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Chapter 23. 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.

23.1. URI Format

aws-ddb://domainName[?options]

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

23.2. URI Options

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

Name	Description	Default	Type
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:

23.2.1. Path Parameters (1 parameters):

Name	Description	Default	Type
tableName	Required The name of the table currently worked with.		String

23.2.2. Query Parameters (13 parameters):

Name	Description	Default	Type
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

23.3. Spring Boot Auto-Configuration

The component supports 18 options, which are listed below.

Name	Description	Default	Type
camel.component.aws-ddb.access-key	Amazon AWS Access Key		String
camel.component.aws-ddb.configuration.access-key	Amazon AWS Access Key		String
camel.component.aws-ddb.configuration.amazon-d-d-b-client	To use the AmazonDynamoDB as the client		AmazonDynamoDB
camel.component.aws-ddb.configuration.consistent-read	Determines whether or not strong consistency should be enforced when data is read.	false	Boolean
camel.component.aws-ddb.configuration.key-attribute-name	Attribute name when creating table		String
camel.component.aws-ddb.configuration.key-attribute-type	Attribute type when creating table		String
camel.component.aws-ddb.configuration.operation	What operation to perform		DdbOperations
camel.component.aws-ddb.configuration.proxy-host	To define a proxy host when instantiating the DDB client		String
camel.component.aws-ddb.configuration.proxy-port	To define a proxy port when instantiating the DDB client		Integer
camel.component.aws-ddb.configuration.read-capacity	The provisioned throughput to reserve for reading resources from your table		Long
camel.component.aws-ddb.configuration.region	The region in which DDB client needs to work		String
camel.component.aws-ddb.configuration.secret-key	Amazon AWS Secret Key		String
camel.component.aws-ddb.configuration.table-name	The name of the table currently worked with.		String
camel.component.aws-ddb.configuration.write-capacity	The provisioned throughput to reserved for writing resources to your table		Long
camel.component.aws-ddb.enabled	Enable aws-ddb component	true	Boolean
camel.component.aws-ddb.region	The region in which DDB client needs to work		String
camel.component.aws-ddb.resolve-property-placeholders	Whether the component should resolve property placeholders on itself when starting. Only properties which are of String type can use property placeholders.	true	Boolean
camel.component.aws-ddb.secret-key	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.

23.4. Usage

23.4.1. 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. 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.

23.4.2. 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.

23.4.3. Message headers set during DeleteItem operation

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

23.4.4. 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. 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

23.4.5. 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. 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.

23.4.6. Message headers set during GetItem operation

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

23.4.7. Message headers set during PutItem operation

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

23.4.8. 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.

23.4.9. 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.

23.4.10. Message headers set during UpdateItem operation

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

23.4.11. 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);

23.5. 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).

23.6. See Also

Configuring Camel
Component
Endpoint
Getting Started
AWS Component