Step Functions

Question 1

Three patterns for integrating Step Functions with an AWS Service

Answer 1

1. Request a Response (Default): Lambda, SNS
2. Run a Job (Wait for Completion): Asynch: ECS tasks, Glue Jobs, Batch
3. Callback: Call a Service with a Task Token. When the service is done working, it can return the Token with a “SendTaskSuccess” or “SendTaskFailure” API call.

Question 2

What happens when a SF State reports an Error?

Answer 2

1. First looks for a “retry”
2. If none, or retry fails, look to “CATCH” array
   CATCH options include retry, log the error, send to a defined recovery state

Question 3

Must every Step Functions State have a “Next” field? Can they have more than one?

Answer 3

Yes, at least one. Those States with a “Choice” will have a “Next” option corresponding to each possible choice.