Chapter 24. AWS Kinesis Component
Available as of Camel version 2.17
The Kinesis component supports receiving messages from and sending messages to Amazon Kinesis service.
Prerequisites
You must have a valid Amazon Web Services developer account, and be signed up to use Amazon Kinesis. More information are available at AWS Kinesis
24.1. URI Format
aws-kinesis://stream-name[?options]
The stream needs to be created prior to it being used.
You can append query options to the URI in the following format, ?options=value&option2=value&…
24.2. URI Options
The AWS Kinesis component supports 5 options which are listed below.
| Name | Description | Default | Type |
|---|---|---|---|
| configuration (advanced) | The AWS S3 default configuration | KinesisConfiguration | |
| accessKey (common) | Amazon AWS Access Key | String | |
| secretKey (common) | Amazon AWS Secret Key | String | |
| region (common) | Amazon AWS Region | 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 Kinesis endpoint is configured using URI syntax:
aws-kinesis:streamName
with the following path and query parameters:
24.2.1. Path Parameters (1 parameters):
| Name | Description | Default | Type |
|---|---|---|---|
| streamName | Required Name of the stream | String |
24.2.2. Query Parameters (30 parameters):
| Name | Description | Default | Type |
|---|---|---|---|
| amazonKinesisClient (common) | Amazon Kinesis client to use for all requests for this endpoint | AmazonKinesis | |
| proxyHost (common) | To define a proxy host when instantiating the DDBStreams client | String | |
| proxyPort (common) | To define a proxy port when instantiating the DDBStreams client | Integer | |
| region (common) | The region in which Kinesis client needs to work | String | |
| bridgeErrorHandler (consumer) | Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored. | false | boolean |
| iteratorType (consumer) | Defines where in the Kinesis stream to start getting records | TRIM_HORIZON | ShardIteratorType |
| maxResultsPerRequest (consumer) | Maximum number of records that will be fetched in each poll | 1 | int |
| sendEmptyMessageWhenIdle (consumer) | If the polling consumer did not poll any files, you can enable this option to send an empty message (no body) instead. | false | boolean |
| sequenceNumber (consumer) | The sequence number to start polling from. Required if iteratorType is set to AFTER_SEQUENCE_NUMBER or AT_SEQUENCE_NUMBER | String | |
| shardClosed (consumer) | Define what will be the behavior in case of shard closed. Possible value are ignore, silent and fail.In case of ignore a message will be logged and the consumer will restart from the beginning,in case of silent there will be no logging and the consumer will start from the beginning,in case of fail a ReachedClosedStateException will be raised | ignore | KinesisShardClosed StrategyEnum |
| shardId (consumer) | Defines which shardId in the Kinesis stream to get records from | String | |
| exceptionHandler (consumer) | To let the consumer use a custom ExceptionHandler. Notice if the option bridgeErrorHandler is enabled then this options is not in use. By default the consumer will deal with exceptions, that will be logged at WARN or ERROR level and ignored. | ExceptionHandler | |
| exchangePattern (consumer) | Sets the exchange pattern when the consumer creates an exchange. | ExchangePattern | |
| pollStrategy (consumer) | A pluggable org.apache.camel.PollingConsumerPollingStrategy allowing you to provide your custom implementation to control error handling usually occurred during the poll operation before an Exchange have been created and being routed in Camel. | PollingConsumerPoll Strategy | |
| synchronous (advanced) | Sets whether synchronous processing should be strictly used, or Camel is allowed to use asynchronous processing (if supported). | false | boolean |
| backoffErrorThreshold (scheduler) | The number of subsequent error polls (failed due some error) that should happen before the backoffMultipler should kick-in. | int | |
| backoffIdleThreshold (scheduler) | The number of subsequent idle polls that should happen before the backoffMultipler should kick-in. | int | |
| backoffMultiplier (scheduler) | To let the scheduled polling consumer backoff if there has been a number of subsequent idles/errors in a row. The multiplier is then the number of polls that will be skipped before the next actual attempt is happening again. When this option is in use then backoffIdleThreshold and/or backoffErrorThreshold must also be configured. | int | |
