nf-core_modules/.github/workflows/docker.yml

name: Build Docker Images
on:
  push:
    # Only on pushes to master (after PRs are merged)
    branches: master
    # Only if a conda environment file or a docker build file has been updated
    paths:
      - tools/*/environment.yml
      - tools/*/Dockerfile

jobs:
  build_docker:
    runs-on: ubuntu-latest
    steps:

      # Check out the repo
      - uses: actions/checkout@v1

      # Find the tool wrappers that changed
      # Annoyingly, matrix can't take dynamic variables
      - name: Find changed tools
        run: |
          TOOLS=$( git diff --name-only HEAD~ | egrep -o 'tools\/[^\/]+\/' | sort | uniq | awk NF )
          echo "Tools that appear to have been updated:"
          echo $TOOLS
          # Save so that GitHub Actions can see this variable in the next step
          echo "::set-env name=TOOLS::$TOOLS"

      - name: Build images
        run: |
          echo "Running the docker build"
          echo $TOOLS
          for d in tools/*; do
            echo "In directory $d"
            for TOOL in $TOOLS; do
              echo "Tool is $TOOL"
              if echo $d/ | grep -q "$TOOL"; then
                cd "$GITHUB_WORKSPACE/$d"
                TOOLNAME=$(basename `pwd`)
                IMGNAME=docker.pkg.github.com/${GITHUB_REPOSITORY,,}/${TOOLNAME,,}:$GITHUB_SHA
                echo "Image name is: $IMGNAME"
                docker login -u ${{ github.actor }} -p ${{ secrets.GITHUB_TOKEN }} docker.pkg.github.com
                docker build -t $IMGNAME  .
                docker push $IMGNAME
              fi;
            done;
          done;