name: 'Sample App Push'
description: 'Pushes a containerized sample app to Docker'
inputs:
  app-dir:
    description: 'relative path to the app directory'
    required: true
  docker-registry:
    description: 'docker registry'
    required: false
  docker-username:
    description: 'docker username'
    required: true
  docker-password:
    description: 'docker password'
    required: true
  docker-images:
    description: 'csv of docker images to push'
    required: true
  docker-images-override:
    description: 'csv of docker image tags to use when pushing (parallel array to docker-images)'
    required: false
runs:
  using: "composite"
  steps:

    - name: Login Dockerhub
      uses: docker/login-action@v1
      with:
        registry: ${{ inputs.docker-registry }}
        username: ${{ inputs.docker-username }}
        password: ${{ inputs.docker-password }}

    - name: Push images to Dockerhub
      env:
        DOCKER_REGISTRY: ${{ inputs.docker-registry }}
        DOCKER_IMAGES: ${{ inputs.docker-images }}
        DOCKER_IMAGES_OVERRIDE: ${{ inputs.docker-images-override }}
      working-directory: ${{ inputs.app-dir }}
      shell: bash
      run: |
        # read the images into arrays
        read -r -a images <<< "$DOCKER_IMAGES"
        read -r -a imagesOverride <<< "$DOCKER_IMAGES_OVERRIDE"
        
        # validate lengths if override specified
        numImages=${#images[@]}
        numImagesOverride=${#imagesOverride[@]}
        if [[ $numImagesOverride -gt 0 && $numImages -ne $numImagesOverride ]]; then
          echo "when 'docker-images-override' is specified it must be the same length as 'docker-images'"
          exit 1
        fi
        # determine the target images name based on registry and override
        for idx in "${!images[@]}"
        do
          # use override if specified
          if [[ $numImagesOverride -gt 0 ]]; then
            image="${imagesOverride[idx]}"
          else
            image="${images[idx]}"
          fi      
          # pre-pend registry if specified
          if [[ "$DOCKER_REGISTRY" != "" ]]; then
            image="$DOCKER_REGISTRY/$image"
          fi
        
          # tag the original image if it has changed (override and/or registry)
          originalImage="${images[idx]}"
          if [[ "$image" != "$originalImage" ]]; then
            docker tag ${originalImage} ${image}
          fi
          docker push ${image}
          echo "::info ::published ${image}"
        done