StartWorkflowExecutionCommand

Starts an execution of the workflow type in the specified domain using the provided workflowId and input data.

This action returns the newly started workflow execution.

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 following parameters by using a Condition element with the appropriate keys.

    • tagList.member.0: The key is swf:tagList.member.0.

    • tagList.member.1: The key is swf:tagList.member.1.

    • tagList.member.2: The key is swf:tagList.member.2.

    • tagList.member.3: The key is swf:tagList.member.3.

    • tagList.member.4: The key is swf:tagList.member.4.

    • taskList: String constraint. The key is swf:taskList.name.

    • workflowType.name: String constraint. The key is swf:workflowType.name.

    • workflowType.version: String constraint. The key is swf:workflowType.version.

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 Syntax

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

import { SWFClient, StartWorkflowExecutionCommand } from "@aws-sdk/client-swf"; // ES Modules import
// const { SWFClient, StartWorkflowExecutionCommand } = require("@aws-sdk/client-swf"); // CommonJS import
const client = new SWFClient(config);
const input = { // StartWorkflowExecutionInput
  domain: "STRING_VALUE", // required
  workflowId: "STRING_VALUE", // required
  workflowType: { // WorkflowType
    name: "STRING_VALUE", // required
    version: "STRING_VALUE", // required
  },
  taskList: { // TaskList
    name: "STRING_VALUE", // required
  },
  taskPriority: "STRING_VALUE",
  input: "STRING_VALUE",
  executionStartToCloseTimeout: "STRING_VALUE",
  tagList: [ // TagList
    "STRING_VALUE",
  ],
  taskStartToCloseTimeout: "STRING_VALUE",
  childPolicy: "TERMINATE" || "REQUEST_CANCEL" || "ABANDON",
  lambdaRole: "STRING_VALUE",
};
const command = new StartWorkflowExecutionCommand(input);
const response = await client.send(command);
// { // Run
//   runId: "STRING_VALUE",
// };

StartWorkflowExecutionCommand Input

Parameter
Type
Description
domain
Required
string | undefined

The name of the domain in which the workflow execution is created.

The specified string must not contain a : (colon), / (slash), | (vertical bar), or any control characters (u0000-u001f | u007f-u009f). Also, it must not be the literal string arn.

workflowId
Required
string | undefined

The user defined identifier associated with the workflow execution. You can use this to associate a custom identifier with the workflow execution. You may specify the same identifier if a workflow execution is logically a restart of a previous execution. You cannot have two open workflow executions with the same workflowId at the same time within the same domain.

The specified string must not contain a : (colon), / (slash), | (vertical bar), or any control characters (u0000-u001f | u007f-u009f). Also, it must not be the literal string arn.

workflowType
Required
WorkflowType | undefined

The type of the workflow to start.

childPolicy
ChildPolicy | undefined

If set, specifies the policy to use for the child workflow executions of this workflow execution if it is terminated, by calling the TerminateWorkflowExecution action explicitly or due to an expired timeout. This policy overrides the default child policy specified when registering the workflow type using RegisterWorkflowType.

The supported child policies are:

  • TERMINATE – The child executions are terminated.

  • REQUEST_CANCEL – A request to cancel is attempted for each child execution by recording a WorkflowExecutionCancelRequested event in its history. It is up to the decider to take appropriate actions when it receives an execution history with this event.

  • ABANDON – No action is taken. The child executions continue to run.

A child policy for this workflow execution must be specified either as a default for the workflow type or through this parameter. If neither this parameter is set nor a default child policy was specified at registration time then a fault is returned.

executionStartToCloseTimeout
string | undefined

The total duration for this workflow execution. This overrides the defaultExecutionStartToCloseTimeout specified when registering the workflow type.

The duration is specified in seconds; an integer greater than or equal to 0. Exceeding this limit causes the workflow execution to time out. Unlike some of the other timeout parameters in Amazon SWF, you cannot specify a value of "NONE" for this timeout; there is a one-year max limit on the time that a workflow execution can run.

An execution start-to-close timeout must be specified either through this parameter or as a default when the workflow type is registered. If neither this parameter nor a default execution start-to-close timeout is specified, a fault is returned.

input
string | undefined

The input for the workflow execution. This is a free form string which should be meaningful to the workflow you are starting. This input is made available to the new workflow execution in the WorkflowExecutionStarted history event.

lambdaRole
string | undefined

The IAM role to attach to this workflow execution.

Executions of this workflow type need IAM roles to invoke Lambda functions. If you don't attach an IAM role, any attempt to schedule a Lambda task fails. This results in a ScheduleLambdaFunctionFailed history event. For more information, see https://docs.aws.amazon.com/amazonswf/latest/developerguide/lambda-task.html  in the Amazon SWF Developer Guide.

tagList
string[] | undefined

The list of tags to associate with the workflow execution. You can specify a maximum of 5 tags. You can list workflow executions with a specific tag by calling ListOpenWorkflowExecutions or ListClosedWorkflowExecutions and specifying a TagFilter.

taskList
TaskList | undefined

The task list to use for the decision tasks generated for this workflow execution. This overrides the defaultTaskList specified when registering the workflow type.

A task list for this workflow execution must be specified either as a default for the workflow type or through this parameter. If neither this parameter is set nor a default task list was specified at registration time then a fault is returned.

The specified string must not contain a : (colon), / (slash), | (vertical bar), or any control characters (u0000-u001f | u007f-u009f). Also, it must not be the literal string arn.

taskPriority
string | undefined

The task priority to use for this workflow execution. This overrides any default priority that was assigned when the workflow type was registered. If not set, then the default task priority for the workflow type is used. Valid values are integers that range from Java's Integer.MIN_VALUE (-2147483648) to Integer.MAX_VALUE (2147483647). Higher numbers indicate higher priority.

For more information about setting task priority, see Setting Task Priority  in the Amazon SWF Developer Guide.

taskStartToCloseTimeout
string | undefined

Specifies the maximum duration of decision tasks for this workflow execution. This parameter overrides the defaultTaskStartToCloseTimout specified when registering the workflow type using RegisterWorkflowType.

The duration is specified in seconds, an integer greater than or equal to 0. You can use NONE to specify unlimited duration.

A task start-to-close timeout for this workflow execution must be specified either as a default for the workflow type or through this parameter. If neither this parameter is set nor a default task start-to-close timeout was specified at registration time then a fault is returned.

StartWorkflowExecutionCommand Output

Parameter
Type
Description
$metadata
Required
ResponseMetadata
Metadata pertaining to this request.
runId
string | undefined

The runId of a workflow execution. This ID is generated by the service and can be used to uniquely identify the workflow execution within a domain.

Throws

Name
Fault
Details
DefaultUndefinedFault
client

The StartWorkflowExecution API action was called without the required parameters set.

Some workflow execution parameters, such as the decision taskList, must be set to start the execution. However, these parameters might have been set as defaults when the workflow type was registered. In this case, you can omit these parameters from the StartWorkflowExecution call and Amazon SWF uses the values defined in the workflow type.

If these parameters aren't set and no default parameters were defined in the workflow type, this error is displayed.

LimitExceededFault
client

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.

OperationNotPermittedFault
client

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

TypeDeprecatedFault
client

Returned when the specified activity or workflow type was already deprecated.

UnknownResourceFault
client

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.

WorkflowExecutionAlreadyStartedFault
client

Returned by StartWorkflowExecution when an open execution with the same workflowId is already running in the specified domain.

SWFServiceException
Base exception class for all service exceptions from SWF service.