrategy"/>
    </route>
    
  • The MessageHeadersRelay interface has changed slightly and has been renamed to MessageHeaderFilter. It is a property of CxfHeaderFilterStrategy. Here is an example of configuring user defined Message Header Filters:
    <bean id="customMessageFilterStrategy" class="org.apache.camel.component.cxf.common.header.CxfHeaderFilterStrategy">
        <property name="messageHeaderFilters">
            <list>
                <!--  SoapMessageHeaderFilter is the built in filter.  It can be removed by omitting it. -->
                <bean class="org.apache.camel.component.cxf.common.header.SoapMessageHeaderFilter"/>
                
                <!--  Add custom filter here -->    
                <bean class="org.apache.camel.component.cxf.soap.headers.CustomHeaderFilter"/>
            </list>
        </property>
    </bean>
    
  • Other than relayHeaders, there are new properties that can be configured in CxfHeaderFilterStrategy.
Name Description type Required? Default value
relayHeaders All message headers will be processed by Message Header Filters boolean No true (1.6.1 behavior)
relayAllMessageHeaders All message headers will be propagated (without processing by Message Header Filters) boolean No false (1.6.1 behavior)
allowFilterNamespaceClash If two filters overlap in activation namespace, the property control how it should be handled. If the value is true, last one wins. If the value is false, it will throw an exception boolean No false (1.6.1 behavior)

Configure the CXF endpoints with Spring

You can configure the CXF endpoint with the Spring configuration file shown below, and you can also embed the endpoint into the camelContext tags. When you are invoking the service endpoint, you can set the operationName and operationNamespace headers to explicitly state which operation you are calling.
NOTE In Camel 2.x we change to use http://camel.apache.org/schema/cxf as the CXF endpoint's target namespace.
<beans xmlns="http://www.springframework.org/schema/beans"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xmlns:cxf="http://camel.apache.org/schema/cxf"
        xsi:schemaLocation="
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
        http://camel.apache.org/schema/cxf http://camel.apache.org/schema/cxf/camel-cxf.xsd
        http://camel.apache.org/schema/spring http://camel.apache.org/schema/spring/camel-spring.xsd     ">
 ...

Note

In Apache Camel 2.x, the http://activemq.apache.org/camel/schema/cxfEndpoint namespace was changed to http://camel.apache.org/schema/cxf.
Be sure to include the JAX-WS schemaLocation attribute specified on the root beans element. This allows CXF to validate the file and is required. Also note the namespace declarations at the end of the <cxf:cxfEndpoint/> tag--these are required because the combined {namespace}localName syntax is presently not supported for this tag's attribute values.
The cxf:cxfEndpoint element supports many additional attributes:
Name Value
PortName The endpoint name this service is implementing, it maps to the wsdl:port@name. In the format of ns:PORT_NAME where ns is a namespace prefix valid at this scope.
serviceName The service name this service is implementing, it maps to the wsdl:service@name. In the format of ns:SERVICE_NAME where ns is a namespace prefix valid at this scope.
wsdlURL The location of the WSDL. Can be on the classpath, file system, or be hosted remotely.
bindingId The bindingId for the service model to use.
address The service publish address.
bus The bus name that will be used in the JAX-WS endpoint.
serviceClass The class name of the SEI (Service Endpoint Interface) class which could have JSR181 annotation or not.
It also supports many child elements:
Name Value
cxf:inInterceptors The incoming interceptors for this endpoint. A list of <bean> or <ref>.
cxf:inFaultInterceptors The incoming fault interceptors for this endpoint. A list of <bean> or <ref>.
cxf:outInterceptors The outgoing interceptors for this endpoint. A list of <bean> or <ref>.
cxf:outFaultInterceptors The outgoing fault interceptors for this endpoint. A list of <bean> or <ref>.
cxf:properties A properties map which should be supplied to the JAX-WS endpoint. See below.
cxf:handlers A JAX-WS handler list which should be supplied to the JAX-WS endpoint. See below.
cxf:dataBinding You can specify the which DataBinding will be use in the endpoint. This can be supplied using the Spring <bean class="MyDataBinding"/> syntax.
cxf:binding You can specify the BindingFactory for this endpoint to use. This can be supplied using the Spring <bean class="MyBindingFactory"/> syntax.
cxf:features The features that hold the interceptors for this endpoint. A list of <bean>s or <ref>s
cxf:schemaLocations The schema locations for endpoint to use. A list of <schemaLocation>s
cxf:serviceFactory The service factory for this endpoint to use. This can be supplied using the Spring <bean class="MyServiceFactory"/> syntax
You can find more advanced examples which show how to provide interceptors, properties and handlers here: http://cwiki.apache.org/CXF20DOC/jax-ws-configuration.html

Note

You can use CXF:properties to set the CXF endpoint's dataFormat and setDefaultBus properties from a Spring configuration file, as follows:
<cxf:cxfEndpoint id="testEndpoint" address="http://localhost:9000/router"
     serviceClass="org.apache.camel.component.cxf.HelloService"
     endpointName="s:PortName"
     serviceName="s:ServiceName"
     xmlns:s="http://www.example.com/test">
     <cxf:properties>
       <entry key="dataFormat" value="MESSAGE"/>
       <entry key="setDefaultBus" value="true"/>
     </cxf:properties>
   </cxf:cxfEndpoint>

How to make the camel-cxf component use log4j instead of java.util.logging

CXF's default logger is java.util.logging. If you want to change it to log4j, proceed as follows. Create a file, in the classpath, named META-INF/cxf/org.apache.cxf.logger. This file should contain the fully-qualified name of the class, org.apache.cxf.common.logging.Log4jLogger, with no comments, on a single line.

How to let camel-cxf response message with xml start document

If you are using some soap client such as PHP, you will get this kind of error, because CXF doesn't add the XML start document "<?xml version="1.0" encoding="utf-8"?>"
Error:sendSms: SoapFault exception: [Client] looks like we got no XML document in [...]
To resolved this issue, you just need to tell StaxOutInterceptor to write the XML start document for you.
public class WriteXmlDeclarationInterceptor extends AbstractPhaseInterceptor<SoapMessage> {
    public WriteXmlDeclarationInterceptor() {
        super(Phase.PRE_STREAM);
        addBefore(StaxOutInterceptor.class.getName());
    }

    public void handleMessage(SoapMessage message) throws Fault {
        message.put("org.apache.cxf.stax.force-start-document", Boolean.TRUE);        
    }

}
You can add a customer interceptor like this and configure it into you camel-cxf endpont
<cxf:cxfEndpoint id="routerEndpoint" address="http://localhost:${CXFTestSupport.port2}/CXFGreeterRouterTest/CamelContext/RouterPort"
 		serviceClass="org.apache.hello_world_soap_http.GreeterImpl"
 		skipFaultLogging="true">
     <cxf:outInterceptors>
         <!-- This interceptor will force the CXF server send the XML start document to client -->
         <bean class="org.apache.camel.component.cxf.WriteXmlDeclarationInterceptor"/>
     </cxf:outInterceptors>
     <cxf:properties>
         <!-- Set the publishedEndpointUrl which could override the service address from generated WSDL as you want -->
         <entry key="publishedEndpointUrl" value="http://www.simple.com/services/test" />
     </cxf:properties>
 </cxf:cxfEndpoint>
Or adding a message header for it like this if you are using Camel 2.4.
 // set up the response context which force start document
 Map<String, Object> map = new HashMap<String, Object>();
 map.put("org.apache.cxf.stax.force-start-document", Boolean.TRUE);
 exchange.getOut().setHeader(Client.RESPONSE_CONTEXT, map);

How to consume a message from a camel-cxf endpoint in POJO data format

The camel-cxf endpoint consumer POJO data format is based on the cxf invoker, so the message header has a property with the name of CxfConstants.OPERATION_NAME and the message body is a list of the SEI method parameters.
public class PersonProcessor implements Processor {

    private static final transient Logger LOG = LoggerFactory.getLogger(PersonProcessor.class);

    @SuppressWarnings("unchecked")
    public void process(Exchange exchange) throws Exception {
        LOG.info("processing exchange in camel");

        BindingOperationInfo boi = (BindingOperationInfo)exchange.getProperty(BindingOperationInfo.class.toString());
        if (boi != null) {
            LOG.info("boi.isUnwrapped" + boi.isUnwrapped());
        }
        // Get the parameters list which element is the holder.
        MessageContentsList msgList = (MessageContentsList)exchange.getIn().getBody();
        Holder<String> personId = (Holder<String>)msgList.get(0);
        Holder<String> ssn = (Holder<String>)msgList.get(1);
        Holder<String> name = (Holder<String>)msgList.get(2);

        if (personId.value == null || personId.value.length() == 0) {
            LOG.info("person id 123, so throwing exception");
            // Try to throw out the soap fault message
            org.apache.camel.wsdl_first.types.UnknownPersonFault personFault =
                new org.apache.camel.wsdl_first.types.UnknownPersonFault();
            personFault.setPersonId("");
            org.apache.camel.wsdl_first.UnknownPersonFault fault =
                new org.apache.camel.wsdl_first.UnknownPersonFault("Get the null value of person name", personFault);
            // Since camel has its own exception handler framework, we can't throw the exception to trigger it
            // We just set the fault message in the exchange for camel-cxf component handling and return
            exchange.getOut().setFault(true);
            exchange.getOut().setBody(fault);
            return;
        }

        name.value = "Bonjour";
        ssn.value = "123";
        LOG.info("setting Bonjour as the response");
        // Set the response message, first element is the return value of the operation,
        // the others are the holders of method parameters
        exchange.getOut().setBody(new Object[] {null, personId, ssn, name});
    }

}

How to prepare the message for the camel-cxf endpoint in POJO data format

The camel-cxf endpoint producer is based on the cxf client API. First you need to specify the operation name in the message header, then add the method parameters to a list, and initialize the message with this parameter list. The response message's body is a messageContentsList, you can get the result from that list.
If you want to get the object array from the message body, you can get the body using message.getbody(Object[].class), as follows:
Exchange senderExchange = new DefaultExchange(context, ExchangePattern.InOut);
final List<String> params = new ArrayList<String>();
// Prepare the request message for the camel-cxf procedure
params.add(TEST_MESSAGE);
senderExchange.getIn().setBody(params);
senderExchange.getIn().setHeader(CxfConstants.OPERATION_NAME, ECHO_OPERATION);

Exchange exchange = template.send("direct:EndpointA", senderExchange);

org.apache.camel.Message out = exchange.getOut();
// The response message's body is an MessageContentsList which first element is the return value of the operation,
// If there are some holder parameters, the holder parameter will be filled in the reset of List.
// The result will be extract from the MessageContentsList with the String class type
MessageContentsList result = (MessageContentsList)out.getBody();
LOG.info("Received output text: " + result.get(0));
Map<String, Object> responseContext = CastUtils.cast((Map<?, ?>)out.getHeader(Client.RESPONSE_CONTEXT));
assertNotNull(responseContext);
assertEquals("We should get the response context here", "UTF-8", responseContext.get(org.apache.cxf.message.Message.ENCODING));
assertEquals("Reply body on Camel is wrong", "echo " + TEST_MESSAGE, result.get(0));

How to deal with the message for a camel-cxf endpoint in PAYLOAD data format

In Apache Camel 2.0: CxfMessage.getBody() will return an org.apache.camel.component.cxf.CxfPayload object, which has getters for SOAP message headers and Body elements. This change enables decoupling the native CXF message from the Apache Camel message.
protected RouteBuilder createRouteBuilder() {
    return new RouteBuilder() {
        public void configure() {
            from(SIMPLE_ENDPOINT_URI + "&dataFormat=PAYLOAD").to("log:info").process(new Processor() {
                @SuppressWarnings("unchecked")
                public void process(final Exchange exchange) throws Exception {                        
                    CxfPayload<SoapHeader> requestPayload = exchange.getIn().getBody(CxfPayload.class);
                    List<Source> inElements = requestPayload.getBodySources();
                    List<Source> outElements = new ArrayList<Source>();
                    // You can use a customer toStringConverter to turn a CxfPayLoad message into String as you want                        
                    String request = exchange.getIn().getBody(String.class);
                    XmlConverter converter = new XmlConverter();
                    String documentString = ECHO_RESPONSE;
                    
                    Element in = new XmlConverter().toDOMElement(inElements.get(0));
                    // Just check the element namespace
                    if (!in.getNamespaceURI().equals(ELEMENT_NAMESPACE)) {
                        throw new IllegalArgumentException("Wrong element namespace");
                    }
                    if (in.getLocalName().equals("echoBoolean")) {
                        documentString = ECHO_BOOLEAN_RESPONSE;
                        checkRequest("ECHO_BOOLEAN_REQUEST", request);
                    } else {
                        documentString = ECHO_RESPONSE;
                        checkRequest("ECHO_REQUEST", request);
                    }
                    Document outDocument = converter.toDOMDocument(documentString);
                    outElements.add(new DOMSource(outDocument.getDocumentElement()));
                    // set the payload header with null
                    CxfPayload<SoapHeader> responsePayload = new CxfPayload<SoapHeader>(null, outElements, null);
                    exchange.getOut().setBody(responsePayload); 
                }
            });
        }
    };
}

How to get and set SOAP headers in POJO mode

POJO means that the data format is a list of Java objects when the CXF endpoint produces or consumes Camel exchanges. Even though Apache Camel exposes the message body as POJOs in this mode, the CXF component still provides access to read and write SOAP headers. However, since CXF interceptors remove in-band SOAP headers from the header list after they have been processed, only out-of-band SOAP headers are available in POJO mode.
The following example illustrates how to get/set SOAP headers. Suppose we have a route that forwards from one CXF endpoint to another. That is, SOAP Client -> Apache Camel -> CXF service. We can attach two processors to obtain/insert SOAP headers at (1) before request goes out to the CXF service and (2) before response comes back to the SOAP Client. Processor (1) and (2) in this example are InsertRequestOutHeaderProcessor and InsertResponseOutHeaderProcessor. Our route looks like this:
<route>
    <from uri="cxf:bean:routerRelayEndpointWithInsertion"/>
    <process ref="InsertRequestOutHeaderProcessor" />
    <to uri="cxf:bean:serviceRelayEndpointWithInsertion"/>
    <process ref="InsertResponseOutHeaderProcessor" />
</route>
In 2.x SOAP headers are propagated to and from Apache Camel Message headers. The Apache Camel message header name is org.apache.cxf.headers.Header.list, which is a constant defined in CXF (org.apache.cxf.headers.Header.HEADER_LIST). The header value is a List<> of CXF SoapHeader objects (org.apache.cxf.binding.soap.SoapHeader). The following snippet is the InsertResponseOutHeaderProcessor (that inserts a new SOAP header in the response message). The way to access SOAP headers in both InsertResponseOutHeaderProcessor and InsertRequestOutHeaderProcessor are actually the same. The only difference between the two processors is setting the direction of the inserted SOAP header.
public static class InsertResponseOutHeaderProcessor implements Processor {

    @SuppressWarnings("unchecked")
    public void process(Exchange exchange) throws Exception {
        // You should be able to get the header if exchange is routed from camel-cxf endpoint
        List<SoapHeader> soapHeaders = CastUtils.cast((List<?>)exchange.getIn().getHeader(Header.HEADER_LIST));
        if (soapHeaders == null) {
            // we just create a new soap headers in case the header is null
            soapHeaders = new ArrayList<SoapHeader>();
        }

        // Insert a new header
        String xml = "<?xml version=\"1.0\" encoding=\"utf-8\"?><outofbandHeader "
            + "xmlns=\"http://cxf.apache.org/outofband/Header\" hdrAttribute=\"testHdrAttribute\" "
            + "xmlns:soap=\"http://schemas.xmlsoap.org/soap/envelope/\" soap:mustUnderstand=\"1\">"
            + "<name>New_testOobHeader</name><value>New_testOobHeaderValue</value></outofbandHeader>";
        SoapHeader newHeader = new SoapHeader(soapHeaders.get(0).getName(),
                       DOMUtils.readXml(new StringReader(xml)).getDocumentElement());
        // make sure direction is OUT since it is a response message.
        newHeader.setDirection(Direction.DIRECTION_OUT);
        //newHeader.setMustUnderstand(false);
        soapHeaders.add(newHeader);
        
    }
    
}

How to get and set SOAP headers in PAYLOAD mode

We have already shown how to access SOAP message (CxfPayload object) in PAYLOAD mode (see the section called “How to deal with the message for a camel-cxf endpoint in PAYLOAD data format”).
Once you obtain a CxfPayload object, you can invoke the CxfPayload.getHeaders() method that returns a List of DOM Elements (SOAP headers).
from(getRouterEndpointURI()).process(new Processor() {
    @SuppressWarnings("unchecked")
    public void process(Exchange exchange) throws Exception {
        CxfPayload<SoapHeader> payload = exchange.getIn().getBody(CxfPayload.class);
        List<Source> elements = payload.getBodySources();
        assertNotNull("We should get the elements here", elements);
        assertEquals("Get the wrong elements size", 1, elements.size());
                
        Element el = new XmlConverter().toDOMElement(elements.get(0));
        elements.set(0, new DOMSource(el));
        assertEquals("Get the wrong namespace URI", "http://camel.apache.org/pizza/types", 
                el.getNamespaceURI());
            
        List<SoapHeader> headers = payload.getHeaders();
        assertNotNull("We should get the headers here", headers);
        assertEquals("Get the wrong headers size", headers.size(), 1);
        assertEquals("Get the wrong namespace URI", 
                ((Element)(headers.get(0).getObject())).getNamespaceURI(), 
                "http://camel.apache.org/pizza/types");         
    }
    
})
.to(getServiceEndpointURI());

SOAP headers are not available in MESSAGE mode

SOAP headers are not available in MESSAGE mode as SOAP processing is skipped.

How to throw a SOAP Fault from Apache Camel

If you are using a CXF endpoint to consume the SOAP request, you may need to throw the SOAP Fault from the camel context. Basically, you can use the throwFault DSL to do that; it works for POJO, PAYLOAD and MESSAGE data format. You can define the soap fault like this:
SOAP_FAULT = new SoapFault(EXCEPTION_MESSAGE, SoapFault.FAULT_CODE_CLIENT);
Element detail = SOAP_FAULT.getOrCreateDetail();
Document doc = detail.getOwnerDocument();
Text tn = doc.createTextNode(DETAIL_TEXT);
detail.appendChild(tn);
Then throw it as you like:
from(routerEndpointURI).setFaultBody(constant(SOAP_FAULT));
If your CXF endpoint is working in the MESSAGE data format, you could set the the SOAP Fault message in the message body and set the response code in the message header.
from(routerEndpointURI).process(new Processor() {

    public void process(Exchange exchange) throws Exception {
        Message out = exchange.getOut();
        // Set the message body with the 
        out.setBody(this.getClass().getResourceAsStream("SoapFaultMessage.xml"));
        // Set the response code here
        out.setHeader(org.apache.cxf.message.Message.RESPONSE_CODE, new Integer(500));
    }

});
The same is true for the POJO data format. You can set the SOAP Fault on the Out body and also indicate it's a fault by calling Message.setFault(true), as follows:
from("direct:start").onException(SoapFault.class).maximumRedeliveries(0).handled(true)
    .process(new Processor() {
        public void process(Exchange exchange) throws Exception {
            SoapFault fault = exchange
                .getProperty(Exchange.EXCEPTION_CAUGHT, SoapFault.class);
            exchange.getOut().setFault(true);
            exchange.getOut().setBody(fault);
        }

    }).end().to(serviceURI);

How to propagate a CXF endpoint's request and response context

cxf client API provides a way to invoke the operation with request and response context. If you are using a CXF endpoint producer to invoke the external Web service, you can set the request context and get the response context with the following code:
        CxfExchange exchange = (CxfExchange)template.send(getJaxwsEndpointUri(), new Processor() {
             public void process(final Exchange exchange) {
                 final List<String> params = new ArrayList<String>();
                 params.add(TEST_MESSAGE);
                 // Set the request context to the inMessage
                 Map<String, Object> requestContext = new HashMap<String, Object>();
                 requestContext.put(BindingProvider.ENDPOINT_ADDRESS_PROPERTY, JAXWS_SERVER_ADDRESS);
                 exchange.getIn().setBody(params);
                 exchange.getIn().setHeader(Client.REQUEST_CONTEXT , requestContext);
                 exchange.getIn().setHeader(CxfConstants.OPERATION_NAME, GREET_ME_OPERATION);
             }
         });
         org.apache.camel.Message out = exchange.getOut();
         // The output is an object array, the first element of the array is the return value
         Object\[\] output = out.getBody(Object\[\].class);
         LOG.info("Received output text: " + output\[0\]);
         // Get the response context form outMessage
         Map<String, Object> responseContext = CastUtils.cast((Map)out.getHeader(Client.RESPONSE_CONTEXT));
         assertNotNull(responseContext);
         assertEquals("Get the wrong wsdl opertion name", "{http://apache.org/hello_world_soap_http}greetMe",
                      responseContext.get("javax.xml.ws.wsdl.operation").toString());

Attachment Support

POJO Mode: Both SOAP with Attachment and MTOM are supported (see example in Payload Mode for enabling MTOM). However, SOAP with Attachment is not tested. Since attachments are marshalled and unmarshalled into POJOs, users typically do not need to deal with the attachment themself. Attachments are propagated to Camel message's attachments since 2.1. So, it is possible to retreive attachments by Camel Message API
DataHandler Message.getAttachment(String id)
.
Payload Mode: MTOM is supported since 2.1. Attachments can be retrieved by Camel Message APIs mentioned above. SOAP with Attachment is not supported as there is no SOAP processing in this mode.
To enable MTOM, set the CXF endpoint property "mtom_enabled" to true. (I believe you can only do it with Spring.)
<cxf:cxfEndpoint id="routerEndpoint" address="http://localhost:${CXFTestSupport.port1}/CxfMtomRouterPayloadModeTest/jaxws-mtom/hello"
         wsdlURL="mtom.wsdl"
         serviceName="ns:HelloService"
         endpointName="ns:HelloPort"
         xmlns:ns="http://apache.org/camel/cxf/mtom_feature">

     <cxf:properties>
         <!--  enable mtom by setting this property to true -->
         <entry key="mtom-enabled" value="true"/>
         
         <!--  set the camel-cxf endpoint data fromat to PAYLOAD mode -->
         <entry key="dataFormat" value="PAYLOAD"/>
     </cxf:properties>
You can produce a Camel message with attachment to send to a CXF endpoint in Payload mode.
Exchange exchange = context.createProducerTemplate().send("direct:testEndpoint", new Processor() {

    public void process(Exchange exchange) throws Exception {
        exchange.setPattern(ExchangePattern.InOut);
        List&lt;Source> elements = new ArrayList&lt;Source>();
        elements.add(new DOMSource(DOMUtils.readXml(new StringReader(MtomTestHelper.REQ_MESSAGE)).getDocumentElement()));
        CxfPayload<SoapHeader> body = new CxfPayload<SoapHeader>(new ArrayList<SoapHeader>(),
            elements, null);
        exchange.getIn().setBody(body);
        exchange.getIn().addAttachment(MtomTestHelper.REQ_PHOTO_CID, 
            new DataHandler(new ByteArrayDataSource(MtomTestHelper.REQ_PHOTO_DATA, "application/octet-stream")));

        exchange.getIn().addAttachment(MtomTestHelper.REQ_IMAGE_CID, 
            new DataHandler(new ByteArrayDataSource(MtomTestHelper.requestJpeg, "image/jpeg")));

    }
    
});

// process response 

CxfPayload<SoapHeader> out = exchange.getOut().getBody(CxfPayload.class);
Assert.assertEquals(1, out.getBody().size());

Map<String, String> ns = new HashMap<String, String>();
ns.put("ns", MtomTestHelper.SERVICE_TYPES_NS);
ns.put("xop", MtomTestHelper.XOP_NS);

XPathUtils xu = new XPathUtils(ns);
Element oute = new XmlConverter().toDOMElement(out.getBody().get(0));
Element ele = (Element)xu.getValue("//ns:DetailResponse/ns:photo/xop:Include", oute,
                                   XPathConstants.NODE);
String photoId = ele.getAttribute("href").substring(4); // skip "cid:"

ele = (Element)xu.getValue("//ns:DetailResponse/ns:image/xop:Include", oute,
                                   XPathConstants.NODE);
String imageId = ele.getAttribute("href").substring(4); // skip "cid:"

DataHandler dr = exchange.getOut().getAttachment(photoId);
Assert.assertEquals("application/octet-stream", dr.getContentType());
MtomTestHelper.assertEquals(MtomTestHelper.RESP_PHOTO_DATA, IOUtils.readBytesFromStream(dr.getInputStream()));
   
dr = exchange.getOut().getAttachment(imageId);
Assert.assertEquals("image/jpeg", dr.getContentType());

BufferedImage image = ImageIO.read(dr.getInputStream());
Assert.assertEquals(560, image.getWidth());
Assert.assertEquals(300, image.getHeight());
You can also consume a Camel message received from a CXF endpoint in Payload mode.
public static class MyProcessor implements Processor {

    @SuppressWarnings("unchecked")
    public void process(Exchange exchange) throws Exception {
        CxfPayload<SoapHeader> in = exchange.getIn().getBody(CxfPayload.class);
        
        // verify request
        assertEquals(1, in.getBody().size());
        
        Map<String, String> ns = new HashMap<String, String>();
        ns.put("ns", MtomTestHelper.SERVICE_TYPES_NS);
        ns.put("xop", MtomTestHelper.XOP_NS);

        XPathUtils xu = new XPathUtils(ns);
        Element body = new XmlConverter().toDOMElement(in.getBody().get(0));
        Element ele = (Element)xu.getValue("//ns:Detail/ns:photo/xop:Include", body,
                                           XPathConstants.NODE);
        String photoId = ele.getAttribute("href").substring(4); // skip "cid:"
        assertEquals(MtomTestHelper.REQ_PHOTO_CID, photoId);
        
        ele = (Element)xu.getValue("//ns:Detail/ns:image/xop:Include", body,
                                           XPathConstants.NODE);
        String imageId = ele.getAttribute("href").substring(4); // skip "cid:"
        assertEquals(MtomTestHelper.REQ_IMAGE_CID, imageId);

        DataHandler dr = exchange.getIn().getAttachment(photoId);
        assertEquals("application/octet-stream", dr.getContentType());
        MtomTestHelper.assertEquals(MtomTestHelper.REQ_PHOTO_DATA, IOUtils.readBytesFromStream(dr.getInputStream()));
   
        dr = exchange.getIn().getAttachment(imageId);
        assertEquals("image/jpeg", dr.getContentType());
        MtomTestHelper.assertEquals(MtomTestHelper.requestJpeg, IOUtils.readBytesFromStream(dr.getInputStream()));

        // create response
        List&lt;Source> elements = new ArrayList&lt;Source>();
        elements.add(new DOMSource(DOMUtils.readXml(new StringReader(MtomTestHelper.RESP_MESSAGE)).getDocumentElement()));
        CxfPayload&lt;SoapHeader> sbody = new CxfPayload&lt;SoapHeader>(new ArrayList&lt;SoapHeader>(),
            elements, null);
        exchange.getOut().setBody(sbody);
        exchange.getOut().addAttachment(MtomTestHelper.RESP_PHOTO_CID, 
            new DataHandler(new ByteArrayDataSource(MtomTestHelper.RESP_PHOTO_DATA, "application/octet-stream")));

        exchange.getOut().addAttachment(MtomTestHelper.RESP_IMAGE_CID, 
            new DataHandler(new ByteArrayDataSource(MtomTestHelper.responseJpeg, "image/jpeg")));

    }
}
Message Mode: Attachments are not supported as it does not process the message at all.

How to propagate stack trace information

It is possible to configure a CXF endpoint so that, when a Java exception is thrown on the server side, the stack trace for the exception is marshalled into a fault message and returned to the client. To enable this feaure, set the dataFormat to PAYLOAD and set the faultStackTraceEnabled property to true in the cxfEndpoint element, as follows:
<cxf:cxfEndpoint id="router" address="http://localhost:9002/TestMessage"
    wsdlURL="ship.wsdl"
    endpointName="s:TestSoapEndpoint"
    serviceName="s:TestService"
    xmlns:s="http://test">
  <cxf:properties>
    <!-- enable sending the stack trace back to client; the default value is false-->
    <entry key="faultStackTraceEnabled" value="true" />
    <entry key="dataFormat" value="PAYLOAD" />
  </cxf:properties>
</cxf:cxfEndpoint>
For security reasons, the stack trace does not include the causing exception (that is, the part of a stack trace that follows Caused by). If you want to include the causing exception in the stack trace, set the exceptionMessageCauseEnabled property to true in the cxfEndpoint element, as follows:
<cxf:cxfEndpoint id="router" address="http://localhost:9002/TestMessage"
    wsdlURL="ship.wsdl"
    endpointName="s:TestSoapEndpoint"
    serviceName="s:TestService"
    xmlns:s="http://test">
  <cxf:properties>
    <!-- enable to show the cause exception message and the default value is false -->
 <entry key="exceptionMessageCauseEnabled" value="true" />
    <!-- enable to send the stack trace back to client,  the default value is false-->
    <entry key="faultStackTraceEnabled" value="true" />
    <entry key="dataFormat" value="PAYLOAD" />
  </cxf:properties>
</cxf:cxfEndpoint>

Warning

You should only enable the exceptionMessageCauseEnabled flag for testing and diagnostic purposes. It is normal practice for servers to conceal the original cause of an exception to make it harder for hostile users to probe the server.

Streaming Support in PAYLOAD mode

In 2.8.2, the camel-cxf component now supports streaming of incoming messages when using PAYLOAD mode. Previously, the incoming messages would have been completely DOM parsed. For large messages, this is time consuming and uses a significant amount of memory. Starting in 2.8.2, the incoming messages can remain as a javax.xml.transform.Source while being routed and, if nothing modifies the payload, can then be directly streamed out to the target destination. For common "simple proxy" use cases (example: from("cxf:...").to("cxf:...")), this can provide very significant performance increases as well as significantly lowered memory requirements.
However, there are cases where streaming may not be appropriate or desired. Due to the streaming nature, invalid incoming XML may not be caught until later in the processing chain. Also, certain actions may require the message to be DOM parsed anyway (like WS-Security or message tracing and such) in which case the advantages of the streaming is limited. At this point, there are two ways to control the streaming:
  • Endpoint property: you can add "allowStreaming=false" as an endpoint property to turn the streaming on/off.
  • Component property: the CxfComponent object also has an allowStreaming property that can set the default for endpoints created from that component.
  • Global system property: you can add a system property of "org.apache.camel.component.cxf.streaming" to "false" to turn if off. That sets the global default, but setting the endpoint property above will override this value for that endpoint.

Chapter 22. CXF Bean Component

CXF Bean Component (2.0 or later)

The cxfbean: component allows other Camel endpoints to send exchange and invoke Web service bean objects. (Currently, it only supports JAXRS, JAXWS(new to camel2.1) annotated service bean.)

Important

CxfBeanEndpoint is a ProcessorEndpoint so it has no consumers. It works similarly to a Bean component.

URI format

cxfbean:serviceBeanRef
Where serviceBeanRef is a registry key to look up the service bean object. If serviceBeanRef references a List object, elements of the List are the service bean objects accepted by the endpoint.

Options

Name Description Example Required? Default Value
bus CXF bus reference specified by the \# notation. The referenced object must be an instance of org.apache.cxf.Bus. bus=#busName No Default bus created by CXF Bus Factory
cxfBeanBinding CXF bean binding specified by the \# notation. The referenced object must be an instance of org.apache.camel.component.cxf.cxfbean.CxfBeanBinding. cxfBinding=#bindingName No DefaultCxfBeanBinding
headerFilterStrategy Header filter strategy specified by the \# notation. The referenced object must be an instance of org.apache.camel.spi.HeaderFilterStrategy. headerFilterStrategy=#strategyName No CxfHeaderFilterStrategy
populateFromClass Since 2.3, the wsdlLocation annotated in the POJO is ignored (by default) unless this option is set to false. Prior to 2.3, the wsdlLocation annotated in the POJO is always honored and it is not possible to ignore. true, false No true
providers Since 2.5, setting the providers for the CXFRS endpoint. providers=#providerRef1,#providerRef2 No null
setDefaultBus Will set the default bus when CXF endpoint create a bus by itself. true, false No false

Headers

Name Description Type Required? Default Value In/Out Examples
CamelHttpCharacterEncoding (before 2.0-m2: CamelCxfBeanCharacterEncoding) Character encoding String No None In ISO-8859-1
CamelContentType (before 2.0-m2: CamelCxfBeanContentType) Content type String No \**/*\* In text/xml
CamelHttpBaseUri (2.0-m3 and before: CamelCxfBeanRequestBasePath)
The value of this header will be set in the CXF message as the Message.BASE_PATH property. It is needed by CXF JAX-RS processing. Basically, it is the scheme, host and port portion of the request URI. String Yes The Endpoint URI of the source endpoint in the Camel exchange In http://localhost:9000
CamelHttpPath (before 2.0-m2: CamelCxfBeanRequestPat{}h) Request URI's path String Yes None In consumer/123
CamelHttpMethod (before 2.0-m2: CamelCxfBeanVerb) RESTful request verb String Yes None In GET, PUT, POST, DELETE
CamelHttpResponseCode HTTP response code Integer No None Out 200

Note

Currently, CXF Bean component has (only) been tested with Jetty HTTP component it can understand headers from Jetty HTTP component without requiring conversion.

A Working Sample

This sample shows how to create a route that starts a Jetty HTTP server. The route sends requests to a CXF Bean and invokes a JAXRS annotated service.
First, create a route as follows. The from endpoint is a Jetty HTTP endpoint that is listening on port 9000. Notice that the matchOnUriPrefix option must be set to true because RESTful request URI will not match the endpoint's URI http://localhost:9000 exactly.
<route>
	<from uri="jetty:http://localhost:9000?matchOnUriPrefix=true" />
	<to uri="cxfbean:customerServiceBean" />
	<to uri="mock:endpointA" />
</route>
The to endpoint is a CXF Bean with bean name customerServiceBean. The name will be looked up from the registry. Next, we make sure our service bean is available in Spring registry. We create a bean definition in the Spring configuration. In this example, we create a List of service beans (of one element). We could have created just a single bean without a List.
<util:list id="customerServiceBean">
	<bean class="org.apache.camel.component.cxf.jaxrs.testbean.CustomerService" />
</util:list>

<bean class="org.apache.camel.wsdl_first.PersonImpl" id="jaxwsBean" />
That's it. Once the route is started, the web service is ready for business. A HTTP client can make a request and receive response.
url = new URL("http://localhost:9000/customerservice/orders/223/products/323");
in = url.openStream();
assertEquals("{\"Product\":{\"description\":\"product 323\",\"id\":323}}", CxfUtils.getStringFromInputStream(in));

Chapter 23. CXFRS

CXFRS Component

The cxfrs: component provides integration with Apache CXF for connecting to JAX-RS services hosted in CXF.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
   <groupId>org.apache.camel</groupId>
   <artifactId>camel-cxf</artifactId>
   <version>x.x.x</version>  <!-- use the same version as your Camel core version -->
</dependency>

Note

When using CXF as a consumer, the CAMEL:CXF Bean Component allows you to factor out how message payloads are received from their processing as a RESTful or SOAP web service. This has the potential of using a multitude of transports to consume web services. The bean component's configuration is also simpler and provides the fastest method to implement web services using Camel and CXF.

