release-branches.yml

# release-branches.yml
#
# Checks if a PR is targeting a client or server release branch or not, and uploads a CI artifact containing the
# results, along with the PR number. This allows downstream workflows, such as release-approval, to be triggered by the
# completion of this workflow and take further action based on the target branch.

name: release-branches
on:
  pull_request:
    types:
      # This is triggered when the PR is opened. This is not strictly needed since the PR approval state is really
      # what's evaluated. However, running the job on PR open causes an immediate failure which will make it clearer to
      # the PR author what they need to do to unblock the merge.
      - opened

      # This is triggered when the PR branch has new commits pushed to it.
      - synchronize

      # This is triggered when the base branch changes; handles the case where you open a PR against one branch
      # then change the base branch to a release branch.
      - edited
    branches:
      - release/client/**
      - release/server/**
      - test/release/**

  # This workflow needs to run on review changes because it evaluates the review state.
  pull_request_review:
    types:
      - submitted
      - dismissed

permissions:
  pull-requests: read

jobs:
  check_branch:
    name: Check target branch
    runs-on: ubuntu-latest
    outputs:
      # This output will be set to true if the target branch is a release branch; false otherwise.
      is_release_branch: ${{ steps.is-release-branch.outputs.is_release_branch || steps.not-release-branch.outputs.is_release_branch }}
    steps:
      - name: Target is a release branch
        id: is-release-branch
        if: |
          startsWith(github.event.pull_request.base.ref, 'release/client/') ||
          startsWith(github.event.pull_request.base.ref, 'release/server/') ||
          startsWith(github.event.pull_request.base.ref, 'test/release/')
        run: |
          echo "is_release_branch=true" >> $GITHUB_OUTPUT
          echo ":ship: Release branch detected" >> $GITHUB_STEP_SUMMARY
      - name: Target is not a release branch
        id: not-release-branch
        if: |
          !(startsWith(github.event.pull_request.base.ref, 'release/client/') ||
          startsWith(github.event.pull_request.base.ref, 'release/server/') ||
          startsWith(github.event.pull_request.base.ref, 'test/release/'))
        run: |
          echo "is_release_branch=false" >> $GITHUB_OUTPUT
          echo ":no_entry_sign: No release branch detected" >> $GITHUB_STEP_SUMMARY

  save_metadata:
    name: Save PR details
    needs: check_branch
    runs-on: ubuntu-latest
    steps:
      - name: Create artifacts folder
        run: mkdir -p ./artifacts

      - name: Save PR number
        run: echo ${{ github.event.pull_request.number }} > ./artifacts/pr

      - name: Save is_release_branch
        run: echo ${{ needs.check_branch.outputs.is_release_branch }} > ./artifacts/is_release_branch

      - name: Upload artifact
        # release notes: https://github.com/actions/upload-artifact/releases/tag/v4.4.0
        uses: actions/upload-artifact@50769540e7f4bd5e21e526ee35c689e35e0d6874 # ratchet:actions/upload-artifact@v4.4.0
        with:
          name: release-branch-pr-metadata
          path: ./artifacts
          retention-days: 3