Im developer who is new to AWS.

While configuring step functions, I found there are some senarious that there could be multiple step functions instance executed because of timer I've set.

for the step function that I configured follows below process

1. wait 2 minute
2. execute lambda function

since there is timer in my step function, there could be some cases that, step function might invoked multiple times at a time.

the thing is that, I wan't to guarantee that on execution queue, only one step function in on.

so if any other step function gets invoked, while step function in on running(timing), I wan't to terminate step function that just got invoked. is there any way to list step functions that are executing?

CodePudding user response：

You can't prevent an execution from starting, but you can list the executions at the start of your Step Function, and exit early if a running execution is found.

The ListExecutions API lists the executions for a given state machine ARN. Call it in a Task, setting the statusFilter to RUNNING to return only in-progress executions. You'll get back a list of matching execution items. All you care about is whether the length > 0.

Finally, insert a Choice state. If there are running items, exit. If no running items, continue with the execution.