10.8. AWS-SQS
SQS Component
Available as of Camel 2.6
The sqs component supports sending and receiving messages to Amazon's SQS service.
Prerequisites
You must have a valid Amazon Web Services developer account, and be signed up to use Amazon SQS. More information are available at Amazon SQS.
URI Format
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&...
URI Options
Name | Default Value | Context | Description |
---|---|---|---|
amazonSQSClient |
null
|
Shared |
Reference to a com.amazonaws.services.sqs.AmazonSQS in the Registry.
|
accessKey |
null
|
Shared | Amazon AWS Access Key |
secretKey |
null
|
Shared | Amazon AWS Secret Key |
amazonSQSEndpoint |
null
|
Shared | The region with which the AWS-SQS client wants to work with. Only works if Camel creates the AWS-SQS client, i.e., if you explicitly set amazonSQSClient, then this setting will have no effect. You would have to set it on the client you create directly. |
attributeNames |
null
|
Consumer |
A list of attributes to set in the com.amazonaws.services.sqs.model.ReceiveMessageRequest .
|
concurrentConsumers |
1
|
Consumer | Camel 2.15.0 Allows you to use multiple threads to poll the SQS queue to increase throughput. |
defaultVisibilityTimeout |
null
|
Shared |
The visibility timeout (in seconds) to set in the com.amazonaws.services.sqs.model.CreateQueueRequest .
|
deleteAfterRead |
true
|
Consumer | Delete message from SQS after it has been read |
deleteIfFiltered |
true
|
Consumer | Camel 2.12.2,2.13.0 Whether or not to send the DeleteMessage to the SQS queue if an exchange fails to get through a filter. If 'false' and exchange does not make it through a Camel filter upstream in the route, then don't send DeleteMessage. |
maxMessagesPerPoll |
null
|
Consumer |
The maximum number of messages which can be received in one poll to set in the com.amazonaws.services.sqs.model.ReceiveMessageRequest .
|
visibilityTimeout |
null
|
Shared |
The duration (in seconds) that the received messages are hidden from subsequent retrieve requests after being retrieved by a ReceiveMessage request to set in the com.amazonaws.services.sqs.model.SetQueueAttributesRequest . This only make sense if its different from defaultVisibilityTimeout . It changes the queue visibility timeout attribute permanently.
|
messageVisibilityTimeout |
null
|
Consumer |
Camel 2.8: The duration (in seconds) that the received messages are hidden from subsequent retrieve requests after being retrieved by a ReceiveMessage request to set in the com.amazonaws.services.sqs.model.ReceiveMessageRequest . It does NOT change the queue visibility timeout attribute permanently.
|
extendMessageVisibility |
false
|
Consumer |
Camel 2.10: If enabled then a scheduled background task will keep extending the message visibility on SQS. This is needed if it taks a long time to process the message. If set to true defaultVisibilityTimeout must be set. See details at Amazon docs.
|
maximumMessageSize |
null
|
Shared |
Camel 2.8: The maximumMessageSize (in bytes) an SQS message can contain for this queue, to set in the com.amazonaws.services.sqs.model.SetQueueAttributesRequest .
|
messageRetentionPeriod |
null
|
Shared |
Camel 2.8: The messageRetentionPeriod (in seconds) a message will be retained by SQS for this queue, to set in the com.amazonaws.services.sqs.model.SetQueueAttributesRequest .
|
policy |
null
|
Shared |
Camel 2.8: The policy for this queue to set in the com.amazonaws.services.sqs.model.SetQueueAttributesRequest .
|
delaySeconds |
null
|
Producer | Camel 2.9.3: Delay sending messages for a number of seconds. |
waitTimeSeconds |
0
|
Producer | Camel 2.11: Duration in seconds (0 to 20) that the ReceiveMessage action call will wait until a message is in the queue to include in the response. |
receiveMessageWaitTimeSeconds |
0
|
Shared | Camel 2.11: If you do not specify WaitTimeSeconds in the request, the queue attribute ReceiveMessageWaitTimeSeconds is used to determine how long to wait. |
queueOwnerAWSAccountId |
null
|
Shared | Camel 2.12: Specify the queue owner aws account id when you need to connect the queue with different account owner. |
region
|
null
|
Shared
|
Camel 2.12.3: Specify the queue region which could be used with
queueOwnerAWSAccountId to build the service URL.
|
redrivePolicy
|
null
|
Shared
|
Camel 2.15.0: Specify the policy that sends a message to DeadLetter queue. See detail at Amazon docs.
|
Required SQS component options
You have to provide the amazonSQSClient in the Registry or your accessKey and secretKey to access the Amazon's SQS.
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.
Usage
Message headers set by the SQS producer
Header | Type | Description |
---|---|---|
CamelAwsSqsMD5OfBody
|
String
|
The MD5 checksum of the Amazon SQS message. |
CamelAwsSqsMessageId
|
String
|
The Amazon SQS message ID. |
CamelAwsSqsDelaySeconds
|
Integer
|
Since Camel 2.11, the delay seconds that the Amazon SQS message can be see by others. |
Message headers set by the SQS consumer
Header | Type | Description |
---|---|---|
CamelAwsSqsMD5OfBody
|
String
|
The MD5 checksum of the Amazon SQS message. |
CamelAwsSqsMessageId
|
String
|
The Amazon SQS message ID. |
CamelAwsSqsReceiptHandle
|
String
|
The Amazon SQS message receipt handle. |
CamelAwsSqsAttributes
|
Map<String, String>
|
The Amazon SQS message attributes. |
Advanced AmazonSQS configuration
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");
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
$\{camel-version\}
must be replaced by the actual version of Camel (2.6 or higher).
JMS-style Selectors
SQS does not allow selectors, but you can effectively achieve this by using the Camel Filter EIP and setting an appropriate
visibilityTimeout
. When SQS dispatches a message, it will wait up to the visibility timeout before it will try to dispatch the message to a different consumer unless a DeleteMessage is received. By default, Camel will always send the DeleteMessage at the end of the route, unless the route ended in failure. To achieve appropriate filtering and not send the DeleteMessage even on successful completion of the route, use a Filter:
from("aws-sqs://MyQueue?amazonSQSClient=#client&defaultVisibilityTimeout=5000&deleteIfFiltered=false") .filter("${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.