Build ARM Images in GitHub Actions

build-docker-image.yml

name: Build Docker Image

on:
  workflow_dispatch:
  push: { branches: [ 'implement-docker' ] }

env:
  REGISTRY: ghcr.io
  IMAGE_USER: your_username
  IMAGE_NAME: your_username/project_name

jobs:
  docker:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@v3
      - name: Login to GHCR
        uses: docker/login-action@v2
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ env.IMAGE_USER }}
          password: ${{ secrets.GH_TOKEN }}
      - name: Set up QEMU
        uses: docker/setup-qemu-action@v2
      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v2
      - name: Get Composer Cache Directory
        id: composer-cache
        run: |
          echo "dir=$(composer config cache-files-dir)" >> $GITHUB_OUTPUT
      - name: Cache Docker layers
        uses: actions/cache@v3
        with:
          path: |
            /tmp/.buildx-cache
            ${{ steps.composer-cache.outputs.dir }}
          key: ${{ runner.os }}-buildx-${{ github.sha }}
          restore-keys: |
            ${{ runner.os }}-buildx-
      - name: Extract metadata
        id: meta
        uses: docker/metadata-action@v4
        with:
          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
          flavor: |
            latest=true
          tags: |
            type=schedule,pattern={{date 'YYYYMMDD-HHmmss' tz='UTC'}}
            type=ref,event=branch
            type=ref,event=pr
            type=semver,pattern={{major}}.{{minor}}.{{patch}}
            type=semver,pattern={{version}}
            type=semver,pattern={{major}}
            type=sha
      - name: Build and push
        uses: docker/build-push-action@v4
        with:
          context: .
          push: true
          tags: ${{ steps.meta.outputs.tags }}
          platforms: linux/amd64,linux/arm64
          file: ./docker/prod/Dockerfile
          cache-from: |
            type=local,src=/tmp/.buildx-cache
            type=local,src=${{ steps.composer-cache.outputs.dir }}
          cache-to: |
            type=local,dest=/tmp/.buildx-cache
            type=local,dest=${{ steps.composer-cache.outputs.dir }}

Dockerfile

# more stages...

# When using a Node image, make sure to use the amd64 version, or it will take forever
# GH Actions is running arm64 in a emulator (QEMU). This way, it will use the native amd64 and be much faster.
FROM --platform=linux/amd64 node:19 as static-assets
WORKDIR /app
COPY . .
RUN npm install ; npm run build

# more stages...

prune-registry.yml

name: Prune Registry

on:
  workflow_dispatch:
  schedule:
    - cron: 0 0 * * *


env:
  # For image ghcr.io/foo/bar, it will use 'foo' because of the token, and 'bar' is the project_name
  # For more options for configs, see https://github.com/vlaurin/action-ghcr-prune
  PROJECT_NAME: project_name

jobs:
  prune-images:
    runs-on: ubuntu-latest
    steps:
      - name: Prune
        uses: vlaurin/action-ghcr-prune@v0.5.0
        with:
          token: ${{ secrets.GH_TOKEN }}
          container: ${{ env.PROJECT_NAME }}
          dry-run: true # Dry-run first, then change to `false`
          keep-younger-than: 0 # days
          keep-last: 6
          prune-untagged: true