The Amazon Simple Workflow Service (Amazon SWF) makes it easy to build applications that use Amazon's cloud to coordinate work across distributed components. In Amazon SWF, a task represents a logical unit of work that is performed by a component of your workflow. Coordinating tasks in a workflow involves managing intertask dependencies, scheduling, and concurrency in accordance with the logical flow of the application.
Amazon SWF gives you full control over implementing tasks and coordinating them without worrying about underlying complexities such as tracking their progress and maintaining their state.
This documentation serves as reference only. For a broader overview of the Amazon SWF programming model, see the Amazon SWF Developer Guide .
x-logo: url: https://twitter.com/awscloud/profile_image?size=original backgroundColor: '#FFFFFF' termsOfService: https://aws.amazon.com/service-terms/ contact: name: Mike Ralphson email: mike.ralphson@gmail.com url: https://github.com/mermade/aws2openapi x-twitter: PermittedSoc license: name: Apache 2.0 License url: http://www.apache.org/licenses/ x-providerName: amazonaws.com x-serviceName: swf x-origin: - contentType: application/json url: https://raw.githubusercontent.com/aws/aws-sdk-js/master/apis/swf-2012-01-25.normal.json converter: url: https://github.com/mermade/aws2openapi version: 1.0.0 x-apisguru-driver: external x-apiClientRegistration: url: https://portal.aws.amazon.com/gp/aws/developer/registration/index.html?nc2=h_ct x-apisguru-categories: - cloud x-preferred: true servers: - url: http://swf.{region}.amazonaws.com variables: region: description: The AWS region enum: - us-east-1 - us-east-2 - us-west-1 - us-west-2 - us-gov-west-1 - us-gov-east-1 - ca-central-1 - eu-north-1 - eu-west-1 - eu-west-2 - eu-west-3 - eu-central-1 - eu-south-1 - af-south-1 - ap-northeast-1 - ap-northeast-2 - ap-northeast-3 - ap-southeast-1 - ap-southeast-2 - ap-east-1 - ap-south-1 - sa-east-1 - me-south-1 default: us-east-1 description: The Amazon SWF multi-region endpoint - url: https://swf.{region}.amazonaws.com variables: region: description: The AWS region enum: - us-east-1 - us-east-2 - us-west-1 - us-west-2 - us-gov-west-1 - us-gov-east-1 - ca-central-1 - eu-north-1 - eu-west-1 - eu-west-2 - eu-west-3 - eu-central-1 - eu-south-1 - af-south-1 - ap-northeast-1 - ap-northeast-2 - ap-northeast-3 - ap-southeast-1 - ap-southeast-2 - ap-east-1 - ap-south-1 - sa-east-1 - me-south-1 default: us-east-1 description: The Amazon SWF multi-region endpoint - url: http://swf.{region}.amazonaws.com.cn variables: region: description: The AWS region enum: - cn-north-1 - cn-northwest-1 default: cn-north-1 description: The Amazon SWF endpoint for China (Beijing) and China (Ningxia) - url: https://swf.{region}.amazonaws.com.cn variables: region: description: The AWS region enum: - cn-north-1 - cn-northwest-1 default: cn-north-1 description: The Amazon SWF endpoint for China (Beijing) and China (Ningxia) security: - hmac: [] tags: - name: '#X Amz Target=SimpleWorkflowService.RespondActivityTaskCanceled' paths: /#X-Amz-Target=SimpleWorkflowService.RespondActivityTaskCanceled: parameters: - $ref: '#/components/parameters/X-Amz-Content-Sha256' - $ref: '#/components/parameters/X-Amz-Date' - $ref: '#/components/parameters/X-Amz-Algorithm' - $ref: '#/components/parameters/X-Amz-Credential' - $ref: '#/components/parameters/X-Amz-Security-Token' - $ref: '#/components/parameters/X-Amz-Signature' - $ref: '#/components/parameters/X-Amz-SignedHeaders' post: operationId: RespondActivityTaskCanceled description:Used by workers to tell the service that the ActivityTask identified by the taskToken was successfully canceled. Additional details can be provided using the details argument.
These details (if provided) appear in the ActivityTaskCanceled event added to the workflow history.
Only use this operation if the canceled flag of a RecordActivityTaskHeartbeat request returns true and if the activity can be safely undone or abandoned.
A task is considered open from the time that it is scheduled until it is closed. Therefore a task is reported as open while a worker is processing it. A task is closed after it has been specified in a call to RespondActivityTaskCompleted, RespondActivityTaskCanceled, RespondActivityTaskFailed, or the task has timed out.
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.
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.