NIFI-4559: Add non-zero status relationship to ExecuteStreamCommand

[mattyb149]

Sorry about the whitespace changes, I must have slightly different (but still compliant) formatting settings in my IDE.

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[markap14]

I wonder if this is necessary? The processor doesn't currently penalize anything. I think it may make sense to always penalize when sending to the new relationship and the user has the ability to just set Penalty Duration to "0 sec" if they don't want to penalize.

[mattyb149]

Good point. That property is only to retain current behavior. If they leave the defaults, then once they upgrade, their "failed" flow files will now start to be penalized. That may be acceptable since the user will need to route or terminate that new relationship anyway, so I could add to the doc that flow files routed to that relationship will be penalized, which should imply that they might need to change the Penalty Duration setting?

[MikeThomsen]

Checked out the branch and it ran as intended against a simple python script that used sys.exit(1)

+1

[MikeThomsen]

@mattyb149 As mentioned, I tried this out and got it to work. So I see no reason it cannot be merged.

[mattyb149]

@MikeThomsen Thank you for your review! I think I tested it fairly well also, so with your +1 I can merge this in.