URI format

cxfrs://address?options
Where address represents the CXF endpoint's address
cxfrs:bean:rsEndpoint
Where rsEndpoint represents the Spring bean's name which represents the CXFRS client or server
For either style above, you can append options to the URI as follows:
cxfrs:bean:cxfEndpoint?resourceClasses=org.apache.camel.rs.Example

Options

Name Description Example Required? default value
resourceClasses The resource classes which you want to export as REST service. Multiple classes can be separated by a comma.
resourceClasses=org.apache.camel.rs.Example1,org.apache.camel.rs.Exchange2
No None
httpClientAPI New to Apache Camel 2.1 If true, the CxfRsProducer will use the HttpClientAPI to invoke the service httpClientAPI=true No true
synchronous New in 2.5, this option will let CxfRsConsumer decide to use sync or async API to do the underlying work. The default value is false which means it will try to use async API by default. synchronous=true No false
throwExceptionOnFailure New in 2.6, this option tells the CxfRsProducer to inspect return codes and will generate an Exception if the return code is larger than 207. throwExceptionOnFailure=true No true
maxClientCacheSize New in 2.6, you can set the In message header, CamelDestinationOverrideUrl, to dynamically override the target destination Web Service or REST Service defined in your routes. The implementation caches CXF clients or ClientFactoryBean in CxfProvider and CxfRsProvider. This option allows you to configure the maximum size of the cache. maxClientCacheSize=5 No 10
setDefaultBus New in 2.9.0. Will set the default bus when CXF endpoint create a bus by itself setDefaultBus=true No false
bus New in 2.9.0. A default bus created by CXF Bus Factory. Use \# notation to reference a bus object from the registry. The referenced object must be an instance of org.apache.cxf.Bus. bus=#busName No None
bindingStyle
As of 2.11. Sets how requests and responses will be mapped to/from Camel. Two values are possible:
bindingStyle=SimpleConsumer No Default
You can also configure the CXF REST endpoint through the Spring configuration. Since there are lots of differences between the CXF REST client and CXF REST Server, we provide different configurations for them. Please check out the schema file and CXF REST user guide for more information.

How to configure the REST endpoint in Apache Camel

In camel-cxf schema file, there are two elements for the REST endpoint definition. cxf:rsServer for REST consumer, cxf:rsClient for REST producer. You can find a Apache Camel REST service route configuration example here.
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:cxf="http://camel.apache.org/schema/cxf"
       xmlns:jaxrs="http://cxf.apache.org/jaxrs"
       xsi:schemaLocation="
       http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
       http://camel.apache.org/schema/cxf http://camel.apache.org/schema/cxf/camel-cxf.xsd
       http://cxf.apache.org/jaxrs http://cxf.apache.org/schemas/jaxrs.xsd
       http://camel.apache.org/schema/spring http://camel.apache.org/schema/spring/camel-spring.xsd
    ">
  <!-- Defined the real JAXRS back end service  -->
  <jaxrs:server id="restService"
		        address="http://localhost:9002/rest" 
		        staticSubresourceResolution="true">
    <jaxrs:serviceBeans>
      <ref bean="customerService"/>
    </jaxrs:serviceBeans>       
  </jaxrs:server>
  
  <!--bean id="jsonProvider" class="org.apache.cxf.jaxrs.provider.JSONProvider"/-->

  <bean id="customerService" class="org.apache.camel.component.cxf.jaxrs.testbean.CustomerService" />
   
  <!-- Defined the server endpoint to create the cxf-rs consumer --> 
  <cxf:rsServer id="rsServer" address="http://localhost:9000/route"
    serviceClass="org.apache.camel.component.cxf.jaxrs.testbean.CustomerService" 
      loggingFeatureEnabled="true" loggingSizeLimit="20" skipFaultLogging="true"/>

  <!-- Defined the client endpoint to create the cxf-rs consumer -->
  <cxf:rsClient id="rsClient" address="http://localhost:9002/rest"
    serviceClass="org.apache.camel.component.cxf.jaxrs.testbean.CustomerService"
      loggingFeatureEnabled="true" skipFaultLogging="true"/>
  
  <!-- The camel route context -->
  <camelContext id="camel" xmlns="http://camel.apache.org/schema/spring">
    <route>
       <from uri="cxfrs://bean://rsServer"/>
       <!-- We can remove this configure as the CXFRS producer is using the HttpAPI by default -->
       <setHeader headerName="CamelCxfRsUsingHttpAPI">
         <constant>True</constant>        
       </setHeader>
       <to uri="cxfrs://bean://rsClient"/>
    </route>
  </camelContext>
  
</beans>

Consuming a REST Request - Simple Binding Style

Available as of Camel 2.11
The Default binding style is rather low-level, requiring the user to manually process the MessageContentsList object coming into the route. Thus, it tightly couples the route logic with the method signature and parameter indices of the JAX-RS operation. Somewhat inelegant, difficult and error-prone.
In contrast, the SimpleConsumer binding style performs the following mappings, in order to make the request data more accessible to you within the Camel Message:
  • JAX-RS Parameters (@HeaderParam, @QueryParam, etc.) are injected as IN message headers. The header name matches the value of the annotation.
  • The request entity (POJO or other type) becomes the IN message body. If a single entity cannot be identified in the JAX-RS method signature, it falls back to the original MessageContentsList.
  • Binary @Multipart body parts become IN message attachments, supporting DataHandler, InputStream, DataSource and CXF's Attachment class.
  • Non-binary @Multipart body parts are mapped as IN message headers. The header name matches the Body Part name.
Additionally, the following rules apply to the Response mapping:
  • If the message body type is different to javax.ws.rs.core.Response (user-built response), a new Response is created and the message body is set as the entity (so long it's not null). The response status code is taken from the Exchange.HTTP_RESPONSE_CODE header, or defaults to 200 OK if not present.
  • If the message body type is equal to javax.ws.rs.core.Response, it means that the user has built a custom response, and therefore it is respected and it becomes the final response.
  • In all cases, Camel headers permitted by custom or default HeaderFilterStrategy are added to the HTTP response.

Enabling the Simple Binding Style

This binding style can be activated by setting the bindingStyle parameter in the consumer endpoint to value SimpleConsumer:
  from("cxfrs:bean:rsServer?bindingStyle=SimpleConsumer")
    .to("log:TEST?showAll=true");

Examples of request binding with different method signatures

Below is a list of method signatures along with the expected result from the Simple binding.
public Response doAction(BusinessObject request); Request payload is placed in IN message body, replacing the original MessageContentsList.
public Response doAction(BusinessObject request, @HeaderParam("abcd") String abcd, @QueryParam("defg") String defg); Request payload placed in IN message body, replacing the original MessageContentsList. Both request params mapped as IN message headers with names abcd and defg.
public Response doAction(@HeaderParam("abcd") String abcd, @QueryParam("defg") String defg); Both request params mapped as IN message headers with names abcd and defg. The original MessageContentsList is preserved, even though it only contains the 2 parameters.
public Response doAction(@Multipart(value="body1") BusinessObject request, @Multipart(value="body2") BusinessObject request2); The first parameter is transferred as a header with name body1, and the second one is mapped as header body2. The original MessageContentsList is preserved as the IN message body.
public Response doAction(InputStream abcd); The InputStream is unwrapped from the MessageContentsList and preserved as the IN message body.
public Response doAction(DataHandler abcd); The DataHandler is unwrapped from the MessageContentsList and preserved as the IN message body.

More examples of the Simple Binding Style

Given a JAX-RS resource class with this method:
    @POST @Path("/customers/{type}")
    public Response newCustomer(Customer customer, @PathParam("type") String type, @QueryParam("active") @DefaultValue("true") boolean active) {
        return null;
    }
Serviced by the following route:
    from("cxfrs:bean:rsServer?bindingStyle=SimpleConsumer")
        .recipientList(simple("direct:${header.operationName}"));

    from("direct:newCustomer")
        .log("Request: type=${header.type}, active=${header.active}, customerData=${body}");
The following HTTP request with XML payload (given that the Customer DTO is JAXB-annotated):
POST /customers/gold?active=true

Payload:
<Customer>
  <fullName>Raul Kripalani</fullName>
  <country>Spain</country>
  <project>Apache Camel</project>
</Customer>
Will print the message:
Request: type=gold, active=true, customerData=<Customer.toString() representation>
For more examples on how to process requests and write responses can be found here.

Consuming a REST Request - Default Binding Style

CXF JAXRS front end implements the JAXRS(JSR311) API, so we can export the resources classes as a REST service. And we leverage the CXF Invoker API to turn a REST request into a normal Java object method invocation. Unlike the camel-restlet, you don't need to specify the URI template within your restlet endpoint, CXF take care of the REST request URI to resource class method mapping according to the JSR311 specification. All you need to do in Apache Camel is delegate this method request to a right processor or endpoint.
Here is an example of a CXFRS route:
private static final String CXF_RS_ENDPOINT_URI = "cxfrs://http://localhost:" + CXT + "/rest?resourceClasses=org.apache.camel.component.cxf.jaxrs.testbean.CustomerServiceResource";
 
 protected RouteBuilder createRouteBuilder() throws Exception {
    return new RouteBuilder() {
        public void configure() {
            errorHandler(new NoErrorHandlerBuilder());
            from(CXF_RS_ENDPOINT_URI).process(new Processor() {

                public void process(Exchange exchange) throws Exception {
                    Message inMessage = exchange.getIn();                        
                    // Get the operation name from in message
                    String operationName = inMessage.getHeader(CxfConstants.OPERATION_NAME, String.class);
                    if ("getCustomer".equals(operationName)) {
                        String httpMethod = inMessage.getHeader(Exchange.HTTP_METHOD, String.class);
                        assertEquals("Get a wrong http method", "GET", httpMethod);
                        String path = inMessage.getHeader(Exchange.HTTP_PATH, String.class);
                        // The parameter of the invocation is stored in the body of in message
                        String id = inMessage.getBody(String.class);
                        if ("/customerservice/customers/126".equals(path)) {                            
                            Customer customer = new Customer();
                            customer.setId(Long.parseLong(id));
                            customer.setName("Willem");
                            // We just put the response Object into the out message body
                            exchange.getOut().setBody(customer);
                        } else {
                            if ("/customerservice/customers/400".equals(path)) {
                                // We return the remote client IP address this time
                                org.apache.cxf.message.Message cxfMessage = inMessage.getHeader(CxfConstants.CAMEL_CXF_MESSAGE, org.apache.cxf.message.Message.class);
                                ServletRequest request = (ServletRequest) cxfMessage.get("HTTP.REQUEST");
                                String remoteAddress = request.getRemoteAddr();
                                Response r = Response.status(200).entity("The remoteAddress is " + remoteAddress).build();
                                exchange.getOut().setBody(r);
                                return;
                            }
                            if ("/customerservice/customers/123".equals(path)) {
                                 // send a customer response back
                                 Response r = Response.status(200).entity("customer response back!").build();
                                 exchange.getOut().setBody(r);
                                 return;
                            }
                            if ("/customerservice/customers/456".equals(path)) {
                                Response r = Response.status(404).entity("Can't found the customer with uri " + path).build();
                                throw new WebApplicationException(r);
                            } else {
                                throw new RuntimeCamelException("Can't found the customer with uri " + path);
                            }
                        }
                    }
                    if ("updateCustomer".equals(operationName)) {
                        assertEquals("Get a wrong customer message header", "header1;header2", inMessage.getHeader("test"));
                        String httpMethod = inMessage.getHeader(Exchange.HTTP_METHOD, String.class);
                        assertEquals("Get a wrong http method", "PUT", httpMethod);
                        Customer customer = inMessage.getBody(Customer.class);
                        assertNotNull("The customer should not be null.", customer);
                        // Now you can do what you want on the customer object
                        assertEquals("Get a wrong customer name.", "Mary", customer.getName());
                        // set the response back
                        exchange.getOut().setBody(Response.ok().build());
                }
                }
                
            });
        }
    };
}
The corresponding resource class used to configure the endpoint is defined as an interface:
@Path("/customerservice/")
public interface CustomerServiceResource {
 
    @GET
    @Path("/customers/{id}/")
    Customer getCustomer(@PathParam("id") String id);
 
    @PUT
    @Path("/customers/")
    Response updateCustomer(Customer customer);
 }

Important

The resource class is used to configure the JAXRS properties only. The methods will not be executed during the routing of messages to the endpoint, the route itself is responsible for all processing instead.

How to invoke the REST service through camel-cxfrs producer ?

CXF JAXRS front end implements a proxy based client API, with this API you can invoke the remote REST service through a proxy. camel-cxfrs producer is based on this proxy API. So, you just need to specify the operation name in the message header and prepare the parameter in the message body, camel-cxfrs producer will generate right REST request for you.
Here is an example
Exchange exchange = template.send("direct://proxy", new Processor() {

    public void process(Exchange exchange) throws Exception {
        exchange.setPattern(ExchangePattern.InOut);
        Message inMessage = exchange.getIn();
        setupDestinationURL(inMessage);
        // set the operation name 
        inMessage.setHeader(CxfConstants.OPERATION_NAME, "getCustomer");
        // using the proxy client API
        inMessage.setHeader(CxfConstants.CAMEL_CXF_RS_USING_HTTP_API, Boolean.FALSE);
        // set a customer header
        inMessage.setHeader("key", "value");
        // set the parameters , if you just have one parameter 
        // camel will put this object into an Object[] itself
        inMessage.setBody("123");
    }
    
});
     
// get the response message 
Customer response = (Customer) exchange.getOut().getBody();

assertNotNull("The response should not be null ", response);
assertEquals("Get a wrong customer id ", String.valueOf(response.getId()), "123");
assertEquals("Get a wrong customer name", response.getName(), "John");
assertEquals("Get a wrong response code", 200, exchange.getOut().getHeader(Exchange.HTTP_RESPONSE_CODE));
assertEquals("Get a wrong header value", "value", exchange.getOut().getHeader("key"));
CXF JAXRS front end also provides a http centric client API, You can also invoke this API from camel-cxfrs producer. You need to specify the HTTP_PATH and Http method and let the the producer know to use the HTTP centric client by using the URI option httpClientAPI or set the message header with CxfConstants.CAMEL_CXF_RS_USING_HTTP_API. You can turn the response object to the type class that you specify with CxfConstants.CAMEL_CXF_RS_RESPONSE_CLASS.
Exchange exchange = template.send("direct://http", new Processor() {

    public void process(Exchange exchange) throws Exception {
        exchange.setPattern(ExchangePattern.InOut);
        Message inMessage = exchange.getIn();
        setupDestinationURL(inMessage);
        // using the http central client API
        inMessage.setHeader(CxfConstants.CAMEL_CXF_RS_USING_HTTP_API, Boolean.TRUE);
        // set the Http method
        inMessage.setHeader(Exchange.HTTP_METHOD, "GET");
        // set the relative path
        inMessage.setHeader(Exchange.HTTP_PATH, "/customerservice/customers/123");                
        // Specify the response class , cxfrs will use InputStream as the response object type 
        inMessage.setHeader(CxfConstants.CAMEL_CXF_RS_RESPONSE_CLASS, Customer.class);
        // set a customer header
        inMessage.setHeader("key", "value");
        // since we use the Get method, so we don't need to set the message body
        inMessage.setBody(null);                
    }
    
});
     
// get the response message 
Customer response = (Customer) exchange.getOut().getBody();

assertNotNull("The response should not be null ", response);
assertEquals("Get a wrong customer id ", String.valueOf(response.getId()), "123");
assertEquals("Get a wrong customer name", response.getName(), "John");
assertEquals("Get a wrong response code", 200, exchange.getOut().getHeader(Exchange.HTTP_RESPONSE_CODE));
assertEquals("Get a wrong header value", "value", exchange.getOut().getHeader("key"));
From Apache Camel 2.1, we also support to specify the query parameters from CXFRS URI for the CXFRS HTTP centric client.
Exchange exchange = template.send("cxfrs://http://localhost:" + getPort2() + "/" + getClass().getSimpleName() + "/testQuery?httpClientAPI=true&q1=12&q2=13"
To support the Dynamical routing, you can override the URI's query parameters by using the CxfConstants.CAMEL_CXF_RS_QUERY_MAP header to set the parameter map for it.
Map<String, String> queryMap = new LinkedHashMap<String, String>();                    
queryMap.put("q1", "new");
queryMap.put("q2", "world");                    
inMessage.setHeader(CxfConstants.CAMEL_CXF_RS_QUERY_MAP, queryMap);

Chapter 24. DataFormat Component

Data Format Component

Available as of Camel 2.12
The dataformat: component allows to use Data Format as a Camel Component.

URI format

dataformat:name:(marshal|unmarshal)[?options]
Where name is the name of the Data Format. And then followed by the operation which must either be marshal or unmarshal. The options is used for configuring the Data Format in use. See the Data Format documentation for which options it support.

Samples

For example to use the JAXB Data Format we can do as follows:
from("activemq:My.Queue").
  to("dataformat:jaxb:unmarshal?contextPath=com.acme.model").
  to("mqseries:Another.Queue");
And in XML DSL you do:
<camelContext id="camel" xmlns="http://camel.apache.org/schema/spring">
  <route>
    <from uri="activemq:My.Queue"/>
    <to uri="dataformat:jaxb:unmarshal?contextPath=com.acme.model"/>
    <to uri="mqseries:Another.Queue"/>
  </route>
</camelContext>

Chapter 25. DataSet

DataSet Component

The DataSet component (available since 1.3.0) provides a mechanism to easily perform load & soak testing of your system. It works by allowing you to create DataSet instances both as a source of messages and as a way to assert that the data set is received.
Apache Camel will use the throughput logger when sending dataset's.

URI format

dataset:name[?options]
Where name is used to find the DataSet instance in the Registry
Apache Camel ships with a support implementation of org.apache.camel.component.dataset.DataSet, the org.apache.camel.component.dataset.DataSetSupport class, that can be used as a base for implementing your own DataSet. Apache Camel also ships with a default implementation, the org.apache.camel.component.dataset.SimpleDataSet that can be used for testing.

Options

Option Default Description
produceDelay 3 Allows a delay in ms to be specified, which causes producers to pause in order to simulate slow producers. Uses a minimum of 3 ms delay unless you set this option to -1 to force no delay at all.
consumeDelay 0 Allows a delay in ms to be specified, which causes consumers to pause in order to simulate slow consumers.
preloadSize 0 Sets how many messages should be preloaded (sent) before the route completes its initialization.
initialDelay 1000 Camel 2.1: Time period in millis to wait before starting sending messages.
minRate 0 Wait until the DataSet contains at least this number of messages
You can append query options to the URI in the following format, ?option=value&option=value&...

Configuring DataSet

Apache Camel will lookup in the Registry for a bean implementing the DataSet interface. So you can register your own DataSet as:
   <bean id="myDataSet" class="com.mycompany.MyDataSet">
      <property name="size" value="100"/>
   </bean>

Example

For example, to test that a set of messages are sent to a queue and then consumed from the queue without losing any messages:
// send the dataset to a queue
from("dataset:foo").to("activemq:SomeQueue");

// now lets test that the messages are consumed correctly
from("activemq:SomeQueue").to("dataset:foo");
The above would look in the Registry to find the foo DataSet instance which is used to create the messages.
Then you create a DataSet implementation, such as using the SimpleDataSet as described below, configuring things like how big the data set is and what the messages look like etc.

Properties on SimpleDataSet

Property Type Default Description
defaultBody Object <hello>world!</hello> Specifies the default message body. For SimpleDataSet it is a constant payload; though if you want to create custom payloads per message, create your own derivation of DataSetSupport.
reportCount long -1 Specifies the number of messages to be received before reporting progress. Useful for showing progress of a large load test. If < 0, then size / 5, if is 0 then size, else set to reportCount value.
size long 10 Specifies how many messages to send/consume.

Chapter 26. Direct

Direct Component

The direct: component provides direct, synchronous invocation of any consumers when a producer sends a message exchange. This endpoint can be used to connect existing routes in the same camel context.

Note

The Seda component provides asynchronous invocation of any consumers when a producer sends a message exchange.

Note

The VM component provides connections between Camel contexts as long they run in the same JVM.

URI format

direct:someName[?options]
Where someName can be any string to uniquely identify the endpoint

Options

Name Default Value Description
allowMultipleConsumers true @deprecated If set to false, then when a second consumer is started on the endpoint, an IllegalStateException is thrown. Will be removed in Camel 2.1: Direct endpoint does not support multiple consumers.
block false Camel 2.11.1: If sending a message to a direct endpoint which has no active consumer, then we can tell the producer to block and wait for the consumer to become active.
timeout 30000 Camel 2.11.1: The timeout value to use if block is enabled.
You can append query options to the URI in the following format, ?option=value&option=value&...

Samples

In the route below we use the direct component to link the two routes together:
from("activemq:queue:order.in")
    .to("bean:orderServer?method=validate")
    .to("direct:processOrder");

from("direct:processOrder")
    .to("bean:orderService?method=process")
    .to("activemq:queue:order.out");
And the sample using spring DSL:
   <route>
     <from uri="activemq:queue:order.in"/>
     <to uri="bean:orderService?method=validate"/>
     <to uri="direct:processOrder"/>
  </route>

  <route>
     <from uri="direct:processOrder"/>
     <to uri="bean:orderService?method=process"/>
     <to uri="activemq:queue:order.out"/>
  </route>
See also samples from the SEDA component, how they can be used together.

Chapter 27. Direct-VM

Direct VM Component

Available as of Camel 2.10
The direct-vm: component provides direct, synchronous invocation of any consumers in the JVM when a producer sends a message exchange. This endpoint can be used to connect existing routes in the same camel context, as well from other camel contexts in the same JVM.
This component differs from the Direct component in that Direct-VM supports communication across CamelContext instances - so you can use this mechanism to communicate across web applications (provided that camel-core.jar is on the system/boot classpath).
At runtime you can swap in new consumers, by stopping the existing consumer(s) and start new consumers. But at any given time there can be at most only one active consumer for a given endpoint.
This component allows also to connect routes deployed in different OSGI Bundles as you can see here after. Even if they are running in different bundles, the camel routes will use the same thread. That autorises to develop applications using Transactions - Tx.

URI format

direct-vm:someName
Where someName can be any string to uniquely identify the endpoint

Options

Name Default Value Description
block false Camel 2.11.1: If sending a message to a direct endpoint which has no active consumer, then we can tell the producer to block and wait for the consumer to become active.
timeout 30000 Camel 2.11.1: The timeout value to use if block is enabled.

Samples

In the route below we use the direct component to link the two routes together:
from("activemq:queue:order.in")
    .to("bean:orderServer?method=validate")
    .to("direct-vm:processOrder");
And now in another CamelContext, such as another OSGi bundle
from("direct-vm:processOrder")
    .to("bean:orderService?method=process")
    .to("activemq:queue:order.out");
And the sample using spring DSL:
   <route>
     <from uri="activemq:queue:order.in"/>
     <to uri="bean:orderService?method=validate"/>
     <to uri="direct-vm:processOrder"/>
  </route>

  <route>
     <from uri="direct-vm:processOrder"/>
     <to uri="bean:orderService?method=process"/>
     <to uri="activemq:queue:order.out"/>
  </route>

Chapter 28. Disruptor

Disruptor Component

Available as of Camel 2.12
The disruptor: component provides asynchronous SEDA behavior much as the standard SEDA Component, but utilizes a Disruptor instead of a BlockingQueue utilized by the standard SEDA. Alternatively, a
disruptor-vm: endpoint is supported by this component, providing an alternative to the standard VM. As with the SEDA component, buffers of the disruptor: endpoints are only visible within a single CamelContext and no support is provided for persistence or recovery. The buffers of the *disruptor-vm:* endpoints also provides support for communication across CamelContexts instances so you can use this mechanism to communicate across web applications (provided that camel-disruptor.jar is on the system/boot classpath).
The main advantage of choosing to use the Disruptor Component over the SEDA or the VM Component is performance in use cases where there is high contention between producer(s) and/or multicasted or concurrent Consumers. In those cases, significant increases of throughput and reduction of latency has been observed. Performance in scenarios without contention is comparable to the SEDA and VM Components.
The Disruptor is implemented with the intention of mimicing the behaviour and options of the SEDA and VM Components as much as possible. The main differences with the them are the following:
  • The buffer used is always bounded in size (default 1024 exchanges).
  • As a the buffer is always bouded, the default behaviour for the Disruptor is to block while the buffer is full instead of throwing an exception. This default behaviour may be configured on the component (see options).
  • The Disruptor enpoints don't implement the BrowsableEndpoint interface. As such, the exchanges currently in the Disruptor can't be retrieved, only the amount of exchanges.
  • The Disruptor requires its consumers (multicasted or otherwise) to be statically configured. Adding or removing consumers on the fly requires complete flushing of all pending exchanges in the Disruptor.
  • As a result of the reconfiguration: Data sent over a Disruptor is directly processed and 'gone' if there is at least one consumer, late joiners only get new exchanges published after they've joined.
  • The pollTimeout option is not supported by the Disruptor Component.
  • When a producer blocks on a full Disruptor, it does not respond to thread interrupts.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-disruptor</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

 disruptor:someName[?options]
or
 disruptor-vm:someName[?options]
Where *someName* can be any string that uniquely identifies the endpoint within the current CamelContext (or across contexts in case of *disruptor-vm:*). You can append query options to the URI in the following format:
  ?option=value&option=value&...

Options

All the following options are valid for both the *disruptor:* and *disruptor-vm:* components.
Name Default Description
size 1024 The maximum capacity of the Disruptors ringbuffer. Will be effectively increased to the nearest power of two. Notice: Mind if you use this option, then its the first endpoint being created with the queue name, that determines the size. To make sure all endpoints use same size, then configure the size option on all of them, or the first endpoint being created.
bufferSize Component only: The maximum default size (capacity of the number of messages it can hold) of the Disruptors ringbuffer. This option is used if size is not in use.
queueSize Component only: Additional option to specify the <em>bufferSize</em> to maintain maximum compatibility with the SEDA Component.
concurrentConsumers 1 Number of concurrent threads processing exchanges.
waitForTaskToComplete IfReplyExpected Option to specify whether the caller should wait for the async task to complete or not before continuing. The following three options are supported: Always, Never or IfReplyExpected. The first two values are self-explanatory. The last value, IfReplyExpected, will only wait if the message is Request Reply based. See more information about Async messaging.
timeout 30000 Timeout (in milliseconds) before a producer will stop waiting for an asynchronous task to complete. See waitForTaskToComplete and Async for more details. You can disable timeout by using 0 or a negative value.
defaultMultipleConsumers Component only: Allows to set the default allowance of multiple consumers for endpoints created by this comonent used when multipleConsumers is not provided.
limitConcurrentConsumers true Whether to limit the number of concurrentConsumers to the maximum of 500. By default, an exception will be thrown if a Disruptor endpoint is configured with a greater number. You can disable that check by turning this option off.
blockWhenFull true Whether a thread that sends messages to a full Disruptor will block until the ringbuffer's capacity is no longer exhausted. By default, the calling thread will block and wait until the message can be accepted. By disabling this option, an exception will be thrown stating that the queue is full.
defaultBlockWhenFull Component only: Allows to set the default producer behaviour when the ringbuffer is full for endpoints created by this comonent used when blockWhenFull is not provided.
waitStrategy Blocking Defines the strategy used by consumer threads to wait on new exchanges to be published. The options allowed are:Blocking, Sleeping, BusySpin and Yielding. Refer to the section below for more information on this subject
defaultWaitStrategy Component only: Allows to set the default wait strategy for endpoints created by this comonent used when waitStrategy is not provided.
producerType Multi
Defines the producers allowed on the Disruptor. The options allowed are: Multi to allow multiple producers and Single to enable certain optimizations only allowed when one concurrent producer (on one thread or otherwise synchronized) is active.

Wait strategies

The wait strategy effects the type of waiting performed by the consumer threads that are currently waiting for the next exchange to be published. The following strategies can be chosen:
Name Description Advice
Blocking Blocking strategy that uses a lock and condition variable for Consumers waiting on a barrier. This strategy can be used when throughput and low-latency are not as important as CPU resource.
Sleeping Sleeping strategy that initially spins, then uses a Thread.yield(), and eventually for the minimum number of nanos the OS and JVM will allow while the Consumers are waiting on a barrier. This strategy is a good compromise between performance and CPU resource. Latency spikes can occur after quiet periods.
BusySpin Busy Spin strategy that uses a busy spin loop for Consumers waiting on a barrier. This strategy will use CPU resource to avoid syscalls which can introduce latency jitter. It is best used when threads can be bound to specific CPU cores.
Yielding Yielding strategy that uses a Thread.yield() for Consumers waiting on a barrier after an initially spinning. This strategy is a good compromise between performance and CPU resource without incurring significant latency spikes.

Use of Request Reply

The Disruptor component supports using Request Reply, where the caller will wait for the Async route to complete. For instance:
from("mina:tcp://0.0.0.0:9876?textline=true&sync=true").to("disruptor:input");
from("disruptor:input").to("bean:processInput").to("bean:createResponse");
In the route above, we have a TCP listener on port 9876 that accepts incoming requests. The request is routed to the disruptor:input buffer. As it is a Request Reply message, we wait for the response. When the consumer on the disruptor:input buffer is complete, it copies the response to the original message response.

Concurrent consumers

By default, the Disruptor endpoint uses a single consumer thread, but you can configure it to use concurrent consumer threads. So instead of thread pools you can use:
from("disruptor:stageName?concurrentConsumers=5").process(...)
As for the difference between the two, note a thread pool can increase/shrink dynamically at runtime depending on load, whereas the number of concurrent consumers is always fixed and supported by the Disruptor internally so performance will be higher.

Thread pools

Be aware that adding a thread pool to a Disruptor endpoint by doing something like:
from("disruptor:stageName").thread(5).process(...)
Can wind up with adding a normal BlockingQueue to be used in conjunction with the Disruptor, effectively negating part of the performance gains achieved by using the Disruptor. Instead, it is advices to directly configure number of threads that process messages on a Disruptor endpoint using the concurrentConsumers option.

Sample

In the route below we use the Disruptor to send the request to this async queue to be able to send a fire-and-forget message for further processing in another thread, and return a constant reply in this thread to the original caller.
public void configure() throws Exception {
    from("direct:start")
        // send it to the disruptor that is async
        .to("disruptor:next")
        // return a constant response
        .transform(constant("OK"));

    from("disruptor:next").to("mock:result");
}
Here we send a Hello World message and expects the reply to be OK.
Object out = template.requestBody("direct:start", "Hello World");
assertEquals("OK", out);
The "Hello World" message will be consumed from the Disruptor from another thread for further processing. Since this is from a unit test, it will be sent to a mock endpoint where we can do assertions in the unit test.

Using multipleConsumers

In this example we have defined two consumers and registered them as spring beans.
<!-- define the consumers as spring beans -->
<bean id="consumer1" class="org.apache.camel.spring.example.FooEventConsumer"/>

<bean id="consumer2" class="org.apache.camel.spring.example.AnotherFooEventConsumer"/>

<camelContext xmlns="http://camel.apache.org/schema/spring">
    <!-- define a shared endpoint which the consumers can refer to instead of using url -->
    <endpoint id="foo" uri="disruptor:foo?multipleConsumers=true"/>
</camelContext>
Since we have specified multipleConsumers=true on the Disruptor foo endpoint we can have those two or more consumers receive their own copy of the message as a kind of pub-sub style messaging. As the beans are part of an unit test they simply send the message to a mock endpoint, but notice how we can use @Consume to consume from the Disruptor.
public class FooEventConsumer {

    @EndpointInject(uri = "mock:result")
    private ProducerTemplate destination;

    @Consume(ref = "foo")
    public void doSomething(String body) {
        destination.sendBody("foo" + body);
    }

}

Extracting disruptor information

If needed, information such as buffer size, etc. can be obtained without using JMX in this fashion:
DisruptorEndpoint disruptor = context.getEndpoint("disruptor:xxxx");
int size = disruptor.getBufferSize();

Chapter 29. DNS

DNS

Available as of Camel 2.7
This is an additional component for Camel to run DNS queries, using DNSJava. The component is a thin layer on top of DNSJava. The component offers the following operations:
ip
To resolve a domain by its IP address.
lookup
To look up information about the domain.
dig
To run DNS queries.

Requires SUN JVM

The DNSJava library requires running on the SUN JVM. If you use Apache ServiceMix or Apache Karaf, you'll need to adjust the etc/jre.properties file, to add sun.net.spi.nameservice to the list of Java platform packages exported. The server will need restarting before this change takes effect.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-dns</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

The URI scheme for a DNS component is as follows
dns://operation
This component only supports producers.

Options

None.

Headers

Header Type Operations Description
dns.domain String ip The domain name. Mandatory.
dns.name String lookup The name to lookup. Mandatory.
dns.type - lookup, dig The type of the lookup. Should match the values of org.xbill.dns.Type. Optional.
dns.class - lookup, dig he DNS class of the lookup. Should match the values of org.xbill.dns.DClass. Optional.
dns.query String dig The query itself. Mandatory.
dns.server String dig The server in particular for the query. If none is given, the default one specified by the OS will be used. Optional.

Examples

IP lookup

        <route id="IPCheck">
            <from uri="direct:start"/>
            <to uri="dns:ip"/>
        </route>
This looks up a domain's IP. For example, www.example.com resolves to 192.0.32.10. The IP address to lookup must be provided in the header with key "dns.domain".

DNS lookup

        <route id="IPCheck">
            <from uri="direct:start"/>
            <to uri="dns:lookup"/>
        </route>
This returns a set of DNS records associated with a domain. The name to lookup must be provided in the header with key "dns.name".

