By using AWS re:Post, you agree to the Terms of Use
/Possible to have a single parameter receive its value conditionally?/

Possible to have a single parameter receive its value conditionally?


I have a parameter 'request_id' that I want to have get an ID from two different formats of JSON that get sent to the input of my step function task.

The first form looks like this:

{ "request_id": "abcde-abcd-abcde-abc" }

The second is in this form:

{ "request": { "id": "abcde-abcd-abcde-abc", }

Currently, I have a parameter which looks like

"request_id.$": "$.request_id"

but would like something that is equivalent to (this one does not work)

"request_id.$": "$.['request_id','']"

The step function task looks like this

"Processing Error": {
              "Type": "Task",
              "Resource": "${UpdateRequestStatus.Arn}",
              "Parameters": {
                "status": "ERROR",
                "status_reason": "Failed to process data.",
                "domain_name.$": "$.domain_name",
                "client_id.$": "$.client_id",
                *"request_id.$": "$.request_id"*
              "Next": "Processing Failed"

Is this possible within the step function or will I need to either split those two request id's up into two paths in my JSON or do it in a function?

1 Answers


I believe this capability is not possible through JsonPath.
I would suggest you normalize the input data to the state OR as you mentioned, possibly have a state prior to the task state that will handle these 2 conditions and normalize it before it reaches the task state.

answered 2 years ago

You are not logged in. Log in to post an answer.

A good answer clearly answers the question and provides constructive feedback and encourages professional growth in the question asker.

Guidelines for Answering Questions