release-drafter.yaml

name: Release Drafter

on:
  push:
    branches:
      # we only want to draft release notes for the base version,
      # e.g. for releases/v0.18, we draft v0.18.0 for all RCs
      # this means that we explicitly don't want to draft release notes for releases/v0.18.0 or releases/v0.18.1
      - 'releases/v[0-9]+.[0-9]+'

permissions:
  contents: read
  # The release-drafter action adds PR titles to the release notes once these are merged to main.
  # A draft release is kept up-to-date listing the changes for the next minor or patch release version for that branch.
jobs:
  release-version:
    name: Release Version
    uses: ./.github/workflows/release-version.yaml
    with:
      # the draft release notes do not need to be done by release candidate
      # instead we can continously maintain them throughout the candidates
      release_candidate: false
    permissions:
      contents: read
      repository-projects: read
  update_release_draft:
    needs: release-version
    permissions:
      contents: write
    runs-on: ubuntu-latest
    env:
      RELEASE_VERSION: ${{ needs.release-version.outputs.version }}
    steps:
      - name: Generate token
        id: generate_token
        uses: tibdex/github-app-token@v2
        with:
          app_id: ${{ secrets.OCMBOT_APP_ID }}
          private_key: ${{ secrets.OCMBOT_PRIV_KEY }}
      - name: Checkout
        uses: actions/checkout@v4
        with:
          fetch-depth: 0
          fetch-tags: true
      - name: Setup Release with gh
        env:
          COLLAPSE_THRESHOLD: 5
          REF: ${{ github.ref }}
          REPO: ${{ github.repository }}
          GH_TOKEN: ${{ steps.generate_token.outputs.token }}
        run: |
          # generate the release notes based on the last previous tag.
          # match only a valid semver tag.
          # also do not match for the cutoff tag for the release branch.
          # Example: If we are in releases/v0.18, we don't want to match v0.18 as the cutoff tag.
          # Instead we want to match the one before that, which would be v0.17.
          # That would generate us the notes from
          # v0.17 to HEAD, which is what we want.
          # 
          # Implementors Note:
          # ##*\/ removes everything before the last / in the ref,
          # e.g. refs/heads/releases/v0.18 -> v0.18
          previous_tag=$(git describe HEAD --abbrev=0 --tags --match "v*" --exclude "${REF##*\/}")
          
          if [[ -z $previous_tag ]]; then
            echo "No previous tag found, cannot generate release notes"
            exit 1
          fi
          
          echo "Generating release notes for ${{env.RELEASE_VERSION}} starting from ${previous_tag} to HEAD"
          
          notes=$(\
             gh api  \
               --method POST \
               -H "Accept: application/vnd.github+json" \
               -H "X-GitHub-Api-Version: 2022-11-28" \
               /repos/${REPO}/releases/generate-notes \
               -f "tag_name=${{env.RELEASE_VERSION}}" \
               -f "target_commitish=${{ github.ref }}" \
               -f "previous_tag_name=${previous_tag}" \
               -f "configuration_file_path=.github/config/release.yml" \
               -q .body \
             )
          
          if [[ -z "${notes}" ]]; then
            echo "No release notes generated from API, failed"
            exit 1
          fi
          
          echo "Auto-Collapsing release notes to reduce size"
          echo "${notes}" > $RUNNER_TEMP/release_notes.md
          bash hack/collapse/auto_collapse.sh $RUNNER_TEMP/release_notes.md $RUNNER_TEMP/release_notes_processed.md ${{ env.COLLAPSE_THRESHOLD }}
          notes=$(cat $RUNNER_TEMP/release_notes_processed.md)
          
          echo "Release Notes generated for ${{env.RELEASE_VERSION}}:"
          echo "${notes}"
          
          echo "Verifying if release ${{env.RELEASE_VERSION}} already exists"
          if [[ -z $(gh release list -R ${REPO} --json name -q '.[] | select(.name == "${{env.RELEASE_VERSION}}")') ]]; then
            echo "Release ${{env.RELEASE_VERSION}} does not exist yet, creating from scratch"
            gh release create ${{env.RELEASE_VERSION}} \
              --title "${{env.RELEASE_VERSION}}" \
              --notes "${notes}" \
              --draft \
              --latest=false \
              --target ${{ github.ref }} \
              -R ${REPO}
          else
            echo "Release ${{env.RELEASE_VERSION}} already exists, updating existing..."
            gh release edit ${{env.RELEASE_VERSION}} \
              --notes "${notes}" \
              -R ${REPO}
          fi