DNS Dig

Dig is a Unix command-line utility to run DNS queries.
        <route id="IPCheck">
            <from uri="direct:start"/>
            <to uri="dns:dig"/>
        </route>
The query must be provided in the header with key "dns.query".

Chapter 30. EJB

EJB Component

Available as of Apache Camel 2.4
The ejb: component binds EJBs to message exchanges.

URI format

ejb:ejbName[?options]

Where ejbName can be any string which is used to look up the EJB in the Application Server JNDI Registry

Options

Name Type Default Description
method String null The method name that bean will be invoked. If not provided, Apache Camel will try to pick the method itself. In case of ambiguity an exception is thrown. See Bean Binding for more details.
multiParameterArray boolean false How to treat the parameters which are passed from the message body; if it is true, the In message body should be an array of parameters.
You can append query options to the URI in the following format, ?option=value&option=value&...
The EJB component extends the Bean component in which most of the details from the Bean component applies to this component as well.

Bean Binding

How bean methods to be invoked are chosen (if they are not specified explicitly through the method parameter) and how parameter values are constructed from the MessageMessage are all defined by the Bean Binding mechanism which is used throughout all of the various Bean Integration mechanisms in Apache Camel.

Examples

In the following examples we use the Greater EJB which is defined as follows:
public interface GreaterLocal {

    String hello(String name);

    String bye(String name);

}
And the implementation
@Stateless
public class GreaterImpl implements GreaterLocal {

    public String hello(String name) {
        return "Hello " + name;
    }

    public String bye(String name) {
        return "Bye " + name;
    }

}

Using Java DSL

In this example we want to invoke the hello method on the EJB. Since this example is based on an unit test using Apache OpenEJB we have to set a JndiContext on the EJB component with the OpenEJB settings.
@Override
protected CamelContext createCamelContext() throws Exception {
    CamelContext answer = new DefaultCamelContext();

    // enlist EJB component using the JndiContext
    EjbComponent ejb = answer.getComponent("ejb", EjbComponent.class);
    ejb.setContext(createEjbContext());

    return answer;
}

private static Context createEjbContext() throws NamingException {
    // here we need to define our context factory to use OpenEJB for our testing
    Properties properties = new Properties();
    properties.setProperty(Context.INITIAL_CONTEXT_FACTORY, "org.apache.openejb.client.LocalInitialContextFactory");

    return new InitialContext(properties);
}
Then we are ready to use the EJB in the Apache Camel route:
from("direct:start")
    // invoke the greeter EJB using the local interface and invoke the hello method
    .to("ejb:GreaterImplLocal?method=hello")
    .to("mock:result");

Note

In a real application server you most likely do not have to setup a JndiContext on the EJB component as it will create a default JndiContext on the same JVM as the application server, which usually allows it to access the JNDI registry and lookup the EJBs. However if you need to access a application server on a remote JVM or the likes, you have to prepare the properties beforehand.

Using Spring XML

And this is the same example using Spring XML instead:
Again since this is based on an unit test we need to setup the EJB component:
<!-- setup Camel EJB component -->
<bean id="ejb" class="org.apache.camel.component.ejb.EjbComponent">
    <property name="properties" ref="jndiProperties"/>
</bean>

<!-- use OpenEJB context factory -->
<p:properties id="jndiProperties">
    <prop key="java.naming.factory.initial">org.apache.openejb.client.LocalInitialContextFactory</prop>
</p:properties>
Before we are ready to use EJB in the Apache Camel routes:
<camelContext xmlns="http://camel.apache.org/schema/spring">
    <route>
        <from uri="direct:start"/>
        <to uri="ejb:GreaterImplLocal?method=hello"/>
        <to uri="mock:result"/>
    </route>
</camelContext>

Chapter 31. ElasticSearch

ElasticSearch Component

Available as of Camel 2.11
The ElasticSearch component allows you to interface with an ElasticSearch server.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-elasticsearch</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

elasticsearch://clusterName?[options]

Tip

if you want to run against a local (in JVM/classloader) ElasticSearch server, just set the clusterName value in the URI to local. See the client guide for more details.

Endpoint Options

The following options may be configured on the ElasticSearch endpoint. All are required to be set as either an endpoint URI parameter or as a header (headers override endpoint properties)
name description
operation required, indicates the operation to perform
indexName
the name of the index to act against
ip
the TransportClient remote host ip to use Camel 2.12

Message Operations

The following ElasticSearch operations are currently supported. Simply set an endpoint URI option or exchange header with a key of operation and a value set to one of the following. Some operations also require other parameters or the message body to be set.
operation message body description
INDEX Map, String, byte[] or XContentBuilder content to index adds content to an index and returns the content's indexId in the body
GET_BY_ID index id of content to retrieve retrieves the specified index and returns a GetResult object in the body
DELETE index id of content to delete deletes the specified indexId and returns a DeleteResult object in the body

Index Example

Below is a simple INDEX example
from("direct:index")
    .to("elasticsearch://local?operation=INDEX&indexName=twitter&indexType=tweet");
<route>
    <from uri="direct:index" />
    <to uri="elasticsearch://local?operation=INDEX&indexName=twitter&indexType=tweet"/>
</route>
A client would simply need to pass a body message containing a Map to the route. The result body contains the indexId created.
Map<String, String> map = new HashMap<String, String>();
map.put("content", "test");
String indexId = template.requestBody("direct:index", map, String.class);

For more information, see these resources

Chapter 32. EventAdmin

EventAdmin component

Available in Camel 2.6
The eventadmin component can be used in an OSGi environment to receive OSGi EventAdmin events and process them.

Dependencies

Maven users need to add the following dependency to their pom.xml
<dependency>
  <groupId>org.apache.camel</groupId>
  <artifactId>camel-eventadmin</artifactId>
  <version>${camel-version}</version>
</dependency>
where ${camel-version} must be replaced by the actual version of Camel (2.6.0 or higher).

URI format

eventadmin:topic[?options]
where topic is the name of the topic to listen too.

URI options

Name Default value Description
send false Whether to use 'send' or 'synchronous' deliver. Default false (async delivery)

Message headers

Name Type Message Description

Message body

The in message body will be set to the received Event.

Example usage

<route>
    <from uri="eventadmin:*"/>
    <to uri="stream:out"/>
</route>

Chapter 33. Exec

Exec component

Available in Apache Camel 2.3
The exec component can be used to execute system commands.

Dependencies

Maven users need to add the following dependency to their pom.xml
<dependency>
  <groupId>org.apache.camel</groupId>
  <artifactId>camel-exec</artifactId>
  <version>${camel-version}</version>
</dependency>
where ${camel-version} must be replaced by the actual version of Apache Camel (2.3.0 or higher).

URI format

exec://executable[?options]
where executable is the name, or file path, of the system command that will be executed. If executable name is used (e.g. exec:java), the executable must in the system path.

URI options

Name Default value Description
args null
The arguments of the executable. The arguments may be one or many whitespace-separated tokens, that can be quoted with ", e.g. args="arg 1" arg2 will use two arguments arg 1 and arg2. To include the quotes use "", e.g. args=""arg 1"" arg2 will use the arguments "arg 1" and arg2.
workingDir null The directory in which the command should be executed. If null, the working directory of the current process will be used.
timeout Long.MAX_VALUE The timeout, in milliseconds, after which the executable should be terminated. If execution has has not finished within the timeout, the component will send a termination request.
outFile null The name of a file, created by the executable, that should be considered as its output. If no outFile is set, the standard output (stdout) of the executable will be considered as output.
binding a DefaultExecBinding instance A reference to a org.apache.commons.exec.ExecBinding in the Registry.
commandExecutor a DefaultCommandExecutor instance A reference to a org.apache.commons.exec.ExecCommandExecutor in the Registry, that customizes the command execution. The default command executor utilizes the commons-exec library. It adds a shutdown hook for every executed command.
useStderrOnEmptyStdout false A boolean indicating that when stdout is empty, this component will populate the Camel Message Body with stderr. This behavior is disabled (false) by default.

Message headers

The supported headers are defined in org.apache.camel.component.exec.ExecBinding.
Name Type Message Description
ExecBinding.EXEC_COMMAND_EXECUTABLE String in The name of the system command that will be executed. Overrides the executable in the URI.
ExecBinding.EXEC_COMMAND_ARGS java.util.List<String> in The arguments of the executable. The arguments are used literally, no quoting is applied. Overrides existing args in the URI.
ExecBinding.EXEC_COMMAND_ARGS String in Camel 2.5: The arguments of the executable as a Single string where each argument is whitespace separated (see args in URI option). The arguments are used literally, no quoting is applied. Overrides existing args in the URI.
ExecBinding.EXEC_COMMAND_OUT_FILE String in The name of a file, created by the executable, that should be considered as output of the executable. Overrides existing outFile in the URI.
ExecBinding.EXEC_COMMAND_TIMEOUT long in The timeout, in milliseconds, after which the executable should be terminated. Overrides any existing timeout in the URI.
ExecBinding.EXEC_COMMAND_WORKING_DIR String in The directory in which the command should be executed. Overrides any existing workingDir in the URI.
ExecBinding.EXEC_EXIT_VALUE int out The value of this header is the exit value of the executable. Non-zero exit values typically indicate abnormal termination. Note that the exit value is OS-dependent.
ExecBinding.EXEC_STDERR java.io.InputStream out The value of this header points to the standard error stream (stderr) of the executable. If no stderr is written, the value is null.
ExecBinding.EXEC_USE_STDERR_ON_EMPTY_STDOUT boolean in Indicates that when stdout is empty, this component will populate the Camel Message Body with stderr. This behavior is disabled (false) by default.

Message body

If the Exec component receives an in message body that is convertible to java.io.InputStream, it is used to feed input to the executable via its stdin. After execution, the message body is the result of the execution, that is, an org.apache.camel.components.exec.ExecResult instance containing the stdout, stderr, exit value, and out file. This component supports the following ExecResult type converters for convenience:
From To
ExecResult java.io.InputStream
ExecResult String
ExecResult byte []
ExecResult org.w3c.dom.Document

Executing word count (Linux)

The example below executes wc (word count, Linux) to count the words in file /usr/share/dict/words. The word count (output) is written in the standart output stream of wc.
from("direct:exec")
.to("exec:wc?args=--words /usr/share/dict/words")
.process(new Processor() {
     public void process(Exchange exchange) throws Exception {
       // By default, the body is ExecResult instance
       assertIsInstanceOf(ExecResult.class, exchange.getIn().getBody());
       // Use the Camel Exec String type converter to convert the ExecResult to String
       // In this case, the stdout is considered as output
       String wordCountOutput = exchange.getIn().getBody(String.class);
       // do something with the word count
     }
});

Executing java

The example below executes java with 2 arguments: -server and -version, provided that java is in the system path.
from("direct:exec")
.to("exec:java?args=-server -version")
The example below executes java in c:/temp with 3 arguments: -server, -version and the sytem property user.name.
from("direct:exec")
.to("exec:c:/program files/jdk/bin/java?args=-server -version -Duser.name=Camel&workingDir=c:/temp")

Executing Ant scripts

The following example executes Apache Ant (Windows only) with the build file CamelExecBuildFile.xml, provided that ant.bat is in the system path, and that CamelExecBuildFile.xml is in the current directory.
from("direct:exec")
.to("exec:ant.bat?args=-f CamelExecBuildFile.xml")
In the next example, the ant.bat command redirects its output to CamelExecOutFile.txt with -l. The file CamelExecOutFile.txt is used as the out file with outFile=CamelExecOutFile.txt. The example assumes that ant.bat is in the system path, and that CamelExecBuildFile.xml is in the current directory.
from("direct:exec")
.to("exec:ant.bat?args=-f CamelExecBuildFile.xml -l CamelExecOutFile.txt&outFile=CamelExecOutFile.txt")
.process(new Processor() {
     public void process(Exchange exchange) throws Exception {
        InputStream outFile = exchange.getIn().getBody(InputStream.class);
        assertIsInstanceOf(InputStream.class, outFile);
        // do something with the out file here
     }
  });

Executing echo (Windows)

Commands such as echo and dir can be executed only with the command interpreter of the operating system. This example shows how to execute such a command - echo - in Windows.
from("direct:exec").to("exec:cmd?args=/C echo echoString")

Chapter 34. Fabric Component

Abstract

The Fabric component implements a location discovery mechanism for Apache Camel endpoints. This mechanism can also be used to provide load-balancing over a cluster of endpoints. On the client side (producer endpoints), endpoints are represented by an abstract ID and at run time, the ID is resolved to a specific endpoint URI. Because the URI is stored in a distributed registry (provided by Fuse Fabric), this enables you to create flexible applications whose topology can be specified at deploy time and updated dynamically.

Dependencies

The Fabric component can only be used in the context of a fabric-enabled Red Hat JBoss Fuse container. You must ensure that the fabric-camel feature is installed. If necessary, you can install it using the following console command:
karaf@root> features:install fabric-camel
Alternatively, if you decide to use a custom feature to deploy your application, you can ensure that the fabric-camel feature is installed by including it in your feature definition. For example:
<?xml version="1.0" encoding="UTF-8"?>
<features>
    <feature name="fabric-component-example">
        <feature>fabric-camel</feature>
        <bundle>URIforMyBundle</bundle>
        <!-- Specify any other required bundles or features -->
        ...
    </feature>
</features>
For more details about features, see Deploying Features.

URI format

A fabric endpoint has the following URI format:
fabric:ClusterID[:PublishedURI[?Options]]
The format of the URI depends on whether it is used to specify a consumer endpoint or a producer endpoint.
For a Fabric producer endpoint, the URI format is:
fabric:ClusterID:PublishedURI[?Options]
Where the specified URI, PublishedURI, is published in the fabric registry and associated with the ClusterId cluster. The options, Options, are used when creating the producer endpoint instance, but the options are not published with the PublishedURI in the fabric registry.
For a Fabric consumer endpoint, the URI format is:
fabric:ClusterID
Where the client looks up the ID, ClusterId, in the fabric registry to discover the URI to connect to.

URI options

The Fabric component itself does not support any URI options. It is possible, however, to specify options for the published URI. These options are stored in the fabric registry as part of the URI and are used as follows:
  • Server-only options—options that are applicable only to the server are applied to the server endpoint (consumer endpoint) at run time.
  • Client-only options—options that are applicable only to the client are applied to the client endpoint (producer endpoint) at run time.
  • Common options—options common to the client and the server are applied to both.

Use cases for fabric endpoints

Fabric endpoints essentially provide a discovery mechanism for Apache Camel endpoints. For example, they support the following basic use cases:

Location discovery

Figure 34.1, “Location Discovery through Fabric” gives an overview of how Fabric endpoints enable location discovery at run time.
Location Discovery through Fabric

Figure 34.1. Location Discovery through Fabric

The server side of this application is defined by a route that starts with a Fabric endpoint, where the Fabric endpoint publishes the URI, jetty:http://0.0.0.0:9090. When this route is started, it automatically registers the Jetty URI in the fabric registry, under the cluster ID, foo.
The client side of the application is defined by a route that ends with the Fabric endpoint, fabric:foo. Now, when the client route starts, it automatically looks up the ID, foo, in the fabric registry and retrieves the associated Jetty endpoint URI. The client then creates a producer endpoint using the discovered Jetty URI and connects to the corresponding server port.

Load-balancing cluster

Figure 34.2, “Load Balancing through Fabric” gives an overview of how Fabric endpoints enable you to create a load-balancing cluster.
Load Balancing through Fabric

Figure 34.2. Load Balancing through Fabric

In this case, two Jetty servers are created, with the URIs, jetty:http://0.0.0.0:9090 and jetty:http://0.0.0.0:9191. Because these published URIs are both prefixed by fabric:foo:, both of the Jetty URIs are registered under the same cluster ID, foo, in the fabric registry.
Now, when the client routes starts, it automatically looks up the ID, foo, in the fabric registry. Because the foo ID is associated with multiple endpoint URIs, fabric implements a random load balancing algorithm to choose one of the available URIs. The client then creates a producer endpoint, using the chosen URI.

Auto-reconnect feature

Fabric endpoints support auto-reconnection. So, if a client endpoint (producer endpoint) loses its connection to a server endpoint, it will automatically go back to the fabric registry, ask for another URI, and then connect to the new URI.

Publishing an endpoint URI

To publish an endpoint URI, PublishedURI, in the fabric registry, define a fabric endpoint with the publisher syntax, FabricScheme:ClusterID:PublishedURI. Note that this syntax can only be used in a consumer endpoint (that is, an endpoint that appears in a from DSL command).
Example 34.1, “Publishing a URI ” shows a route that implements a Jetty HTTP server, where the Jetty URI is published to the fabric registry under the ID, cluster. The route is a simply HTTP server that returns the constant message, Response from Zookeeper agent, in the body of the HTTP response.

Example 34.1. Publishing a URI

<?xml version="1.0" encoding="UTF-8"?>
<blueprint xmlns="http://www.osgi.org/xmlns/blueprint/v1.0.0"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xsi:schemaLocation="
           http://www.osgi.org/xmlns/blueprint/v1.0.0
           http://www.osgi.org/xmlns/blueprint/v1.0.0/blueprint.xsd">

 <reference id="curator" interface="org.apache.curator.framework.CuratorFramework"/>

    <bean id="fabric-camel" class="io.fabric8.camel.FabricComponent">
        <property name="curator" ref="curator"/>
    </bean>

    <camelContext id="camel" trace="false" xmlns="http://camel.apache.org/schema/blueprint">
        <route id="fabric-server">
            <from uri="fabric-camel:cluster:jetty:http://0.0.0.0:9090/fabric"/>
            <log message="Request received : ${body}"/>
            <setHeader headerName="karaf.name">
                <simple>${sys.karaf.name}</simple>
            </setHeader>
            <transform>
                <simple>Response from Zookeeper agent</simple>
            </transform>
        </route>
    </camelContext>

</blueprint>
Note the following points about the preceding sample:
  • A reference to the org.apache.curator.framework.CuratorFramework OSGi service is created using the reference element. Apache Curator is a ZooKeeper client component that manages connections to the ZooKeeper server, providing a high quality of service (including automatic reconnection).

    Note

    The CuratorFramework OSGi service is provided by the fabric agent. Hence, a fabric agent must already be installed and running in the container where the route is deployed.
  • The Fabric component uses the CuratorFramework object to connect to the ZooKeeper server (Fabric registry).
  • The from DSL command defines the fabric URI, fabric-camel:cluster:jetty:http://0.0.0.0:9090/fabric. At run time, this causes two things to happen:
    • The specified jetty URI is published to the fabric registry under the cluster ID, cluster.
    • The Jetty endpoint is activated and used as the consumer endpoint of the route (just as if it had been specified without the fabric-camel:cluster: prefix).
Because the route is implemented in blueprint XML, you would normally add the file containing this code to the src/main/resources/OSGI-INF/blueprint directory of a Maven project.

Looking up an endpoint URI

To look up a URI in the fabric registry, simply specify the fabric endpoint URI with an ID, in the format, FabricScheme:ClusterID. This syntax is used in a producer endpoint (for example, an endpoint that appears in a to DSL command).
Example 34.2, “Looking up a URI” shows a route that implements a HTTP client, where the HTTP endpoint is discovered dynamically at run time, by looking up the specified ID, cluster, in the fabric registry.

Example 34.2. Looking up a URI

<?xml version="1.0" encoding="UTF-8"?>
<blueprint xmlns="http://www.osgi.org/xmlns/blueprint/v1.0.0"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xsi:schemaLocation="
           http://www.osgi.org/xmlns/blueprint/v1.0.0
           http://www.osgi.org/xmlns/blueprint/v1.0.0/blueprint.xsd">

 <reference id="curator" interface="org.apache.curator.framework.CuratorFramework"/>

  <bean id="fabric-camel" class="io.fabric8.camel.FabricComponent">
    <property name="curator" ref="curator"/>
  </bean>

  <camelContext id="camel" trace="false" xmlns="http://camel.apache.org/schema/blueprint">

    <route id="fabric-client">
      <from uri="timer://foo?fixedRate=true&amp;period=10000"/>
      <setBody>
          <simple>Hello from Zookeeper server</simple>
      </setBody>
      <to uri="fabric-camel:cluster"/>
      <log message=">>> ${body} : ${header.karaf.name}"/>
    </route>

  </camelContext>

  <reference interface="org.apache.camel.spi.ComponentResolver"
              filter="(component=jetty)"/>

</blueprint>
The client route also needs a reference to the org.apache.curator.framework.CuratorFramework OSGi service, which the Fabric component uses to connect to the underlying fabric.
Because the route is implemented in blueprint XML, you would normally add the file containing this code to the src/main/resources/OSGI-INF/blueprint directory of a Maven project.

Load-balancing example

In principle, implementing load balancing is easy using fabric endpoints. All that you have to do is to publish more than one endpoint URI under the same cluster ID. Now, when a client looks up that cluster ID, it gets a random selection out of the list of available endpoint URIs.
The servers in the load-balancing cluster have almost the same configuration. Essentially, the only difference between them is that they publish an endpoint URI with a different hostname and/or IP port. Instead of creating a separate OSGi bundle for every single server in the load-balancing cluster, however, it is better to define a template that enables you to specify the host or port using a configuration variable.
Example 34.3, “Server Template for a Load-Balancing Cluster” illustrates the template approach to defining servers in a load-balancing cluster.

Example 34.3. Server Template for a Load-Balancing Cluster

<?xml version="1.0" encoding="UTF-8"?>
<blueprint xmlns="http://www.osgi.org/xmlns/blueprint/v1.0.0"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xmlns:cm="http://aries.apache.org/blueprint/xmlns/blueprint-cm/v1.0.0"
           xsi:schemaLocation="
           http://www.osgi.org/xmlns/blueprint/v1.0.0
           http://www.osgi.org/xmlns/blueprint/v1.0.0/blueprint.xsd">

    <!-- osgi blueprint property placeholder -->
    <cm:property-placeholder
        id="myConfig"
        persistent-id="io.fabric8.examples.camel.loadbalancing.server"/>

    <reference id="curator" interface="org.apache.curator.framework.CuratorFramework"/>

    <bean id="fabric-camel" class="io.fabric8.camel.FabricComponent">
        <property name="curator" ref="curator"/>
    </bean>

    <camelContext id="camel" trace="false" xmlns="http://camel.apache.org/schema/blueprint">
        <!-- using Camel properties component and refer
             to the blueprint property placeholder by its id -->
        <propertyPlaceholder id="properties"
                             location="blueprint:myConfig"
                             prefixToken="[[" suffixToken="]]"/>

        <route id="fabric-server">
            <from uri="fabric-camel:cluster:jetty:http://0.0.0.0:[[portNumber]]/fabric"/>
            <log message="Request received : ${body}"/>
            <setHeader headerName="karaf.name">
                <simple>${sys.karaf.name}</simple>
            </setHeader>
            <transform>
                <simple>Response from Zookeeper agent</simple>
            </transform>
        </route>
    </camelContext>

</blueprint>
First of all, you need to initialize the OSGi blueprint property placeholder. The property placeholder mechanism enables you to read property settings from the OSGi Config Admin service and substitute the properties in the blueprint configuration file. In this example, the property placeholder accesses properties from the io.fabric8.examples.camel.loadbalancing.server persistent ID. A persistent ID in the OSGi Config Admin service identifies a collection of related property settings. After initializing the property placeholder, you can access any property values from the persistent ID using the syntax, [[PropName]].
The Fabric endpont URI exploits the property placeholder mechanism to substitute the value of the Jetty port, [[portNumber]], at run time. At deploy time, you can specify the value of the portName property. For example, if using a custom feature, you could specify the property in the feature definition (see Add OSGi configurations to the feature). Alternatively, you can specify configuration properties when defining deployment profiles in the Fuse Management Console.

OSGi bundle plug-in configuration

When defining an OSGi bundle that uses Fabric endpoints, the Import-Package bundle header must be configured to import the following Java packages:
io.fabric8.zookeeper.spring
io.fabric8.zookeeper
For example, assuming that you use Maven to build your application, Example 34.4, “Maven Bundle Plug-In Configuration” shows how you can configure the Maven bundle plug-in to import the required packages.

Example 34.4. Maven Bundle Plug-In Configuration

<project ... >
  ...
  <build>
    <defaultGoal>install</defaultGoal>
    <plugins>
      ...
      <plugin>
        <groupId>org.apache.felix</groupId>
        <artifactId>maven-bundle-plugin</artifactId>
        <extensions>true</extensions>
        <configuration>
          <instructions>
            <Bundle-SymbolicName>${project.groupId}.${project.artifactId}</Bundle-SymbolicName>
            <Import-Package>
              io.fabric8.zookeeper.spring,
              io.fabric8.zookeeper,
              *
            </Import-Package>
          </instructions>
        </configuration>
      </plugin>
    </plugins>
  </build>
  ...
</project>

Chapter 35. Facebook

Facebook Component

Available as of Camel 2.12
The Facebook component provides access to all of the Facebook APIs accessible using Facebook4J. It allows producing messages to retrieve, add, and delete posts, likes, comments, photos, albums, videos, photos, checkins, locations, links, etc. It also supports APIs that allow polling for posts, users, checkins, groups, locations, etc.
Facebook requires the use of OAuth for all client application authentication. In order to use camel-facebook with your account, you'll need to create a new application within Facebook at https://developers.facebook.com/apps and grant the application access to your account. The Facebook application's id and secret will allow access to Facebook APIs which do not require a current user. A user access token is required for APIs that require a logged in user. More information on obtaining a user access token can be found at https://developers.facebook.com/docs/facebook-login/access-tokens/.
Maven users will need to add the following dependency to their pom.xml for this component:
	<dependency>
    	<groupId>org.apache.camel</groupId>
    	<artifactId>camel-facebook</artifactId>
    	<version>${camel-version}</version>
	</dependency>

URI format

  facebook://[endpoint]?[options]

FacebookComponent

The facebook component can be configured with the Facebook account settings below, which are mandatory. The values can be provided to the component using the bean property configuration of type org.apache.camel.component.facebook.config.FacebookConfiguration. The oAuthAccessToken option may be ommited but that will only allow access to application APIs.
You can also configure these options directly in an endpoint URI.
Option Description
oAuthAppId The application Id
oAuthAppSecret The application Secret
oAuthAccessToken The user access token
In addition to the above settings, non-mandatory options below can be used to configure the underlying Facebook4J runtime through either the component's configuration property or in an endpoint URI.
Option Description Default Value
oAuthAuthorizationURL OAuth authorization URL https://www.facebook.com/dialog/oauth
oAuthPermissions Default OAuth permissions. Comma separeted permission names. See https://developers.facebook.com/docs/reference/login/#permissions for the detail null
oAuthAccessTokenURL OAuth access token URL https://graph.facebook.com/oauth/access_token
debugEnabled Enables deubg output. Effective only with the embedded logger false
gzipEnabled Use Facebook GZIP encoding true
httpConnectionTimeout Http connection timeout in milliseconds 20000
httpDefaultMaxPerRoute HTTP maximum connections per route 2
httpMaxTotalConnections HTTP maximum total connections 20
httpProxyHost HTTP proxy server host name null
httpProxyPassword HTTP proxy server password null
httpProxyPort HTTP proxy server port null
httpProxyUser HTTP proxy server user name null
httpReadTimeout Http read timeout in milliseconds 120000
httpRetryCount Number of HTTP retries 0
httpRetryIntervalSeconds HTTP retry interval in seconds 5
httpStreamingReadTimeout HTTP streaming read timeout in milliseconds 40000
jsonStoreEnabled If set to true, raw JSON forms will be stored in DataObjectFactory false
mbeanEnabled If set to true, Facebook4J mbean will be registerd false
prettyDebugEnabled prettify JSON debug output if set to true false
restBaseURL API base URL https://graph.facebook.com/
useSSL Use SSL true
videoBaseURL Video API base URL https://graph-video.facebook.com/
clientURL Facebook4J API client URL http://facebook4j.org/en/facebook4j-<ersion>xml
clientVersion Facebook4J client API version 1.1.12

Producer Endpoints:

