NIFI-6047 Add DeduplicateRecords (combines 6047 and 6014)

[MikeThomsen]

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Enables X functionality; fixes bug NIFI-YYYY.

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[MikeThomsen]

@adamfisher FYSA

[MikeThomsen]

@mattyb149 thanks for taking a look. I'll try to carve out some time in the evening to address.

[github-actions]

We're marking this PR as stale due to lack of updates in the past few months. If after another couple of weeks the stale label has not been removed this PR will be closed. This stale marker and eventual auto close does not indicate a judgement of the PR just lack of reviewer bandwidth and helps us keep the PR queue more manageable. If you would like this PR re-opened you can do so and a committer can remove the stale tag. Or you can open a new PR. Try to help review other PRs to increase PR review bandwidth which in turn helps yours.

[adamfisher]

I would prefer not to see this go away. I put a lot of time into making it generic and robust. Really I just ran into problems near the end when I had to get it merged in properly and Mike is the git ninja. I thought this was almost across the finish line?

[ottobackwards]

@adamfisher that was an automated message

[ottobackwards]

@MikeThomsen?

[MikeThomsen]

I think it is close to being done, but it fell off everyone's radars (including @adamfisher). @ottobackwards you can pick up the review now if @mattyb149 is low on time :-D

[ottobackwards]

Left a couple of small comments. Also, I think for maintainability, it would be nice if there were some comments and javadoc in the processor, as to the overall logic/process, and what the methods are doing / returning.

[MikeThomsen]

Thanks @ottobackwards. I'll try to make some time to knock these out tomorrow.

[github-actions]

We're marking this PR as stale due to lack of updates in the past few months. If after another couple of weeks the stale label has not been removed this PR will be closed. This stale marker and eventual auto close does not indicate a judgement of the PR just lack of reviewer bandwidth and helps us keep the PR queue more manageable. If you would like this PR re-opened you can do so and a committer can remove the stale tag. Or you can open a new PR. Try to help review other PRs to increase PR review bandwidth which in turn helps yours.

[adamfisher]

If there is something I can do to get this across the finish line I would love to help. I'm just not familiar with the roadblocks I faced in the git process. I put a lot of work into it and I think it would be a very useful processor block for deduping records.

[MikeThomsen]

Revisiting this. @ottobackwards @mattyb149 @exceptionfactory going to work through any remaining comments and see if we can close this out this week.

[adamfisher]

Revisiting this. @ottobackwards @mattyb149 @exceptionfactory going to work through any remaining comments and see if we can close this out this week.

Thank you so much @MikeThomsen! Excited to have this processor block see the light of day. 🌞 🌞 🌞

[MikeThomsen]

DeduplicateRecords_TestWithCassandraDMC.xml.txt

Here is a test flow.

CREATE KEYSPACE nifi
      WITH REPLICATION = { 
       'class' : 'SimpleStrategy', 
       'replication_factor' : 1 
      };

use nifi;

create table map_cache (key blob, value blob, primary key(key));

docker run -p 9042:9042 --name nifi-cassandra cassandra:4

[MikeThomsen]

@mattyb149 @exceptionfactory @ottobackwards I think we're good new. See the attacked template and steps to setup Cassandra in docker to quickly test.

[mattyb149]

Using a DistributedMapCache client & server (rather than Cassandra, just to be different), I couldn't get any records/flowfiles on the duplicate relationship after sending 2 of the same flowfile into the DeduplicateRecords processor (with the config from your template above, Multiple Files e.g.). I had to enable the rest of the flow so the cache values would be populated by the PutDistributedMapCache processor. Is that intended? If so the docs should reflect that and if not, the processor itself should handle writing the cache identifier so no additional processor is needed, or perhaps it would at least be configurable.

[exceptionfactory]

Thanks for revisiting this pull request @MikeThomsen. Coming back to this after some time, I noted a few additional issues related to message digest handling and options, as well as a few other minor things related to logging and testing. Others may be able to provide additional feedback on general functionality, and I can take another look soon.

[MikeThomsen]

Good feedback. Will incorporate.

[MikeThomsen]

@mattyb149

I had to enable the rest of the flow so the cache values would be populated by the PutDistributedMapCache processor. Is that intended? If so the docs should reflect that and if not, the processor itself should handle writing the cache identifier so no additional processor is needed, or perhaps it would at least be configurable.

I'll update the docs. We can't have this processor updating the DMC because otherwise it's going to be such a thing upstream of the operations that need to complete before a DMC entry is written.

[mattyb149]

Most of the things I found were with non-ideal-path situations such as operator error :) , CS failures, etc. Otherwise this is looking and working well, it's getting close!

[MikeThomsen]

@exceptionfactory @ottobackwards @mattyb149 should be good to go now.

[MikeThomsen]

@exceptionfactory @mattyb149 any chance we could close this out?

[joewitt]

Please don't use plural form on processor naming.

DeduplicateRecord

[MikeThomsen]

@joewitt addressed your request.

[mattyb149]

+1 LGTM, tried with various happy and non-happy scenarios, verified the expected results. Thanks for sticking with this new feature! Merging to main