[derrickaw]

1. Add a PR size label so reviewers and users can see what size PRs are from the PR main page.
2. Use a third-party library allowed by Apache infra to do the labeling.

[derrickaw]

/gemini review

[github-actions]

📋 Review Summary

This PR introduces a GitHub Actions workflow (pr-size-labeler.yml) that automatically calculates PR diff sizes (additions + deletions) and applies appropriate size/* labels. The workflow avoids checking out untrusted code on pull_request_target and passes workflow expressions safely via environment variables.

🔍 General Feedback

• Calling gh label create five times on every PR event adds 5 unnecessary GitHub API requests per workflow run, which can contribute to GITHUB_TOKEN rate limit exhaustion on a high-traffic repository like Apache Beam.
• Label matching uses grep -Fq without whole-line matching (-x), which can cause substring false positives if any prefix/suffix labels exist in the future.
• Consider adding a concurrency group per PR so rapid pushes (synchronize events) do not race when adding and removing size labels.

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[github-actions]

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[github-actions]

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[derrickaw]

assign set of reviewers

[github-actions]

Assigning reviewers:

R: @damccorm for label build.
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[damccorm]

Haven't done a thorough review, but could you help me understand the goal here?

GitHub already renders the diff size directly above the labels, so I'm not sure how much info this adds

[derrickaw]

Haven't done a thorough review, but could you help me understand the goal here?

GitHub already renders the diff size directly above the labels, so I'm not sure how much info this adds

Other Github repos have this feature and when looking through the PRs from the main PR page you can quickly tell what size the PRs are and maybe review those first without clicking on PR to determine how large the changes are.

Its a small workflow with little maintenance, but with added benefit. Thanks

[Abacn]

Thought about using a third party app, but then we have to get Apache Infra to approve

Have you checked if there is an existing Apache projects implementing PR sizes with third party Action? Ideally we can use one other than maintain our own; and we can put it into existing pr bot workflow (to just trigger one workflow per push)

[derrickaw]

Thought about using a third party app, but then we have to get Apache Infra to approve

Have you checked if there is an existing Apache projects implementing PR sizes with third party Action? Ideally we can use one other than maintain our own; and we can put it into existing pr bot workflow (to just trigger one workflow per push)

Found another Apache project - mynewt - that uses a third party action. Updated to that. Thanks.

[damccorm]

Haven't done a thorough review, but could you help me understand the goal here?
GitHub already renders the diff size directly above the labels, so I'm not sure how much info this adds

Other Github repos have this feature and when looking through the PRs from the main PR page you can quickly tell what size the PRs are and maybe review those first without clicking on PR to determine how large the changes are.

Its a small workflow with little maintenance, but with added benefit. Thanks

I'm fine adding this, particularly now that we've reafactored to use an external action. But the underlying principle I want us to be careful of is adding code that has limited value since code is a liability.