name: Docker
on:
  pull_request:
    paths:
      - .github/workflows/docker.yml
      - Dockerfile
  release:
    types:
      - published
jobs:
  ubuntu:
    runs-on: ubuntu-latest
    strategy:
      matrix:
        version: ["18.04", "20.04"]
    steps:
      - name: Checkout
        uses: actions/checkout@master
        with:
          fetch-depth: 0
      - name: Build Docker image
        run: docker build -t brew --build-arg=version=${{matrix.version}} .
      - name: Run brew test-bot
        run: docker run --rm brew brew test-bot
      - name: Deploy the tagged Docker image to GitHub
        if: startsWith(github.ref, 'refs/tags/')
        run: |
          docker login docker.pkg.github.com -u BrewTestBot -p ${{secrets.GITHUB_TOKEN}}
          v=${GITHUB_REF:10}
          docker tag brew "docker.pkg.github.com/homebrew/brew/ubuntu${{matrix.version}}:$v"
          docker push "docker.pkg.github.com/homebrew/brew/ubuntu${{matrix.version}}:$v"