10.3. 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.
`proxyHost`	`null`	Producer	Specify a proxy host to be used inside the client definition.
`proxyPort`	`null`	Producer	Specify a proxy port to be used inside the client definition.

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`	`Map<String, AttributeValue>`	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.
`CamelAwsDdbKeyConditions`	`Map<String, Condition>`	This header specifies the selection criteria for the query, and merges together the two old headers CamelAwsDdbHashKeyValue and CamelAwsDdbScanRangeKeyCondition
`CamelAwsDdbStartKey`	`Key`	Primary key of the item from which to continue an earlier query.
`CamelAwsDdbLimit`	`Integer`	The maximum number of items to return.
`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`	`List<KeySchemaElement>`	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`	`List<KeySchemaElement>`	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).

AWS Component

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