NIFI-4212 - RethinkDB Delete Processor

[mans2singh]

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[jvwing]

Reviewing...

[jvwing]

Overall, this looks good - tests pass, integration tests pass, refactoring of integration test credentials is nice, code looks good. In my basic testing, it deleted objects from RethinkDB just fine. I have a few questions about the Return old Changes from the delete option, and how it is processed. I am not very familiar with RethinkDB, so I had to check the delete docs on how it works. I have no practical experience using this option.

• Instead of a true/false dropdown list, you made this a free text field supporting expression language. May I ask why? I think it would be easier to edit if we did, and easier to understand if we made the options more explanatory ("Capture changes as FlowFile content", "Do not capture changes", or something like that).
• If the option is true, the processor writes the changes to the attribute rethinkdb.delete.changes, the changes are also contained in the entire raw attribute rethinkdb.delete.result attribute, and finally the changes are written to the flowfile content. Do we need all of those?
• In the event that the deleted document is large, the attributes will be large, and potentially unusable due to truncation at 64KB.
• The modify provenance event is reported regardless of this setting. Shouldn't we only do that if a change is made?

[mans2singh]

Hi @jvwing - Thanks for your feedback and recommendations.

I used EL support for returning changed document attribute to give the use the flexibility to make the decision globally or per document. If you think this is not useful, I can change it.

You are right about the change document in the attribute and I've removed the related attributes.

Also, I've corrected modify provenance event to be invoked only when the flow file content is changed.

Please let me know if you have any other recommendations.

Thanks again.

Mans

[mans2singh]

Hi @jvwing - Please let me know if you have any other recommendations for this pull request. Thanks.

[jvwing]

Thanks for fixing those items, @mans2singh, I'll get this merged.

[mans2singh]

Thanks @jvwing