Though I have not tried it, I suspect this to be possible.
ListS3 typically provides the input of FetchS3, if you want to imitate this, consider manually running ListS3 and carefully inspecting the flowfiles it creates. (Content and attributes/metadata).
From here you can probably simulate the flowfile e.g. with generateflowfile to test if you can use FetchS3 without ListS3.
If this succeeds, you can update your flow to make sure it provides the right inputs.
- Dennis Jaheruddin
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