Producer endpoints can use endpoint names and options from the table below. Endpoints can also use the short name without the get or search prefix, except checkin due to ambiguity between getCheckin and searchCheckin. Endpoint options that are not mandatory are denoted by [].
Producer endpoints can also use a special option *inBody* that in turn should contain the name of the endpoint option whose value will be contained in the Camel Exchange In message. For example, the facebook endpoint in the following route retrieves activities for the user id value in the incoming message body.
	from("direct:test").to("facebook://activities?inBody=userId")...
Any of the endpoint options can be provided in either the endpoint URI, or dynamically in a message header. The message header name must be of the format CamelFacebook.option. For example, the userId option value in the previous route could alternately be provided in the message header CamelFacebook.userId. Note that the inBody option overrides message header, e.g. the endpoint option inBody=user would override a CamelFacebook.userId header.
Endpoints that return a String return an Id for the created or modified entity, e.g. addAlbumPhoto returns the new album Id. Endpoints that return a boolean, return true for success and false otherwise. In case of Facebook API errors the endpoint will throw a RuntimeCamelException with a facebook4j.FacebookException cause.
Endpoint Short Name Options Body Type
Accounts
getAccounts accounts [reading],[userId] facebook4j.ResponseList<acebook4j.Account>
Activities
getActivities activities [reading],[userId] facebook4j.ResponseList<acebook4j.Activity>
Albums
addAlbumPhoto addAlbumPhoto albumId,source,[message] String
commentAlbum commentAlbum albumId,message String
createAlbum createAlbum albumCreate,[userId] String
getAlbum album albumId,[reading] facebook.Album
getAlbumComments albumComments albumId,[reading] facebook4j.ResponseList<acebook4j.Comment>
getAlbumCoverPhoto albumCoverPhoto albumId java.net.URL
getAlbumLikes albumLikes albumId,[reading] facebook4j.ResponseList<acebook4j.Like>
getAlbumPhotos albumPhotos albumId,[reading] facebook4j.ResponseList<acebook4j.Photos>
getAlbums albums [reading],[userId] facebook4j.ResponseList<acebook4j.Album>
likeAlbum likeAlbum albumId boolean
unlikeAlbum unlikeAlbum albumId boolean
Checkins
checkin checkin checkinCreate,[userId] String
commentCheckin commentCheckin checkinId,message String
getCheckin checkin checkinId,[reading] facebook4j.Checkin
getCheckinComments checkinComments checkinId,[reading] facebook4j.ResponseList<acebook4j.Comment>
getCheckinLikes checkinLikes checkinId,[reading] facebook4j.ResponseList<acebook4j.Like>
getCheckins checkins [reading],[userId] facebook4j.ResponseList<acebook4j.Checkin>
likeCheckin likeCheckin checkinId boolean
unlikeCheckin unlikeCheckin checkinId boolean
Comments
deleteComment deleteComment commentId boolean
getComment comment commentId facebook4j.Comment
getCommentLikes commentLikes commentId,[reading] facebook4j.ResponseList<acebook4j.Like>
likeComment likeComment commentId boolean
unlikeComment unlikeComment commentId boolean
Domains
getDomain domain domainId facebook4j.Domain
getDomainByName domainByName domainName facebook4j.Domain
getDomainsByName domainsByName domainNames java.util.List<acebook4j.Domain>
Events
createEvent createEvent eventUpdate,[userId] String
deleteEvent deleteEvent eventId boolean
deleteEventPicture deleteEventPicture eventId boolean
editEvent editEvent eventId,eventUpdate boolean
getEvent event eventId,[reading] facebook4j.Event
getEventFeed eventFeed eventId,[reading] facebook4j.ResponseList<acebook4j.Post>
getEventPhotos eventPhotos eventId,[reading] facebook4j.ResponseList<acebook4j.Photo>
getEventPictureURL eventPictureURL eventId,[size] java.net.URL
getEvents events [reading],[userId] facebook4j.ResponseList<acebook4j.Event>
getEventVideos eventVideos eventId,[reading] facebook4j.ResponseList<acebook4j.Video>
getRSVPStatusAsInvited rSVPStatusAsInvited eventId,[userId] facebook4j.ResponseList<acebook4j.RSVPStatus>
getRSVPStatusAsNoreply rSVPStatusAsNoreply eventId,[userId] facebook4j.ResponseList<acebook4j.RSVPStatus>
getRSVPStatusInAttending rSVPStatusInAttending eventId,[userId] facebook4j.ResponseList<acebook4j.RSVPStatus>
getRSVPStatusInDeclined rSVPStatusInDeclined eventId,[userId] facebook4j.ResponseList<acebook4j.RSVPStatus>
getRSVPStatusInMaybe rSVPStatusInMaybe eventId,[userId] facebook4j.ResponseList<acebook4j.RSVPStatus>
inviteToEvent inviteToEvent eventId,[userId],[userIds] boolean
postEventFeed postEventFeed eventId,postUpdate String
postEventLink postEventLink eventId,link,[message] String
postEventPhoto postEventPhoto eventId,source,[message] String
postEventStatusMessage postEventStatusMessage eventId,message String
postEventVideo postEventVideo eventId,source,[title,description] String
rsvpEventAsAttending rsvpEventAsAttending eventId boolean
rsvpEventAsDeclined rsvpEventAsDeclined eventId boolean
rsvpEventAsMaybe rsvpEventAsMaybe eventId boolean
uninviteFromEvent uninviteFromEvent eventId,userId boolean
updateEventPicture updateEventPicture eventId,source boolean
Family
getFamily family [reading],[userId] facebook4j.ResponseList<acebook4j.Family>
Favorites
getBooks books [reading],[userId] facebook4j.ResponseList<acebook4j.Book>
getGames games [reading],[userId] facebook4j.ResponseList<acebook4j.Game>
getInterests interests [reading],[userId] facebook4j.ResponseList<acebook4j.Interest>
getMovies movies [reading],[userId] facebook4j.ResponseList<acebook4j.Movie>
getMusic music [reading],[userId] facebook4j.ResponseList<acebook4j.Music>
getTelevision television [reading],[userId] facebook4j.ResponseList<acebook4j.Television>
Facebook Query Language (FQL)
executeFQL executeFQL query,[locale] facebook4j.internal.org.json.JSONArray
executeMultiFQL executeMultiFQL queries,[locale] java.util.Map<tring,facebook4j.internal.org.json.JSONArray>
Friends
addFriendlistMember addFriendlistMember friendlistId,userId boolean
createFriendlist createFriendlist friendlistName,[userId] String
deleteFriendlist deleteFriendlist friendlistId boolean
getBelongsFriend belongsFriend friendId,[reading],[userId] facebook4j.ResponseList<acebook4j.Friend>
getFriendlist friendlist friendlistId,[reading] facebook4j.FriendList
getFriendlistMembers friendlistMembers friendlistId facebook4j.ResponseList<acebook4j.Friend>
getFriendlists friendlists [reading],[userId] facebook4j.ResponseList<acebook4j.FriendList>
getFriendRequests friendRequests [reading],[userId] facebook4j.ResponseList<acebook4j.FriendRequest>
getFriends friends [reading],[userId] facebook4j.ResponseList<acebook4j.Friend>
getMutualFriends mutualFriends [friendUserId],[reading],[userId1,userId2] facebook4j.ResponseList<acebook4j.Friend>
removeFriendlistMember removeFriendlistMember friendlistId,userId boolean
Games
deleteAchievement deleteAchievement achievementURL,[userId] boolean
deleteScore deleteScore [userId] boolean
getAchievements achievements [reading],[userId] facebook4j.ResponseList<acebook4j.Achievement>
getScores scores [reading],[userId] facebook4j.ResponseList<acebook4j.Score>
postAchievement postAchievement achievementURL,[userId] String
postScore postScore scoreValue,[userId] String
Groups
getGroup group groupId,[reading] facebook4j.Group
getGroupDocs groupDocs groupId,[reading] facebook4j.ResponseList<acebook4j.GroupDoc>
getGroupFeed groupFeed groupId,[reading] facebook4j.ResponseList<acebook4j.Post>
getGroupMembers groupMembers groupId,[reading] facebook4j.ResponseList<acebook4j.GroupMember>
getGroupPictureURL groupPictureURL groupId java.net.URL
getGroups groups [reading],[userId] facebook4j.ResponseList<acebook4j.Group>
postGroupFeed postGroupFeed groupId,postUpdate String
postGroupLink postGroupLink groupId,link,[message] String
postGroupStatusMessage postGroupStatusMessage groupId,message String
Insights
getInsights insights objectId,metric,[reading] facebook4j.ResponseList<acebook4j.Insight>
Likes
getUserLikes userLikes [reading],[userId] facebook4j.ResponseList<acebook4j.Like>
Links
commentLink commentLink linkId,message String
getLink link linkId,[reading] facebook4j.Link
getLinkComments linkComments linkId,[reading] facebook4j.ResponseList<acebook4j.Comment>
getLinkLikes linkLikes linkId,[reading] facebook4j.ResponseList<acebook4j.Like>
likeLink likeLink linkId boolean
unlikeLink unlikeLink linkId boolean
Locations
getLocations locations [reading],[userId] facebook4j.ResponseList<acebook4j.Location>
Messages
getInbox inbox [reading],[userId] facebook4j.InboxResponseList<acebook4j.Inbox>
getMessage message messageId,[reading] facebook4j.Message
getOutbox outbox [reading],[userId] facebook4j.ResponseList<acebook4j.Message>
getUpdates updates [reading],[userId] facebook4j.ResponseList<acebook4j.Message>
Notes
commentNote commentNote noteId,message String
createNote createNote subject,message,[userId] String
getNote note noteId,[reading] facebook4j.Note
getNoteComments noteComments noteId,[reading] facebook4j.ResponseList<acebook4j.Comment>
getNoteLikes noteLikes noteId,[reading] facebook4j.ResponseList<acebook4j.Like>
getNotes notes [reading],[userId] facebook4j.ResponseList<acebook4j.Note>
likeNote likeNote noteId boolean
unlikeNote unlikeNote noteId boolean
Notifications
getNotifications notifications [includeRead],[reading],[userId] facebook4j.ResponseList<acebook4j.Notification>
markNotificationAsRead markNotificationAsRead notificationId boolean
Permissions
getPermissions permissions [userId] java.util.List<acebook4j.Permission>
revokePermission revokePermission permissionName,[userId] boolean
Photos
addTagToPhoto addTagToPhoto photoId,[toUserId],[toUserIds],[tagUpdate] boolean
commentPhoto commentPhoto photoId,message String
deletePhoto deletePhoto photoId boolean
getPhoto photo photoId,[reading] facebook4j.Photo
getPhotoComments photoComments photoId,[reading] facebook4j.ResponseList<acebook4j.Comment>
getPhotoLikes photoLikes photoId,[reading] facebook4j.ResponseList<acebook4j.Like>
getPhotos photos [reading],[userId] facebook4j.ResponseList<acebook4j.Photo>
getPhotoURL photoURL photoId java.net.URL
getTagsOnPhoto tagsOnPhoto photoId,[reading] facebook4j.ResponseList<acebook4j.Tag>
likePhoto likePhoto photoId boolean
postPhoto postPhoto source,[message],[place],[noStory],[userId] String
unlikePhoto unlikePhoto photoId boolean
updateTagOnPhoto updateTagOnPhoto photoId,[toUserId],[tagUpdate] boolean
Pokes
getPokes pokes [reading],[userId] facebook4j.ResponseList<acebook4j.Poke>
Posts
commentPost commentPost postId,message String
deletePost deletePost postId boolean
getFeed feed [reading],[userId] facebook4j.ResponseList<acebook4j.Post>
getHome home [reading] facebook4j.ResponseList<acebook4j.Post>
getLinks links [reading],[userId] facebook4j.ResponseList<acebook4j.Link>
getPost post postId,[reading] facebook4j.Post
getPostComments postComments postId,[reading] facebook4j.ResponseList<acebook4j.Comment>
getPostLikes postLikes postId,[reading] facebook4j.ResponseList<acebook4j.Like>
getPosts posts [reading],[userId] facebook4j.ResponseList<acebook4j.Post>
getStatuses statuses [reading],[userId] facebook4j.ResponseList<acebook4j.Post>
getTagged tagged [reading],[userId] facebook4j.ResponseList<acebook4j.Post>
likePost likePost postId boolean
postFeed postFeed postUpdate,[userId] String
postLink postLink link,[message],[userId] String
postStatusMessage postStatusMessage message,[userId] String
unlikePost unlikePost postId boolean
Questions
addQuestionOption addQuestionOption questionId,optionDescription String
createQuestion createQuestion question,[options],[allowNewOptions],[userId] String
deleteQuestion deleteQuestion questionId boolean
getQuestion question questionId,[reading] facebook4j.Question
getQuestionOptions questionOptions questionId,[reading] facebook4j.ResponseList<acebook4j.Question.Option>
getQuestionOptionVotes questionOptionVotes questionId facebook4j.ResponseList<acebook4j.QuestionVotes>
getQuestions questions [reading],[userId] facebook4j.ResponseList<acebook4j.Question>
getSubscribedto subscribedto [reading],[userId] facebook4j.ResponseList<acebook4j.Subscribedto>
getSubscribers subscribers [reading],[userId] facebook4j.ResponseList<acebook4j.Subscriber>
Test Users
createTestUser createTestUser appId,[name],[userLocale],[permissions] facebook4j.TestUser
deleteTestUser deleteTestUser testUserId boolean
getTestUsers testUsers appId java.util.List<acebook4j.TestUser>
makeFriendTestUser makeFriendTestUser testUser1,testUser2 boolean
Users
getMe me [reading] facebook4j.User
getPictureURL pictureURL [size],[userId] java.net.URL
getUser user userId,[reading] facebook4j.User
getUsers users ids java.util.List<acebook4j.User>
Videos
commentVideo commentVideo videoId,message String
getVideo video videoId,[reading] facebook4j.Video
getVideoComments videoComments videoId,[reading] facebook4j.ResponseList<acebook4j.Comment>
getVideoCover videoCover videoId java.net.URL
getVideoLikes videoLikes videoId,[reading] facebook4j.ResponseList<acebook4j.Like>
getVideos videos [reading],[userId] facebook4j.ResponseList<acebook4j.Video>
likeVideo likeVideo videoId boolean
postVideo postVideo source,[title,description],[userId] String
unlikeVideo unlikeVideo videoId boolean
Search
search search query,[reading] facebook4j.ResponseList<acebook4j.internal.org.json.JSONObject>
searchCheckins checkins [reading] facebook4j.ResponseList<acebook4j.Checkin>
searchEvents events query,[reading] facebook4j.ResponseList<acebook4j.Event>
searchGroups groups query,[reading] facebook4j.ResponseList<acebook4j.Group>
searchLocations locations [center,distance],[reading],[placeId] facebook4j.ResponseList<acebook4j.Location>
searchPlaces places query,[reading],[center,distance] facebook4j.ResponseList<acebook4j.Place>
searchPosts posts query,[reading] facebook4j.ResponseList<acebook4j.Post>
searchUsers users query,[reading] facebook4j.ResponseList<acebook4j.User>

Consumer Endpoints:

Any of the producer endpoints that take a reading#reading parameter can be used as a consumer endpoint. The polling consumer uses the since and until fields to get responses within the polling interval. In addition to other reading fields, an initial since value can be provided in the endpoint for the first poll.
Rather than the endpoints returning a List (or facebook4j.ResponseList) through a single route exchange, camel-facebook creates one route exchange per returned object. As an example, if "facebook://home" results in five posts, the route will be executed five times (once for each Post).
  1. URI Options #
Name Type Description
achievementURL java.net.URL The unique URL of the achievement
albumCreate facebook4j.AlbumCreate The facebook Album to be created
albumId String The album ID
allowNewOptions boolean True if allows other users to add new options
appId String The ID of the Facebook Application
center facebook4j.GeoLocation Location latitude and longitude
checkinCreate facebook4j.CheckinCreate The checkin to be created. Deprecated, instead create a Post with an attached location
checkinId String The checkin ID
commentId String The comment ID
description String The description text
distance int Distance in meters
domainId String The domain ID
domainName String The domain name
domainNames String[] The domain names
eventId String The event ID
eventUpdate facebook4j.EventUpdate The event to be created or updated
friendId String The friend ID
friendUserId String The friend user ID
friendlistId String The friend list ID
friendlistName String The friend list Name
groupId String The group ID
ids String[] The ids of users
includeRead boolean Enables notifications that the user has already read in addition to unread ones
link java.net.URL Link URL
linkId String The link ID
locale java.util.Locale Desired FQL locale
message String The message text
messageId String The message ID
metric String The metric name
name String Test user name, must be of the form 'first last'
noStory boolean If set to true, optionally suppresses the feed story that is automatically generated on a user's profile when they upload a photo using your application.
noteId String The note ID
notificationId String The notification ID
objectId String The insight object ID
optionDescription String The question's answer option description
options java.util.List<tring> The question's answer options
permissionName String The permission name
permissions String Test user permissions in the format perm1,perm2,...
photoId String The photo ID
place String The Facebook ID of the place associated with the Photo
placeId String The place ID
postId String The post ID
postUpdate facebook4j.PostUpdate The post to create or update
queries java.util.Map<tring> FQL queries
query String FQL query or search terms for search* endpoints
question String The question text
questionId String The question id
reading facebook4j.Reading Optional reading parameters. See Reading Options(#reading)
scoreValue int The numeric score with value
size facebook4j.PictureSize The picture size, one of large, normal, small or square
source facebook4j.Media The media content from either a java.io.File or java.io.Inputstream
subject String The note of the subject
tagUpdate facebook4j.TagUpdate Photo tag information
testUser1 facebook4j.TestUser Test user
testUser2 facebook4j.TestUser Test user
testUserId String The ID of the test user
title String The title text
toUserId String The ID of the user to tag
toUserIds java.util.List<tring> The IDs of the users to tag
userId String The Facebook user ID
userId1 String The ID of a user
userId2 String The ID of a user
userIds String[] The IDs of users to invite to event
userLocale String The test user locale
videoId String The video ID

Reading Options

The reading option of type facebook4j.Reading adds support for reading parameters, which allow selecting specific fields, limits the number of results, etc. For more information see Graph API#reading - Facebook Developers.
It is also used by consumer endpoints to poll Facebook data to avoid sending duplicate messages across polls.
The reading option can be a reference or value of type facebook4j.Reading, or can be specified using the following reading options in either the endpoint URI or exchange header with CamelFacebook. prefix.
Option Description
reading.fields Field names to retrieve, in the format field1,field2,...
reading.limit Limit for number of items to return for list results, e.g. a limit of 10 returns items 1 through 10
reading.offset Starting offset for list results, e.g. a limit of 10, and offset of 10 returns items 11 through 20
reading.until A Unix timestamp or strtotime data value that points to the end of the range of time-based data
reading.since A Unix timestamp or strtotime data value that points to the start of the range of time-based data
reading.locale Retrieve localized content in a particular locale, specified as a String with the format language[,country][,variant]
reading.with Retrieve information about objects that have location information attached, set it to true
reading.metadata Use Facebook Graph API Introspection to retrieve object metadata, set it to true
reading.filter User's stream filter key. See Facebook stream_filter

Message header

Any of the URI options#urioptions can be provided in a message header for producer endpoints with CamelFacebook. prefix.

Message body

All result message bodies utilize objects provided by the Facebook4J API. Producer endpoints can specify the option name for incoming message body in the inBody endpoint parameter.
For endpoints that return an array, or facebook4j.ResponseList, or java.util.List, a consumer endpoint will map every elements in the list to distinct messages.

Use cases

To create a post within your Facebook profile, send this producer a facebook4j.PostUpdate body.
	from("direct:foo")
		.to("facebook://postFeed/inBody=postUpdate);
To poll, every 5 sec., all statuses on your home feed:
	from("facebook://home?delay=5")
		.to("bean:blah");
Searching using a producer with dynamic options from header.
In the bar header we have the Facebook search string we want to execute in public posts, so we need to assign this value to the CamelFacebook.query header.
	from("direct:foo")
		.setHeader("CamelFacebook.query", header("bar"))
		.to("facebook://posts");

Chapter 36. File2

File Component - Apache Camel 2.0 onwards

The File component provides access to file systems, allowing files to be processed by any other Apache Camel Components or messages from other components to be saved to disk.

URI format

file:directoryName[?options]
or
file://directoryName[?options]
Where directoryName represents the underlying file directory.
You can append query options to the URI in the following format, ?option=value&option=value&...

Note

Apache Camel only supports endpoints configured with a starting directory. So the directoryName must be a directory. If you want to consume a single file only, you can use the fileName option, e.g. by setting fileName=thefilename. Also, the starting directory must not contain dynamic expressions with ${ } placeholders. Again use the fileName option to specify the dynamic part of the filename.

Avoid reading files currently being written by another application

Beware the JDK File IO API is a bit limited in detecting whether another application is currently writing/copying a file. And the implementation can be different depending on OS platform as well. This could lead to that Apache Camel thinks the file is not locked by another process and start consuming it. Therefore you have to do you own investigation as to what suits your environment. To help with this, Apache Camel provides different readLock options and the doneFileOption option that you can use. See also the section the section called “Consuming files from folders where others drop files directly”.

URI Options

Name Default Value Description
autoCreate true Automatically create missing directories in the file's pathname. For the file consumer, that means creating the starting directory. For the file producer, it means the directory where the files should be written.
bufferSize 128kb Write buffer sized in bytes.
fileName null Use Expression such as File Language to dynamically set the filename. For consumers, it's used as a filename filter. For producers, it's used to evaluate the filename to write. If an expression is set, it take precedence over the CamelFileName header. (Note: The header itself can also be an Expression). The expression options support both String and Expression types. If the expression is a String type, it is always evaluated using the File Language. If the expression is an Expression type, the specified Expression type is used - this allows you, for instance, to use OGNL expressions. For the consumer, you can use it to filter filenames, so you can for instance consume today's file using the File Language syntax: mydata-${date:now:yyyyMMdd}.txt. From Camel 2.11 onwards the producers support the CamelOverruleFileName header which takes precedence over any existing CamelFileName header; the CamelOverruleFileName is a header that is used only once, and makes it easier as this avoids to temporary store CamelFileName and have to restore it afterwards.
flatten false Flatten is used to flatten the file name path to strip any leading paths, so it's just the file name. This allows you to consume recursively into sub-directories, but when you eg write the files to another directory they will be written in a single directory. Setting this to true on the producer enforces that any file name recived in CamelFileName header will be stripped for any leading paths.
charset null Camel 2.5: this option is used to specify the encoding of the file, and camel will set the Exchange property with Exchange.CHARSET_NAME with the value of this option.
copyAndDeleteOnRenameFail true Camel 2.9: whether to fallback and do a copy and delete file, in case the file could not be renamed directly. This option is not available for the FTP component.

Consumer only

Name Default Value Description
initialDelay 1000 Milliseconds before polling the file/directory starts.
delay 500 Milliseconds before the next poll of the file/directory.
useFixedDelay true Set to true to use fixed delay between pools, otherwise fixed rate is used. See ScheduledExecutorService in JDK for details.
runLoggingLevel TRACE Camel 2.8: The consumer logs a start/complete log line when it polls. This option allows you to configure the logging level for that.
recursive false If a directory, will look for files in all the sub-directories as well.
delete false If true, the file will be deleted after it is processed
noop false If true, the file is not moved or deleted in any way. This option is good for readonly data, or for ETL type requirements. If noop=true, Apache Camel will set idempotent=true as well, to avoid consuming the same files over and over again.
preMove null Use Expression such as File Language to dynamically set the filename when moving it before processing. For example to move in-progress files into the order directory set this value to order.
move .camel Use Expression such as File Language to dynamically set the filename when moving it after processing. To move files into a .done subdirectory just enter .done.
moveFailed null Use Expression such as File Language to dynamically set the filename when moving failed files after processing. To move files into a error subdirectory just enter error. Note: When moving the files to another location it can/will handle the error when you move it to another location so Apache Camel cannot pick up the file again.
include null Is used to include files, if filename matches the regex pattern.
exclude null Is used to exclude files, if filename matches the regex pattern.
antInclude null Camel 2.10: Ant style filter inclusion, for example antInclude=\*{}*/*{}.txt. Multiple inclusions may be specified in comma-delimited format. See below for more details about ant path filters.
antExclude null Camel 2.10: Ant style filter exclusion. If both antInclude and antExclude are used, antExclude takes precedence over antInclude. Multiple exclusions may be specified in comma-delimited format. See below for more details about ant path filters.
antFilterCaseSensitive true Camel 2.11: Ant style filter which is case sensitive or not.
idempotent false Option to use the Idempotent Consumer EIP pattern to let Apache Camel skip already processed files. Will by default use a memory based LRUCache that holds 1000 entries. If noop=true then idempotent will be enabled as well to avoid consuming the same files over and over again.
idempotentKey Expression Camel 2.11: To use a custom idempotent key. By default the absolute path of the file is used. You can use the File Language, for example to use the file name and file size, you can do: idempotentKey=$-$ .
idempotentRepository null Pluggable repository as a org.apache.camel.processor.idempotent.MessageIdRepository class. Will by default use MemoryMessageIdRepository if none is specified and idempotent is true.
inProgressRepository memory Pluggable in-progress repository as a org.apache.camel.processor.idempotent.MessageIdRepository class. The in-progress repository is used to account the current in progress files being consumed. By default a memory based repository is used.
filter null Pluggable filter as a org.apache.camel.component.file.GenericFileFilter class. Will skip files if filter returns false in its accept() method. Apache Camel also ships with an ANT path matcher filter in the camel-spring component. More details in section below.
sorter null Pluggable sorter as a java.util.Comparator<org.apache.camel.component.file.GenericFile> class.
sortBy null Built-in sort using the File Language. Supports nested sorts, so you can have a sort by file name and as a 2nd group sort by modified date. See sorting section below for details.
readLock markerFile
Used by consumer, to only poll the files if it has exclusive read-lock on the file (i.e. the file is not in-progress or being written). Apache Camel will wait until the file lock is granted.
The readLock option supports the following built-in strategies:
  • changed uses a length/modification timestamp to detect whether the file is currently being copied or not. Will wait at least 1 second to determine this, so this option cannot consume files as fast as the others, but can be more reliable as the JDK IO API cannot always determine whether a file is currently being used by another process.
  • rename attempts to rename the file, in order to test whether we can get an exclusive read-lock.
  • none is for no read locks at all.
readLockTimeout 0 (for FTP, 2000) Optional timeout in milliseconds for the read-lock, if supported by the read-lock. If the read-lock could not be granted and the timeout triggered, then Apache Camel will skip the file. At next poll Apache Camel, will try the file again, and this time maybe the read-lock could be granted. Currently fileLock, changed and rename support the timeout.
readLockCheckInterval 1000 (for FTP, 5000) Camel 2.6: Interval in millis for the read-lock, if supported by the read lock. This interval is used for sleeping between attempts to acquire the read lock. For example when using the changed read lock, you can set a higher interval period to cater for slow writes. The default of 1 sec. may be too fast if the producer is very slow writing the file.
readLockMinLength 1 Camel 2.10.1: This option applied only for readLock=changed. This option allows you to configure a minimum file length. By default Camel expects the file to contain data, and thus the default value is 1. You can set this option to zero, to allow consuming zero-length files.
readLockLoggingLevel WARN Camel 2.12: Logging level used when a read lock could not be acquired. By default a WARN is logged. You can change this level, for example to OFF to not have any logging. This option is only applicable for readLock of types: changed, fileLock, rename.
exclusiveReadLockStrategy null Pluggable read-lock as a org.apache.camel.component.file.GenericFileExclusiveReadLockStrategy implementation.
minDepth 0 Camel 2.8: The minimum depth to start processing when recursively processing a directory. Using minDepth=1 means the base directory. Using minDepth=2 means the first sub directory. This option is not supported by FTP consumer.
maxDepth Integer.MAX_VALUE Camel 2.8: The maximum depth to traverse when recursively processing a directory. This option is not supported by FTP consumer.
doneFileName null Camel 2.6: If provided, Camel will only consume files if a done file exists. This option configures what file name to use. Either you can specify a fixed name. Or you can use dynamic placeholders. The done file is always expected in the same folder as the original file. See using done file and writing done file sections for examples.
processStrategy null A pluggable org.apache.camel.component.file.GenericFileProcessStrategy allowing you to implement your own readLock option or similar. Can also be used when special conditions must be met before a file can be consumed, such as a special ready file exists. If this option is set then the readLock option does not apply.
maxMessagesPerPoll 0 An integer that defines the maximum number of messages to gather per poll. By default, no maximum is set. Can be used to set a limit of e.g. 1000 to avoid having the server read thousands of files as it starts up. Set a value of 0 or negative to disabled it.
startingDirectoryMustExist false Whether the starting directory must exist. Mind that the autoCreate option is default enabled, which means the starting directory is normally auto-created if it doesn't exist. You can disable autoCreate and enable this to ensure the starting directory must exist. Will throw an exception, if the directory doesn't exist.
directoryMustExist false Similar to startingDirectoryMustExist but this applies during polling recursive sub-directories.
scheduler null Camel 2.12: To use a custom scheduler to trigger the consumer to run. See more details at Polling Consumer, for example there is a Quartz2, and Spring based scheduler that supports CRON expressions.
backoffMultiplier 0 Camel 2.12: To let the scheduled polling consumer backoff if there has been a number of subsequent idles/errors in a row. The multiplier is then the number of polls that will be skipped before the next actual attempt is happening again. When this option is in use then backoffIdleThreshold and/or backoffErrorThreshold must also be configured. See more details at Polling Consumer.
backoffIdleThreshold 0 Camel 2.12: The number of subsequent idle polls that should happen before the backoffMultipler should kick-in.
backoffErrorThreshold 0 Camel 2.12: The number of subsequent error polls (failed due some error) that should happen before the backoffMultipler should kick-in.

Default behavior for file consumer

  • By default the file is locked for the duration of the processing.
  • After the route has completed, files are moved into the .camel subdirectory, so that they appear to be deleted.
  • The File Consumer will always skip any file whose name starts with a dot, such as ., .camel, .m2 or .groovy.
  • Only files (not directories) are matched for valid filename, if options such as: includeNamePrefix, includeNamePostfix, excludeNamePrefix, excludeNamePostfix, regexPattern are used.

Producer only

Name Default Value Description
fileExist Override What to do if a file already exists with the same name. The following values can be specified: Override, Append, Fail, Ignore, Move, and TryRename (Camel 2.11.1). Override, which is the default, replaces the existing file. Append adds content to the existing file. Fail throws a GenericFileOperationException, indicating that there is already an existing file. Ignore silently ignores the problem and does not override the existing file, but assumes everything is okay. The Move option requires Camel 2.10.1 onwards, and the corresponding moveExisting option to be configured as well. The option eagerDeleteTargetFile can be used to control what to do if an moving the file, and there exists already an existing file, otherwise causing the move operation to fail. The Move option will move any existing files, before writing the target file. TryRenameCamel 2.11.1 is only applicable if tempFileName option is in use. This allows to try renaming the file from the temporary name to the actual name, without doing any exists check. This check may be faster on some file systems and especially FTP servers.
tempPrefix null This option is used to write the file using a temporary name and then, after the write is complete, rename it to the real name. Can be used to identify files being written and also avoid consumers (not using exclusive read locks) reading in progress files. Is often used by FTP when uploading big files.
tempFileName null Camel 2.1: The same as tempPrefix option but offering a more fine grained control on the naming of the temporary filename as it uses the File Language.
keepLastModified false Camel 2.2: Will keep the last modified timestamp from the source file (if any). Will use the Exchange.FILE_LAST_MODIFIED header to located the timestamp. This header can contain either a java.util.Date or long with the timestamp. If the timestamp exists and the option is enabled it will set this timestamp on the written file. Note: This option only applies to the file producer. You cannot use this option with any of the ftp producers.
eagerDeleteTargetFile true Camel 2.3: Whether or not to eagerly delete any existing target file. This option only applies when you use fileExists=Override and the tempFileName option as well. You can use this to disable (set it to false) deleting the target file before the temp file is written. For example you may write big files and want the target file to exists during the temp file is being written. This ensure the target file is only deleted until the very last moment, just before the temp file is being renamed to the target filename.
doneFileName null Camel 2.6: If provided, then Camel will write a 2nd done file when the original file has been written. The done file will be empty. This option configures what file name to use. Either you can specify a fixed name. Or you can use dynamic placeholders. The done file will always be written in the same folder as the original file. See writing done file section for examples.
allowNullBody false Camel 2.10.1: Used to specify if a null body is allowed during file writing. If set to true then an empty file will be created, when set to false, and attempting to send a null body to the file component, a GenericFileWriteException of 'Cannot write null body to file.' will be thrown. If the `fileExist` option is set to 'Override', then the file will be truncated, and if set to `append` the file will remain unchanged.
forceWrites true Camel 2.10.5/2.11: Whether to force syncing writes to the file system. You can turn this off if you do not want this level of guarantee, for example if writing to logs / audit logs etc; this would yield better performance.

Default behavior for file producer

  • By default it will override any existing file, if one exist with the same name. In Apache Camel 1.x the Append is the default for the file producer. We have changed this to Override in Apache Camel 2.0 as this is also the default file operation using java.io.File. And also the default for the FTP library we use in the camel-ftp component.

Move and Delete operations

Any move or delete operations is executed after (post command) the routing has completed; so during processing of the Exchange the file is still located in the inbox folder.
Lets illustrate this with an example:
    from("file://inbox?move=.done").to("bean:handleOrder");
When a file is dropped in the inbox folder, the file consumer notices this and creates a new FileExchange that is routed to the handleOrder bean. The bean then processes the File object. At this point in time the file is still located in the inbox folder. After the bean completes, and thus the route is completed, the file consumer will perform the move operation and move the file to the .done sub-folder.
The move and preMove options is considered as a directory name (though if you use an expression such as File Language, or Simple then the result of the expression evaluation is the file name to be used - eg if you set
move=../backup/copy-of-${file:name}
then that's using the File Language which we use return the file name to be used), which can be either relative or absolute. If relative, the directory is created as a sub-folder from within the folder where the file was consumed.
By default, Apache Camel will move consumed files to the .camel sub-folder relative to the directory where the file was consumed.
If you want to delete the file after processing, the route should be:
    from("file://inobox?delete=true").to("bean:handleOrder");
We have introduced a pre move operation to move files before they are processed. This allows you to mark which files have been scanned as they are moved to this sub folder before being processed.
    from("file://inbox?preMove=inprogress").to("bean:handleOrder");
You can combine the pre move and the regular move:
    from("file://inbox?preMove=inprogress&move=.done").to("bean:handleOrder");
So in this situation, the file is in the inprogress folder when being processed and after it's processed, it's moved to the .done folder.

Fine grained control over Move and PreMove option

The move and preMove option is Expression-based, so we have the full power of the File Language to do advanced configuration of the directory and name pattern. Apache Camel will, in fact, internally convert the directory name you enter into a File Language expression. So when we enter move=.done Apache Camel will convert this into: ${file:parent}/.done/${file:onlyname}. This is only done if Apache Camel detects that you have not provided a ${ } in the option value yourself. So when you enter an expression containing ${ }, the expression is interpreted as a File Language expression.
So if we want to move the file into a backup folder with today's date as the pattern, we can do:
move=backup/${date:now:yyyyMMdd}/${file:name}

About moveFailed

The moveFailed option allows you to move files that could not be processed succesfully to another location such as a error folder of your choice. For example to move the files in an error folder with a timestamp you can use moveFailed=/error/${file:name.noext}-${date:now:yyyyMMddHHmmssSSS}.${file:name.ext}.
See more examples at File Language.

Message Headers

The following headers are supported by this component:

File producer only

Header Description
CamelFileName Specifies the name of the file to write (relative to the endpoint directory). The name can be a String; a String with a File Language or Simple expression; or an Expression object. If it's null then Apache Camel will auto-generate a filename based on the message unique ID.
CamelFileNameProduced The actual absolute filepath (path + name) for the output file that was written. This header is set by Camel and its purpose is providing end-users with the name of the file that was written.
CamelOverruleFileName Camel 2.11: Is used for overruling CamelFileName header and use the value instead (but only once, as the producer will remove this header after writing the file). The value can be only be a String. Notice that if the option fileName has been configured, then this is still being evaluated.

File consumer only

Header Description
CamelFileName Name of the consumed file as a relative file path with offset from the starting directory configured on the endpoint.
CamelFileNameOnly Only the file name (the name with no leading paths).
CamelFileAbsolute A boolean option specifying whether the consumed file denotes an absolute path or not. Should normally be false for relative paths. Absolute paths should normally not be used but we added to the move option to allow moving files to absolute paths. But can be used elsewhere as well.
CamelFileAbsolutePath The absolute path to the file. For relative files this path holds the relative path instead.
CamelFilePath The file path. For relative files this is the starting directory + the relative filename. For absolute files this is the absolute path.
CamelFileRelativePath The relative path.
CamelFileParent The parent path.
CamelFileLength A long value containing the file size.
CamelFileLastModified A Date value containing the last modified timestamp of the file.

Batch Consumer

This component implements the Batch Consumer.

Exchange Properties, file consumer only

As the file consumer is BatchConsumer it supports batching the files it polls. By batching it means that Apache Camel will add some properties to the Exchange so you know the number of files polled the current index in that order.
Property Description
CamelBatchSize The total number of files that was polled in this batch.
CamelBatchIndex The current index of the batch. Starts from 0.
CamelBatchComplete A boolean value indicating the last Exchange in the batch. Is only true for the last entry.
This allows you for instance to know how many files exists in this batch and for instance let the Aggregator aggregate this number of files.

Common gotchas with folder and filenames

When Apache Camel is producing files (writing files) there are a few gotchas affecting how to set a filename of your choice. By default, Apache Camel will use the message ID as the filename, and since the message ID is normally a unique generated ID, you will end up with filenames such as: ID-MACHINENAME-2443-1211718892437-1-0. If such a filename is not desired, then you must provide a filename in the CamelFileName message header. The constant, Exchange.FILE_NAME, can also be used.
The sample code below produces files using the message ID as the filename:
from("direct:report").to("file:target/reports");
To use report.txt as the filename you have to do:
from("direct:report").setHeader(Exchange.FILE_NAME, constant("report.txt")).to( "file:target/reports");
Or the same as above, but with CamelFileName:
from("direct:report").setHeader("CamelFileName", constant("report.txt")).to( "file:target/reports");
And a syntax where we set the filename on the endpoint with the fileName URI option.
from("direct:report").to("file:target/reports/?fileName=report.txt");

Filename Expression

Filename can be set either using the expression option or as a string-based File Language expression in the CamelFileName header. See the File Language for syntax and samples.

Consuming files from folders where others drop files directly

Beware if you consume files from a folder where other applications write files directly. Take a look at the different readLock options to see what suits your use cases. The best approach is however to write to another folder and after the write move the file in the drop folder. However if you write files directly to the drop folder then the option changed could better detect whether a file is currently being written/copied as it uses a file changed algorithm to see whether the file size / modification changes over a period of time. The other read lock options rely on Java File API that sadly is not always very good at detecting this. You may also want to look at the doneFileName option, which uses a marker file (done) to signal when a file is done and ready to be consumed.

Using done files

Available as of Camel 2.6
See also section writing done files below.
If you want only to consume files when a done file exists, then you can use the doneFileName option on the endpoint.
      from("file:bar?doneFileName=done");

Will only consume files from the bar folder, if a file name done exists in the same directory as the target files. Camel will automatically delete the done file when it's done consuming the files.
However its more common to have one done file per target file. This means there is a 1:1 correlation. To do this you must use dynamic placeholders in the doneFileName option. Currently Camel supports the following two dynamic tokens: file:name and file:name.noext which must be enclosed in ${ }. The consumer only supports the static part of the done file name as either prefix or suffix (not both).
      from("file:bar?doneFileName=${file:name}.done");

In this example only files will be polled if there exists a done file with the name file name.done. For example
  • hello.txt - is the file to be consumed
  • hello.txt.done - is the associated done file
You can also use a prefix for the done file, such as:
      from("file:bar?doneFileName=ready-${file:name}");

  • hello.txt - is the file to be consumed
  • ready-hello.txt - is the associated done file

Writing done files

Available as of Camel 2.6
After you have written af file you may want to write an additional done file as a kinda of marker, to indicate to others that the file is finished and has been written. To do that you can use the doneFileName option on the file producer endpoint.
.to("file:bar?doneFileName=done");
Will simply create a file named done in the same directory as the target file.
However its more common to have one done file per target file. This means there is a 1:1 correlation. To do this you must use dynamic placeholders in the doneFileName option. Currently Camel supports the following two dynamic tokens: file:name and file:name.noext which must be enclosed in ${ }.
.to("file:bar?doneFileName=done-${file:name}");
Will for example create a file named done-foo.txt if the target file was foo.txt in the same directory as the target file.
.to("file:bar?doneFileName=${file:name}.done");
Will for example create a file named foo.txt.done if the target file was foo.txt in the same directory as the target file.
.to("file:bar?doneFileName=${file:name.noext}.done");
Will for example create a file named foo.done if the target file was foo.txt in the same directory as the target file.

