feat(appset): Support various merge strategies for merge generator

[sonamkshenoy]

Support for various merge strategies in merge generator. Includes: left-join, left-join-uniq, inner-join, inner-join-uniq, full-join, full-join-uniq

This PR also allows more than one parameter sets to have the same merge key in the base generator

Fixes #11952, #12837, #14560

[sonamkshenoy]

@crenshaw-dev Please review. Thank you!!

Also, do you think it's better to have a more intuitive name for the flag? Something like allowNonUniqBaseMergeKeys

[crenshaw-dev]

Actually, I think we should probably have a string field called mergeMode to accommodate new modes as they come up.

[darkradish]

Hello ! This Pull request can make applicationSets very powerfull ! @sonamkshenoy do you work at it ? do you want some help ?

[sonamkshenoy]

Hey @darkradish Thank you! Yes, I'm actively working on it. Thanks for your offer to help; I'm actually waiting for a review from one of the maintainers. :)

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 72.22222% with 20 lines in your changes are missing coverage. Please review.

Project coverage is 49.50%. Comparing base (d595550) to head (c35ac69). Report is 185 commits behind head on master.

:exclamation: Current head c35ac69 differs from pull request most recent head 1548125. Consider uploading reports for the commit 1548125 to get more accurate results

Files	Patch %	Lines
applicationset/generators/merge.go	72.22%	13 Missing and 7 partials :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #16080      +/-   ##
==========================================
+ Coverage   49.48%   49.50%   +0.01%     
==========================================
  Files         271      271              
  Lines       47728    47774      +46     
==========================================
+ Hits        23620    23651      +31     
- Misses      21773    21782       +9     
- Partials     2335     2341       +6     

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[ptr1120]

Are there any plans to merge this awesome feature?

[Boeller666]

Same question here... will this feature be merged in the near future? This would help a lot!

[alancaldelas]

I am also very interested in this

[ProbstenHias]

Hi, what is the progress here, I would love to see this working as we have the need for exactly this feature. I could help out with this if you want.

[Boeller666]

@sonamkshenoy If you would do the signoff for your commits we would be one step further towards getting this cool feature into prod. If you might have problems with signing old commits, you could follow this link

[reedjosh]

@sonamkshenoy If you would do the signoff for your commits we would be one step further towards getting this cool feature into prod. If you might have problems with signing old commits, you could follow this link

@sonamkshenoy we could really use this feature.

It seems the final commit is signed. Could this be squashed and rebased?