Class PollForActivityTaskCommandProtected

Used by workers to get an ActivityTask from the specified activity taskList. This initiates a long poll, where the service holds the HTTP connection open and responds as soon as a task becomes available. The maximum time the service holds on to the request before responding is 60 seconds. If no task is available within 60 seconds, the poll returns an empty result. An empty result, in this context, means that an ActivityTask is returned, but that the value of taskToken is an empty string. If a task is returned, the worker should use its type to identify and process it correctly.

Workers should set their client side socket timeout to at least 70 seconds (10 seconds higher than the maximum time service may hold the poll 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.

• Constrain the taskList.name parameter by using a Condition element with the swf:taskList.name key to allow the action to access only certain task lists.

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.

Example

Use a bare-bones client and the command you need to make an API call.

import { SWFClient, PollForActivityTaskCommand } from "@aws-sdk/client-swf"; // ES Modules import
// const { SWFClient, PollForActivityTaskCommand } = require("@aws-sdk/client-swf"); // CommonJS import
const client = new SWFClient(config);
const input = { // PollForActivityTaskInput
  domain: "STRING_VALUE", // required
  taskList: { // TaskList
    name: "STRING_VALUE", // required
  },
  identity: "STRING_VALUE",
};
const command = new PollForActivityTaskCommand(input);
const response = await client.send(command);
// { // ActivityTask
//   taskToken: "STRING_VALUE", // required
//   activityId: "STRING_VALUE", // required
//   startedEventId: Number("long"), // required
//   workflowExecution: { // WorkflowExecution
//     workflowId: "STRING_VALUE", // required
//     runId: "STRING_VALUE", // required
//   },
//   activityType: { // ActivityType
//     name: "STRING_VALUE", // required
//     version: "STRING_VALUE", // required
//   },
//   input: "STRING_VALUE",
// };

Param

PollForActivityTaskCommandInput

Returns

PollForActivityTaskCommandOutput

See

• PollForActivityTaskCommandInput for command's input shape.
• PollForActivityTaskCommandOutput for command's response shape.
• config for SWFClient's config shape.

Throws

LimitExceededFault (client fault)

Returned by any operation if a system imposed limitation has been reached. To address this fault you should either clean up unused resources or increase the limit by contacting AWS.

Throws

OperationNotPermittedFault (client fault)

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

Throws

UnknownResourceFault (client fault)

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.

Throws

SWFServiceException

Base exception class for all service exceptions from SWF service.