fix(otel): fix beatprocessor to honor when conditions

[mauri870]

Proposed commit message

The beat processor instantiated each processor by calling its New constructor directly, bypassing the conditional wrapping that processors.Namespace.Register applies on the standard libbeat path. The when field was unpacked into the config but silently dropped, so processors ran unconditionally.

Wrap each constructor with processors.NewConditional before invoking it so conditionals are honored, matching the behavior of standalone beats.

Checklist

• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have made corresponding change to the default configuration files
• I have added tests that prove my fix is effective or that my feature works. Where relevant, I have used the stresstest.sh script to run them under stress conditions and race detector to verify their stability.
• I have added an entry in ./changelog/fragments using the changelog tool.

How to test this PR locally

go test -count=1 -v -run '^TestCreateProcessor$' ./x-pack/otel/processor/beatprocessor/
go test -count=1 -tags=integration -v -run '^TestBeatProcessorWhenCondition$' ./x-pack/filebeat/tests/integration/

./script/stresstest.sh ./x-pack/otel/processor/beatprocessor '^TestCreateProcessor$' -p 4
2m10s: 17012 runs so far, 0 failures, 4 active

./script/stresstest.sh --tags integration ./x-pack/filebeat/tests/integration '^TestBeatProcessorWhenCondition$' -p 2
3m10s: 683 runs so far, 0 failures, 2 active

Related issues

• Closes beatprocessor OTel component ignores when conditions on processors #50549

[github-actions]

🤖 GitHub comments

Just comment with:

• run docs-build : Re-trigger the docs validation. (use unformatted text in the comment!)
• /test : Run the Buildkite pipeline.

[infra-vault-gh-plugin-prod]

Pinging @elastic/elastic-agent-data-plane (Team:Elastic-Agent-Data-Plane)

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Enterprise

Run ID: 487a5a52-77c2-4f01-918c-3d7743bf2a5a

📥 Commits

Reviewing files that changed from the base of the PR and between 1f65343 and 305a1ab.

📒 Files selected for processing (4)

• changelog/fragments/1778182489-honor-when-conditions-in-beatprocessor.yaml
• x-pack/filebeat/tests/integration/otel_test.go
• x-pack/otel/processor/beatprocessor/processor.go
• x-pack/otel/processor/beatprocessor/processor_test.go

---

📝 Walkthrough

Walkthrough

This PR fixes a bug where the OTel Beat processor was ignoring when conditions configured on sub-processors. The implementation refactors createProcessor to wrap processor constructors with OpenTelemetry Collector's processors.NewConditional, which evaluates conditional directives during processor instantiation. Unit tests validate wrapping behavior for positive matches, negative matches, and invalid conditions. An integration test confirms end-to-end behavior by configuring conditional add_fields operations and asserting fields are only added when their respective conditions match event content. A changelog entry documents the fix.

🚥 Pre-merge checks | ✅ 2

✅ Passed checks (2 passed)

Check name	Status	Explanation
Linked Issues check	✅ Passed	All code changes directly address issue #50549: wrapping Beat processor constructors with processors.NewConditional to honor when conditions.
Out of Scope Changes check	✅ Passed	All changes are scoped to fixing the when-conditions issue: processor.go refactoring, tests validating conditional behavior, and changelog entry.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

• 🛠️ Update Documentation: Commit on current branch
• 🛠️ Update Documentation: Create PR

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[github-actions]

@Mergifyio backport 8.19 9.3 9.4

[mergify]

backport 8.19 9.3 9.4

✅ Backports have been created

Details

• #50559 [8.19](backport #50555) fix(otel): fix beatprocessor to honor when conditions has been created for branch 8.19 but encountered conflicts

Cherry-pick of 7bbe8ee has failed:

On branch mergify/bp/8.19/pr-50555
Your branch is up to date with 'origin/8.19'.

You are currently cherry-picking commit 7bbe8ee6d.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	new file:   changelog/fragments/1778182489-honor-when-conditions-in-beatprocessor.yaml
	modified:   x-pack/filebeat/tests/integration/otel_test.go
	modified:   x-pack/otel/processor/beatprocessor/processor_test.go

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   x-pack/otel/processor/beatprocessor/processor.go

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

• #50560 [9.3](backport #50555) fix(otel): fix beatprocessor to honor when conditions has been created for branch 9.3 but encountered conflicts

Cherry-pick of 7bbe8ee has failed:

On branch mergify/bp/9.3/pr-50555
Your branch is up to date with 'origin/9.3'.

You are currently cherry-picking commit 7bbe8ee6d.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	new file:   changelog/fragments/1778182489-honor-when-conditions-in-beatprocessor.yaml
	modified:   x-pack/filebeat/tests/integration/otel_test.go
	modified:   x-pack/otel/processor/beatprocessor/processor_test.go

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   x-pack/otel/processor/beatprocessor/processor.go

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

• #50561 [9.4](backport #50555) fix(otel): fix beatprocessor to honor when conditions has been created for branch 9.4