release.yml

---
name: Release

on:
  workflow_run:
    types:
      - completed
    workflows:
      - 'ci'
jobs:
  docker:
    runs-on: ubuntu-latest
    if: ${{ github.event.workflow_run.conclusion == 'success' && contains(github.event.workflow_run.head_branch, 'release/') }}
    steps:
      - name: Get tag
        run: |
          branch=${{github.event.workflow_run.head_branch}}
          echo '::set-output name=tag::'${branch#release/}
        id: get-tag-step

      - name: "Checkout"
        uses: actions/checkout@v2

      - name: "Set up Docker Buildx"
        uses: docker/setup-buildx-action@v1

      - name: "Login to GitHub Container Registry"
        uses: docker/login-action@v1
        with:
          registry: ghcr.io
          username: ${{ github.repository_owner }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: "Build and push"
        uses: docker/build-push-action@v2
        with:
          file: Dockerfile
          context: .
          push: true
          tags: "ghcr.io/${{ github.repository_owner }}/${{ github.event.repository.name }}:${{ steps.get-tag-step.outputs.tag }}"