pr_build_diff_dockers.yml

name: Pull Request Image Creation

on:
  pull_request:
    paths:
      - "**/Dockerfile"

jobs:
  changed-dockerfiles:
    name: Get Changed Dockerfiles Matrix
    runs-on: ubuntu-22.04
    outputs:
      matrix: ${{ steps.set-matrix.outputs.matrix }}
    steps:
      - id: checkout
        uses: actions/checkout@v3
        name: Checkout Repo
        with:
          fetch-depth: 0
      - id: changed-files-docker
        uses: tj-actions/changed-files@v41
        name: Get Changed Dockerfiles
        with:
          files: |
            **/Dockerfile
      - id: set-matrix
        name: Changed Dockerfiles String to Matrix
        run: |
          # From a space separated list of files, split by space, and set grandparent/parent dirnames as image/tag
          # Image names are always lowercase!
          # If no version directory exists, default to latest
          # "BANANA/1.0/Dockerfile panda/2.1/Dockerfile gatk/Dockerfile" -> [{"path":"./BANANA/1.0", "image":"banana", "tag":"1.0"}, {"path": "./panda/2.1", "image":"panda", "tag":"2.1"}, {"path": "gatk", "image":"gatk", "tag":"latest"}]
          MATRIX=$(echo ${{ steps.changed-files-docker.outputs.all_changed_files }} | jq -Rr 'split(" ") | map(rtrimstr("/Dockerfile")) | map({"path": ., "image": (. | split("/")[0] | ascii_downcase), "tag": (. | split("/")[1] // "latest")}) | @json')
          echo "matrix=$MATRIX" >> $GITHUB_OUTPUT
  build-dockerfiles:
    name: Build ${{ matrix.image }}:${{ matrix.tag }}
    needs: changed-dockerfiles
    runs-on: ubuntu-22.04
    strategy:
      matrix:
        include: ${{ fromJSON(needs.changed-dockerfiles.outputs.matrix) }}
    steps:
      - id: docker-buildx-setup
        name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v2
      - id: test-build
        name: Test Build Dockerfile
        uses: docker/build-push-action@v4
        with:
          context: "{{defaultContext}}:${{ matrix.path }}"