build.yml

name: Build and Push Docker Image

# Trigger workflow on tag pushes (e.g., v1.0.0, release-1.2.3)
on:
  push:
    tags:
      - '*'
    
jobs:
  # First job: Build root POM and jobs-core module
  # This job serves as the foundation for all other parallel jobs
  # It builds the root POM, builds jobs-core, and uploads Maven repository
  # All other jobs depend on this job and download the Maven repository from it
  root-pom-build-and-jobs-core:
    runs-on: ubuntu-latest
    outputs:
      # Output the Maven cache key for potential use by other jobs
      maven-cache-key: ${{ steps.cache-maven.outputs.cache-primary-key }}
    steps:
      # Step 1: Checkout the source code from the tag
      - uses: actions/checkout@v3

      # Step 2: Set up Java 11 environment for building
      # Uses Temurin distribution for better performance and reliability
      - name: Set up JDK11
        uses: actions/setup-java@v3
        with:
          java-version: '11'
          distribution: 'temurin'
          cache: 'maven'  # Additional Maven caching provided by setup-java

      # Step 3: Cache Maven dependencies to speed up builds
      # This caches the ~/.m2/repository directory between workflow runs
      # The cache key is based on the hash of all pom.xml files
      - name: Cache Maven packages
        id: cache-maven
        uses: actions/cache@v3
        with:
          path: ~/.m2/repository
          key: ${{ runner.os }}-maven-${{ hashFiles('**/pom.xml') }}
          restore-keys: |
            ${{ runner.os }}-maven-
      # Step 4: Build root POM and jobs-core module
      # This step performs a comprehensive build of the jobs-core module
      - name: Build root POM and jobs-core
        run: |
          # First, build only the root POM (parent project) without building modules
          # -N flag means "non-recursive" - only build the current project
          mvn clean install -N -DskipTests
          
          # Then build the jobs-core module
          cd jobs-core
          mvn clean install -DskipTests
      # Step 5: Upload Maven repository as artifact
      # This makes the built dependencies available to parallel jobs
      # All other jobs will download this to avoid rebuilding dependencies
      - name: Upload Maven local repository
        uses: actions/upload-artifact@v4.6.2
        with:
          name: maven-repo
          path: ~/.m2/repository
          retention-days: 1  # Keep for 1 day to allow for debugging


  # Final job: Build Docker image and push to registry
  # This job builds all modules and jobs-distribution, then creates Docker image
  # It only depends on the foundation job that provides the base Maven repository
  build-and-push-docker:
    needs: root-pom-build-and-jobs-core
    runs-on: ubuntu-latest
    steps:
      # Step 1: Checkout the source code (needed for Docker build context)
      - name: Checkout code
        uses: actions/checkout@v3

      # Step 2: Set up Java 11 environment
      - name: Set up JDK11
        uses: actions/setup-java@v3
        with:
          java-version: '11'
          distribution: 'temurin'
          cache: 'maven'

      # Step 2a: Set up specific Maven version for consistency
      - name: Set up Maven 3.8.7
        uses: s4u/setup-maven-action@v1.11.0
        with:
          maven-version: 3.8.7

      # Step 2b: Install ImageMagick (required for notification module)
      - name: Install ImageMagick
        run: |
          sudo apt-get update
          sudo apt-get install -y imagemagick
      # Step 3: Download the Maven repository from the first job
      # This contains all the built dependencies needed for jobs-distribution
      - name: Restore Maven local repository
        uses: actions/download-artifact@v4.3.0
        with:
          name: maven-repo
          path: ~/.m2/repository

      # Step 3a: Build all modules sequentially to ensure dependencies are available
      # Since parallel artifact sharing is complex, build all modules here
      - name: Build all modules for jobs-distribution
        run: |
          # Build notification module
          cd notification
          mvn clean install -DskipTests
          cd ..
          