Read from a directory and write to another directory

from("file://inputdir/?delete=true").to("file://outputdir")

Read from a directory and write to another directory using a overrule dynamic name

from("file://inputdir/?delete=true").to("file://outputdir?overruleFile=copy-of-${file:name}")
Listen on a directory and create a message for each file dropped there. Copy the contents to the outputdir and delete the file in the inputdir.

Reading recursively from a directory and writing to another

from("file://inputdir/?recursive=true&delete=true").to("file://outputdir")
Listen on a directory and create a message for each file dropped there. Copy the contents to the outputdir and delete the file in the inputdir. Will scan recursively into sub-directories. Will lay out the files in the same directory structure in the outputdir as the inputdir, including any sub-directories.
inputdir/foo.txt
inputdir/sub/bar.txt
Will result in the following output layout:
outputdir/foo.txt
outputdir/sub/bar.txt

Using flatten

If you want to store the files in the outputdir directory in the same directory, disregarding the source directory layout (e.g. to flatten out the path), you just add the flatten=true option on the file producer side:
from("file://inputdir/?recursive=true&delete=true").to("file://outputdir?flatten=true")
Will result in the following output layout:
outputdir/foo.txt
outputdir/bar.txt

Reading from a directory and the default move operation

Apache Camel will by default move any processed file into a .camel subdirectory in the directory the file was consumed from.
from("file://inputdir/?recursive=true&delete=true").to("file://outputdir")
Affects the layout as follows: before
inputdir/foo.txt
inputdir/sub/bar.txt
after
inputdir/.camel/foo.txt
inputdir/sub/.camel/bar.txt
outputdir/foo.txt
outputdir/sub/bar.txt

Read from a directory and process the message in java

from("file://inputdir/").process(new Processor() {
  public void process(Exchange exchange) throws Exception {
    Object body = exchange.getIn().getBody();
    // do some business logic with the input body
  }
});
The body will be a File object that points to the file that was just dropped into the inputdir directory.

Read files from a directory and send the content to a jms queue

from("file://inputdir/").convertBodyTo(String.class).to("jms:test.queue")
By default the file endpoint sends a FileMessage which contains a File object as the body. If you send this directly to the JMS component the JMS message will only contain the File object but not the content. By converting the File to a String, the message will contain the file contents, which is probably what you want.
The route above using Spring DSL:
   <route>
      <from uri="file://inputdir/"/>
      <convertBodyTo type="java.lang.String"/>
      <to uri="jms:test.queue"/>
   </route>

Writing to files

Apache Camel is of course also able to write files, i.e. produce files. In the sample below we receive some reports on the SEDA queue that we process before they are written to a directory.
public void testToFile() throws Exception {
    MockEndpoint mock = getMockEndpoint("mock:result");
    mock.expectedMessageCount(1);
    mock.expectedFileExists("target/test-reports/report.txt");

    template.sendBody("direct:reports", "This is a great report");

    assertMockEndpointsSatisfied();
}

protected JndiRegistry createRegistry() throws Exception {
    // bind our processor in the registry with the given id
    JndiRegistry reg = super.createRegistry();
    reg.bind("processReport", new ProcessReport());
    return reg;
}

protected RouteBuilder createRouteBuilder() throws Exception {
    return new RouteBuilder() {
        public void configure() throws Exception {
            // the reports from the seda queue is processed by our processor
            // before they are written to files in the target/reports directory
            from("direct:reports").processRef("processReport").to("file://target/test-reports", "mock:result");
        }
    };
}

private static class ProcessReport implements Processor {

    public void process(Exchange exchange) throws Exception {
        String body = exchange.getIn().getBody(String.class);
        // do some business logic here

        // set the output to the file
        exchange.getOut().setBody(body);

        // set the output filename using java code logic, notice that this is done by setting
        // a special header property of the out exchange
        exchange.getOut().setHeader(Exchange.FILE_NAME, "report.txt");
    }

}

Write to subdirectory using Exchange.FILE_NAME

Using a single route, it is possible to write a file to any number of subdirectories. If you have a route setup as such:
  <route>
    <from uri="bean:myBean"/>
    <to uri="file:/rootDirectory"/>
  </route>
You can have myBean set the header Exchange.FILE_NAME to values such as:
Exchange.FILE_NAME = hello.txt => /rootDirectory/hello.txt
Exchange.FILE_NAME = foo/bye.txt => /rootDirectory/foo/bye.txt
This allows you to have a single route to write files to multiple destinations.

Using expression for filenames

In this sample we want to move consumed files to a backup folder using today's date as a sub-folder name:
from("file://inbox?move=backup/${date:now:yyyyMMdd}/${file:name}").to("...");
See File Language for more samples.

Avoiding reading the same file more than once (idempotent consumer)

Apache Camel supports Idempotent Consumer directly within the component so it will skip already processed files. This feature can be enabled by setting the idempotent=true option.
from("file://inbox?idempotent=true").to("...");
Camel uses the absolute file name as the idempotent key, to detect duplicate files. From Camel 2.11 onwards you can customize this key by using an expression in the idempotentKey option. For example to use both the name and the file size as the key
  <route>
    <from uri="file://inbox?idempotent=true&dempotentKey=${file:name}-${file-size}"/>
    <to uri="bean:processInbox"/>
  </route>
By default Apache Camel uses an in-memory based store for keeping track of consumed files, it uses a least recently used cache holding up to 1000 entries. You can plugin your own implementation of this store by using the idempotentRepository option using the # sign in the value to indicate it's a referring to a bean in the Registry with the specified id.
   <!-- define our store as a plain spring bean -->
   <bean id="myStore" class="com.mycompany.MyIdempotentStore"/>

  <route>
    <from uri="file://inbox?idempotent=true&dempotentRepository=#myStore"/>
    <to uri="bean:processInbox"/>
  </route>
Apache Camel will log at DEBUG level if it skips a file because it has been consumed before:
DEBUG FileConsumer is idempotent and the file has been consumed before. Will skip this file: target\idempotent\report.txt

Using a file based idempotent repository

In this section we will use the file based idempotent repository org.apache.camel.processor.idempotent.FileIdempotentRepository instead of the in-memory based that is used as default. This repository uses a 1st level cache to avoid reading the file repository. It will only use the file repository to store the content of the 1st level cache. Thereby the repository can survive server restarts. It will load the content of the file into the 1st level cache upon startup. The file structure is very simple as it stores the key in separate lines in the file. By default, the file store has a size limit of 1mb and when the file grows larger, Apache Camel will truncate the file store and rebuild the content by flushing the 1st level cache into a fresh empty file.
We configure our repository using Spring XML creating our file idempotent repository and define our file consumer to use our repository with the idempotentRepository using \# sign to indicate Registry lookup:
<!-- this is our file based idempotent store configured to use the .filestore.dat as file -->
<bean id="fileStore" class="org.apache.camel.processor.idempotent.FileIdempotentRepository">
    <!-- the filename for the store -->
    <property name="fileStore" value="target/fileidempotent/.filestore.dat"/>
    <!-- the max filesize in bytes for the file. Apache Camel will trunk and flush the cache
         if the file gets bigger -->
    <property name="maxFileStoreSize" value="512000"/>
    <!-- the number of elements in our store -->
    <property name="cacheSize" value="250"/>
</bean>

<camelContext xmlns="http://camel.apache.org/schema/spring">
    <route>
        <from uri="file://target/fileidempotent/?idempotent=true&dempotentRepository=#fileStore&ove=done/${file:name}"/>
        <to uri="mock:result"/>
    </route>
</camelContext>

Using a JPA based idempotent repository

In this section we will use the JPA based idempotent repository instead of the in-memory based that is used as default.
First we need a persistence-unit in META-INF/persistence.xml where we need to use the class org.apache.camel.processor.idempotent.jpa.MessageProcessed as model.
<persistence-unit name="idempotentDb" transaction-type="RESOURCE_LOCAL">
  <class>org.apache.camel.processor.idempotent.jpa.MessageProcessed</class>

  <properties>
    <property name="openjpa.ConnectionURL" value="jdbc:derby:target/idempotentTest;create=true"/>
    <property name="openjpa.ConnectionDriverName" value="org.apache.derby.jdbc.EmbeddedDriver"/>
    <property name="openjpa.jdbc.SynchronizeMappings" value="buildSchema"/>
    <property name="openjpa.Log" value="DefaultLevel=WARN, Tool=INFO"/>
  </properties>
</persistence-unit>
Then we need to setup a Spring jpaTemplate in the spring XML file:
<!-- this is standard spring JPA configuration -->
<bean id="jpaTemplate" class="org.springframework.orm.jpa.JpaTemplate">
    <property name="entityManagerFactory" ref="entityManagerFactory"/>
</bean>

<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalEntityManagerFactoryBean">
    <!-- we use idempotentDB as the persitence unit name defined in the persistence.xml file -->
    <property name="persistenceUnitName" value="idempotentDb"/>
</bean>
And finally we can create our JPA idempotent repository in the spring XML file as well:
<!-- we define our jpa based idempotent repository we want to use in the file consumer -->
<bean id="jpaStore" class="org.apache.camel.processor.idempotent.jpa.JpaMessageIdRepository">
    <!-- Here we refer to the spring jpaTemplate -->
    <constructor-arg index="0" ref="jpaTemplate"/>
    <!-- This 2nd parameter is the name  (= a cateogry name).
         You can have different repositories with different names -->
    <constructor-arg index="1" value="FileConsumer"/>
</bean>
And then we just need to reference the jpaStore bean in the file consumer endpoint, using the idempotentRepository option and the # syntax:
  <route>
    <from uri="file://inbox?idempotent=true&dempotentRepository=#jpaStore"/>
    <to uri="bean:processInbox"/>
  </route>

Filter using org.apache.camel.component.file.GenericFileFilter

Apache Camel supports pluggable filtering strategies. You can then configure the endpoint with such a filter to skip certain files being processed.
In the sample we have built our own filter that skips files starting with skip in the filename:
public class MyFileFilter implements GenericFileFilter {
    public boolean accept(GenericFile pathname) {
        // we dont accept any files starting with skip in the name
        return !pathname.getFileName().startsWith("skip");
    }
}
And then we can configure our route using the filter attribute to reference our filter (using # notation) that we have defined in the spring XML file:
   <!-- define our sorter as a plain spring bean -->
   <bean id="myFilter" class="com.mycompany.MyFileSorter"/>

  <route>
    <from uri="file://inbox?filter=#myFilter"/>
    <to uri="bean:processInbox"/>
  </route>

Filtering using ANT path matcher

The ANT path matcher is shipped out-of-the-box in the camel-spring jar. So you need to depend on camel-spring if you are using Maven. The reasons is that we leverage Spring's AntPathMatcher to do the actual matching.
The file paths is matched with the following rules:
  • ? matches one character
  • * matches zero or more characters
  • ** matches zero or more directories in a path
The sample below demonstrates how to use it:
<camelContext xmlns="http://camel.apache.org/schema/spring">
    <template id="camelTemplate"/>

    <!-- use myFilter as filter to allow setting ANT paths for which files to scan for -->
    <endpoint id="myFileEndpoint" uri="file://target/antpathmatcher?recursive=true&ilter=#myAntFilter"/>

    <route>
        <from ref="myFileEndpoint"/>
        <to uri="mock:result"/>
    </route>
</camelContext>

<!-- we use the antpath file filter to use ant paths for includes and exlucde -->
<bean id="myAntFilter" class="org.apache.camel.component.file.AntPathMatcherGenericFileFilter">
    <!-- include and file in the subfolder that has day in the name -->
    <property name="includes" value="**/subfolder/**/*day*"/>
    <!-- exclude all files with bad in name or .xml files. Use comma to seperate multiple excludes -->
    <property name="excludes" value="**/*bad*,**/*.xml"/>
</bean>

Sorting using Comparator

Apache Camel supports pluggable sorting strategies. This strategy it to use the build in java.util.Comparator in Java. You can then configure the endpoint with such a comparator and have Apache Camel sort the files before being processed.
In the sample we have built our own comparator that just sorts by file name:
public class MyFileSorter implements Comparator<GenericFile> {
    public int compare(GenericFile o1, GenericFile o2) {
        return o1.getFileName().compareToIgnoreCase(o2.getFileName());
    }
}
And then we can configure our route using the sorter option to reference to our sorter (mySorter) we have defined in the spring XML file:
   <!-- define our sorter as a plain spring bean -->
   <bean id="mySorter" class="com.mycompany.MyFileSorter"/>

  <route>
    <from uri="file://inbox?sorter=#mySorter"/>
    <to uri="bean:processInbox"/>
  </route>

URI options can reference beans using the # syntax

In the Spring DSL route about notice that we can reference beans in the Registry by prefixing the id with #. So writing sorter=#mySorter, will instruct Apache Camel to go look in the Registry for a bean with the ID, mySorter.

Sorting using sortBy

Apache Camel supports pluggable sorting strategies. This strategy it to use the File Language to configure the sorting. The sortBy option is configured as follows:
sortBy=group 1;group 2;group 3;...
Where each group is separated with semi colon. In the simple situations you just use one group, so a simple example could be:
sortBy=file:name
This will sort by file name, you can reverse the order by prefixing reverse: to the group, so the sorting is now Z..A:
sortBy=reverse:file:name
As we have the full power of File Language we can use some of the other parameters, so if we want to sort by file size we do:
sortBy=file:length
You can configure to ignore the case, using ignoreCase: for string comparison, so if you want to use file name sorting but to ignore the case then we do:
sortBy=ignoreCase:file:name
You can combine ignore case and reverse, however reverse must be specified first:
sortBy=reverse:ignoreCase:file:name
In the sample below we want to sort by last modified file, so we do:
sortBy=file:modifed
And then we want to group by name as a 2nd option so files with same modifcation is sorted by name:
sortBy=file:modifed;file:name
Now there is an issue here, can you spot it? Well the modified timestamp of the file is too fine as it will be in milliseconds, but what if we want to sort by date only and then subgroup by name? Well as we have the true power of File Language we can use the its date command that supports patterns. So this can be solved as:
sortBy=date:file:yyyyMMdd;file:name
Yeah, that is pretty powerful, oh by the way you can also use reverse per group, so we could reverse the file names:
sortBy=date:file:yyyyMMdd;reverse:file:name

Using GenericFileProcessStrategy

The option processStrategy can be used to use a custom GenericFileProcessStrategy that allows you to implement your own begin, commit and rollback logic. For instance lets assume a system writes a file in a folder you should consume. But you should not start consuming the file before another ready file have been written as well.
So by implementing our own GenericFileProcessStrategy we can implement this as:
  • In the begin() method we can test whether the special ready file exists. The begin method returns a boolean to indicate if we can consume the file or not.
  • in the commit() method we can move the actual file and also delete the ready file.

Important when using consumer.bridgeErrorHandler

When using consumer.bridgeErrorHandler, then interceptors, OnCompletions does not apply. The Exchange is processed directly by the Camel error handler, and does not allow prior actions such as interceptors, onCompletion to take action.

Debug logging

This component has log level TRACE that can be helpful if you have problems.
See also:

Chapter 37. Flatpack

Flatpack Component

The Flatpack component supports fixed width and delimited file parsing using the FlatPack library. Notice: This component only supports consuming from flatpack files to Object model. You can not (yet) write from Object model to flatpack format.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-flatpack</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

flatpack:[delim|fixed]:flatPackConfig.pzmap.xml[?options]
Or for a delimited file handler with no configuration file just use:
flatpack:someName[?options]
You can append query options to the URI in the following format, ?option=value&option=value&...

URI Options

Name Default Value Description
delimiter , The default character delimiter for delimited files.
textQualifier " The text qualifier for delimited files.
ignoreFirstRecord true Whether the first line is ignored for delimited files (for the column headers).
splitRows true As of Apache Camel 1.5, the component can either process each row one by one or the entire content at once.
allowShortLines false *Camel 2.9.3:* Allows for lines to be shorter than expected and ignores the extra characters.
ignoreExtraColumns false *Camel 2.9.3:* Allows for lines to be longer than expected and ignores the extra characters.

Examples

  • flatpack:fixed:foo.pzmap.xml creates a fixed-width endpoint using the foo.pzmap.xml file configuration.
  • flatpack:delim:bar.pzmap.xml creates a delimited endpoint using the bar.pzmap.xml file configuration.
  • flatpack:foo creates a delimited endpoint called foo with no file configuration.

Message Headers

Apache Camel will store the following headers on the IN message:
Header Description
camelFlatpackCounter The current row index. For splitRows=false the counter is the total number of rows.

Message Body

The component delivers the data in the IN message as a org.apache.camel.component.flatpack.DataSetList object that has converters for java.util.Map or java.util.List. Usually you want the Map if you process one row at a time (splitRows=true). Use List for the entire content (splitRows=false), where each element in the list is a Map. Each Map contains the key for the column name and its corresponding value.
For example to get the firstname from the sample below:
  Map row = exchange.getIn().getBody(Map.class);
  String firstName = row.get("FIRSTNAME");
However, you can also always get it as a List (even for splitRows=true). The same example:
  List data = exchange.getIn().getBody(List.class);
  Map row = (Map)data.get(0);
  String firstName = row.get("FIRSTNAME");

Header and Trailer records

The header and trailer notions in Flatpack are supported. However, you must use fixed record IDs:
  • header for the header record (must be lowercase)
  • trailer for the trailer record (must be lowercase)
The example below illustrates this fact that we have a header and a trailer. You can omit one or both of them if not needed.
    <RECORD id="header" startPosition="1" endPosition="3" indicator="HBT">
        <COLUMN name="INDICATOR" length="3"/>
        <COLUMN name="DATE" length="8"/>
    </RECORD>

    <COLUMN name="FIRSTNAME" length="35" />
    <COLUMN name="LASTNAME" length="35" />
    <COLUMN name="ADDRESS" length="100" />
    <COLUMN name="CITY" length="100" />
    <COLUMN name="STATE" length="2" />
    <COLUMN name="ZIP" length="5" />

    <RECORD id="trailer" startPosition="1" endPosition="3" indicator="FBT">
        <COLUMN name="INDICATOR" length="3"/>
        <COLUMN name="STATUS" length="7"/>
    </RECORD>

Using the endpoint

A common use case is sending a file to this endpoint for further processing in a separate route. For example:
  <camelContext xmlns="http://activemq.apache.org/camel/schema/spring">
    <route>
      <from uri="file://someDirectory"/>
      <to uri="flatpack:foo"/>
    </route>

    <route>
      <from uri="flatpack:foo"/>
      ...
    </route>
  </camelContext>
You can also convert the payload of each message created to a Map for easy Bean Integration

Chapter 38. FOP

FOP Component

Available as of Camel 2.10
The FOP component allows you to render a message into different output formats using Apache FOP.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-fop</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

fop://outputFormat?[options]

Output Formats

The primary output format is PDF but other output formats are also supported:
Name Output Format Description
PDF application/pdf Portable Document Format
PS application/postscript Adobe Postscript
PCL application/x-pcl Printer Control Language
PNG image/png PNG images
JPEG image/jpeg JPEG images
SVG image/svg+xml Scalable Vector Graphics
XML application/X-fop-areatree Area tree representation
MIF application/mif FrameMaker's MIF
RTF application/rtf Rich Text Format
TXT text/plain Text
The complete list of valid output formats can be found here

Endpoint Options

name default value description
userConfigURL none The location of a configuration file with the following structure. From Camel 2.12 onwards the file is loaded from the classpath by default. You can use file:, or classpath: as prefix to load the resource from file or classpath. In previous releases the file is always loaded from file system.

Message Operations

name default value description
CamelFop.Output.Format Overrides the output format for that message
CamelFop.Encrypt.userPassword PDF user password
CamelFop.Encrypt.ownerPassword PDF owner passoword
CamelFop.Encrypt.allowPrint true Allows printing the PDF
CamelFop.Encrypt.allowCopyContent true Allows copying content of the PDF
CamelFop.Encrypt.allowEditContent true Allows editing content of the PDF
CamelFop.Encrypt.allowEditAnnotations true Allows editing annotation of the PDF
CamelFop.Render.producer Apache FOP Metadata element for the system/software that produces the document
CamelFop.Render.creator Metadata element for the user that created the document
CamelFop.Render.creationDate Creation Date
CamelFop.Render.author Author of the content of the document
CamelFop.Render.title Title of the document
CamelFop.Render.subject Subject of the document
CamelFop.Render.keywords Set of keywords applicable to this document

Example

Below is an example route that renders PDFs from XML data and XSLT template and saves the PDF files in target folder:
from("file:source/data/xml")
    .to("xslt:xslt/template.xsl")
    .to("fop:application/pdf")
    .to("file:target/data");

Chapter 39. FreeMarker

FreeMarker

The freemarker: component allows you to process a message using a FreeMarker template. This can be ideal when using Templating to generate responses for requests.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-freemarker</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

freemarker:templateName[?options]
Where templateName is the classpath-local URI of the template to invoke; or the complete URL of the remote template (for example, file://folder/myfile.ftl).
You can append query options to the URI in the following format, ?option=value&option=value&...

Options

Option Default Description
contentCache true Cache for the resource content when it's loaded. Note: as of Camel 2.9 cached resource content can be cleared via JMX using the endpoint's clearContentCache operation.
encoding null Character encoding of the resource content.
templateUpdateDelay 5 *Camel 2.9:* Number of seconds the loaded template resource will remain in the cache.

FreeMarker Context

Apache Camel will provide exchange information in the FreeMarker context (just a Map). The Exchange is transferred as:
Key Value
exchange The Exchange itself.
exchange.properties The Exchange properties.
headers The headers of the In message.
camelContext The Camel Context.
request The In message.
body The In message body.
response The Out message (only for InOut message exchange pattern).

Hot reloading

The FreeMarker template resource is by default not hot reloadable for both file and classpath resources (expanded jar). If you set contentCache=false, then Apache Camel will not cache the resource and hot reloading is thus enabled. This scenario can be used in development.

Dynamic templates

Available as of Camel 2.1 Camel provides two headers by which you can define a different resource location for a template or the template content itself. If any of these headers is set then Camel uses this over the endpoint configured resource. This allows you to provide a dynamic template at runtime.
Header Type Description Support Version
FreemarkerConstants.FREEMARKER_RESOURCE org.springframework.core.io.Resource The template resource <= 1.6.2, <= 2.1
FreemarkerConstants.FREEMARKER_RESOURCE_URI String A URI for the template resource to use instead of the endpoint configured. >= 2.1
FreemarkerConstants.FREEMARKER_TEMPLATE String The template to use instead of the endpoint configured. >= 2.1

Samples

For example, you can define a route like the following:
from("activemq:My.Queue").
  to("freemarker:com/acme/MyResponse.ftl");
To use a FreeMarker template to formulate a response to InOut message exchanges (where there is a JMSReplyTo header).
If you want to process InOnly exchanges, you could use a FreeMarker template to transform the message before sending it on to another endpoint:
from("activemq:My.Queue").
  to(ExchangePattern.InOut,"freemarker:com/acme/MyResponse.ftl").
  to("activemq:Another.Queue");
And to disable the content cache (for example, for development usage where the .ftl template should be hot reloaded):
from("activemq:My.Queue").
  to(ExchangePattern.InOut,"freemarker:com/acme/MyResponse.ftl?contentCache=false").
  to("activemq:Another.Queue");
And for a file-based resource:
from("activemq:My.Queue").
  to(ExchangePattern.InOut,"freemarker:file://myfolder/MyResponse.ftl?contentCache=false").
  to("activemq:Another.Queue");
In Camel 2.1 it's possible to specify what template the component should use dynamically via a header, so for example:
from("direct:in").
  setHeader(FreemarkerConstants.FREEMARKER_RESOURCE_URI).constant("path/to/my/template.ftl").
  to("freemarker:dummy");

The Email Sample

In this sample we want to use FreeMarker templating for an order confirmation email. The email template is laid out in FreeMarker as:
Dear ${headers.lastName}, ${headers.firstName}

Thanks for the order of ${headers.item}.

Regards Camel Riders Bookstore
${body}
And the java code:
private Exchange createLetter() {
    Exchange exchange = context.getEndpoint("direct:a").createExchange();
    Message msg = exchange.getIn();
    msg.setHeader("firstName", "Claus");
    msg.setHeader("lastName", "Ibsen");
    msg.setHeader("item", "Camel in Action");
    msg.setBody("PS: Next beer is on me, James");
    return exchange;
}

@Test
public void testFreemarkerLetter() throws Exception {
    MockEndpoint mock = getMockEndpoint("mock:result");
    mock.expectedMessageCount(1);
    mock.expectedBodiesReceived("Dear Ibsen, Claus\n\nThanks for the order of Camel in Action."
      + "\n\nRegards Camel Riders Bookstore\nPS: Next beer is on me, James");

    template.send("direct:a", createLetter());

    mock.assertIsSatisfied();
}

protected RouteBuilder createRouteBuilder() throws Exception {
    return new RouteBuilder() {
        public void configure() throws Exception {
            from("direct:a")
                .to("freemarker:org/apache/camel/component/freemarker/letter.ftl")
                .to("mock:result");
        }
    };
}

Chapter 40. FTP2

FTP/SFTP Component

This component provides access to remote file systems over the FTP and SFTP protocols.

Consuming from remote FTP server

Make sure you read the section titled Default when consuming files further below for details related to consuming files.

URI format

ftp://[username@]hostname[:port]/directoryname[?options]
sftp://[username@]hostname[:port]/directoryname[?options]
ftps://[username@]hostname[:port]/directoryname[?options]
Where directoryname represents the underlying directory. Can contain nested folders.
If no username is provided, then anonymous login is attempted using no password. If no port number is provided, Apache Camel will provide default values according to the protocol (ftp = 21, sftp = 22, ftps = 21).
This component uses two different libraries for the actual FTP work. FTP and FTPS use Apache Commons Net while SFTP uses JCraft JSCH.
You can append query options to the URI in the following format, ?option=value&option=value&...

URI Options

The options below are exclusive to the FTP component:
Name Default Value Description
username null Specifies the username to use to log in to the remote file systen.
password null Specifies the password to use to log in to the remote file system.
binary false Specifies the file transfer mode, BINARY or ASCII. Default is ASCII (false).
disconnect false Camel 2.2: Whether or not to disconnect from remote FTP server right after use. Can be used for both consumer and producer. Disconnect will only disconnect the current connection to the FTP server. If you have a consumer which you want to stop, then you need to stop the consumer/route instead.
localWorkDirectory null When consuming, a local work directory can be used to store the remote file content directly in local files, to avoid loading the content into memory. This is beneficial, if you consume a very big remote file and thus can conserve memory. See below for more details.
passiveMode false FTP only: Specifies whether to use passive mode connections. Default is active mode {false).
securityProtocol TLS
FTPS only: Sets the underlying security protocol. The following values are defined: TLS: Transport Layer Security SSL: Secure Sockets Layer
disableSecureDataChannelDefaults false Camel 2.4: FTPS only: Whether or not to disable using default values for execPbsz and execProt when using secure data transfer. You can set this option to true if you want to be in absolute full control what the options execPbsz and execProt should be used.
download true Camel 2.11: Whether the FTP consumer should download the file. If this option is set to false, then the message body will be null, but the consumer will still trigger a Camel Exchange that has details about the file such as file name, file size, etc. It's just that the file will not be downloaded.
streamDownload false Camel 2.11: hether the consumer should download the entire file up front, the default behavior, or if it should pass an InputStream ead from the remote resource rather than an in-memory array as the in body of the amel Exchange.  his option is ignored if download s false r is localWorkDirectory is provided.  his option is useful for working with large remote files.
execProt null
Camel 2.4: FTPS only: Will by default use option P if secure data channel defaults hasn't been disabled. Possible values are: C: Clear S: Safe (SSL protocol only) E: Confidential (SSL protocol only) P: Private
execPbsz null Camel 2.4: FTPS only: This option specifies the buffer size of the secure data channel. If option useSecureDataChannel has been enabled and this option has not been explicit set, then value 0 is used.
isImplicit false FTPS only: Sets the security mode(implicit/explicit). Default is explicit (false).
knownHostsFile null SFTP only: Sets the known_hosts file, so that the SFTP endpoint can do host key verification.
knownHostsUri null SFTP only:Camel 2.11.1: Sets the known_hosts file (loaded from classpath by default), so that the SFTP endpoint can do host key verification.
keyPair null SFTP only:Camel 2.12.0: Sets the Java KeyPair for SSH public key authentication, it supports DSA or RSA keys.
privateKeyFile null SFTP only: Set the private key file to that the SFTP endpoint can do private key verification.
privateKeyUri null SFTP only:Camel 2.11.1: Set the private key file (loaded from classpath by default) to that the SFTP endpoint can do private key verification.
privateKey null SFTP only:Camel 2.11.1: Set the private key as byte[] to that the SFTP endpoint can do private key verification.
privateKeyFilePassphrase null SFTP only: Set the private key file passphrase to that the SFTP endpoint can do private key verification.
privateKeyPassphrase null SFTP only:Camel 2.11.1: Set the private key file passphrase to that the SFTP endpoint can do private key verification.
preferredAuthentications null SFTP only:Camel 2.10.7, 2.11.2,2.12.0: set the preferred authentications which SFTP endpoint will used. Some example include:password,publickey. If not specified the default list from JSCH will be used.
ciphers null Camel 2.8.2, 2.9: SFTP only Set a comma separated list of ciphers that will be used in order of preference. Possible cipher names are defined by JCraft JSCH. Some examples include: aes128-ctr,aes128-cbc,3des-ctr,3des-cbc,blowfish-cbc,aes192-cbc,aes256-cbc. If not specified the default list from JSCH will be used.
fastExistsCheck false Camel 2.8.2, 2.9: If set this option to be true, camel-ftp will use the list file directly to check if the file exists. Since some FTP server may not support to list the file directly, if the option is false, camel-ftp will use the old way to list the directory and check if the file exists. Note from Camel 2.10.1 onwards this option also influences readLock=changed to control whether it performs a fast check to update file information or not. This can be used to speed up the process if the FTP server has a lot of files.
strictHostKeyChecking no SFTP only:Camel 2.2: Sets whether to use strict host key checking. Possible values are: no, yes and ask. ask does not make sense to use as Camel cannot answer the question for you as its meant for human intervention. Note: The default in Camel 2.1 and below was ask.
maximumReconnectAttempts 3 Specifies the maximum reconnect attempts Apache Camel performs when it tries to connect to the remote FTP server. Use 0 to disable this behavior.
reconnectDelay 1000 Delay in millis Apache Camel will wait before performing a reconnect attempt.
connectTimeout 10000 Camel 2.4: Is the connect timeout in millis. This corresponds to using ftpClient.connectTimeout for the FTP/FTPS. For SFTP this option is also used when attempting to connect.
soTimeout null FTP and FTPS Only:Camel 2.4: Is the SocketOptions.SO_TIMEOUT value in millis. Note SFTP will automatic use the connectTimeout as the soTimeout.
timeout 30000 FTP and FTPS Only:Camel 2.4: Is the data timeout in millis. This corresponds to using ftpClient.dataTimeout for the FTP/FTPS. For SFTP there is no data timeout.
throwExceptionOnConnectFailed false Camel 2.5: Whether or not to thrown an exception if a successful connection and login could not be establish. This allows a custom pollStrategy to deal with the exception, for example to stop the consumer or the likes.
siteCommand null FTP and FTPS Only:Camel 2.5: To execute site commands after successful login. Multiple site commands can be separated using a new line character (\n). Use help site to see which site commands your FTP server supports.
stepwise true When consuming directories, specifies whether or not to use stepwise mode for traversing the directory tree. Stepwise means that it will CD one directory at a time. For more details, see the section called “Stepwise changing directories”.
separator Auto Camel 2.6: Dictates what path separator char to use when uploading files. Auto means use the path provided without altering it. UNIX means use UNIX style path separators. Windows means use Windows style path separators.
chmod null *SFTP Producer Only:* Camel 2.9: Allows you to set chmod on the stored file. For example chmod=640.
compression 0 *SFTP Only:* Camel 2.8.3/2.9: To use compression. Specify a level from 1 to 10. Important: You must manually add the needed JSCH zlib JAR to the classpath for compression support.
ftpClient null FTP and FTPS Only:Camel 2.1: Allows you to use a custom org.apache.commons.net.ftp.FTPClient instance.
ftpClientConfig null FTP and FTPS Only:Camel 2.1: Allows you to use a custom org.apache.commons.net.ftp.FTPClientConfig instance.
serverAliveInterval 0 SFTP Only:Camel 2.8 Allows you to set the serverAliveInterval of the sftp session
serverAliveCountMax 1 SFTP Only:Camel 2.8 Allows you to set the serverAliveCountMax of the sftp session
ftpClient.trustStore.file null FTPS Only: Sets the trust store file, so that the FTPS client can look up for trusted certificates.
ftpClient.trustStore.type JKS FTPS Only: Sets the trust store type.
ftpClient.trustStore.algorithm SunX509 FTPS Only: Sets the trust store algorithm.
ftpClient.trustStore.password null FTPS Only: Sets the trust store password.
ftpClient.keyStore.file null FTPS Only: Sets the key store file, so that the FTPS client can look up for the private certificate.
ftpClient.keyStore.type JKS FTPS Only: Sets the key store type.
ftpClient.keyStore.algorithm SunX509 FTPS Only: Sets the key store algorithm.
ftpClient.keyStore.password null FTPS Only: Sets the key store password.
ftpClient.keyStore.keyPassword null FTPS Only: Sets the private key password.
sslContextParameters null FTPS Only:Camel 2.9: Reference to a org.apache.camel.util.jsse.SSLContextParameters in the Registry. This reference overrides any configured SSL related options on ftpClient as well as the securityProtocol (SSL, TLS, etc.) set on FtpsConfiguration. See Using the JSSE Configuration Utility.
proxy null SFTP Only:Camel 2.10.7, 2.11.1: Reference to a com.jcraft.jsch.Proxy in the Registry. This proxy is used to consume/send messages from the target SFTP host.
useList true FTP/FTPS Only:Camel 2.12.1: Whether the consumer should use FTP LIST command to retrieve directory listing to see which files exists. If this option is set to false, then stepwise=false must be configured, and also fileName must be configured to a fixed name, so the consumer knows the name of the file to retrieve. When doing this only that single file can be retrieved. See further below for more details.
ignoreFileNotFoundOrPermissionError false Camel 2.12.1: Whether the consumer should ignore when a file was attempted to be retrieved but did not exist (for some reason), or failure due insufficient file permission error.

