docker-image.yaml

name: Docker Image CI

on:
  push:
    branches: [ "main" ]
  pull_request:
    branches: [ "main" ]

env:
  # Use docker.io for Docker Hub if empty
  REGISTRY: ghcr.io
  # github.repository as <account>/<repo>
  IMAGE_NAME: ${{ github.repository }}

jobs:

  build:
    runs-on: ubuntu-latest

    permissions:
      packages: write

    steps:
    - name: Checkout repository
      uses: actions/checkout@v4

    # Set up BuildKit Docker container builder to be able to build
    # multi-platform images and export cache
    # https://github.com/docker/setup-buildx-action
    - name: Set up Docker Buildx
      uses: docker/setup-buildx-action@v3

    # Login against a Docker registry except on PR
    # https://github.com/docker/login-action
    - name: Log into registry ${{ env.REGISTRY }}
      if: github.event_name != 'pull_request'
      uses: docker/login-action@v3
      with:
        registry: ${{ env.REGISTRY }}
        username: ${{ github.actor }}
        password: ${{ secrets.GITHUB_TOKEN }}

    # Extract metadata (tags, labels) for Docker
    # https://github.com/docker/metadata-action
    - name: Extract Docker metadata
      id: meta
      uses: docker/metadata-action@v5
      with:
        images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
        tags: |
          type=schedule
          type=semver,pattern={{version}}
          type=semver,pattern={{major}}.{{minor}}
          type=semver,pattern={{major}}
          type=ref,event=branch
          type=ref,event=pr
          type=sha
          type=raw,value=latest,enable=${{ github.ref == format('refs/heads/{0}', 'main') }}

    # Build and push Docker image with Buildx (don't push on PR)
    # https://github.com/docker/build-push-action
    - name: Build and push Docker image
      id: build-and-push
      uses: docker/build-push-action@v6
      with:
        context: .
        platforms: linux/arm64,linux/amd64
        push: ${{ github.event_name != 'pull_request' }}
        tags: ${{ steps.meta.outputs.tags }}
        labels: ${{ steps.meta.outputs.labels }}
        cache-from: type=gha
        cache-to: type=gha,mode=max