RecordActivityTaskHeartbeat - Amazon Simple Workflow Service


Used by activity workers to report to the service that the ActivityTask represented by the specified taskToken is still making progress. The worker can also specify details of the progress, for example percent complete, using the details parameter. This action can also be used by the worker as a mechanism to check if cancellation is being requested for the activity task. If a cancellation is being attempted for the specified task, then the boolean cancelRequested flag returned by the service is set to true.

This action resets the taskHeartbeatTimeout clock. The taskHeartbeatTimeout is specified in RegisterActivityType.

This action doesn't in itself create an event in the workflow execution history. However, if the task times out, the workflow execution history contains a ActivityTaskTimedOut event that contains the information from the last heartbeat generated by the activity worker.


The taskStartToCloseTimeout of an activity type is the maximum duration of an activity task, regardless of the number of RecordActivityTaskHeartbeat requests received. The taskStartToCloseTimeout is also specified in RegisterActivityType.


This operation is only useful for long-lived activities to report liveliness of the task and to determine if a cancellation is being attempted.


If the cancelRequested flag returns true, a cancellation is being attempted. If the worker can cancel the activity, it should respond with RespondActivityTaskCanceled. Otherwise, it should ignore the cancellation request.

Access Control

You can use IAM policies to control this action's access to Amazon SWF resources as follows:

  • Use a Resource element with the domain name to limit the action to only specified domains.

  • Use an Action element to allow or deny permission to call this action.

  • You cannot use an IAM policy to constrain this action's parameters.

If the caller doesn't have sufficient permissions to invoke the action, or the parameter values fall outside the specified constraints, the action fails. The associated event attribute's cause parameter is set to OPERATION_NOT_PERMITTED. For details and example IAM policies, see Using IAM to Manage Access to Amazon SWF Workflows in the Amazon SWF Developer Guide.

Request Syntax

{ "details": "string", "taskToken": "string" }

Request Parameters

For information about the parameters that are common to all actions, see Common Parameters.

The request accepts the following data in JSON format.


If specified, contains details about the progress of the task.

Type: String

Length Constraints: Maximum length of 2048.

Required: No


The taskToken of the ActivityTask.


taskToken is generated by the service and should be treated as an opaque value. If the task is passed to another process, its taskToken must also be passed. This enables it to provide its progress and respond with results.

Type: String

Length Constraints: Minimum length of 1. Maximum length of 1024.

Required: Yes

Response Syntax

{ "cancelRequested": boolean }

Response Elements

If the action is successful, the service sends back an HTTP 200 response.

The following data is returned in JSON format by the service.


Set to true if cancellation of the task is requested.

Type: Boolean


For information about the errors that are common to all actions, see Common Errors.


Returned when the caller doesn't have sufficient permissions to invoke the action.

HTTP Status Code: 400


Returned when the named resource cannot be found with in the scope of this operation (region or domain). This could happen if the named resource was never created or is no longer available for this operation.

HTTP Status Code: 400


RecordActivityTaskHeartbeat Example

This example illustrates one usage of RecordActivityTaskHeartbeat.

Sample Request

POST / HTTP/1.1 Host: User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv: Gecko/20111212 Firefox/3.6.25 ( .NET CLR 3.5.30729; .NET4.0E) Accept: application/json, text/javascript, */* Accept-Language: en-us,en;q=0.5 Accept-Encoding: gzip,deflate Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7 Keep-Alive: 115 Connection: keep-alive Content-Type: application/x-amz-json-1.0 X-Requested-With: XMLHttpRequest X-Amz-Date: Mon, 16 Jan 2012 03:55:06 GMT X-Amz-Target: SimpleWorkflowService.RecordActivityTaskHeartbeat Content-Encoding: amz-1.0 X-Amzn-Authorization: AWS3 AWSAccessKeyId=AKIAIOSFODNN7EXAMPLE,Algorithm=HmacSHA256,SignedHeaders=Host;X-Amz-Date;X-Amz-Target;Content-Encoding,Signature=DEA8rw5TqtpqCeTljl7eotZkuWTgmGZ1PWyDNZPehT0= Referer: Content-Length: 623 Pragma: no-cache Cache-Control: no-cache {"taskToken": "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", "details": "starting task"}

Sample Response

HTTP/1.1 200 OK Content-Length: 25 Content-Type: application/json x-amzn-RequestId: e08622cd-3ff5-11e1-9b11-7182192d0b57 {"cancelRequested":false}

See Also

For more information about using this API in one of the language-specific AWS SDKs, see the following: