# Workflow to create an auto-buildable release periodically.
#
# Releases created with automation credentials don't trigger workflows.
# Therefore a token `secrets.RELEASE_TOKEN` must exist with public_repo scope.
name: Periodic release
on:
  # Run weekly on sunday at 21:37 UTC (arbitrary)
  schedule:
  - cron: '37 21 * * SUN'
  # Allow triggering manually:
  # curl -XPOST -d '{"event_type":"periodic"}' \
  #  "-HAuthorization: Bearer <token>" \
  #   https://api.github.com/repos/clangd/clangd/dispatches
  repository_dispatch: { types: periodic }
jobs:
  # Choose the commit to build a release from.
  #
  # We want to avoid unbuildable revisions: choose the last green from CI.
  # FIXME: the criteria should be some consistent set of buildbots passing.
  pick:
    name: Create draft release
    runs-on: ubuntu-latest
    steps:
    - name: Clone scripts
      uses: actions/checkout@v2
    - name: Pick last successful commit
      id: pick
      uses: clangd/actions/.github/actions/pick@v0.1.0
      with:
        repo: llvm/llvm-project
        token: ${{ secrets.GITHUB_TOKEN }}
    - name: Compute release info
      run: |
        echo "RELEASE_COMMIT_SHORT=$(printf '%.12s' ${{ steps.pick.outputs.sha }})" >> $GITHUB_ENV
        echo "RELEASE_DATE=$(date -u +%Y%m%d)" >> $GITHUB_ENV
    - name: Create release
      uses: actions/create-release@master
      id: release
      env: { GITHUB_TOKEN: "${{ secrets.RELEASE_TOKEN }}" }
      with:
        tag_name: snapshot_${{ env.RELEASE_DATE }}
        release_name: ${{ env.RELEASE_DATE }} @${{ env.RELEASE_COMMIT_SHORT }}
        body: |
          Unstable snapshot of clangd on ${{ env.RELEASE_DATE }}.

          Built from llvm/llvm-project@${{ steps.pick.outputs.sha }}.
        prerelease: true
        # It would be nice to use draft releases, to hide them from users.
        # But drafts don't fire events to trigger the autobuild workflow.
        # Instead, that workflow marks the release as draft until it's built.
        # As a result, the empty release will be briefly visible to users.
        draft: false