10.8. AWS-SQS

Available as of Camel 2.6

The sqs component supports sending and receiving messages to Amazon's SQS service.

aws-sqs://queue-name[?options]

The queue will be created if they don't already exists. You can append query options to the URI in the following format, ?options=value&option2=value&...

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.

If your Camel Application is running behind a firewall or if you need to have more control over the AmazonSQS instance configuration, you can create your own instance:

AWSCredentials awsCredentials = new BasicAWSCredentials("myAccessKey", "mySecretKey");

ClientConfiguration clientConfiguration = new ClientConfiguration();
clientConfiguration.setProxyHost("http://myProxyHost");
clientConfiguration.setProxyPort(8080);

AmazonSQS client = new AmazonSQSClient(awsCredentials, clientConfiguration);

registry.bind("client", client);

and refer to it in your Camel aws-sqs component configuration:

from("aws-sqs://MyQueue?amazonSQSClient=#client&delay=5000&maxMessagesPerPoll=5")
.to("mock:result");

Maven users will need to add the following dependency to their 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 (2.6 or higher).

SQS does not allow selectors, but you can effectively achieve this by using the Camel Filter EIP and setting an appropriate visibilityTimeout. When SQS dispatches a message, it will wait up to the visibility timeout before it will try to dispatch the message to a different consumer unless a DeleteMessage is received. By default, Camel will always send the DeleteMessage at the end of the route, unless the route ended in failure. To achieve appropriate filtering and not send the DeleteMessage even on successful completion of the route, use a Filter:

from("aws-sqs://MyQueue?amazonSQSClient=#client&defaultVisibilityTimeout=5000&deleteIfFiltered=false")
.filter("${header.login} == true")
.to("mock:result");

In the above code, if an exchange doesn't have an appropriate header, it will not make it through the filter AND also not be deleted from the SQS queue. After 5000 miliseconds, the message will become visible to other consumers.