startExecution

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 named myStateMachine.arn:partition:states:region:account-id:stateMachine:myStateMachine/mapStateLabelIf 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:<partition>:states:<region>:<account-id>: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:<partition>:states:<region>:<account-id>:stateMachine:<myStateMachine>

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.