base_image_build.yml

# This YAML file is used to build and push a base Docker image with the necessary tools and dependencies for an ML project
# It contains a job that builds the Docker image and pushes it to GitHub Container Registry

name: Base Docker Image - Build and Push 

on:
  # Trigger the workflow manually
  workflow_dispatch:

jobs:
  build_and_push:
    permissions:
      contents: read
      packages: write
  
    strategy:
      fail-fast: false
      matrix:
        include:
          - arch: amd64
            runner: ubuntu-latest
          - arch: arm64
            runner: ubuntu-24.04-arm
    runs-on: ${{ matrix.runner }}

    steps:
      - name: Checkout repository
        # Check out the repository containing the Dockerfile and other necessary files
        uses: actions/checkout@v6

      - name: Log in to GitHub Container Registry
        # Log in to GitHub Container Registry using the actor and a GitHub token
        uses: docker/login-action@v4
        with:
          registry: ghcr.io
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Set up Docker Buildx
        # Set up Docker Buildx for building multi-architecture images
        uses: docker/setup-buildx-action@v4

      - name: Format repo slug
        # Format the repository slug to lowercase for use in the Docker image tags
        id: repo_slug
        run: echo "REPO_SLUG=$(echo ${{ github.repository }} | tr '[:upper:]' '[:lower:]')" >> $GITHUB_ENV

      - name: Build and push Docker image
        # Build the Docker image using the Dockerfile in the `docker_base` directory and push it to GitHub Container Registry
        uses: docker/build-push-action@v7
        with:
          context: ./docker_base
          push: true
          tags: ghcr.io/${{ env.REPO_SLUG }}/arm-mlops-docker-base:latest-${{ matrix.arch }}
          # Use GitHub Actions cache to speed up the build process
          cache-from: type=gha,scope=${{ matrix.arch }}
          cache-to: type=gha,mode=max,scope=${{ matrix.arch }}