release.yaml

name: Release with Docker image to GHCR

on:
  push:
    tags:
      - 'v**'

jobs:
  release:
    runs-on: ubuntu-latest

    steps:
      - name: Checkout code
        uses: actions/checkout@v6

      - name: Verify tag points to a commit on main branch
        id: verify_branch
        run: |
          TAG_COMMIT=$(git rev-list -n 1 $GITHUB_REF)
          echo "Tag commit: $TAG_COMMIT"

          # Fetch main branch commit
          git fetch origin main
          MAIN_COMMIT=$(git rev-parse origin/main)
          echo "Main commit: $MAIN_COMMIT"

          # Check if TAG_COMMIT is ancestor of main commit
          if git merge-base --is-ancestor $TAG_COMMIT $MAIN_COMMIT; then
            echo "continue=true" >> $GITHUB_OUTPUT
          else
            echo "continue=false" >> $GITHUB_OUTPUT
          fi

      - name: Stop if tag is not on main branch
        if: steps.verify_branch.outputs.continue != 'true'
        run: |
          echo "Tag commit is not on main branch, skipping release."
          exit 0

      - name: lowercase repo
        run: |
          echo "REPO=${GITHUB_REPOSITORY,,}" >>${GITHUB_ENV}

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3

      - name: Log in to GitHub Container Registry
        uses: docker/login-action@v3
        with:
          registry: ghcr.io
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Build and push Docker image to GHCR
        uses: docker/build-push-action@v6
        with:
          context: .
          push: true
          tags: |
            ghcr.io/${{ env.REPO }}:${{ github.ref_name }}
            ghcr.io/${{ env.REPO }}:latest

      - name: Create GitHub Release
        uses: softprops/action-gh-release@v2
        with:
          tag_name: ${{ github.ref_name }}
          name: Release ${{ github.ref_name }}
          body: |
            Docker image pushed to GHCR:

            ```bash
            docker pull ghcr.io/${{ env.REPO }}:${{ github.ref_name }}
            ```