FTPS component default trust store

When using the ftpClient. properties related to SSL with the FTPS component, the trust store accept all certificates. If you only want trust selective certificates, you have to configure the trust store with the ftpClient.trustStore.xxx options or by configuring a custom ftpClient.
When using sslContextParameters, the trust store is managed by the configuration of the provided SSLContextParameters instance.

More options

See File for more options, as all the options from File are inherited by FTP2.
You can configure additional options on the ftpClient and ftpClientConfig from the URI directly by using the ftpClient. or ftpClientConfig. prefix.
For example to set the setDataTimeout on the FTPClient to 30 seconds you can do:
from("ftp://foo@myserver?password=secret&ftpClient.dataTimeout=30000")
    .to("bean:foo");
You can mix and match and have use both prefixes, for example to configure date format or timezones.
from("ftp://foo@myserver?password=secret&ftpClient.dataTimeout=30000&ftpClientConfig.serverLanguageCode=fr")
    .to("bean:foo");
You can have as many of these options as you like.
See the documentation of the Apache Commons FTP FTPClientConfig for possible options and more details. And as well for Apache Commons FTP FTPClient.
If you do not like having many and long configuration in the url you can refer to the ftpClient or ftpClientConfig to use by letting Camel lookup in the Registry for it.
For example:
   <bean id="myConfig" class="org.apache.commons.net.ftp.FTPClientConfig">
       <property name="lenientFutureDates" value="true"/>
       <property name="serverLanguageCode" value="fr"/>
   </bean>

And then let Camel lookup this bean when you use the # notation in the url.
from("ftp://foo@myserver?password=secret&ftpClientConfig=#myConfig").to("bean:foo");

More URI options

Important

See File2 as all the options there also applies for this component.

Examples

Here are some examples of FTP endpoint URIs:
ftp://someone@someftpserver.com/public/upload/images/holiday2008?password=secret&binary=true
ftp://someoneelse@someotherftpserver.co.uk:12049/reports/2008/password=secret&binary=false
ftp://publicftpserver.com/download

FTP Consumer does not support concurrency

The FTP consumer (with the same endpoint) does not support concurrency (the backing FTP client is not thread safe). You can use multiple FTP consumers to poll from different endpoints. It is only a single endpoint that does not support concurrent consumers.
The FTP producer does not have this issue, it supports concurrency.

More information

This component is an extension of the File2 component. So there are more samples and details on the File2 component page.

Default when consuming files

The FTP consumer will by default leave the consumed files untouched on the remote FTP server. You have to configure it explicit if you want it to delete the files or move them to another location. For example you can use delete=true to delete the files, or use move=.done to move the files into a hidden done sub directory.
The regular File consumer is different as it will by default move files to a .camel sub directory. The reason Camel does not do this by default for the FTP consumer is that it may lack permissions by default to be able to move or delete files.

limitations

The option readLock can be used to force Apache Camel not to consume files that are currently in the process of being written. However, this option is turned off by default, as it requires that the user has write access. There are other solutions to avoid consuming files that are currently being written over FTP; for instance, you can write to a temporary destination and move the file after it has been written.
The ftp producer does not support appending to existing files. Any existing files on the remote server will be deleted before the file is written.

Message Headers

The following message headers can be used to affect the behavior of the component
Header Description
CamelFileName Specifies the output file name (relative to the endpoint directory) to be used for the output message when sending to the endpoint. If this is not present and no expression either, then a generated message ID is used as the filename instead.
CamelFileNameProduced The actual absolute filepath (path + name) for the output file that was written. This header is set by Apache Camel and its purpose is providing end-users the name of the file that was written.
CamelFileBatchIndex Current index out of total number of files being consumed in this batch.
CamelFileBatchSize Total number of files being consumed in this batch.
CamelFileHost The remote hostname.
CamelFileLocalWorkPath Path to the local work file, if local work directory is used.
In addition the FTP/FTPS consumer and producer will enrich the Camel Message with the following headers:
Header Description
CamelFtpReplyCode Camel 2.11.1: The FTP client reply code (the type is a integer)
CamelFtpReplyString Camel 2.11.1: The FTP client reply string

About timeouts

The two sets of libraries (see above) have different APIs for setting the timeout. You can use the connectTimeout option for both of them to set a timeout in milliseconds to establish a network connection. An individual soTimeout can also be set on the FTP/FTPS, which corresponds to using ftpClient.soTimeout. Notice SFTP will automatically use connectTimeout as its soTimeout. The timeout option only applies for FTP/FTSP as the data timeout, which corresponds to the ftpClient.dataTimeout value. All timeout values are in milliseconds.

Using Local Work Directory

Apache Camel supports consuming from remote FTP servers and downloading the files directly into a local work directory. This avoids reading the entire remote file content into memory as it is streamed directly into the local file using FileOutputStream.
Apache Camel will store to a local file with the same name as the remote file, though with .inprogress as extension while the file is being downloaded. Afterwards, the file is renamed to remove the .inprogress suffix. And finally, when the Exchange is complete the local file is deleted.
So if you want to download files from a remote FTP server and store it as files then you need to route to a file endpoint such as:
from("ftp://someone@someserver.com?password=secret&localWorkDirectory=/tmp").to("file://inbox");

Optimization by renaming work file

The route above is ultra efficient as it avoids reading the entire file content into memory. It will download the remote file directly to a local file stream. The java.io.File handle is then used as the Exchange body. The file producer leverages this fact and can work directly on the work file java.io.File handle and perform a java.io.File.rename to the target filename. As Apache Camel knows it's a local work file, it can optimize and use a rename instead of a file copy, as the work file is meant to be deleted anyway.

Stepwise changing directories

Camel FTP can operate in two modes in terms of traversing directories when consuming files (for example, downloading) or producing files (for example, uploading):
  • stepwise
  • not stepwise
You may want to pick either one depending on your situation and security issues. Some Camel end users can only download files if they use stepwise, while others can only download if they do not. At least you have the choice to pick.
Note that stepwise changing of directory will in most cases only work when the user is confined to it's home directory and when the home directory is reported as /.
The difference between the two of them is best illustrated with an example. Suppose we have the following directory structure on the remote FTP server we need to traverse and download files:
      /
      /one
      /one/two
      /one/two/sub-a
      /one/two/sub-b
And that we have a file in each of sub-a (a.txt) and sub-b (b.txt) folder.

Using stepwise=true (default mode)

The following log shows the conversation between the FTP endpoint and the remote FTP server when the FTP endpoint is operating in stepwise mode:
      TYPE A
      200 Type set to A
      PWD
      257 "/" is current directory.
      CWD one
      250 CWD successful. "/one" is current directory.
      CWD two
      250 CWD successful. "/one/two" is current directory.
      SYST
      215 UNIX emulated by FileZilla
      PORT 127,0,0,1,17,94
      200 Port command successful
      LIST
      150 Opening data channel for directory list.
      226 Transfer OK
      CWD sub-a
      250 CWD successful. "/one/two/sub-a" is current directory.
      PORT 127,0,0,1,17,95
      200 Port command successful
      LIST
      150 Opening data channel for directory list.
      226 Transfer OK
      CDUP
      200 CDUP successful. "/one/two" is current directory.
      CWD sub-b
      250 CWD successful. "/one/two/sub-b" is current directory.
      PORT 127,0,0,1,17,96
      200 Port command successful
      LIST
      150 Opening data channel for directory list.
      226 Transfer OK
      CDUP
      200 CDUP successful. "/one/two" is current directory.
      CWD /
      250 CWD successful. "/" is current directory.
      PWD
      257 "/" is current directory.
      CWD one
      250 CWD successful. "/one" is current directory.
      CWD two
      250 CWD successful. "/one/two" is current directory.
      PORT 127,0,0,1,17,97
      200 Port command successful
      RETR foo.txt
      150 Opening data channel for file transfer.
      226 Transfer OK
      CWD /
      250 CWD successful. "/" is current directory.
      PWD
      257 "/" is current directory.
      CWD one
      250 CWD successful. "/one" is current directory.
      CWD two
      250 CWD successful. "/one/two" is current directory.
      CWD sub-a
      250 CWD successful. "/one/two/sub-a" is current directory.
      PORT 127,0,0,1,17,98
      200 Port command successful
      RETR a.txt
      150 Opening data channel for file transfer.
      226 Transfer OK
      CWD /
      250 CWD successful. "/" is current directory.
      PWD
      257 "/" is current directory.
      CWD one
      250 CWD successful. "/one" is current directory.
      CWD two
      250 CWD successful. "/one/two" is current directory.
      CWD sub-b
      250 CWD successful. "/one/two/sub-b" is current directory.
      PORT 127,0,0,1,17,99
      200 Port command successful
      RETR b.txt
      150 Opening data channel for file transfer.
      226 Transfer OK
      CWD /
      250 CWD successful. "/" is current directory.
      QUIT
      221 Goodbye
      disconnected.                                                 

As you can see when stepwise is enabled, it will traverse the directory structure using CD xxx.

Using stepwise=false

The following log shows the conversation between the FTP endpoint and the remote FTP server when the FTP endpoint is operating in non-stepwise mode:
      230 Logged on
      TYPE A
      200 Type set to A
      SYST
      215 UNIX emulated by FileZilla
      PORT 127,0,0,1,4,122
      200 Port command successful
      LIST one/two
      150 Opening data channel for directory list
      226 Transfer OK
      PORT 127,0,0,1,4,123
      200 Port command successful
      LIST one/two/sub-a
      150 Opening data channel for directory list
      226 Transfer OK
      PORT 127,0,0,1,4,124
      200 Port command successful
      LIST one/two/sub-b
      150 Opening data channel for directory list
      226 Transfer OK
      PORT 127,0,0,1,4,125
      200 Port command successful
      RETR one/two/foo.txt
      150 Opening data channel for file transfer.
      226 Transfer OK
      PORT 127,0,0,1,4,126
      200 Port command successful
      RETR one/two/sub-a/a.txt
      150 Opening data channel for file transfer.
      226 Transfer OK
      PORT 127,0,0,1,4,127
      200 Port command successful
      RETR one/two/sub-b/b.txt
      150 Opening data channel for file transfer.
      226 Transfer OK
      QUIT
      221 Goodbye
      disconnected.                              

As you can see when not using stepwise, there are no CD operation invoked at all.

Samples

In the sample below we set up Apache Camel to download all the reports from the FTP server once every hour (60 min) as BINARY content and store it as files on the local file system.
protected RouteBuilder createRouteBuilder() throws Exception {
    return new RouteBuilder() {
        public void configure() throws Exception {
            // we use a delay of 60 minutes (eg. once pr. hour we poll the FTP server
            long delay = 60 * 60 * 1000L;

            // from the given FTP server we poll (= download) all the files
            // from the public/reports folder as BINARY types and store this as files
            // in a local directory. Apache Camel will use the filenames from the FTPServer

            // notice that the FTPConsumer properties must be prefixed with "consumer." in the URL
            // the delay parameter is from the FileConsumer component so we should use consumer.delay as
            // the URI parameter name. The FTP Component is an extension of the File Component.
            from("ftp://tiger:scott@localhost/public/reports?binary=true&consumer.delay=" + delay).
                to("file://target/test-reports");
        }
    };
}
And the route using Spring DSL:
  <route>
     <from uri="ftp://scott@localhost/public/reports?password=tiger&inary=true&elay=60000"/>
     <to uri="file://target/test-reports"/>
  </route>

Consuming a remote FTP server triggered by a route

The FTP consumer is built as a scheduled consumer to be used in the from route. However, if you want to start consuming from an FTP server triggered within a route, use a route like the following:
from("seda:start")
   // define the file name so that only a single file is polled and deleted once retrieved
   .pollEnrich("ftp://admin@localhost:21/getme?password=admin&binary=false&fileName=myFile.txt&delete=true")
   .to("mock:result");

Consuming a remote FTPS server (implicit SSL) and client authentication

from("ftps://admin@localhost:2222/public/camel?password=admin&securityProtocol=SSL&isImplicit=true
      &ftpClient.keyStore.file=./src/test/resources/server.jks
      &ftpClient.keyStore.password=password&ftpClient.keyStore.keyPassword=password")
  .to("bean:foo");

Consuming a remote FTPS server (explicit TLS) and a custom trust store configuration

from("ftps://admin@localhost:2222/public/camel?password=admin&ftpClient.trustStore.file=./src/test/resources/server.jks&ftpClient.trustStore.password=password")
  .to("bean:foo");

Filter using org.apache.camel.component.file.GenericFileFilter

Apache Camel supports pluggable filtering strategies. You define a filter strategy by implementing the org.apache.camel.component.file.GenericFileFilter interface in Java. You can then configure the endpoint with the filter to skip certain files.
In the following sample we define a filter that only accepts files whose filename starts with report.
public class MyFileFilter<T> implements GenericFileFilter<T> {

    public boolean accept(GenericFile<T> file) {
        // we only want report files 
        return file.getFileName().startsWith("report");
    }
}
And then we can configure our route using the filter attribute to reference our filter (using # notation) that we have defined in the spring XML file:
   <!-- define our sorter as a plain spring bean -->
   <bean id="myFilter" class="com.mycompany.MyFileFilter"/>

  <route>
    <from uri="ftp://someuser@someftpserver.com?password=secret&filter=#myFilter"/>
    <to uri="bean:processInbox"/>
  </route>

Filtering using ANT path matcher

The ANT path matcher is a filter that is shipped out-of-the-box in the camel-spring jar. So you need to depend on camel-spring if you are using Maven. The reason is that we leverage Spring's AntPathMatcher to do the actual matching.
The file paths are matched with the following rules:
  • ? matches one character
  • * matches zero or more characters
  • ** matches zero or more directories in a path
The sample below demonstrates how to use it:
<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"/>
<camelContext xmlns="http://camel.apache.org/schema/spring">

    <template id="camelTemplate"/>

    <!-- use myFilter as filter to allow setting ANT paths for which files to scan for -->
    <endpoint id="myFTPEndpoint" uri="ftp://admin@localhost:${SpringFileAntPathMatcherRemoteFileFilterTest.ftpPort}/antpath?password=admin&ecursive=true&elay=10000&nitialDelay=2000&ilter=#myAntFilter"/>

    <route>
        <from ref="myFTPEndpoint"/>
        <to uri="mock:result"/>
    </route>
</camelContext>

<!-- we use the AntPathMatcherRemoteFileFilter to use ant paths for includes and exclude -->
<bean id="myAntFilter" class="org.apache.camel.component.file.AntPathMatcherGenericFileFilter">
    <!-- include any files in the sub-folder that have day in the name -->
    <property name="includes" value="**/subfolder/**/*day*"/>
    <!-- exclude all files with bad in name or .xml files. Use comma to seperate multiple excludes -->
    <property name="excludes" value="**/*bad*,**/*.xml"/>
</bean>

Using a proxy with SFTP

To use an HTTP proxy to connect to your remote host, you can configure your route in the following way:
<!-- define our sorter as a plain spring bean -->
<bean id="proxy" class="com.jcraft.jsch.ProxyHTTP">
  <constructor-arg value="localhost"/>
  <constructor-arg value="7777"/>
</bean>

<route>
  <from uri="sftp://localhost:9999/root?username=admin&password=admin&proxy=#proxy"/>
  <to uri="bean:processFile"/>
</route>
You can also assign a user name and password to the proxy, if necessary. Please consult the documentation for com.jcraft.jsch.Proxy to discover all options.

Consuming a single file using a fixed name

When you want to download a single file and knows the file name, you can use fileName=myFileName.txt to tell Camel the name of the file to download. By default the consumer will still do a FTP LIST command to do a directory listing and then filter these files based on the fileName option. Though in this use-case it may be desirable to turn off the directory listing by setting useList=false. For example the user account used to login to the FTP server may not have permission to do a FTP LIST command. So you can turn off this with useList=false, and then provide the fixed name of the file to download with fileName=myFileName.txt, then the FTP consumer can still download the file. If the file for some reason does not exist, then Camel will by default throw an exception, you can turn this off and ignore this by setting ignoreFileNotFoundOrPermissionError=true.
For example to have a Camel route that pickup a single file, and delete it after use you can do
from("ftp://admin@localhost:21/nolist/?password=admin&stepwise=false&useList=false&ignoreFileNotFoundOrPermissionError=true&fileName=report.txt&delete=true")
  .to("activemq:queue:report");
Notice that we have use all the options we talked above above.
You can also use this with ConsumerTemplate. For example to download a single file (if it exists) and grab the file content as a String type:
String data = template.retrieveBodyNoWait("ftp://admin@localhost:21/nolist/?password=admin&stepwise=false&useList=false&ignoreFileNotFoundOrPermissionError=true&fileName=report.txt&delete=true", String.class);

Debug logging

This component has log level TRACE that can be helpful if you have problems.

Chapter 41. GAE

41.1. Introduction to the GAE Components

Apache Camel Components for Google App Engine

Tutorials

The Apache Camel components for Google App Engine (GAE) are part of the camel-gae project and provide connectivity to GAE's cloud computing services. They make the GAE cloud computing environment accessible to applications via Apache Camel interfaces. Following this pattern for other cloud computing environments could make it easier to port Apache Camel applications from one cloud computing provider to another. The following table lists the cloud computing services provided by Google App Engine and the supporting Apache Camel components. The documentation of each component can be found by following the link in the Camel Component column.
GAE service Camel component Component description
URL fetch service ghttp Provides connectivity to the GAE URL fetch service but can also be used to receive messages from servlets.
Task queueing service gtask Supports asynchronous message processing on GAE by using the task queueing service as message queue.
Mail service gmail Supports sending of emails via the GAE mail service. Receiving mails is not supported yet but will be added later.
Memcache service Not supported yet.
XMPP service Not supported yet.
Images service Not supported yet.
Datastore service Not supported yet.
Accounts service gauth glogin These components interact with the Google Accounts API for authentication and authorization. Google Accounts is not specific to Google App Engine but is often used by GAE applications for implementing security. The gauth component is used by web applications to implement a Google-specific OAuth consumer. This component can also be used to OAuth-enable non-GAE web applications. The glogin component is used by Java clients (outside GAE) for programmatic login to GAE applications. For instructions how to protect GAE applications against unauthorized access refer to the Security for page.

Camel context

Setting up a SpringCamelContext on Google App Engine differs between Camel 2.1 and higher versions. The problem is that usage of the Camel-specific Spring configuration XML schema from the http://camel.apache.org/schema/spring namespace requires JAXB and Camel 2.1 depends on a Google App Engine SDK version that doesn't support JAXB yet. This limitation has been removed since Camel 2.2.
JMX must be disabled in any case because the javax.management package isn't on the App Engine JRE whitelist.

Apache Camel 2.1

camel-gae 2.1 comes with the following CamelContext implementations.
  • org.apache.camel.component.gae.context.GaeDefaultCamelContext (extends org.apache.camel.impl.DefaultCamelContext)
  • org.apache.camel.component.gae.context.GaeSpringCamelContext (extends org.apache.camel.spring.SpringCamelContext)
Both disable JMX before startup. The GaeSpringCamelContext additionally provides setter methods adding route builders as shown in the next example.

appctx.xml

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">
    
    <bean id="camelContext" 
        class="org.apache.camel.component.gae.context.GaeSpringCamelContext">
        <property name="routeBuilder" ref="myRouteBuilder" />
    </bean>
    
    <bean id="myRouteBuilder"
        class="org.example.MyRouteBuilder">
    </bean>
    
</beans>
Alternatively, use the routeBuilders property of the GaeSpringCamelContext for setting a list of route builders. Using this approach, a SpringCamelContext can be configured on GAE without the need for JAXB.

Apache Camel 2.2

With Camel 2.2 or higher, applications can use the http://camel.apache.org/schema/spring namespace for configuring a SpringCamelContext but still need to disable JMX. Here's an example.

appctx.xml

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:camel="http://camel.apache.org/schema/spring"
       xsi:schemaLocation="
http://www.springframework.org/schema/beans 
http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
http://camel.apache.org/schema/spring
http://camel.apache.org/schema/spring/camel-spring.xsd">
    
    <camel:camelContext id="camelContext">
        <camel:jmxAgent id="agent" disabled="true" />
        <camel:routeBuilder ref="myRouteBuilder"/>
    </camel:camelContext>
    
    <bean id="myRouteBuilder"
        class="org.example.MyRouteBuilder">
    </bean>
    
</beans>

The web.xml

Running Apache Camel on GAE requires usage of the CamelHttpTransportServlet from camel-servlet. The following example shows how to configure this servlet together with a Spring application context XML file.

web.xml

<web-app 
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
xsi:schemaLocation="
http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" version="2.5">
    
    <servlet>
        <servlet-name>CamelServlet</servlet-name>
        <servlet-class>org.apache.camel.component.servlet.CamelHttpTransportServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>appctx.xml</param-value>
        </init-param>
    </servlet>

    <!--
        Mapping used for external requests
     -->
    <servlet-mapping>
        <servlet-name>CamelServlet</servlet-name>
        <url-pattern>/camel/*</url-pattern>
    </servlet-mapping>
    
    <!--
        Mapping used for web hooks accessed by task queueing service.
     -->
    <servlet-mapping>
        <servlet-name>CamelServlet</servlet-name>
        <url-pattern>/worker/*</url-pattern>
    </servlet-mapping>

</web-app>
The location of the Spring application context XML file is given by the contextConfigLocation init parameter. The appctx.xml file must be on the classpath. The servlet mapping makes the Apache Camel application accessible under http://<appname>.appspot.com/camel/... when deployed to Google App Engine where <appname> must be replaced by a real GAE application name. The second servlet mapping is used internally by the task queueing service for background processing via web hooks. This mapping is relevant for the gtask component and is explained there in more detail.

41.2. gauth

gauth Component

Available in Apache Camel 2.3
The gauth component is used by web applications to implement a Google-specific OAuth consumer. It will be later extended to support other OAuth providers as well. Although this component belongs to the Camel Components for Google App Engine (GAE), it can also be used to OAuth-enable non-GAE web applications. For a detailed description of Google's OAuth implementation refer to the Google OAuth API reference.

URI format

gauth://name[?options]
The endpoint name can be either authorize or upgrade. An authorize endpoint is used to obtain an unauthorized request token from Google and to redirect the user to the authorization page. The upgrade endpoint is used to process OAuth callbacks from Google and to upgrade an authorized request token to a long-lived access token. Refer to the usage section for an example.

Options

Name Default Value Required Description
callback null true (can alternatively be set via GAuthAuthorizeBinding.GAUTH_CALLBACK message header) URL where to redirect the user after having granted or denied access.
scope null true (can alternatively be set via GAuthAuthorizeBinding.GAUTH_SCOPE message header) URL identifying the service(s) to be accessed. Scopes are defined by each Google service; see the service's documentation for the correct value. To specify more than one scope, list each one separated with a comma. Example: http://www.google.com/calendar/feeds/ .
consumerKey null true (can alternatively be set on component-level). Domain identifying the web application. This is the domain used when registering the application with Google. Example: camelcloud.appspot.com. For a non-registered application use anonymous.
consumerSecret null one of consumerSecret or keyLoaderRef is required (can alternatively be set on component-level). Consumer secret of the web application. The consumer secret is generated when when registering the application with Google. It is needed if the HMAC-SHA1 signature method shall be used. For a non-registered application use anonymous.
keyLoaderRef null one of consumerSecret or keyLoaderRef is required (can be alternatively set on component-level) Reference to a private key loader in the registry. Part of camel-gae are two key loaders: GAuthPk8Loader for loading a private key from a PKCS#8 file and GAuthJksLoader to load a private key from a Java key store. It is needed if the RSA-SHA1 signature method shall be used. These classes are defined in the org.apache.camel.component.gae.auth package.
authorizeBindingRef Reference to GAuthAuthorizeBinding false Reference to a OutboundBinding<GAuthEndpoint, GoogleOAuthParameters, GoogleOAuthParameters> in the registry for customizing how an Exchange is bound to GoogleOAuthParameters. This binding is used for teh authorization phase. Most applications won't change the default value.
upgradeBindingRef Reference to GAuthAuthorizeBinding false Reference to a OutboundBinding<GAuthEndpoint, GoogleOAuthParameters, GoogleOAuthParameters> in the registry. for customizing how an Exchange is bound to GoogleOAuthParameters. This binding is used for teh token upgrade phase. Most applications won't change the default value.

Message headers

Name Type Endpoint Message Description
GAuthAuthorizeBinding.GAUTH_CALLBACK String gauth:authorize in Overrides the callback option.
GAuthAuthorizeBinding.GAUTH_SCOPE String gauth:authorize in Overrides the scope option.
GAuthUpgradeBinding.GAUTH_ACCESS_TOKEN String gauth:upgrade out Contains the long-lived access token. This token should be stored by the applications in context of a user.
GAuthUpgradeBinding.GAUTH_ACCESS_TOKEN_SECRET String gauth:upgrade out Contains the access token secret. This token secret should be stored by the applications in context of a user.

Message body

The gauth component doesn't read or write message bodies.

Component configuration

Some endpoint options such as consumerKey, consumerSecret or keyLoader are usually set to the same values on gauth:authorize and gauth:upgrade endpoints. The gauth component allows to configure them on component-level. These settings are then inherited by gauth endpoints and need not be set redundantly in the endpoint URIs. Here are some configuration examples.

component configuration for a registered web application using the HMAC-SHA1 signature method

<bean id="gauth" class="org.apache.camel.component.gae.auth.GAuthComponent">
    <property name="consumerKey" value="example.appspot.com" />
    <property name="consumerSecret" value="QAtA...HfQ" />
</bean>

component configuration for an unregistered web application using the HMAC-SHA1 signature method

<bean id="gauth" class="org.apache.camel.component.gae.auth.GAuthComponent">
    <!-- Google will display a warning message on the authorization page -->
    <property name="consumerKey" value="anonymous" />
    <property name="consumerSecret" value="anonymous" />
</bean>

component configuration for a registered web application using the RSA-SHA1 signature method

<bean id="gauth" class="org.apache.camel.component.gae.auth.GAuthComponent">
    <property name="consumerKey" value="ipfcloud.appspot.com" />
    <property name="keyLoader" ref="jksLoader" />
    <!--<property name="keyLoader" ref="pk8Loader" />-->
</bean>

<!-- Loads the private key from a Java key store -->
<bean id="jksLoader"
    class="org.apache.camel.component.gae.auth.GAuthJksLoader">
    <property name="keyStoreLocation" value="myKeytore.jks" />
    <property name="keyAlias" value="myKey" />
    <property name="keyPass" value="myKeyPassword" />
    <property name="storePass" value="myStorePassword" />
</bean>

<!-- Loads the private key from a PKCS#8 file -->
<bean id="pk8Loader"
    class="org.apache.camel.component.gae.auth.GAuthPk8Loader">
    <property name="keyStoreLocation" value="myKeyfile.pk8" />
</bean>

Usage

Here's the minimum setup for adding OAuth to a (non-GAE) web application. In the following example, it is assumed that the web application is running on gauth.example.org.

GAuthRouteBuilder.java

import java.net.URLEncoder;
import org.apache.camel.builder.RouteBuilder;

public class GAuthRouteBuilder extends RouteBuilder {

    @Override
    public void configure() throws Exception {

        // Calback URL to redirect user from Google Authorization back to the web application
        String encodedCallback = URLEncoder.encode("https://gauth.example.org:8443/handler", "UTF-8");
        // Application will request for authorization to access a user's Google Calendar
        String encodedScope = URLEncoder.encode("http://www.google.com/calendar/feeds/", "UTF-8");

        // Route 1: A GET request to http://gauth.example.org/authorize will trigger the the OAuth
        // sequence of interactions. The gauth:authorize endpoint obtains an unauthorized request
        // token from Google and then redirects the user (browser) to a Google authorization page.
        from("jetty:http://0.0.0.0:8080/authorize")
            .to("gauth:authorize?callback=" + encodedCallback + "&scope=" + encodedScope);

        // Route 2: Handle callback from Google. After the user granted access to Google Calendar
        // Google redirects the user to https://gauth.example.org:8443/handler (see callback) along
        // with an authorized request token. The gauth:access endpoint exchanges the authorized
        // request token against a long-lived access token.
        from("jetty:https://0.0.0.0:8443/handler")
            .to("gauth:upgrade")
            // The access token can be obtained from
            // exchange.getOut().getHeader(GAuthUpgradeBinding.GAUTH_ACCESS_TOKEN)
            // The access token secret can be obtained from
            // exchange.getOut().getHeader(GAuthUpgradeBinding.GAUTH_ACCESS_TOKEN_SECRET)
            .process(/* store the tokens in context of the current user ... */);
    }

}

The OAuth sequence is triggered by sending a GET request to http://gauth.example.org/authorize . The user is then redirected to a Google authorization page. After having granted access on this page, Google redirects the user to the web application which handles the callback and finally obtains a long-lived access token from Google.
These two routes can perfectly co-exist with any other web application framework. The framework provides the basis for web application-specific functionality whereas the OAuth service provider integration is done with Apache Camel. The OAuth integration part could even use resources from an existing servlet container by using the servlet component instead of the jetty component.

What to do with the OAuth access token?

  • Application should store the access token in context of the current user. If the user logs in next time, the access token can directly be loaded from the database, for example, without doing the OAuth dance again.
  • The access token is then used to get access to Google services, such as a Google Calendar API, on behalf of the user. Java applications will most likely use the GData Java library for that. See below for an example how to use the access token with the GData Java library to read a user's calendar feed.
  • The user can revoke the access token at any time from his Google Accounts page. In this case, access to the corresponding Google service will throw an authorization exception. The web application should remove the stored access token and redirect the user again to the Google authorization page for creating another one.
The above example relies on the following component configuration.
<bean id="gauth" class="org.apache.camel.component.gae.auth.GAuthComponent">
    <property name="consumerKey" value="anonymous" />
    <property name="consumerSecret" value="anonymous" />
</bean>

If you don't want that Google displays a warning message on the authorization page, you'll need to register your web application and change the consumerKey and consumerSecret settings.

GAE example

To OAuth-enable a Google App Engine application, only some small changes in the route builder are required. Assuming the GAE application hostname is camelcloud.appspot.com a configuration might look as follows. Here, the ghttp component is used to handle HTTP(S) requests instead of the jetty component.

GAuthRouteBuilder

import java.net.URLEncoder;
import org.apache.camel.builder.RouteBuilder;

public class TutorialRouteBuilder extends RouteBuilder {

    @Override
    public void configure() throws Exception {

        String encodedCallback = URLEncoder.encode("https://camelcloud.appspot.com/handler", "UTF-8");
        String encodedScope = URLEncoder.encode("http://www.google.com/calendar/feeds/", "UTF-8");

        from("ghttp:///authorize")
            .to("gauth:authorize?callback=" + encodedCallback + "&scope=" + encodedScope);

        from("ghttp:///handler")
            .to("gauth:upgrade")
            .process(/* store the tokens in context of the current user ... */);
    }

}

Access token usage

Here's an example how to use an access token to access a user's Google Calendar data with the GData Java library. The example application writes the titles of the user's public and private calendars to stdout.

Access token usage

import com.google.gdata.client.authn.oauth.OAuthHmacSha1Signer;
import com.google.gdata.client.authn.oauth.OAuthParameters;
import com.google.gdata.client.calendar.CalendarService;
import com.google.gdata.data.calendar.CalendarEntry;
import com.google.gdata.data.calendar.CalendarFeed;

import java.net.URL;

public class AccessExample {

    public static void main(String... args) throws Exception {
        String accessToken = ...
        String accessTokenSecret = ...

        CalendarService myService = new CalendarService("exampleCo-exampleApp-1.0");
        OAuthParameters params = new OAuthParameters();
        params.setOAuthConsumerKey("anonymous");
        params.setOAuthConsumerSecret("anonymous");
        params.setOAuthToken(accessToken);
        params.setOAuthTokenSecret(accessTokenSecret);
        myService.setOAuthCredentials(params, new OAuthHmacSha1Signer());

        URL feedUrl = new URL("http://www.google.com/calendar/feeds/default/");
        CalendarFeed resultFeed = myService.getFeed(feedUrl, CalendarFeed.class);

        System.out.println("Your calendars:");
        System.out.println();

        for (int i = 0; i < resultFeed.getEntries().size(); i++) {
            CalendarEntry entry = resultFeed.getEntries().get(i);
            System.out.println(entry.getTitle().getPlainText());
        }
    }
}

41.3. ghttp

ghttp Component

The ghttp component contributes to the Camel Components for Google App Engine (GAE). It provides connectivity to the GAE URL fetch service but can also be used to receive messages from servlets (the only way to receive HTTP requests on GAE). This is achieved by extending the Servlet component. As a consequence, ghttp URI formats and options sets differ on the consumer-side (from) and producer-side (to).

URI format

Format Context Comment
ghttp:///path[?options]
Consumer See also Servlet component
ghttp://hostname[:port][/path][?options]
ghttps://hostname[:port][/path][?options]
Producer See also Http component

Options

Name Default Value Context Description
bridgeEndpoint true Producer If set to true the Exchange.HTTP_URI header will be ignored. To override the default endpoint URI with the Exchange.HTTP_URI header set this option to false.
throwExceptionOnFailure true Producer Throw a org.apache.camel.component.gae.http if the response code is >= 400. To disable throwing an exception set this option to false.
inboundBindingRef reference to GHttpBinding Consumer Reference to an InboundBinding<GHttpEndpoint, HttpServletRequest, HttpServletResponse> in the Registry for customizing the binding of an Exchange to the Servlet API. The referenced binding is used as post-processor to org.apache.camel.component.http.HttpBinding.
outboundBindingRef reference to GHttpBinding Producer Reference to an OutboundBinding<GHttpEndpoint, HTTPRequest, HTTPResponse> in the Registry for customizing the binding of an Exchange to the URLFetchService.
On the consumer-side, all options of the Servlet component are supported.

