[Transform] Adding null check to fix potential NPE

[AjeetNathawat]

if CompositeAggregation is null then it can cause NPE in extractResults so adding null check to avoid it

[hendrikmuhs]

Thanks for the contribution. See my comment, the listener has to be called.

Would you also be willing to contribute a unit test? You can take this method as example:

https://github.com/elastic/elasticsearch/blob/main/x-pack/plugin/transform/src/test/java/org/elasticsearch/xpack/transform/transforms/pivot/PivotTests.java#L233

It would be nice if you could add a new method called testPreview that covers your fix, the "null" and the "empty" case.

[AjeetNathawat]

Thanks for the contribution. See my comment, the listener has to be called.

Would you also be willing to contribute a unit test? You can take this method as example:

https://github.com/elastic/elasticsearch/blob/main/x-pack/plugin/transform/src/test/java/org/elasticsearch/xpack/transform/transforms/pivot/PivotTests.java#L233

It would be nice if you could add a new method called testPreview that covers your fix, the "null" and the "empty" case.

Sure I will create test case with the reference.

[elasticsearchmachine]

Pinging @elastic/ml-core (Team:ML)

[hendrikmuhs]

Thanks for the update, time to run all tests:

@elasticmachine test this please

[AjeetNathawat]

after looking at the logs it seems I made a blunder, let me modify my changelog as per the required enum and style check

[AjeetNathawat]

I've added the required UT, please do review

[hendrikmuhs]

@elasticmachine test this please

[hendrikmuhs]

@AjeetNathawat the easiest way to fix the checkstyle issues is to run spotlessApply, see https://github.com/elastic/elasticsearch/blob/main/CONTRIBUTING.md#java-language-formatting-guidelines

Before pushing the changes to your branch, please run precommit to execute all checks.

[AjeetNathawat]

I've done the formatting now and ran the precommit task its successful now, thanks for pointing it out

[AjeetNathawat]

Hello @przemekwitek Thanks for the suggestion, I've addressed your comment.

[przemekwitek]

LGTM

[elasticsearchmachine]

💔 Backport failed

Status	Branch	Result
❌	7.17	Commit could not be cherrypicked due to conflicts
✅	8.8
✅	8.9

You can use sqren/backport to manually backport by running backport --upstream elastic/elasticsearch --pr 96785

[przemekwitek]

💚 All backports created successfully

Status	Branch	Result
✅	7.17

Questions ?

Please refer to the Backport tool documentation