Step Functions are a serverless AWS service used for robustly chaining together various services (such as Lambda functions), using state machine logic for branching and loops.
When plugging the output of one state into the input of another, you may want to do some simple manipulations of the data. For example, you may query DynamoDB in the first task, to fetch a database row as a dictionary, then you want to extract a particular column from that row, to pass as part of the input to a Lambda function execution. Step Functions allows you to implement such manipulations natively, using a subset of JSONPath.
The exact behavior of these path arguments can be hard to remember, particularly the order of each one, what null means, and how multiple paths interact. Reading the documentation to figure out the nuance can be time consuming, or unclear. Creating and executing trivial step functions to figure this out by trial and error is time consuming. Furthermore since Pass states don't support all fields, you cannot easily test them all.
Fill out the fields below with the input you want to pass to a state, and modify or disable each field as you see fit. The state output, raw task input, and intermediate fields will be updated instantly.
If you spot behavior that does not match official Step Function behavior, please submit an issue on GitHub .
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State Input Payload:
This is the raw input to the state, which comes from the output of the previous state.
Type your input here.