docker.yml

name: Docker build

# This workflow is triggered by pull request actions such as opened, synchronized, or reopened
on:
  pull_request:
    types: [opened, synchronize, reopened]

jobs:
  # Defines a job to build (and optionally push) Docker images which we dont push the images in this workflow to avoid multiple builds on Docker hub 
  build:
    # Specifies that the job runs on the latest version of Ubuntu
    runs-on: ubuntu-latest
    
    # Uses a matrix strategy for running builds across multiple components in parallel
    strategy:
      matrix:
        component: ['api', 'keycloak'] # Components to be built

    # Environment variables to be used across all steps
    env:
      # Cleans the branch name to be used as Docker tag, using the commit SHA if the branch name is not available
      CLEAN_BRANCH_NAME: ${{ github.head_ref || github.ref_name }}
      DOCKER_TAG: ${{ (github.head_ref || github.ref_name) == '' && github.sha || (github.head_ref || github.ref_name) }}
    
    steps:
      # Step 1: Checks out the repository code including submodules
      - name: Checkout
        uses: actions/checkout@v4
        with:
          submodules: 'recursive' # Ensures all git submodules are checked out

      # Step 2: Sets up Docker Buildx for advanced Docker builds
      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3

      # Step 3: Logs in to DockerHub to allow pushing images (if needed)
      - name: Login to DockerHub
        uses: docker/login-action@v3
        with:
          username: ${{ secrets.DOCKERHUB_USERNAME }} # DockerHub username from secrets
          password: ${{ secrets.DOCKERHUB_TOKEN }} # DockerHub token from secrets

      # Step 4: Sanitizes the branch or commit SHA to be a valid Docker tag
      - name: Sanitize Reference Name for Docker Tag
        run: echo "DOCKER_TAG=$(echo $DOCKER_TAG | sed 's|/|-|g' | sed 's|[^a-zA-Z0-9_.-]|-|g')" >> $GITHUB_ENV

      # Step 5: Builds the Docker image but does not push it to DockerHub
      - name: Build
        uses: docker/build-push-action@v5
        with:
          context: ./${{ matrix.component }} # Specifies the directory as the Docker context
          file: ./${{ matrix.component }}/Dockerfile # Path to the Dockerfile
          push: false # Does not push the built image to DockerHub
          tags: usdotjpoode/jpo-conflictvisualizer-${{ matrix.component }}:${{ env.DOCKER_TAG }} # Tags the built image
          build-args: |
            MAVEN_GITHUB_TOKEN_NAME=${{ vars.MAVEN_GITHUB_TOKEN_NAME }}
            MAVEN_GITHUB_TOKEN=${{ secrets.MAVEN_GITHUB_TOKEN }}
            MAVEN_GITHUB_ORG=${{ github.repository_owner }}
          secrets: |
            MAVEN_GITHUB_TOKEN: ${{ secrets.MAVEN_GITHUB_TOKEN }}
          cache-from: type=gha
          cache-to: type=gha,mode=max