Chapter 21. AWS DynamoDB Component

Available as of Camel version 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.

21.1. URI Format

aws-ddb://domainName[?options]

You can append query options to the URI in the following format, ?options=value&option2=value&…​

21.2. URI Options

The AWS DynamoDB component supports 5 options which are listed below.

NameDescriptionDefaultType

configuration (advanced)

The AWS DDB default configuration

 

DdbConfiguration

accessKey (producer)

Amazon AWS Access Key

 

String

secretKey (producer)

Amazon AWS Secret Key

 

String

region (producer)

The region in which DDB client needs to work

 

String

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 AWS DynamoDB endpoint is configured using URI syntax:

aws-ddb:tableName

with the following path and query parameters:

21.2.1. Path Parameters (1 parameters):

NameDescriptionDefaultType

tableName

Required The name of the table currently worked with.

 

String

21.2.2. Query Parameters (13 parameters):

NameDescriptionDefaultType

amazonDDBClient (producer)

To use the AmazonDynamoDB as the client

 

AmazonDynamoDB

consistentRead (producer)

Determines whether or not strong consistency should be enforced when data is read.

false

boolean

keyAttributeName (producer)

Attribute name when creating table

 

String

keyAttributeType (producer)

Attribute type when creating table

 

String

operation (producer)

What operation to perform

PutItem

DdbOperations

proxyHost (producer)

To define a proxy host when instantiating the DDB client

 

String

proxyPort (producer)

To define a proxy port when instantiating the DDB client

 

Integer

readCapacity (producer)

The provisioned throughput to reserve for reading resources from your table

 

Long

region (producer)

The region in which DDB client needs to work

 

String

writeCapacity (producer)

The provisioned throughput to reserved for writing resources to your table

 

Long

synchronous (advanced)

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

false

boolean

accessKey (security)

Amazon AWS Access Key

 

String

secretKey (security)

Amazon AWS Secret Key

 

String

Required DDB component options

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

21.3. Usage

21.3.1. Message headers evaluated by the DDB producer

HeaderTypeDescription

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. From Camel 2.16.0 the type of this header is Map<String, AttributeValue> and not Key

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.

CamelAwsDdbIndexName

String

If set will be used as Secondary Index for Query operation.

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. From Camel 2.16.0 this header doesn’t exist anymore.

CamelAwsDdbKeyConditions

Map<String, Condition>

From Camel 2.16.0. This header specify the selection criteria for the query, and merge together the two old headers CamelAwsDdbHashKeyValue and CamelAwsDdbScanRangeKeyCondition

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. From Camel 2.16.0 this header doesn’t exist anymore.

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.From Camel 2.16.0 this header doesn’t exist anymore.

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.

21.3.2. Message headers set during BatchGetItems operation

HeaderTypeDescription

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.

21.3.3. Message headers set during DeleteItem operation

HeaderTypeDescription

CamelAwsDdbAttributes

Map<String, AttributeValue>

The list of attributes returned by the operation.

21.3.4. Message headers set during DeleteTable operation

HeaderTypeDescription

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. From Camel 2.16.0 the type of this header is List<KeySchemaElement> and not KeySchema

CamelAwsDdbTableName

String

The table name.

CamelAwsDdbTableSize

Long

The table size in bytes.

CamelAwsDdbTableStatus

String

The status of the table: CREATING, UPDATING, DELETING, ACTIVE

21.3.5. Message headers set during DescribeTable operation

HeaderTypeDescription

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. From Camel 2.16.0 the type of this header is List<KeySchemaElement> and not KeySchema

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.

21.3.6. Message headers set during GetItem operation

HeaderTypeDescription

CamelAwsDdbAttributes

Map<String, AttributeValue>

The list of attributes returned by the operation.

21.3.7. Message headers set during PutItem operation

HeaderTypeDescription

CamelAwsDdbAttributes

Map<String, AttributeValue>

The list of attributes returned by the operation.

21.3.8. Message headers set during Query operation

HeaderTypeDescription

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.

21.3.9. Message headers set during Scan operation

HeaderTypeDescription

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.

21.3.10. Message headers set during UpdateItem operation

HeaderTypeDescription

CamelAwsDdbAttributes

Map<String, AttributeValue>

The list of attributes returned by the operation.

21.3.11. 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);

21.4. 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).

21.5. See Also

  • Configuring Camel
  • Component
  • Endpoint
  • Getting Started
  • AWS Component