Chapter 6. APNS Component

Available as of Camel version 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>

6.1. URI format

To send notifications:

apns:notify[?options]

To consume feedback:

apns:consumer[?options]

6.2. Options

The APNS component supports 2 options which are listed below.

NameDescriptionDefaultType

apnsService (common)

Required The ApnsService to use. The org.apache.camel.component.apns.factory.ApnsServiceFactory can be used to build a ApnsService

 

ApnsService

resolveProperty Placeholders (advanced)

Whether the component should resolve property placeholders on itself when starting. Only properties which are of String type can use property placeholders.

true

boolean

The APNS endpoint is configured using URI syntax:

apns:name

with the following path and query parameters:

6.2.1. Path Parameters (1 parameters):

NameDescriptionDefaultType

name

Name of the endpoint

 

String

6.2.2. Query Parameters (20 parameters):

NameDescriptionDefaultType

tokens (common)

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

 

String

bridgeErrorHandler (consumer)

Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored.

false

boolean

sendEmptyMessageWhenIdle (consumer)

If the polling consumer did not poll any files, you can enable this option to send an empty message (no body) instead.

false

boolean

exceptionHandler (consumer)

To let the consumer use a custom ExceptionHandler. Notice if the option bridgeErrorHandler is enabled then this options is not in use. By default the consumer will deal with exceptions, that will be logged at WARN or ERROR level and ignored.

 

ExceptionHandler

exchangePattern (consumer)

Sets the exchange pattern when the consumer creates an exchange.

 

ExchangePattern

pollStrategy (consumer)

A pluggable org.apache.camel.PollingConsumerPollingStrategy allowing you to provide your custom implementation to control error handling usually occurred during the poll operation before an Exchange have been created and being routed in Camel.

 

PollingConsumerPoll Strategy

synchronous (advanced)

Sets whether synchronous processing should be strictly used, or Camel is allowed to use asynchronous processing (if supported).

false

boolean

backoffErrorThreshold (scheduler)

The number of subsequent error polls (failed due some error) that should happen before the backoffMultipler should kick-in.

 

int

backoffIdleThreshold (scheduler)

The number of subsequent idle polls that should happen before the backoffMultipler should kick-in.

 

int

backoffMultiplier (scheduler)

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.

 

int

delay (scheduler)

Milliseconds before the next poll. You can also specify time values using units, such as 60s (60 seconds), 5m30s (5 minutes and 30 seconds), and 1h (1 hour).

500

long

greedy (scheduler)

If greedy is enabled, then the ScheduledPollConsumer will run immediately again, if the previous run polled 1 or more messages.

false

boolean

initialDelay (scheduler)

Milliseconds before the first poll starts. You can also specify time values using units, such as 60s (60 seconds), 5m30s (5 minutes and 30 seconds), and 1h (1 hour).

1000

long

runLoggingLevel (scheduler)

The consumer logs a start/complete log line when it polls. This option allows you to configure the logging level for that.

TRACE

LoggingLevel

scheduledExecutorService (scheduler)

Allows for configuring a custom/shared thread pool to use for the consumer. By default each consumer has its own single threaded thread pool.

 

ScheduledExecutor Service

scheduler (scheduler)

To use a cron scheduler from either camel-spring or camel-quartz2 component

none

ScheduledPollConsumer Scheduler

schedulerProperties (scheduler)

To configure additional properties when using a custom scheduler or any of the Quartz2, Spring based scheduler.

 

Map

startScheduler (scheduler)

Whether the scheduler should be auto started.

true

boolean

timeUnit (scheduler)

Time unit for initialDelay and delay options.

MILLISECONDS

TimeUnit

useFixedDelay (scheduler)

Controls if fixed delay or fixed rate is used. See ScheduledExecutorService in JDK for details.

true

boolean

You can append query options to the URI in the following format, ?option=value&option=value&…​

6.2.3. 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.

6.2.3.1. SSL Setting

In order to use secure connection, an instance of org.apache.camel.util.jsse.SSLContextParameters should be injected to org.apache.camel.component.apns.factory.ApnsServiceFactory which is used to configure the component. See the test resources for an example. ssl example

6.3. 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.

6.4. Message Headers

Camel Apns uses these headers.

PropertyDefaultDescription

CamelApnsTokens

 

Empty by default.

CamelApnsMessageType

STRING, PAYLOAD, APNS_NOTIFICATION 

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. From Camel 2.16 onwards APNS_NOTIFICATION is used for sending message body as com.notnoop.apns.ApnsNotification types.

6.5. ApnsServiceFactory builder callback

ApnsServiceFactory comes with the empty callback method that could be used to configure (or even replace) the default ApnsServiceBuilder instance. The signature of the method could look as follows:

protected ApnsServiceBuilder configureServiceBuilder(ApnsServiceBuilder serviceBuilder);

And could be used like as follows:

ApnsServiceFactory proxiedApnsServiceFactory = new ApnsServiceFactory(){
  
  @Override
  protected ApnsServiceBuilder configureServiceBuilder(ApnsServiceBuilder serviceBuilder) {
    return serviceBuilder.withSocksProxy("my.proxy.com", 6666);
  }

};

6.6. Samples

6.6.1. 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&amp;delay=3600&amp;timeUnit=SECONDS" />
                    <to uri="log:org.apache.camel.component.apns?showAll=true&amp;multiline=true" />
                    <to uri="mock:result" />
            </route>
    </camelContext>

</beans>

6.6.2. 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;
    }

[[APNS-ApnsProducer-iOStargetdevicedynamicallyconfiguredviaheader:"CamelApnsTokens"]] 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");

6.7. See Also