Message headers

On the producer side, the following headers of the Http component are supported.
Name Type Description
Exchange.CONTENT_TYPE String The HTTP content type. Is set on both the in and out message to provide a content type, such as text/html.
Exchange.CONTENT_ENCODING String The HTTP content encoding. Is set on both the in and out message to provide a content encoding, such as gzip.
Exchange.HTTP_METHOD String The HTTP method to execute. One of GET, POST, PUT and DELETE. If not set, POST will be used if the message body is not null, GET otherwise.
Exchange.HTTP_QUERY String Overrides the query part of the endpoint URI or the the query part of Exchange.HTTP_URI (if defined). The query string must be in decoded form.
Exchange.HTTP_URI String Overrides the default endpoint URI if the bridgeEndpoint option is set to false. The URI string must be in decoded form.
Exchange.RESPONSE_CODE int The HTTP response code from URL fetch service responses.
On the consumer-side all headers of the Servlet component component are supported.

Message body

On the producer side the in message body is converted to a byte[]. The out message body is made available as InputStream. If the reponse size exceeds 1 megabyte a ResponseTooLargeException is thrown by the URL fetch service (see quotas and limits).

Receiving messages

For receiving messages via the ghttp component, a CamelHttpTransportServlet must be configured and mapped in the application's web.xml (see the section called “The web.xml”). For example, to handle requests targeted at http://<appname>.appspot.com/camel/* or http://localhost/camel/* (when using a local development server) the following servlet mapping must be defined:

web.xml

    ...
    <servlet>
        <servlet-name>CamelServlet</servlet-name>
        <servlet-class>org.apache.camel.component.servlet.CamelHttpTransportServlet</servlet-class>
        ...
    </servlet>
    ...
    <servlet-mapping>
        <servlet-name>CamelServlet</servlet-name>
        <url-pattern>/camel/*</url-pattern>
    </servlet-mapping>
    ...
Endpoint URI path definitions are relative to this servlet mapping e.g. the route
from("ghttp:///greeting").transform().constant("Hello")
processes requests targeted at http://<appname>.appspot.com/camel/greeting. In this example, the request body is ignored and the response body is set to Hello. Requests targeted at http://<appname>.appspot.com/camel/greeting/* are not processed by default. This requires setting the option matchOnUriPrefix to true.
from("ghttp:///greeting?matchOnUriPrefix=true").transform().constant("Hello")

Sending messages

For sending resquests to external HTTP services the ghttp component uses the URL fetch service. For example, the Apache Camel homepage can the retrieved with the following endpoint definition on the producer-side.
from(...)
...
.to("ghttp://camel.apache.org")
...
The HTTP method used depends on the Exchange.HTTP_METHOD message header or on the presence of an in-message body (GET if null, POST otherwise). Retrieving the Camel homepage via a GAE application is as simple as
from("ghttp:///home")
.to("ghttp://camel.apache.org")
Sending a GET request to http://<appname>.appspot.com/camel/home returns the Camel homepage. HTTPS-based communication with external services can be enabled with the ghttps scheme.
from(...)
...
.to("ghttps://svn.apache.org/repos/asf/camel/trunk/")
...

Dependencies

Maven users will need to add the following dependency to their pom.xml.

pom.xml

<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-gae</artifactId>
    <version>${camel-version}</version>
</dependency>
where ${camel-version} must be replaced by the actual version of Apache Camel (2.1.0 or higher).

41.4. glogin

glogin Component

Available in Apache Camel 2.3 (or latest development snapshot).
The glogin component is used by Apache Camel applications outside Google App Engine (GAE) for programmatic login to GAE applications. It is part of the Chapter 41, GAE. Security-enabled GAE applications normally redirect the user to a login page. After submitting username and password for authentication, the user is redirected back to the application. That works fine for applications where the client is a browser. For all other applications, the login process must be done programmatically. All the necessary steps for programmatic login are implemented by the glogin component. These are
  1. Get an authentication token from Google Accounts via the ClientLogin API.
  2. Get an authorization cookie from Google App Engine's login API.
The authorization cookie must then be send with subsequent HTTP requests to the GAE application. It expires after 24 hours and must then be renewed.

URI format

glogin://hostname[:port][?options]
The hostname is either the internet hostname of a GAE application (e.g. camelcloud.appspot.com) or the name of the host where the development server is running (e.g. localhost). The port is only used when connecting to a development server (i.e. when devMode=true, see options) and defaults to 8080.

Options

Name Default Value Required Description
clientName apache-camel-2.x false A client name with recommended (but not required) format <organization>\-<appname>\-<version>.
userName null true (can alternatively be set via GLoginBinding.GLOGIN_USER_NAME message header) Login username (an email address).
password null true (can alternatively be set via GLoginBinding.GLOGIN_PASSWORD message header) Login password.
devMode false false If set to true a login to a development server is attempted.
devAdmin false false If set to true a login to a development server in admin role is attempted.

Message headers

Name Type Message Description
GLoginBinding.GLOGIN_HOST_NAME String in Overrides the hostname defined in the endpoint URI.
GLoginBinding.GLOGIN_USER_NAME String in Overrides the userName option.
GLoginBinding.GLOGIN_PASSWORD String in Overrides the password option.
GLoginBinding.GLOGIN_TOKEN String out Contains the authentication token obtained from Google Accounts. Login to a development server does not set this header.
GLoginBinding.GLOGIN_COOKIE String out Contains the application-specific authorization cookie obtained from Google App Engine (or a development server).

Message body

The glogin component doesn't read or write message bodies.

Usage

The following JUnit test show an example how to login to a development server as well as to a deployed GAE application located at http://camelcloud.appspot.com.

GLoginTest.java

import org.apache.camel.Exchange;
import org.apache.camel.Processor;
import org.apache.camel.ProducerTemplate;
import org.junit.Ignore;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import static org.apache.camel.component.gae.login.GLoginBinding.*;
import static org.junit.Assert.*;

public class GLoginTest {

    private ProducerTemplate template = ...

    @Test
    public void testDevLogin() {
        Exchange result = template.request("glogin://localhost:8888?userName=test@example.org&devMode=true", null);
        assertNotNull(result.getOut().getHeader(GLOGIN_COOKIE));
    }

    @Test
    public void testRemoteLogin() {
        Exchange result = template.request("glogin://camelcloud.appspot.com", new Processor() {
            public void process(Exchange exchange) throws Exception {
                exchange.getIn().setHeader(GLOGIN_USER_NAME, "replaceme@gmail.com");
                exchange.getIn().setHeader(GLOGIN_PASSWORD, "replaceme");
            }
        });
        assertNotNull(result.getOut().getHeader(GLOGIN_COOKIE));
    }

}
The resulting authorization cookie from login to a development server looks like
ahlogincookie=test@example.org:false:11223191102230730701;Path=/
The resulting authorization cookie from login to a deployed GAE application looks (shortened) like
ACSID=AJKiYcE...XxhH9P_jR_V3; expires=Sun, 07-Feb-2010 15:14:51 GMT; path=/

41.5. gmail

gmail Component

The gmail component contributes to the Camel Components for Google App Engine (GAE). It supports sending of emails via the GAE mail service. Receiving mails is not supported yet but will be added later. Currently, only Google accounts that are application administrators can send emails.

URI format

gmail://user@gmail.com[?options]
gmail://user@googlemail.com[?options]

Options

Name Default Value Context Description
to null Producer To-receiver of the email. This can be a single receiver or a comma-separated list of receivers.
cc null Producer Cc-receiver of the email. This can be a single receiver or a comma-separated list of receivers.
bcc null Producer Bcc-receiver of the email. This can be a single receiver or a comma-separated list of receivers.
subject null Producer Subject of the email.
outboundBindingRef reference to GMailBinding Producer Reference to an OutboundBinding<GMailEndpoint, MailService.Message, void> in the Registry for customizing the binding of an Exchange to the mail service.

Message headers

Name Type Context Description
GMailBinding.GMAIL_SUBJECT String Producer Subject of the email. Overrides subject endpoint option.
GMailBinding.GMAIL_SENDER String Producer Sender of the email. Overrides sender definition in endpoint URI.
GMailBinding.GMAIL_TO String Producer To-receiver(s) of the email. Overrides to endpoint option.
GMailBinding.GMAIL_CC String Producer Cc-receiver(s) of the email. Overrides cc endpoint option.
GMailBinding.GMAIL_BCC String Producer Bcc-receiver(s) of the email. Overrides bcc endpoint option.

Message body

On the producer side the in message body is converted to a String.

Usage

...
.setHeader(GMailBinding.GMAIL_SUBJECT, constant("Hello"))
.setHeader(GMailBinding.GMAIL_TO, constant("account2@somewhere.com"))
.to("gmail://account1@gmail.com");
Sends an email with subject Hello from account1@gmail.com to account2@somewhere.com. The mail message body is taken from the in message body. Please note that account1@gmail.com must be an administrator account for the current GAE application.

Dependencies

Maven users will need to add the following dependency to their pom.xml.

pom.xml

<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-gae</artifactId>
    <version>${camel-version}</version>
</dependency>
where $\{camel-version\} must be replaced by the actual version of Apache Camel (2.1.0 or higher).

41.6. gsec

Security for Apache Camel GAE Applications

Securing GAE applications from unauthorized access is described in the Security and Authentication section of the Google App Engine documentation. Authorization constraints are declared in the web.xml file (see the section called “The web.xml”). This applies to Apache Camel applications as well. In the following example, the application is configured to only allow authenticated users (in any role) to access the application. Additionally, access to /worker/\* URLs masy only be done by users in the admin role. By default, web hook URLs installed by the gtask component match the /worker/\* pattern and should not be accessed by normal users. With this authorization constraint, only the task queuing service (which is always in the admin role) is allowed to access the web hooks. For implementing custom, non-declarative authorization logic, Apache Camel GAE applications should use the Google Accounts Java API.

Example 41.1. web.xml with authorization constraint

<web-app 
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
xsi:schemaLocation="
http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" version="2.5">
    
    <servlet>
        <servlet-name>CamelServlet</servlet-name>
        <servlet-class>org.apache.camel.component.servlet.CamelHttpTransportServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>appctx.xml</param-value>
        </init-param>
    </servlet>

    <!--
        Mapping used for external requests
     -->
    <servlet-mapping>
        <servlet-name>CamelServlet</servlet-name>
        <url-pattern>/camel/*</url-pattern>
    </servlet-mapping>
    
    <!--
        Mapping used for web hooks accessed by task queueing service.
     -->
    <servlet-mapping>
        <servlet-name>CamelServlet</servlet-name>
        <url-pattern>/worker/*</url-pattern>
    </servlet-mapping>

    <!--
        By default allow any user who is logged in to access the whole 
        application.
     -->
    <security-constraint>
        <web-resource-collection>
            <url-pattern>/*</url-pattern>
        </web-resource-collection>
        <auth-constraint>
            <role-name>*</role-name>
        </auth-constraint>
    </security-constraint>

    <!--
        Allow only admin users to access /worker/* URLs e.g. to prevent
        normal user to access gtask web hooks.
     -->
    <security-constraint>
        <web-resource-collection>
            <url-pattern>/worker/*</url-pattern>
        </web-resource-collection>
        <auth-constraint>
            <role-name>admin</role-name>
        </auth-constraint>
    </security-constraint>

</web-app>

41.7. gtask

gtask Component

The gtask component contributes to the Camel Components for Google App Engine (GAE). It supports asynchronous message processing on GAE by using the task queueing service as message queue. For adding messages to a queue it uses the task queue API. For receiving messages from a queue it installs an HTTP callback handler. The handler is called by an HTTP POST callback (a web hook) initiated by the task queueing service. Whenever a new task is added to a queue a callback will be sent. The gtask component abstracts from these details and supports endpoint URIs that make message queueing on GAE as easy as message queueing with JMS or SEDA.

URI format

gtask://queue-name

Options

Name Default Value Context Description
workerRoot worker Producer The servlet mapping for callback handlers. By default, this component requires a callback servlet mapping of /worker/*. If another servlet mapping is used e.g. /myworker/* it must be set as option on the producer side: to("gtask:myqueue?workerRoot=myworker").
inboundBindingRef reference to GTaskBinding Consumer Reference to an InboundBinding<GTaskEndpoint, HttpServletRequest, HttpServletResponse> in the Registry for customizing the binding of an Exchange to the Servlet API. The referenced binding is used as post-processor to org.apache.camel.component.http.HttpBinding.
outboundBindingRef reference to GTaskBinding Producer Reference to an OutboundBinding<GTaskEndpoint, TaskOptions, void> in the Registry for customizing the binding of an Exchange to the task queueing service.
On the consumer-side, all options of the Servlet component are supported.

Message headers

On the consumer-side all headers of the Servlet component component are supported plus the following.
Name Type Context Description
GTaskBinding.GTASK_QUEUE_NAME String Consumer Name of the task queue.
GTaskBinding.GTASK_TASK_NAME String Consumer Name of the task (generated value).
GTaskBinding.GTASK_RETRY_COUNT int Consumer Number of callback retries.

Message body

On the producer side the in message body is converted to a byte[] and is POSTed to the callback handler as content-type application/octet-stream.

Usage

Setting up tasks queues is an administrative task on Google App Engine. Only one queue is pre-configured and can be referenced by name out-of-the-box: the default queue. This queue will be used in the following examples. Please note that when using task queues on the local development server, tasks must be executed manually from the developer console.

Default queue

...
.to(gtask:default) // add message to default queue

from(gtask:default) // receive message from default queue (via a web hook)
...
This example requires the following servlet mapping.

web.xml

    ...
    <servlet>
        <servlet-name>CamelServlet</servlet-name>
        <servlet-class>org.apache.camel.component.servlet.CamelHttpTransportServlet</servlet-class>
        ...
    </servlet>
    ...
    <servlet-mapping>
        <servlet-name>CamelServlet</servlet-name>
        <url-pattern>/worker/*</url-pattern>
    </servlet-mapping>
    ...

Dependencies

Maven users will need to add the following dependency to their pom.xml.

pom.xml

<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-gae</artifactId>
    <version>${camel-version}</version>
</dependency>
where ${camel-version} must be replaced by the actual version of Apache Camel (2.1.0 or higher).

Chapter 42. Geocoder

Geocoder Component

Available as of Camel 2.12
The geocoder: component is used for looking up geocodes (latitude and longitude) for a given address, or reverse lookup. The component uses the Java API for Google Geocoder library.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-geocoder</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

geocoder:address:name[?options]
geocoder:latlng:latitude,longitude[?options]

Options

Property Default Description
language en The language to use.
headersOnly false Whether to only enrich the Exchange with headers, and leave the body as-is.
clientId To use google premium with this client id
clientKey To use google premium with this client key
You can append query options to the URI in the following format, ?option=value&option=value&...

Exchange data format

Camel will deliver the body as a com.google.code.geocoder.model.GeocodeResponse type. And if the address is "current" then the response is a String type with a JSON representation of the current location.
If the option headersOnly is set to true then the message body is left as-is, and only headers will be added to the Exchange.

Message Headers

Header Description
CamelGeoCoderStatus Mandatory. Status code from the geocoder library. If status is GeocoderStatus.OK then additional headers is enriched
CamelGeoCoderAddress The formatted address
CamelGeoCoderLat The latitude of the location.
CamelGeoCoderLng The longitude of the location.
CamelGeoCoderLatlng The latitude and longitude of the location. Separated by comma.
CamelGeoCoderCity The city long name.
CamelGeoCoderRegionCode The region code.
CamelGeoCoderRegionName The region name.
CamelGeoCoderCountryLong The country long name.
CamelGeoCoderCountryShort The country short name.
Notice not all headers may be provided depending on available data and mode in use (address vs latlng).

Samples

In the example below we get the latitude and longitude for Paris, France
  from("direct:start")
    .to("geocoder:address:Paris, France")
If you provide a header with the CamelGeoCoderAddress then that overrides the endpoint configuration, so to get the location of Copenhagen, Denmark we can send a message with a headers as shown:
template.sendBodyAndHeader("direct:start", "Hello", GeoCoderConstants.ADDRESS, "Copenhagen, Denmark");
To get the address for a latitude and longitude we can do:
  from("direct:start")
    .to("geocoder:latlng:40.714224,-73.961452")
    .log("Location ${header.CamelGeocoderAddress} is at lat/lng: ${header.CamelGeocoderLatlng} and in country ${header.CamelGeoCoderCountryShort}")
Which will log
Location 285 Bedford Avenue, Brooklyn, NY 11211, USA is at lat/lng: 40.71412890,-73.96140740 and in country US
To get the current location you can use "current" as the address as shown:
  from("direct:start")
    .to("geocoder:address:current")

Chapter 43. Guava EventBus

Guava EventBus Component

Available since Camel 2.10.0
The Google Guava EventBus allows publish-subscribe-style communication between components without requiring the components to explicitly register with one another (and thus be aware of each other). The guava-eventbus: component provides integration bridge between Camel and Google Guava EventBus infrastructure. With the latter component, messages exchanged with the Guava EventBus can be transparently forwarded to the Camel routes. EventBus component allows also to route body of Camel exchanges to the Guava EventBus.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-guava-eventbus</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

guava-eventbus:busName[?options]
Where busName represents the name of the com.google.common.eventbus.EventBus instance located in the Camel registry.

Options

Name Default Value Description
eventClass null Camel 2.10: If used on the consumer side of the route, will filter events received from the EventBus to the instances of the class and superclasses of eventClass. Null value of this option is equal to setting it to the java.lang.Object i.e. the consumer will capture all messages incoming to the event bus. This option cannot be used together with listenerInterface option.
listenerInterface null Camel 2.11: The interface with method(s) marked with the @Subscribe annotation. Dynamic proxy will be created over the interface so it could be registered as the EventBus listener. Particularly useful when creating multi-event listeners and for handling DeadEvent properly. This option cannot be used together with eventClass option.

Usage

Using guava-eventbus component on the consumer side of the route will capture messages sent to the Guava EventBus and forward them to the Camel route. Guava EventBus consumer processes incoming messages asynchronously.
SimpleRegistry registry = new SimpleRegistry();
EventBus eventBus = new EventBus();
registry.put("busName", eventBus);
CamelContext camel = new DefaultCamelContext(registry);

from("guava-eventbus:busName").to("seda:queue");

eventBus.post("Send me to the SEDA queue.");
Using guava-eventbus component on the producer side of the route will forward body of the Camel exchanges to the Guava EventBus instance.
SimpleRegistry registry = new SimpleRegistry();
EventBus eventBus = new EventBus();
registry.put("busName", eventBus);
CamelContext camel = new DefaultCamelContext(registry);

from("direct:start").to("guava-eventbus:busName");

ProducerTemplate producerTemplate = camel.createProducerTemplate();
producer.sendBody("direct:start", "Send me to the Guava EventBus.");

eventBus.register(new Object(){
  @Subscribe
  public void messageHander(String message) {
    System.out.println("Message received from the Camel: " + message);
  }
});

DeadEvent considerations

Keep in mind that due to the limitations caused by the design of the Guava EventBus, you cannot specify event class to be received by the listener without creating class annotated with @Subscribe method. This limitation implies that endpoint with eventClass option specified actually listens to all possible events (java.lang.Object) and filter appropriate messages programmatically at runtime. The snipped below demonstrates an appropriate excerpt from the Camel code base.
@Subscribe
public void eventReceived(Object event) {
  if (eventClass == null || eventClass.isAssignableFrom(event.getClass())) {
    doEventReceived(event);
...
This drawback of this approach is that EventBus instance used by Camel will never generate com.google.common.eventbus.DeadEvent notifications. If you want Camel to listen only to the precisely specified event (and therefore enable DeadEvent support), use listenerInterface endpoint option. Camel will create dynamic proxy over the interface you specify with the latter option and listen only to messages specified by the interface handler methods. The example of the listener interface with single method handling only SpecificEvent instances is demonstrated below.
package com.example;

public interface CustomListener {

  @Subscribe
  void eventReceived(SpecificEvent event);

}
The listener presented above could be used in the endpoint definition as follows.
from("guava-eventbus:busName?listenerInterface=com.example.CustomListener").to("seda:queue");

Consuming multiple type of events

In order to define multiple type of events to be consumed by Guava EventBus consumer use listenerInterface endpoint option, as listener interface could provide multiple methods marked with the @Subscribe annotation.
package com.example;

public interface MultipleEventsListener {

  @Subscribe
  void someEventReceived(SomeEvent event);

  @Subscribe
  void anotherEventReceived(AnotherEvent event);

}
The listener presented above could be used in the endpoint definition as follows.
from("guava-eventbus:busName?listenerInterface=com.example.MultipleEventsListener").to("seda:queue");

Chapter 44. HawtDB

HawtDB

Available as of Apache Camel 2.3
HawtDB is a very lightweight and embeddable key value database. It allows together with Apache Camel to provide persistent support for various Apache Camel features such as section "Aggregator" in "Apache Camel Development Guide".

Deprecated

The HawtDB project is being deprecated and replaced by leveldb as the lightweight and embedable key value database. To make using leveldb easy there is a leveldbjni project for that. The Apache ActiveMQ project is planning on using leveldb as their primary file based message store in the future, to replace kahadb.
There os a camel-leveldb component we recommend to use instead of this.
Current features it provides:
  • HawtDBAggregationRepository

Using HawtDBAggregationRepository

HawtDBAggregationRepository is an AggregationRepository which on the fly persists the aggregated messages. This ensures that you will not loose messages, as the default aggregator will use an in memory only AggregationRepository.
It has the following options:
Option Type Description
repositoryName String A mandatory repository name. Allows you to use a shared HawtDBFile for multiple repositories.
persistentFileName String Filename for the persistent storage. If no file exists on startup a new file is created.
bufferSize int The size of the memory segment buffer which is mapped to the file store. By default its 8mb. The value is in bytes.
sync boolean Whether or not the HawtDBFile should sync on write or not. Default is true. By sync on write ensures that its always waiting for all writes to be spooled to disk and thus will not loose updates. If you disable this option, then HawtDB will auto sync when it has batched up a number of writes.
pageSize short The size of memory pages. By default its 512 bytes. The value is in bytes.
hawtDBFile HawtDBFile Use an existing configured org.apache.camel.component.hawtdb.HawtDBFile instance.
returnOldExchange boolean Whether the get operation should return the old existing Exchange if any existed. By default this option is false to optimize as we do not need the old exchange when aggregating.
useRecovery boolean Whether or not recovery is enabled. This option is by default true. When enabled the Apache Camel section "Aggregator" in "Apache Camel Development Guide" automatic recover failed aggregated exchange and have them resubmitted.
recoveryInterval long If recovery is enabled then a background task is run every x'th time to scan for failed exchanges to recover and resubmit. By default this interval is 5000 millis.
maximumRedeliveries int Allows you to limit the maximum number of redelivery attempts for a recovered exchange. If enabled then the Exchange will be moved to the dead letter channel if all redelivery attempts failed. By default this option is disabled. If this option is used then the deadLetterUri option must also be provided.
deadLetterUri String An endpoint uri for a Dead Letter Channel where exhausted recovered Exchanges will be moved. If this option is used then the maximumRedeliveries option must also be provided.
optimisticLocking false Camel 2.12: To turn on optimistic locking, which often would be needed in clustered environments where multiple Camel applications shared the same HawtDB based aggregation repository.
The repositoryName option must be provided. Then either the persistentFileName or the hawtDBFile must be provided.

What is preserved when persisting

HawtDBAggregationRepository will only preserve any Serializable compatible data types. If a data type is not such a type its dropped and a WARN is logged. And it only persists the Message body and the Message headers. The Exchange properties are not persisted.

Recovery

The HawtDBAggregationRepository will by default recover any failed Exchange. It does this by having a background tasks that scans for failed Exchanges in the persistent store. You can use the checkInterval option to set how often this task runs. The recovery works as transactional which ensures that Apache Camel will try to recover and redeliver the failed Exchange. Any Exchange which was found to be recovered will be restored from the persistent store and resubmitted and send out again.
The following headers is set when an Exchange is being recovered/redelivered:
Header Type Description
Exchange.REDELIVERED Boolean Is set to true to indicate the Exchange is being redelivered.
Exchange.REDELIVERY_COUNTER Integer The redelivery attempt, starting from 1.
Only when an Exchange has been successfully processed it will be marked as complete which happens when the confirm method is invoked on the AggregationRepository. This means if the same Exchange fails again it will be kept retried until it success.
You can use option maximumRedeliveries to limit the maximum number of redelivery attempts for a given recovered Exchange. You must also set the deadLetterUri option so Apache Camel knows where to send the Exchange when the maximumRedeliveries was hit.
You can see some examples in the unit tests of camel-hawtdb, for example this test.

Using HawtDBAggregationRepository in Java DSL

In this example we want to persist aggregated messages in the target/data/hawtdb.dat file.
public void configure() throws Exception {
    // create the hawtdb repo
    HawtDBAggregationRepository repo = new HawtDBAggregationRepository("repo1", "target/data/hawtdb.dat");

    // here is the Camel route where we aggregate
    from("direct:start")
        .aggregate(header("id"), new MyAggregationStrategy())
            // use our created hawtdb repo as aggregation repository
            .completionSize(5).aggregationRepository(repo)
            .to("mock:aggregated");
}

Using HawtDBAggregationRepository in Spring XML

The same example but using Spring XML instead:
<!-- a persistent aggregation repository using camel-hawtdb -->
<bean id="repo" class="org.apache.camel.component.hawtdb.HawtDBAggregationRepository">
    <!-- store the repo in the hawtdb.dat file -->
    <property name="persistentFileName" value="target/data/hawtdb.dat"/>
    <!-- and use repo2 as the repository name -->
    <property name="repositoryName" value="repo2"/>
</bean>

<!-- aggregate the messages using this strategy -->
<bean id="myAggregatorStrategy" class="org.apache.camel.component.hawtdb.HawtDBSpringAggregateTest$MyAggregationStrategy"/>

<!-- this is the camel routes -->
<camelContext id="camel" xmlns="http://camel.apache.org/schema/spring">

    <route>
        <from uri="direct:start"/>
        <!-- aggregate using our strategy and hawtdb repo, and complete when we have 5 messages aggregated -->
        <aggregate strategyRef="myAggregatorStrategy" aggregationRepositoryRef="repo" completionSize="5">
            <!-- correlate by header with the key id -->
            <correlationExpression><header>id</header></correlationExpression>
            <!-- send aggregated messages to the mock endpoint -->
            <to uri="mock:aggregated"/>
        </aggregate>
    </route>

</camelContext>

Dependencies

To use HawtDB in your Apache Camel routes you need to add the a dependency on camel-hawtdb.
If you use maven you could just add the following to your pom.xml, substituting the version number for the latest & greatest release (see the download page for the latest versions).
<dependency>
  <groupId>org.apache.camel</groupId>
  <artifactId>camel-hawtdb</artifactId>
  <version>2.3.0</version>
</dependency>
See Also:

Chapter 45. Hazelcast Component

Hazelcast Component

Available as of Apache Camel 2.7
The hazelcast: component allows you to work with the Hazelcast distributed data grid / cache. Hazelcast is a in memory data grid, entirely written in Java (single jar). It offers a great palette of different data stores like map, multi map (same key, n values), queue, list and atomic number. The main reason to use Hazelcast is its simple cluster support. If you have enabled multicast on your network you can run a cluster with hundred nodes with no extra configuration. Hazelcast can simply configured to add additional features like n copies between nodes (default is 1), cache persistence, network configuration (if needed), near cache, enviction and so on. For more information consult the Hazelcast documentation on http://www.hazelcast.com/docs.jsp.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-hazelcast</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

hazelcast:[ map | multimap | queue | seda | set | atomicvalue | instance]:cachename[?options]

Warning

You have to use the second prefix to define which type of data store you want to use.

Sections

  1. Usage of #map
  2. Usage of #multimap
  3. Usage of #queue
  4. Usage of #list
  5. Usage of #seda
  6. Usage of atomic number
  7. Usage of #cluster support (instance)

Usage of Map

map cache producer - to("hazelcast:map:foo")

If you want to store a value in a map you can use the map cache producer. The map cache producer provides 5 operations (put, get, update, delete, query). For the first 4 you have to provide the operation inside the "hazelcast.operation.type" header variable. In Java DSL you can use the constants from org.apache.camel.component.hazelcast.HazelcastConstants.
Header Variables for the request message:
Name Type Description
hazelcast.operation.type String valid values are: put, delete, get, update, query
hazelcast.objectId String the object id to store / find your object inside the cache (not needed for the query operation)

Warning

Header variables have changed in Apache Camel 2.8
Name Type Description
CamelHazelcastOperationType String valid values are: put, delete, get, update, query Version 2.8
CamelHazelcastObjectId String the object id to store / find your object inside the cache (not needed for the query operation) Version 2.8
You can call the samples with:
template.sendBodyAndHeader("direct:[put|get|update|delete|query]", "my-foo", HazelcastConstants.OBJECT_ID, "4711");

Sample for put:

Java DSL:
from("direct:put")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.PUT_OPERATION))
.toF("hazelcast:%sfoo", HazelcastConstants.MAP_PREFIX);
Spring DSL:
<route>
	<from uri="direct:put" />
        <!-- If using version 2.8 and above set headerName to "CamelHazelcastOperationType" -->
	<setHeader headerName="hazelcast.operation.type">
		<constant>put</constant>
	</setHeader>
	<to uri="hazelcast:map:foo" />
</route>

Sample for get:

Java DSL:
from("direct:get")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.GET_OPERATION))
.toF("hazelcast:%sfoo", HazelcastConstants.MAP_PREFIX)
.to("seda:out");
Spring DSL:
<route>
	<from uri="direct:get" />
        <!-- If using version 2.8 and above set headerName to "CamelHazelcastOperationType" -->
	<setHeader headerName="hazelcast.operation.type">
		<constant>get</constant>
	</setHeader>
	<to uri="hazelcast:map:foo" />
	<to uri="seda:out" />
</route>

Sample for update:

Java DSL:
from("direct:update")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.UPDATE_OPERATION))
.toF("hazelcast:%sfoo", HazelcastConstants.MAP_PREFIX);
Spring DSL:
<route>
	<from uri="direct:update" />
        <!-- If using version 2.8 and above set headerName to "CamelHazelcastOperationType" -->
	<setHeader headerName="hazelcast.operation.type">
		<constant>update</constant>
	</setHeader>
	<to uri="hazelcast:map:foo" />
</route>

Sample for delete:

Java DSL:
from("direct:delete")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.DELETE_OPERATION))
.toF("hazelcast:%sfoo", HazelcastConstants.MAP_PREFIX);
Spring DSL:
<route>
	<from uri="direct:delete" />
        <!-- If using version 2.8 and above set headerName to "CamelHazelcastOperationType" -->
	<setHeader headerName="hazelcast.operation.type">
		<constant>delete</constant>
	</setHeader>
	<to uri="hazelcast:map:foo" />
</route>

Sample for query

Java DSL:
from("direct:query")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.QUERY_OPERATION))
.toF("hazelcast:%sfoo", HazelcastConstants.MAP_PREFIX)
.to("seda:out");
Spring DSL:
<route>
	<from uri="direct:query" />
        <!-- If using version 2.8 and above set headerName to "CamelHazelcastOperationType" -->
	<setHeader headerName="hazelcast.operation.type">
		<constant>query</constant>
	</setHeader>
	<to uri="hazelcast:map:foo" />
	<to uri="seda:out" />
</route>
For the query operation Hazelcast offers a SQL like syntax to query your distributed map.
String q1 = "bar > 1000";
template.sendBodyAndHeader("direct:query", null, HazelcastConstants.QUERY, q1);

map cache consumer - from("hazelcast:map:foo")

Hazelcast provides event listeners on their data grid. If you want to be notified if a cache will be manipulated, you can use the map consumer. There're 4 events: put, update, delete and envict. The event type will be stored in the "hazelcast.listener.action" header variable. The map consumer provides some additional information inside these variables:
Header Variables inside the response message:
Name Type Description
hazelcast.listener.time Long time of the event in millis
hazelcast.listener.type String the map consumer sets here "cachelistener"
hazelcast.listener.action String type of event - here added, updated, envicted and removed
hazelcast.objectId String the oid of the object
hazelcast.cache.name String the name of the cache - e.g. "foo"
hazelcast.cache.type String the type of the cache - here map

Warning

Header variables have changed in Apache Camel 2.8
Name Type Description
CamelHazelcastListenerTime Long time of the event in millis Version 2.8
CamelHazelcastListenerType String the map consumer sets here "cachelistener" Version 2.8
CamelHazelcastListenerAction String type of event - here added, updated, envicted and removed. Version 2.8
CamelHazelcastObjectId String the oid of the object Version 2.8
CamelHazelcastCacheName String the name of the cache - e.g. "foo" Version 2.8
CamelHazelcastCacheType String the type of the cache - here map Version 2.8
The object value will be stored within put and update actions inside the message body.
Here's a sample:
fromF("hazelcast:%sfoo", HazelcastConstants.MAP_PREFIX)
.log("object...")
.choice()
    .when(header(HazelcastConstants.LISTENER_ACTION).isEqualTo(HazelcastConstants.ADDED))
         .log("...added")
         .to("mock:added")
    .when(header(HazelcastConstants.LISTENER_ACTION).isEqualTo(HazelcastConstants.ENVICTED))
         .log("...envicted")
         .to("mock:envicted")
    .when(header(HazelcastConstants.LISTENER_ACTION).isEqualTo(HazelcastConstants.UPDATED))
         .log("...updated")
         .to("mock:updated")
    .when(header(HazelcastConstants.LISTENER_ACTION).isEqualTo(HazelcastConstants.REMOVED))
         .log("...removed")
         .to("mock:removed")
    .otherwise()
         .log("fail!");

Usage of Multi Map

multimap cache producer - to("hazelcast:multimap:foo")

A multimap is a cache where you can store n values to one key. The multimap producer provides 4 operations (put, get, removevalue, delete).
Header Variables for the request message:
Name Type Description
hazelcast.operation.type String valid values are: put, get, removevalue, delete
hazelcast.objectId String the object id to store / find your object inside the cache

Warning

Header variables have changed in Apache Camel 2.8
Header Variables for the request message in Apache Camel 2.8:
Name Type Description
CamelHazelcastOperationType String valid values are: put, delete, get, update, query Available as of Apache Camel 2.8
CamelHazelcastObjectId String the object id to store / find your object inside the cache (not needed for the query operation) Version 2.8
You can call the samples with:
template.sendBodyAndHeader("direct:[put|get|update|delete|query]", "my-foo", HazelcastConstants.OBJECT_ID, "4711");

Sample for put:

Java DSL:
from("direct:put")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.PUT_OPERATION))
.toF("hazelcast:%sfoo", HazelcastConstants.MAP_PREFIX);
Spring DSL:
<route>
	<from uri="direct:put" />
        <!-- If using version 2.8 and above set headerName to "CamelHazelcastOperationType" -->
	<setHeader headerName="hazelcast.operation.type">
		<constant>put</constant>
	</setHeader>
	<to uri="hazelcast:map:foo" />
</route>

