Idempotency Support (FINERACT-1420)

[ptuomola]

Description

Rebased version of #1951

Checklist

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[avikganguly01]

@ptuomola @IOhacker (cc: @fynmanoj) : If there's anything that we can do to help with idempotency, let us know!

[awasum]

I think what is left to be done is to reopen a PR for this..Fix merge conflicts and test to make sure it works. This might be useful for someone. I think no one is working on this at the moment.

[ptuomola]

The two things I think would be good to address / test are:

1. Backward compatibility: I don't think we want to add a new mandatory parameter to every single API signature. It would be better if the parameter was optional, and everything would work as-is if the parameter is not passed in
2. Optionality: I don't think everyone wants to set up and manage a new Redis database just to support this feature. So it should be possible to switch this on / off depending on whether this feature is required or not

[galovics]

@ptuomola just FYI, I'm going to tackle this in a couple of weeks.