[Template] Github action build multi-arch docker images

build.yaml

name: Build multi-arch docker images

on:
  push:
    branches:
      - "master"

    tags:
      - "v*.*.*"

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      # Change IMAGE="username/repo" to match your project
      # Three kinds of image tags will be generated:
      # master, latest, v*.*.*
      - name: Prepare
        id: prep
        run: |
          TAGS="" 
          IMAGE="username/repo"  

          if [[ "$GITHUB_REF" == refs/heads/master ]]; then
            TAGS="$IMAGE:master"
          elif [[ "$GITHUB_REF" == refs/tags/* ]]; then
            VERSION="${GITHUB_REF#refs/tags/}"
            TAGS="$IMAGE:$VERSION,$IMAGE:latest"
          fi

          echo "📚 building ref: $GITHUB_REF"
          echo "🏷 image tags: $TAGS"
          echo ::set-output name=tags::${TAGS}


      - name: Checkout 
        uses: actions/checkout@v2
        
      - name: Setup QEMU
        uses: docker/setup-qemu-action@v1

      - name: Setup Docker buildx
        uses: docker/setup-buildx-action@v1
        with:
          version: latest
          driver-opts: image=moby/buildkit:master

      - name: Cache Docker layers
        uses: actions/cache@v2
        with:
          path: /tmp/.buildx-cache
          key: ${{ runner.os }}-buildx-${{ github.sha }}
          restore-keys: |
            ${{ runner.os }}-buildx-    

      - name: Login Docker hub
        uses: docker/login-action@v1
        # Remember to add DOCKER_USERNAME, DOCKER_TOKEN to your project secrets
        with:
          username: ${{ secrets.DOCKER_USERNAME }}
          password: ${{ secrets.DOCKER_TOKEN }}

      - name: Build and push
        uses: docker/build-push-action@v2
        # Change parameters to match your project
        with:
          context: .  # here
          file: /path/to/Dockerfile  # here
          platforms: linux/amd64,linux/arm64,linux/armv7
          push: true  # here
          tags: ${{ steps.prep.outputs.tags }} # here
          cache-from: type=local,src=/tmp/.buildx-cache
          cache-to: type=local,dest=/tmp/.buildx-cache