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.
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).