auto-release.yml

name: Auto Release

# Triggers when a version bump commit lands on main (from a merged release PR)
on:
  push:
    branches: [main]
    paths:
      - 'pyproject.toml'

permissions:
  contents: write
  actions: write

jobs:
  check:
    runs-on: ubuntu-latest
    outputs:
      should_release: ${{ steps.check.outputs.should_release }}
      version: ${{ steps.check.outputs.version }}
      tag: ${{ steps.check.outputs.tag }}
      is_prerelease: ${{ steps.check.outputs.is_prerelease }}
    steps:
      - name: Check if this is a version bump commit
        id: check
        env:
          COMMIT_MSG: ${{ github.event.head_commit.message }}
        run: |
          if [[ "$COMMIT_MSG" =~ ^chore:\ bump\ version\ to\ ([0-9]+\.[0-9]+\.[0-9]+(rc[0-9]+)?) ]]; then
            VERSION="${BASH_REMATCH[1]}"
            echo "should_release=true" >> "$GITHUB_OUTPUT"
            echo "version=$VERSION" >> "$GITHUB_OUTPUT"
            echo "tag=v$VERSION" >> "$GITHUB_OUTPUT"
            if [[ "$VERSION" =~ rc ]]; then
              echo "is_prerelease=true" >> "$GITHUB_OUTPUT"
            else
              echo "is_prerelease=false" >> "$GITHUB_OUTPUT"
            fi
            echo "Detected release: $VERSION"
          else
            echo "should_release=false" >> "$GITHUB_OUTPUT"
            echo "Not a version bump commit, skipping."
          fi

  create-release:
    needs: check
    if: needs.check.outputs.should_release == 'true'
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Check tag doesn't already exist
        run: |
          if git ls-remote --tags origin | grep -q "refs/tags/${{ needs.check.outputs.tag }}$"; then
            echo "Tag ${{ needs.check.outputs.tag }} already exists!"
            exit 1
          fi

      - name: Create GitHub Release
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          PRERELEASE_FLAG=""
          NOTES_START_FLAG=""
          if [[ "${{ needs.check.outputs.is_prerelease }}" == "true" ]]; then
            PRERELEASE_FLAG="--prerelease"
          else
            # Span notes from the previous stable release so changes that
            # landed in intermediate RCs are included in the stable changelog.
            PREV_STABLE="$(gh release list --exclude-pre-releases --exclude-drafts --limit 1 --json tagName --jq '.[0].tagName')"
            if [[ -n "$PREV_STABLE" ]]; then
              NOTES_START_FLAG="--notes-start-tag $PREV_STABLE"
            fi
          fi

          gh release create "${{ needs.check.outputs.tag }}" \
            --target "${{ github.sha }}" \
            --title "${{ needs.check.outputs.tag }}" \
            --generate-notes \
            $NOTES_START_FLAG \
            $PRERELEASE_FLAG

      - name: Trigger downstream workflows
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          gh workflow run release.yml -f tag=${{ needs.check.outputs.tag }}
          gh workflow run publish.yml