Sample for get:

Java DSL:
from("direct:get")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.GET_OPERATION))
.toF("hazelcast:%sfoo", HazelcastConstants.MAP_PREFIX)
.to("seda:out");
Spring DSL:
<route>
	<from uri="direct:get" />
        <!-- If using version 2.8 and above set headerName to "CamelHazelcastOperationType" -->
	<setHeader headerName="hazelcast.operation.type">
		<constant>get</constant>
	</setHeader>
	<to uri="hazelcast:map:foo" />
	<to uri="seda:out" />
</route>

Sample for update:

Java DSL:
from("direct:update")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.UPDATE_OPERATION))
.toF("hazelcast:%sfoo", HazelcastConstants.MAP_PREFIX);
Spring DSL:
<route>
	<from uri="direct:update" />
        <!-- If using version 2.8 and above set headerName to "CamelHazelcastOperationType" -->
	<setHeader headerName="hazelcast.operation.type">
		<constant>update</constant>
	</setHeader>
	<to uri="hazelcast:map:foo" />
</route>

Sample for delete:

Java DSL:
from("direct:delete")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.DELETE_OPERATION))
.toF("hazelcast:%sfoo", HazelcastConstants.MAP_PREFIX);
Spring DSL:
<route>
	<from uri="direct:delete" />
        <!-- If using version 2.8 and above set headerName to "CamelHazelcastOperationType" -->
	<setHeader headerName="hazelcast.operation.type">
		<constant>delete</constant>
	</setHeader>
	<to uri="hazelcast:map:foo" />
</route>

Sample for query

Java DSL:
from("direct:query")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.QUERY_OPERATION))
.toF("hazelcast:%sfoo", HazelcastConstants.MAP_PREFIX)
.to("seda:out");
Spring DSL:
<route>
	<from uri="direct:query" />
        <!-- If using version 2.8 and above set headerName to "CamelHazelcastOperationType" -->
	<setHeader headerName="hazelcast.operation.type">
		<constant>query</constant>
	</setHeader>
	<to uri="hazelcast:map:foo" />
	<to uri="seda:out" />
</route>
For the query operation Hazelcast offers a SQL like syntax to query your distributed map.
String q1 = "bar > 1000";
template.sendBodyAndHeader("direct:query", null, HazelcastConstants.QUERY, q1);

map cache consumer - from("hazelcast:map:foo")

Hazelcast provides event listeners on their data grid. If you want to be notified if a cache will be manipulated, you can use the map consumer. There're 4 events: put, update, delete and envict. The event type will be stored in the "hazelcast.listener.action" header variable. The map consumer provides some additional information inside these variables:
Header Variables inside the response message:
Name Type Description
hazelcast.listener.time Long time of the event in millis
hazelcast.listener.type String the map consumer sets here "cachelistener"
hazelcast.listener.action String type of event - here added, updated, envicted and removed
hazelcast.objectId String the oid of the object
hazelcast.cache.name String the name of the cache - e.g. "foo"
hazelcast.cache.type String the type of the cache - here map

Warning

Header variables have changed in Apache Camel 2.8
Name Type Description
CamelHazelcastListenerTime Long time of the event in millis Version 2.8
CamelHazelcastListenerType String the map consumer sets here "cachelistener" Version 2.8
CamelHazelcastListenerAction String type of event - here added, updated, envicted and removed. Version 2.8
CamelHazelcastObjectId String the oid of the object Version 2.8
CamelHazelcastCacheName String the name of the cache - e.g. "foo" Version 2.8
CamelHazelcastCacheType String the type of the cache - here map Version 2.8
The object value will be stored within put and update actions inside the message body.
Here's a sample:
fromF("hazelcast:%sfoo", HazelcastConstants.MAP_PREFIX)
.log("object...")
.choice()
    .when(header(HazelcastConstants.LISTENER_ACTION).isEqualTo(HazelcastConstants.ADDED))
         .log("...added")
         .to("mock:added")
    .when(header(HazelcastConstants.LISTENER_ACTION).isEqualTo(HazelcastConstants.ENVICTED))
         .log("...envicted")
         .to("mock:envicted")
    .when(header(HazelcastConstants.LISTENER_ACTION).isEqualTo(HazelcastConstants.UPDATED))
         .log("...updated")
         .to("mock:updated")
    .when(header(HazelcastConstants.LISTENER_ACTION).isEqualTo(HazelcastConstants.REMOVED))
         .log("...removed")
         .to("mock:removed")
    .otherwise()
         .log("fail!");

Usage of Multi Map

multimap cache producer - to("hazelcast:multimap:foo")

A multimap is a cache where you can store n values to one key. The multimap producer provides 4 operations (put, get, removevalue, delete).
Header Variables for the request message:
Name Type Description
hazelcast.operation.type String valid values are: put, get, removevalue, delete
hazelcast.objectId String the object id to store / find your object inside the cache

Warning

Header variables have changed in Apache Camel 2.8
Name Type Description
CamelHazelcastOperationType String valid values are: put, get, removevalue, delete Version 2.8
CamelHazelcastObjectId String the object id to store / find your object inside the cache Version 2.8

Sample for put:

Java DSL:
from("direct:put")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.PUT_OPERATION))
.to(String.format("hazelcast:%sbar", HazelcastConstants.MULTIMAP_PREFIX));
Spring DSL:
<route>
	<from uri="direct:put" />
	<log message="put.."/>
        <!-- If using version 2.8 and above set headerName to "CamelHazelcastOperationType" -->
	<setHeader headerName="hazelcast.operation.type">
		<constant>put</constant>
	</setHeader>
	<to uri="hazelcast:multimap:foo" />
</route>

Sample for removevalue:

Java DSL:
from("direct:removevalue")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.REMOVEVALUE_OPERATION))
.toF("hazelcast:%sbar", HazelcastConstants.MULTIMAP_PREFIX);
Spring DSL:
<route>
	<from uri="direct:removevalue" />
	<log message="removevalue..."/>
        <!-- If using version 2.8 and above set headerName to "CamelHazelcastOperationType" -->
	<setHeader headerName="hazelcast.operation.type">
		<constant>removevalue</constant>
	</setHeader>
	<to uri="hazelcast:multimap:foo" />
</route>
To remove a value you have to provide the value you want to remove inside the message body. If you have a multimap object } you have to put "my-foo" inside the message body to remove the "my-foo" value.

Sample for get:

Java DSL:
from("direct:get")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.GET_OPERATION))
.toF("hazelcast:%sbar", HazelcastConstants.MULTIMAP_PREFIX)
.to("seda:out");
Spring DSL:
<route>
	<from uri="direct:get" />
	<log message="get.."/>
        <!-- If using version 2.8 and above set headerName to "CamelHazelcastOperationType" -->
	<setHeader headerName="hazelcast.operation.type">
		<constant>get</constant>
	</setHeader>
	<to uri="hazelcast:multimap:foo" />
	<to uri="seda:out" />
</route>

Sample for delete:

Java DSL:
from("direct:delete")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.DELETE_OPERATION))
.toF("hazelcast:%sbar", HazelcastConstants.MULTIMAP_PREFIX);
Spring DSL:
<route>
	<from uri="direct:delete" />
	<log message="delete.."/>
        <!-- If using version 2.8 and above set headerName to "CamelHazelcastOperationType" -->
	<setHeader headerName="hazelcast.operation.type">
		<constant>delete</constant>
	</setHeader>
	<to uri="hazelcast:multimap:foo" />
</route>
you can call them in your test class with:
template.sendBodyAndHeader("direct:[put|get|removevalue|delete]", "my-foo", HazelcastConstants.OBJECT_ID, "4711");

multimap cache consumer - from("hazelcast:multimap:foo")

For the multimap cache this component provides the same listeners / variables as for the map cache consumer (except the update and enviction listener). The only difference is the multimap prefix inside the URI. Here is a sample:
fromF("hazelcast:%sbar", HazelcastConstants.MULTIMAP_PREFIX)
.log("object...")
.choice()
	.when(header(HazelcastConstants.LISTENER_ACTION).isEqualTo(HazelcastConstants.ADDED))
		.log("...added")
                .to("mock:added")
        //.when(header(HazelcastConstants.LISTENER_ACTION).isEqualTo(HazelcastConstants.ENVICTED))
        //        .log("...envicted")
        //        .to("mock:envicted")
        .when(header(HazelcastConstants.LISTENER_ACTION).isEqualTo(HazelcastConstants.REMOVED))
                .log("...removed")
                .to("mock:removed")
        .otherwise()
                .log("fail!");
Header Variables inside the response message:
Name Type Description
hazelcast.listener.time Long time of the event in millis
hazelcast.listener.type String the map consumer sets here "cachelistener"
hazelcast.listener.action String type of event - here added and removed (and soon envicted)
hazelcast.objectId String the oid of the object
hazelcast.cache.name String the name of the cache - e.g. "foo"
hazelcast.cache.type String the type of the cache - here multimap
Eviction will be added as feature, soon (this is a Hazelcast issue).

Warning

Header variables have changed in Apache Camel 2.8
Name Type Description
CamelHazelcastListenerTime Long time of the event in millis Version 2.8
CamelHazelcastListenerType String the map consumer sets here "cachelistener" Version 2.8
CamelHazelcastListenerAction String type of event - here added and removed (and soon envicted) Version 2.8
CamelHazelcastObjectId String the oid of the object Version 2.8
CamelHazelcastCacheName String the name of the cache - e.g. "foo" Version 2.8
CamelHazelcastCacheType String the type of the cache - here multimap Version 2.8

Usage of Queue

Queue producer – to("hazelcast:queue:foo")

The queue producer provides 6 operations (add, put, poll, peek, offer, removevalue).

Sample for add:

from("direct:add")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.ADD_OPERATION))
.toF("hazelcast:%sbar", HazelcastConstants.QUEUE_PREFIX);

Sample for put:

from("direct:put")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.PUT_OPERATION))
.toF("hazelcast:%sbar", HazelcastConstants.QUEUE_PREFIX);

Sample for poll:

from("direct:poll")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.POLL_OPERATION))
.toF("hazelcast:%sbar", HazelcastConstants.QUEUE_PREFIX);

Sample for peek:

from("direct:peek")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.PEEK_OPERATION))
.toF("hazelcast:%sbar", HazelcastConstants.QUEUE_PREFIX);

Sample for offer:

from("direct:offer")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.OFFER_OPERATION))
.toF("hazelcast:%sbar", HazelcastConstants.QUEUE_PREFIX);

Sample for removevalue:

from("direct:removevalue")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.REMOVEVALUE_OPERATION))
.toF("hazelcast:%sbar", HazelcastConstants.QUEUE_PREFIX);

Queue consumer – from("hazelcast:queue:foo")

The queue consumer provides 2 operations (add, remove).
fromF("hazelcast:%smm", HazelcastConstants.QUEUE_PREFIX)
   .log("object...")
   .choice()
	.when(header(HazelcastConstants.LISTENER_ACTION).isEqualTo(HazelcastConstants.ADDED))
        	.log("...added")
		.to("mock:added")
	.when(header(HazelcastConstants.LISTENER_ACTION).isEqualTo(HazelcastConstants.REMOVED))
		.log("...removed")
		.to("mock:removed")
	.otherwise()
		.log("fail!");

Usage of List

List producer – to("hazelcast:list:foo")

The list producer provides 4 operations (add, set, get, removevalue).

Sample for add:

from("direct:add")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.ADD_OPERATION))
.toF("hazelcast:%sbar", HazelcastConstants.LIST_PREFIX);

Sample for get:

from("direct:get")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.GET_OPERATION))
.toF("hazelcast:%sbar", HazelcastConstants.LIST_PREFIX)
.to("seda:out");

Sample for setvalue:

from("direct:set")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.SETVALUE_OPERATION))
.toF("hazelcast:%sbar", HazelcastConstants.LIST_PREFIX);

Sample for removevalue:

from("direct:removevalue")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.REMOVEVALUE_OPERATION))
.toF("hazelcast:%sbar", HazelcastConstants.LIST_PREFIX);

Warning

Please note that set,get and removevalue and not yet supported by hazelcast, will be added in the future..

List consumer – from("hazelcast:list:foo")

The list consumer provides 2 operations (add, remove).
fromF("hazelcast:%smm", HazelcastConstants.LIST_PREFIX)
	.log("object...")
	.choice()
		.when(header(HazelcastConstants.LISTENER_ACTION).isEqualTo(HazelcastConstants.ADDED))
			.log("...added")
                        .to("mock:added")
		.when(header(HazelcastConstants.LISTENER_ACTION).isEqualTo(HazelcastConstants.REMOVED))
			.log("...removed")
                        .to("mock:removed")
                .otherwise()
                        .log("fail!");

Usage of SEDA

SEDA component differs from the rest components provided. It implements a work-queue in order to support asynchronous SEDA architectures, similar to the core "SEDA" component.

SEDA producer – to("hazelcast:seda:foo")

The SEDA producer provides no operations. You only send data to the specified queue.
Name default value Description
transferExchange false Apache Camel 2.8.0: if set to true the whole Exchange will be transfered. If header or body contains not serializable objects, they will be skipped.
Java DSL :
from("direct:foo")
.to("hazelcast:seda:foo");
Spring DSL :
<route>
   <from uri="direct:start" />
   <to uri="hazelcast:seda:foo" />
</route>

SEDA consumer – from("hazelcast:seda:foo")

The SEDA consumer provides no operations. You only retrieve data from the specified queue.
Name default value Description
pollInterval 1000 How frequent to poll from the SEDA queue
concurrentConsumers 1 To use concurrent consumers polling from the SEDA queue.
transferExchange false Camel 2.8.0: if set to true the whole Exchange will be transfered. If header or body contains not serializable objects, they will be skipped.
transacted false Camel 2.10.4: if set to true then the consumer runs in transaction mode, where the messages in the seda queue will only be removed if the transaction commits, which happens when the processing is complete.
Java DSL :
from("hazelcast:seda:foo")
.to("mock:result");
Spring DSL:
<route>
  <from uri="hazelcast:seda:foo" />
  <to uri="mock:result" />
</route>

Usage of Atomic Number

Warning

There is no consumer for this endpoint\!

atomic number producer - to("hazelcast:atomicnumber:foo")

An atomic number is an object that simply provides a grid wide number (long). The operations for this producer are setvalue (set the number with a given value), get, increase (+1), decrease (-1) and destroy.
Header Variables for the request message:
Name Type Description
hazelcast.operation.type String valid values are: setvalue, get, increase, decrease, destroy

Warning

Header variables have changed in Apache Camel 2.8
Name Type Description
CamelHazelcastOperationType String valid values are: setvalue, get, increase, decrease, destroy Available as of Apache Camel version 2.8

Sample for set:

Java DSL:
from("direct:set")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.SETVALUE_OPERATION))
.toF("hazelcast:%sfoo", HazelcastConstants.ATOMICNUMBER_PREFIX);
Spring DSL:
<route>
	<from uri="direct:set" />
        <!-- If using version 2.8 and above set headerName to "CamelHazelcastOperationType" -->
	<setHeader headerName="hazelcast.operation.type">
		<constant>setvalue</constant>
	</setHeader>
	<to uri="hazelcast:atomicvalue:foo" />
</route>
Provide the value to set inside the message body (here the value is 10): template.sendBody("direct:set", 10);

Sample for get:

Java DSL:
from("direct:get")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.GET_OPERATION))
.toF("hazelcast:%sfoo", HazelcastConstants.ATOMICNUMBER_PREFIX);
Spring DSL:
<route>
	<from uri="direct:get" />
        <!-- If using version 2.8 and above set headerName to "CamelHazelcastOperationType" -->
	<setHeader headerName="hazelcast.operation.type">
		<constant>get</constant>
	</setHeader>
	<to uri="hazelcast:atomicvalue:foo" />
</route>
You can get the number with long body = template.requestBody("direct:get", null, Long.class);.

Sample for increment:

Java DSL:
from("direct:increment")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.INCREMENT_OPERATION))
.toF("hazelcast:%sfoo", HazelcastConstants.ATOMICNUMBER_PREFIX);
Spring DSL:
<route>
	<from uri="direct:increment" />
        <!-- If using version 2.8 and above set headerName to "CamelHazelcastOperationType" -->
	<setHeader headerName="hazelcast.operation.type">
		<constant>increment</constant>
	</setHeader>
	<to uri="hazelcast:atomicvalue:foo" />
</route>
The actual value (after increment) will be provided inside the message body.

Sample for decrement:

Java DSL:
from("direct:decrement")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.DECREMENT_OPERATION))
.toF("hazelcast:%sfoo", HazelcastConstants.ATOMICNUMBER_PREFIX);
Spring DSL:
<route>
	<from uri="direct:decrement" />
        <!-- If using version 2.8 and above set headerName to "CamelHazelcastOperationType" -->
	<setHeader headerName="hazelcast.operation.type">
		<constant>decrement</constant>
	</setHeader>
	<to uri="hazelcast:atomicvalue:foo" />
</route>
The actual value (after decrement) will be provided inside the message body.

Sample for destroy

Warning

There's a bug inside Hazelcast. So this feature may not work properly. Will be fixed in 1.9.3.
Java DSL:
from("direct:destroy")
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.DESTROY_OPERATION))
.toF("hazelcast:%sfoo", HazelcastConstants.ATOMICNUMBER_PREFIX);
Spring DSL:
<route>
	<from uri="direct:destroy" />
        <!-- If using version 2.8 and above set headerName to "CamelHazelcastOperationType" -->
	<setHeader headerName="hazelcast.operation.type">
		<constant>destroy</constant>
	</setHeader>
	<to uri="hazelcast:atomicvalue:foo" />
</route>

cluster support

Warning

This endpoint provides no producer\!

instance consumer - from("hazelcast:instance:foo")

Hazelcast makes sense in one single "server node", but it's extremly powerful in a clustered environment. The instance consumer fires if a new cache instance will join or leave the cluster.
Here's a sample:
fromF("hazelcast:%sfoo", HazelcastConstants.INSTANCE_PREFIX)
.log("instance...")
.choice()
	.when(header(HazelcastConstants.LISTENER_ACTION).isEqualTo(HazelcastConstants.ADDED))
		.log("...added")
		.to("mock:added")
	.otherwise()
		.log("...removed")
		.to("mock:removed");
Each event provides the following information inside the message header:
Header Variables inside the response message:
Name Type Description
hazelcast.listener.time Long time of the event in millis
hazelcast.listener.type String the map consumer sets here "instancelistener"
hazelcast.listener.action String type of event - here added or removed
hazelcast.instance.host String host name of the instance
hazelcast.instance.port Integer port number of the instance

Warning

Header variables have changed in Apache Camel 2.8
Name Type Description
CamelHazelcastListenerTime Long time of the event in millis Version 2.8
CamelHazelcastListenerType String the map consumer sets here "instancelistener" Version 2.8
CamelHazelcastListenerActionn String type of event - here added or removed. Version 2.8
CamelHazelcastInstanceHost String host name of the instance Version 2.8
CamelHazelcastInstancePort Integer port number of the instance Version 2.8

Chapter 46. hbase

HBase Component

Available as of Camel 2.10
This component provides an idemptotent repository, producers and consumers for Apache HBase.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-hbase</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

Apache HBase Overview

HBase is an open-source, distributed, versioned, column-oriented store modeled after Google's Bigtable: A Distributed Storage System for Structured Data. You can use HBase when you need random, realtime read/write access to your Big Data. More information at Apache HBase.

Camel and HBase

When using a datasotre inside a camel route, there is always the chalenge of specifying how the camel message will stored to the datastore. In document based stores things are more easy as the message body can be directly mapped to a document. In relational databases an ORM solution can be used to map properties to columns etc. In column based stores things are more challenging as there is no standard way to perform that kind of mapping.
HBase adds two additional challenges:
  • HBase groups columns into families, so just mapping a property to a column using a name convention is just not enough.
  • HBase doesn't have the notion of type, which means that it stores everything as byte[] and doesn't know if the byte[] represents a String, a Number, a serialized Java object or just binary data.
To overcome these challenges, camel-hbase makes use of the message headers to specify the mapping of the message to HBase columns. It also provides the ability to use some camel-hbase provided classes that model HBase data and can be easily convert to and from xml/json etc. Finally it provides the ability to the user to implement and use his own mapping strategy.
Regardless of the mapping strategy camel-hbase will convert a message into an org.apache.camel.component.hbase.model.HBaseData object and use that object for its internal operations.

Configuring the component

The HBase component can be provided a custom HBaseConfiguration object as a property or it can create an HBase configuration object on its own based on the HBase related resources that are found on classpath.
    <bean id="hbase" class="org.apache.camel.component.hbase.HBaseComponent">
        <property name="configuration" ref="config"/>
    </bean>
If no configuration object is provided to the component, the component will create one. The created configuration will search the class path for an hbase-site.xml file, from which it will draw the configuration. You can find more information about how to configure HBase clients at: HBase client configuration and dependencies

HBase Producer

As mentioned above camel provides produers endpoints for HBase. This allows you to store, delete, retrieve or query data from HBase using your camel routes.
hbase://table[?options]
where table is the table name.
The supported operations are:
  • Put
  • Get
  • Delete
  • Scan

Supported URI options on producer

Name Default Value Description
operation CamelHBasePut The HBase operation to perform. Supported values: CamelHBasePut, CamelHBaseGet, CamelHBaseDelete, and CamelHBaseScan.
maxResults 100 The maximum number of rows to scan.Supported operations: CamelHBaseScan.
mappingStrategyName header The strategy to use for mapping Camel messages to HBase columns. Supported values: header, or body.
mappingStrategyClassName null The class name of a custom mapping strategy implementation.
filters null A list of filters. Supported operations: CamelHBaseScan.
Header mapping options:
Name Default Value Description
rowId The id of the row. This has limited use as the row usually changes per Exchange.
rowType String The type to covert row id to. Supported operations: CamelHBaseScan.
family The column family. Supports a number suffix for referring to more than one columns
qualifier The column qualifier. Supports a number suffix for referring to more than one columns
value The value. Supports a number suffix for referring to more than one columns
valueType String The value type. Supports a number suffix for referring to more than one columns. Supported operations: CamelHBaseGet, and CamelHBaseScan.

Put Operations.

HBase is a column based store, which allows you to store data into a specific column of a specific row. Columns are grouped into families, so in order to specify a column you need to specify the column family and the qualifier of that column. To store data into a specific column you need to specify both the column and the row.
The simplest scenario for storing data into HBase from a camel route, would be to store part of the message body to specified HBase column.
        <route>
            <from uri="direct:in"/>
            <!-- Set the HBase Row -->
            <setHeader headerName="CamelHBaseRowId">
                <el>${in.body.id}</el>
            </setHeader>
            <!-- Set the HBase Value -->
            <setHeader headerName="CamelHBaseValue">
                <el>${in.body.value}</el>
            </setHeader>
            <to uri="hbase:mytable?opertaion=CamelHBasePut&amily=myfamily&ualifier=myqualifier"/>
        </route>
The route above assumes that the message body contains an object that has an id and value property and will store the content of value in the HBase column myfamily:myqualifier in the row specified by id. If we needed to specify more than one column/value pairs we could just specify additional column mappings:
        <route>
            <from uri="direct:in"/>
            <!-- Set the HBase Row 1st column -->
            <setHeader headerName="CamelHBaseRowId">
                <el>${in.body.id}</el>
            </setHeader>
            <!-- Set the HBase Row 2nd column -->
            <setHeader headerName="CamelHBaseRowId">
                <el>${in.body.id}</el>
            </setHeader>
            <!-- Set the HBase Value for 1st column -->
            <setHeader headerName="CamelHBaseValue">
                <el>${in.body.value}</el>
            </setHeader>
            <!-- Set the HBase Value for 2nd column -->
            <setHeader headerName="CamelHBaseValue2">
                <el>${in.body.othervalue}</el>
            </setHeader>
            <to uri="hbase:mytable?opertaion=CamelHBasePut&amily=myfamily&ualifier=myqualifier&amily2=myfamily&ualifier2=myqualifier2"/>
        </route>
It is important to remember that you can use uri options, message headers or a combination of both. It is recommended to specify constants as part of the uri and dynamic values as headers. If something is defined both as header and as part of the uri, the header will be used.

Get Operations.

A Get Operation is an operation that is used to retrieve one or more values from a specified HBase row. To specify what are the values that you want to retrieve you can just specify them as part of the uri or as message headers.
        <route>
            <from uri="direct:in"/>
            <!-- Set the HBase Row of the Get -->
            <setHeader headerName="CamelHBaseRowId">
                <el>${in.body.id}</el>
            </setHeader>
            <to uri="hbase:mytable?opertaion=CamelHBaseGet&amily=myfamily&ualifier=myqualifier&alueType=java.lang.Long"/>
            <to uri="log:out"/>
        </route>
In the example above the result of the get operation will be stored as a header with name CamelHBaseValue.

Delete Operations.

You can also you camel-hbase to perform HBase delete operation. The delete operation will remove an entire row. All that needs to be specified is one or more rows as part of the message headers.
        <route>
            <from uri="direct:in"/>
            <!-- Set the HBase Row of the Get -->
            <setHeader headerName="CamelHBaseRowId">
                <el>${in.body.id}</el>
            </setHeader>
            <to uri="hbase:mytable?opertaion=CamelHBaseDelete"/>
        </route>

Scan Operations.

A scan operation is the equivalent of a query in HBase. You can use the scan operation to retrieve multiple rows. To specify what columns should be part of the result and also specify how the values will be converted to objects you can use either uri options or headers.
        <route>
            <from uri="direct:in"/>
            <to uri="hbase:mytable?opertaion=CamelHBaseScan&amily=myfamily&ualifier=myqualifier&alueType=java.lang.Long&owType=java.lang.String"/>
            <to uri="log:out"/>
        </route>
In this case its probable that you also also need to specify a list of filters for limiting the results. You can specify a list of filters as part of the uri and camel will return only the rows that satisfy ALL the filters. To have a filter that will be aware of the information that is part of the message, camel defines the ModelAwareFilter. This will allow your filter to take into consideration the model that is defined by the message and the mapping strategy. When using a ModelAwareFilter camel-hbase will apply the selected mapping strategy to the in message, will create an object that models the mapping and will pass that object to the Filter.
For example to perform scan using as criteria the message headers, you can make use of the ModelAwareColumnMatchingFilter as shown below.
        <route>
            <from uri="direct:scan"/>
            <!-- Set the Criteria -->
            <setHeader headerName="CamelHBaseFamily">
                <constant>name</constant>
            </setHeader>
            <setHeader headerName="CamelHBaseQualifier">
                <constant>first</constant>
            </setHeader>
            <setHeader headerName="CamelHBaseValue">
                <el>in.body.firstName</el>
            </setHeader>
            <setHeader headerName="CamelHBaseFamily2">
                <constant>name</constant>
            </setHeader>
            <setHeader headerName="CamelHBaseQualifier2">
                <constant>last</constant>
            </setHeader>
            <setHeader headerName="CamelHBaseValue2">
                <el>in.body.lastName</el>
            </setHeader>
            <!-- Set additional fields that you want to be return by skipping value -->
            <setHeader headerName="CamelHBaseFamily3">
                <constant>address</constant>
            </setHeader>
            <setHeader headerName="CamelHBaseQualifier3">
                <constant>country</constant>
            </setHeader>
            <to uri="hbase:mytable?opertaion=CamelHBaseScan&ilters=#myFilterList"/>
        </route>

        <bean id="myFilters" class="java.util.ArrayList">
            <constructor-arg>
                <list>
                    <bean class="org.apache.camel.component.hbase.filters.ModelAwareColumnMatchingFilter"/>
                </list>
            </constructor-arg>
        </bean>
The route above assumes that a pojo is with properties firstName and lastName is passed as the message body, it takes those properties and adds them as part of the message headers. The default mapping strategy will create a model object that will map the headers to HBase columns and will pass that model the the ModelAwareColumnMatchingFilter. The filter will filter out any rows, that do not contain columns that match the model. It is like query by example.

HBase Consumer

The Camel HBase Consumer, will perform repeated scan on the specified HBase table and will return the scan results as part of the message. You can either specify header mapping (default) or body mapping. The later will just add the org.apache.camel.component.hbase.model.HBaseData as part of the message body.
hbase://table[?options]
You can specify the columns that you want to be return and their types as part of the uri options:
hbase:mutable?family=name&qualifer=first&valueType=java.lang.String&family=address&qualifer=number&valueType2=java.lang.Integer&rowType=java.lang.Long
The example above will create a model object that is consisted of the specified fields and the scan results will populate the model object with values. Finally the mapping strategy will be used to map this model to the camel message.

Supported URI options on consumer

Name Default Value Description
initialDelay 1000 Milliseconds before the first polling starts.
delay 500 Milliseconds before the next poll.
useFixedDelay true Controls if fixed delay or fixed rate is used. See ScheduledExecutorService in JDK for details.
timeUnit TimeUnit.MILLISECONDS time unit for initialDelay and delay options.
runLoggingLevel TRACE Camel 2.8: The consumer logs a start/complete log line when it polls. This option allows you to configure the logging level for that.
operation CamelHBasePut The HBase operation to perform. Supported values: CamelHBasePut, CamelHBaseGet, CamelHBaseDelete, and CamelHBaseScan.
maxResults 100 The maximum number of rows to scan. Supported operations:CamelHBaseScan.
mappingStrategyName header The strategy to use for mapping Camel messages to HBase columns. Supported values: header, or body.
mappingStrategyClassName null The class name of a custom mapping strategy implementation.
filters null A list of filters. Supported operations: CamelHBaseScan
Header mapping options:
Name Default Value Description
rowId The id of the row. This has limited use as the row usually changes per Exchange.
rowType String The type to covert row id to. Supported operations: CamelHBaseScan
family The column family. *upports a number suffix for referring to more than one columns
qualifier The column qualifier. *Supports a number suffix for referring to more than one columns
value The value. Supports a number suffix for referring to more than one columns
rowModel String An instance of org.apache.camel.component.hbase.model.HBaseRow which describes how each row should be modeled
If the role of the rowModel is not clear, it allows you to construct the HBaseRow modle programmatically instead of "describing" it with uri options (such as family, qualifier, type etc).

HBase Idempotent repository

The camel-hbase component also provides an idempotent repository which can be used when you want to make sure that each message is processed only once. The HBase idempotent repository is configured with a table, a column family and a column qualifier and will create to that table a row per message.
HBaseConfiguration configuration = HBaseConfiguration.create();
HBaseIdempotentRepository repository = new HBaseIdempotentRepository(configuration, tableName, family, qualifier);

from("direct:in")
  .idempotentConsumer(header("messageId"), repository)
  .to("log:out);

HBase Mapping

It was mentioned above that you the default mapping strategies are header and body mapping. Below you can find some detailed examples of how each mapping strategy works.

HBase Header mapping Examples

The header mapping is the default mapping. To put the value "myvalue" into HBase row "myrow" and column "myfamily:mycolum" the message should contain the following headers:
Header Value
CamelHBaseRowId myrow
CamelHBaseFamily myfamily
CamelHBaseQualifier myqualifier
CamelHBaseValue myvalue
To put more values for different columns and / or different rows you can specify additional headers suffixed with the index of the headers, e.g:
Header Value
CamelHBaseRowId myrow
CamelHBaseFamily myfamily
CamelHBaseQualifier myqualifier
CamelHBaseValue myvalue
CamelHBaseRowId2 myrow2
CamelHBaseFamily2 myfamily
CamelHBaseQualifier2 myqualifier
CamelHBaseValue2 myvalue2
In the case of retrieval operations such as get or scan you can also specify for each column the type that you want the data to be converted to. For exampe:
Header Value
CamelHBaseFamily myfamily
CamelHBaseQualifier myqualifier
CamelHBaseValueType Long
Please note that in order to avoid boilerplate headers that are considered constant for all messages, you can also specify them as part of the endpoint uri, as you will see below.

Body mapping Examples

In order to use the body mapping strategy you will have to specify the option mappingStrategy as part of the uri, for example:
hbase:mytable?mappingStrategy=body
To use the body mapping strategy the body needs to contain an instance of org.apache.camel.component.hbase.model.HBaseData. You can construct t
HBaseData data = new HBaseData();
HBaseRow row = new HBaseRow();
row.setId("myRowId");
HBaseCell cell = new HBaseCell();
cell.setFamily("myfamily");
cell.setQualifier("myqualifier");
cell.setValue("myValue");
row.getCells().add(cell);
data.addRows().add(row);
The object above can be used for example in a put operation and will result in creating or updating the row with id myRowId and add the value myvalue to the column myfamily:myqualifier. The body mapping strategy might not seem very appealing at first. The advantage it has over the header mapping strategy is that the HBaseData object can be easily converted to or from xml/json.

Chapter 47. HDFS

HDFS Component

Available as of Camel 2.8
The hdfs component enables you to read and write messages from/to an HDFS file system. HDFS is the distributed file system at the heart of Hadoop.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-hdfs</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

hdfs://hostname[:port][/path][?options]
You can append query options to the URI in the following format, ?option=value&option=value&... The path is treated in the following way:
  1. as a consumer, if it's a file, it just reads the file, otherwise if it represents a directory it scans all the file under the path satisfying the configured pattern. All the files under that directory must be of the same type.
  2. as a producer, if at least one split strategy is defined, the path is considered a directory and under that directory the producer creates a different file per split named seg0, seg1, seg2, etc.

Options

Name Default Value Description
overwrite true The file can be overwritten
append false Append to existing file. Notice that not all HDFS file systems support the append option.
bufferSize 4096 The buffer size used by HDFS
replication 3 The HDFS replication factor
blockSize 67108864 The size of the HDFS blocks
fileType NORMAL_FILE
It can be SEQUENCE_FILE, MAP_FILE, ARRAY_FILE, or BLOOMMAP_FILE, see Hadoop
fileSystemType HDFS It can be LOCAL for local filesystem
keyType NULL
The type for the key in case of sequence or map files. See below.
valueType TEXT
The type for the key in case of sequence or map files. See below.
splitStrategy
A string describing the strategy on how to split the file based on different criteria. See below.
openedSuffix opened
When a file is opened for reading/ writing the file is renamed with this suffix to avoid to read it during the writing phase.
readSuffix read
Once the file has been read is renamed with this suffix to avoid to read it again.
initialDelay 0
For the consumer, how much to wait (milliseconds) before to start scanning the directory.
delay 0
The interval (milliseconds) between the directory scans.
pattern *
The pattern used for scanning the directory