          # Build lms-jobs module
          cd lms-jobs
          mvn clean install -DskipTests
          cd ..
          
          # Build user-org-jobs module
          cd user-org-jobs
          mvn clean install -DskipTests
          cd ..
          
          # Build ml-jobs module
          cd ml-jobs
          mvn clean install -DskipTests
          cd ..
      # Step 3b: Verify all artifacts are available
      - name: Verify Maven artifacts
        run: |
          echo "Checking Maven repository structure..."
          find ~/.m2/repository/org/sunbird -name "*.jar" -o -name "*.pom" | head -20
          echo "Total sunbird artifacts: $(find ~/.m2/repository/org/sunbird -name "*.jar" | wc -l)"
      # Step 4: Cache Maven packages (same as other jobs)
      # This ensures we have the same caching benefits in this job
      - name: Cache Maven packages
        uses: actions/cache@v3
        with:
          path: ~/.m2/repository
          key: ${{ runner.os }}-maven-${{ hashFiles('**/pom.xml') }}
          restore-keys: |
            ${{ runner.os }}-maven-
      # Step 5: Authenticate with Docker registry
      # Supports multiple registry providers: GCP, Azure, Docker Hub, or GitHub Container Registry
      - name: Login Docker Registry
        run: |        
          case "${{ vars.REGISTRY_PROVIDER }}" in
          "gcp")
            # Google Cloud Platform Container Registry
            echo "${{ secrets.GCP_SERVICE_ACCOUNT_KEY }}" | base64 --decode > $HOME/gcloud-key.json
            gcloud auth activate-service-account --key-file=$HOME/gcloud-key.json
            gcloud auth configure-docker ${{ secrets.REGISTRY_NAME }}
            REGISTRY_URL=$(echo "${{ secrets.REGISTRY_URL }}" | tr '[:upper:]' '[:lower:]') 
            ;;
          "azure" | "dockerhub")
            # Azure Container Registry or Docker Hub
            echo "${{ secrets.REGISTRY_PASSWORD }}" | docker login "${{ secrets.REGISTRY_NAME }}" \
            --username "${{ secrets.REGISTRY_USERNAME }}" --password-stdin
            REGISTRY_URL="$(echo "${{ secrets.REGISTRY_URL }}/$(basename "${{ github.workspace }}")" | tr '[:upper:]' '[:lower:]')"
            ;;
          *)
            # Default: GitHub Container Registry (ghcr.io)
            REPO_NAME_LOWERCASE=$(echo "${GITHUB_REPOSITORY}" | tr '[:upper:]' '[:lower:]')
            echo "${{ secrets.GITHUB_TOKEN }}" | docker login ghcr.io -u ${{ github.actor }} --password-stdin
            REGISTRY_URL="ghcr.io/$REPO_NAME_LOWERCASE"
            ;;
            esac
            echo "REGISTRY_URL=${REGISTRY_URL}" >> $GITHUB_ENV
      # Step 6: Build the jobs-distribution module
      # This module creates the final distribution package that gets included in the Docker image
      # It depends on all the modules built in the parallel jobs
      - name: Build jobs-distribution
        working-directory: jobs-distribution
        run: |
          # Package the distribution (creates jobs-distribution-1.0.tar.gz)
          # This contains all the job JARs and dependencies
          mvn package -DskipTests
      # Step 7: Build Docker image
      # Uses the Dockerfile in jobs-distribution directory
      # The image contains the Flink runtime and our job distribution
      - name: Build Docker Image
        working-directory: jobs-distribution
        run: |
          # Create image tag from git ref and commit SHA
          # Format: <tag-name>_<first-7-chars-of-sha>
          # Example: v1.0.0_a1b2c3d
          IMAGE_TAG=$(echo "${{ github.ref_name }}_$(echo $GITHUB_SHA | cut -c1-7)" | tr '[:upper:]' '[:lower:]')
          
          # Build the Docker image
          # The Dockerfile copies jobs-distribution-1.0.tar.gz and extracts it
          docker build -t ${REGISTRY_URL}:${IMAGE_TAG} .
          
          # Make the image tag available to subsequent steps
          echo "IMAGE_TAG=${IMAGE_TAG}" >> $GITHUB_ENV
     
      # Step 8: Push the Docker image to the registry
      - name: Push Docker Image
        run: |
          # Push the tagged image to the configured registry
          docker push ${REGISTRY_URL}:${IMAGE_TAG}
          echo "Successfully built and pushed Docker image: ${REGISTRY_URL}:${IMAGE_TAG}"