| delay (scheduler) | Milliseconds before the next poll. You can also specify time values using units, such as 60s (60 seconds), 5m30s (5 minutes and 30 seconds), and 1h (1 hour). | 500 | long |
| greedy (scheduler) | If greedy is enabled, then the ScheduledPollConsumer will run immediately again, if the previous run polled 1 or more messages. | false | boolean |
| initialDelay (scheduler) | Milliseconds before the first poll starts. You can also specify time values using units, such as 60s (60 seconds), 5m30s (5 minutes and 30 seconds), and 1h (1 hour). | 1000 | long |
| runLoggingLevel (scheduler) | The consumer logs a start/complete log line when it polls. This option allows you to configure the logging level for that. | TRACE | LoggingLevel |
| scheduledExecutorService (scheduler) | Allows for configuring a custom/shared thread pool to use for the consumer. By default each consumer has its own single threaded thread pool. | ScheduledExecutor Service | |
| scheduler (scheduler) | To use a cron scheduler from either camel-spring or camel-quartz2 component | none | ScheduledPollConsumer Scheduler |
| schedulerProperties (scheduler) | To configure additional properties when using a custom scheduler or any of the Quartz2, Spring based scheduler. | Map | |
| startScheduler (scheduler) | Whether the scheduler should be auto started. | true | boolean |
| timeUnit (scheduler) | Time unit for initialDelay and delay options. | MILLISECONDS | TimeUnit |
| useFixedDelay (scheduler) | Controls if fixed delay or fixed rate is used. See ScheduledExecutorService in JDK for details. | true | boolean |
| accessKey (security) | Amazon AWS Access Key | String | |
| secretKey (security) | Amazon AWS Secret Key | String |
Required Kinesis component options
You have to provide the amazonKinesisClient in the Registry with proxies and relevant credentials configured.
24.3. Batch Consumer
This component implements the Batch Consumer.
This allows you for instance to know how many messages exists in this batch and for instance let the Aggregator aggregate this number of messages.
24.4. Usage
24.4.1. Message headers set by the Kinesis consumer
| Header | Type | Description |
|---|---|---|
|
|
| The sequence number of the record. This is represented as a String as it size is not defined by the API. If it is to be used as a numerical type then use |
|
|
| The time AWS assigned as the arrival time of the record. |
|
|
| Identifies which shard in the stream the data record is assigned to. |
24.4.2. AmazonKinesis configuration
You will need to create an instance of AmazonKinesisClient and bind it to the registry
ClientConfiguration clientConfiguration = new ClientConfiguration();
clientConfiguration.setProxyHost("http://myProxyHost");
clientConfiguration.setProxyPort(8080);
Region region = Region.getRegion(Regions.fromName(region));
region.createClient(AmazonKinesisClient.class, null, clientConfiguration);
// the 'null' here is the AWSCredentialsProvider which defaults to an instance of DefaultAWSCredentialsProviderChain
registry.bind("kinesisClient", client);
You then have to reference the AmazonKinesisClient in the amazonKinesisClient URI option.
from("aws-kinesis://mykinesisstream?amazonKinesisClient=#kinesisClient")
.to("log:out?showAll=true");24.4.3. Providing AWS Credentials
It is recommended that the credentials are obtained by using the DefaultAWSCredentialsProviderChain that is the default when creating a new ClientConfiguration instance, however, a different AWSCredentialsProvider can be specified when calling createClient(…).
24.4.4. Message headers used by the Kinesis producer to write to Kinesis. The producer expects that the message body is a ByteBuffer.
| Header | Type | Description |
|---|---|---|
|
|
| The PartitionKey to pass to Kinesis to store this record. |
|
|
| Optional paramter to indicate the sequence number of this record. |
24.4.5. Message headers set by the Kinesis producer on successful storage of a Record
| Header | Type | Description |
|---|---|---|
|
|
| The sequence number of the record, as defined in Response Syntax |
|
|
| The shard ID of where the Record was stored |
24.5. 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 (2.17 or higher).
24.6. See Also
- Configuring Camel
- Component
- Endpoint
- Getting Started
- AWS Component
