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Chapter 22. 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.
22.1. URI Format
aws-ddb://domainName[?options]
You can append query options to the URI in the following format, ?options=value&option2=value&…
22.2. 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:
22.2.1. Path Parameters (1 parameters):
| Name | Description | Default | Type |
|---|---|---|---|
| tableName | Required The name of the table currently worked with. | String |
22.2.2. 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 |
Required DDB component options
You have to provide the amazonDDBClient in the Registry or your accessKey and secretKey to access the Amazon’s DynamoDB.
22.3. Usage
22.3.1. Message headers evaluated by the DDB producer
| Header | Type | Description |
|---|---|---|
|
|
| A map of the table name and corresponding items to get by primary key. |
|
|
| Table Name for this operation. |
|
|
| 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 |
|
|
| 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). |
|
|
| Designates an attribute for a conditional modification. |
|
|
| If attribute names are not specified then all attributes will be returned. |
|
|
| If set to true, then a consistent read is issued, otherwise eventually consistent is used. |
|
|
| If set will be used as Secondary Index for Query operation. |
|
|
| A map of the attributes for the item, and must include the primary key values that define the item. |
|
|
| 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. |
|
|
| From Camel 2.16.0. This header specify the selection criteria for the query, and merge together the two old headers CamelAwsDdbHashKeyValue and CamelAwsDdbScanRangeKeyCondition |
|
|
| Primary key of the item from which to continue an earlier query. |
|
|
| Value of the hash component of the composite primary key. From Camel 2.16.0 this header doesn’t exist anymore. |
|
|
| The maximum number of items to return. |
|
|
| 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. |
|
|
| Specifies forward or backward traversal of the index. |
|
|
| Evaluates the scan results and returns only the desired values. |
|
|
| Map of attribute name to the new value and action for the update. |
22.3.2. Message headers set during BatchGetItems operation
| Header | Type | Description |
|---|---|---|
|
|
| Table names and the respective item attributes from the tables. |
|
|
| Contains a map of tables and their respective keys that were not processed with the current response. |
22.3.3. Message headers set during DeleteItem operation
| Header | Type | Description |
|---|---|---|
|
|
| The list of attributes returned by the operation. |
22.3.4. Message headers set during DeleteTable operation
| Header | Type | Description |
|---|---|---|
|
| ||
|
| The value of the ProvisionedThroughput property for this table | |
|
|
| Creation DateTime of this table. |
|
|
| Item count for this table. |
|
|
| 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 |
|
|
| The table name. |
|
|
| The table size in bytes. |
|
|
| The status of the table: CREATING, UPDATING, DELETING, ACTIVE |
22.3.5. Message headers set during DescribeTable operation
| Header | Type | Description |
|---|---|---|
|
| {{ProvisionedThroughputDescription}} | The value of the ProvisionedThroughput property for this table |
|
|
| Creation DateTime of this table. |
|
|
| Item count for this table. |
|
| {{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 |
|
|
| The table name. |
|
|
| The table size in bytes. |
|
|
| The status of the table: CREATING, UPDATING, DELETING, ACTIVE |
|
|
| ReadCapacityUnits property of this table. |
|
|
| WriteCapacityUnits property of this table. |
22.3.6. Message headers set during GetItem operation
| Header | Type | Description |
|---|---|---|
|
|
| The list of attributes returned by the operation. |
22.3.7. Message headers set during PutItem operation
| Header | Type | Description |
|---|---|---|
|
|
| The list of attributes returned by the operation. |
22.3.8. Message headers set during Query operation
| Header | Type | Description |
|---|---|---|
|
|
| The list of attributes returned by the operation. |
|
|
| Primary key of the item where the query operation stopped, inclusive of the previous result set. |
|
|
| The number of Capacity Units of the provisioned throughput of the table consumed during the operation. |
|
|
| Number of items in the response. |
22.3.9. Message headers set during Scan operation
| Header | Type | Description |
|---|---|---|
|
|
| The list of attributes returned by the operation. |
|
|
| Primary key of the item where the query operation stopped, inclusive of the previous result set. |
|
|
| The number of Capacity Units of the provisioned throughput of the table consumed during the operation. |
|
|
| Number of items in the response. |
|
|
| Number of items in the complete scan before any filters are applied. |
22.3.10. Message headers set during UpdateItem operation
| Header | Type | Description |
|---|---|---|
|
|
| The list of attributes returned by the operation. |
22.3.11. 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);22.4. 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).
22.5. See Also
- Configuring Camel
- Component
- Endpoint
- Getting Started
- AWS Component
