How to wait for multiple parallel tasks to all finish first to proceed to next state in AWS Step Function?

Question

I'm trying to build a process like this: In state1, it will trigger 10 lambdas, and only when ALL those 10 lambda respond/ or call callback with taskToken, it will then proceed to next state2. How to design this process?

Answer 1

This is a perfect scenario for the Map state. You can pass in an array of lambda function names, then add a Lambda task and use the Parameters block to set the function dynamically. And if you want them to run one at a time instead of in parallel, you can set MaxConcurrency.