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StartExecutionCommand
Starts a state machine execution.
A qualified state machine ARN can either refer to a Distributed Map state defined within a state machine, a version ARN, or an alias ARN.
The following are some examples of qualified and unqualified state machine ARNs:
-
The following qualified state machine ARN refers to a Distributed Map state with a label
mapStateLabel
in a state machine namedmyStateMachine
.arn:partition:states:region:account-id:stateMachine:myStateMachine/mapStateLabel
If you provide a qualified state machine ARN that refers to a Distributed Map state, the request fails with
ValidationException
. -
The following qualified state machine ARN refers to an alias named
PROD
.arn:
:states: : :stateMachine:myStateMachine:PROD If you provide a qualified state machine ARN that refers to a version ARN or an alias ARN, the request starts execution for that version or alias.
-
The following unqualified state machine ARN refers to a state machine named
myStateMachine
.arn:
:states: : :stateMachine:
If you start an execution with an unqualified state machine ARN, Step Functions uses the latest revision of the state machine for the execution.
To start executions of a state machine version , call StartExecution
and provide the version ARN or the ARN of an alias that points to the version.
StartExecution
is idempotent for STANDARD
workflows. For a STANDARD
workflow, if you call StartExecution
with the same name and input as a running execution, the call succeeds and return the same response as the original request. If the execution is closed or if the input is different, it returns a 400 ExecutionAlreadyExists
error. You can reuse names after 90 days.
StartExecution
isn't idempotent for EXPRESS
workflows.
Example Syntax
Use a bare-bones client and the command you need to make an API call.
import { SFNClient, StartExecutionCommand } from "@aws-sdk/client-sfn"; // ES Modules import
// const { SFNClient, StartExecutionCommand } = require("@aws-sdk/client-sfn"); // CommonJS import
const client = new SFNClient(config);
const input = { // StartExecutionInput
stateMachineArn: "STRING_VALUE", // required
name: "STRING_VALUE",
input: "STRING_VALUE",
traceHeader: "STRING_VALUE",
};
const command = new StartExecutionCommand(input);
const response = await client.send(command);
// { // StartExecutionOutput
// executionArn: "STRING_VALUE", // required
// startDate: new Date("TIMESTAMP"), // required
// };
StartExecutionCommand Input
Parameter | Type | Description |
---|
Parameter | Type | Description |
---|---|---|
stateMachineArn Required | string | undefined | The Amazon Resource Name (ARN) of the state machine to execute. The
|
input | string | undefined | The string that contains the JSON input data for the execution, for example: If you don't include any JSON input data, you still must include the two braces, for example: Length constraints apply to the payload size, and are expressed as bytes in UTF-8 encoding. |
name | string | undefined | Optional name of the execution. This name must be unique for your Amazon Web Services account, Region, and state machine for 90 days. For more information, see Limits Related to State Machine Executions in the Step Functions Developer Guide. If you don't provide a name for the execution, Step Functions automatically generates a universally unique identifier (UUID) as the execution name. A name must not contain:
To enable logging with CloudWatch Logs, the name should only contain 0-9, A-Z, a-z, - and _. |
traceHeader | string | undefined | Passes the X-Ray trace header. The trace header can also be passed in the request payload. |
StartExecutionCommand Output
Parameter | Type | Description |
---|
Parameter | Type | Description |
---|---|---|
$metadata Required | ResponseMetadata | Metadata pertaining to this request. |
executionArn Required | string | undefined | The Amazon Resource Name (ARN) that identifies the execution. |
startDate Required | Date | undefined | The date the execution is started. |
Throws
Name | Fault | Details |
---|
Name | Fault | Details |
---|---|---|
ExecutionAlreadyExists | client | The execution has the same Executions with the same |
ExecutionLimitExceeded | client | The maximum number of running executions has been reached. Running executions must end or be stopped before a new execution can be started. |
InvalidArn | client | The provided Amazon Resource Name (ARN) is not valid. |
InvalidExecutionInput | client | The provided JSON input data is not valid. |
InvalidName | client | The provided name is not valid. |
KmsAccessDeniedException | client | Either your KMS key policy or API caller does not have the required permissions. |
KmsInvalidStateException | client | The KMS key is not in valid state, for example: Disabled or Deleted. |
KmsThrottlingException | client | Received when KMS returns |
StateMachineDeleting | client | The specified state machine is being deleted. |
StateMachineDoesNotExist | client | The specified state machine does not exist. |
ValidationException | client | The input does not satisfy the constraints specified by an Amazon Web Services service. |
SFNServiceException | Base exception class for all service exceptions from SFN service. |