amazonka-datapipeline-0.2.1: Amazon Data Pipeline SDK.

Safe HaskellNone
LanguageHaskell2010

Network.AWS.DataPipeline.PollForTask

Contents

Description

Task runners call this action to receive a task to perform from AWS Data Pipeline. The task runner specifies which tasks it can perform by setting a value for the workerGroup parameter of the PollForTask call. The task returned by PollForTask may come from any of the pipelines that match the workerGroup value passed in by the task runner and that was launched using the IAM user credentials specified by the task runner.

If tasks are ready in the work queue, PollForTask returns a response immediately. If no tasks are available in the queue, PollForTask uses long-polling and holds on to a poll connection for up to a 90 seconds during which time the first newly scheduled task is handed to the task runner. To accomodate this, set the socket timeout in your task runner to 90 seconds. The task runner should not call PollForTask again on the same workerGroup until it receives a response, and this may take up to 90 seconds.

http://docs.aws.amazon.com/datapipeline/latest/APIReference/API_PollForTask.html

Synopsis

Request

Request constructor

pollForTask Source

PollForTask constructor.

The fields accessible through corresponding lenses are:

Request lenses

pftHostname :: Lens' PollForTask (Maybe Text) Source

The public DNS name of the calling task runner.

pftInstanceIdentity :: Lens' PollForTask (Maybe InstanceIdentity) Source

Identity information for the Amazon EC2 instance that is hosting the task runner. You can get this value by calling the URI, 'http://169.254.169.254/latest/meta-data/instance-id', from the EC2 instance. For more information, go to Instance Metadata in the Amazon Elastic Compute Cloud User Guide. Passing in this value proves that your task runner is running on an EC2 instance, and ensures the proper AWS Data Pipeline service charges are applied to your pipeline.

pftWorkerGroup :: Lens' PollForTask Text Source

Indicates the type of task the task runner is configured to accept and process. The worker group is set as a field on objects in the pipeline when they are created. You can only specify a single value for workerGroup in the call to PollForTask. There are no wildcard values permitted in workerGroup, the string must be an exact, case-sensitive, match.

Response

Response constructor

pollForTaskResponse :: PollForTaskResponse Source

PollForTaskResponse constructor.

The fields accessible through corresponding lenses are:

Response lenses

pftrTaskObject :: Lens' PollForTaskResponse (Maybe TaskObject) Source

An instance of TaskObject. The returned object contains all the information needed to complete the task that is being assigned to the task runner. One of the fields returned in this object is taskId, which contains an identifier for the task being assigned. The calling task runner uses taskId in subsequent calls to ReportTaskProgress and SetTaskStatus.