name: Docker build and publish

# 参见: https://docs.docker.com/build/ci/github-actions/multi-platform/

on:
  push:
    branches: [ "beta" ]
    # Publish semver tags as releases.
    tags: [ 'v*.*.*' ]
  pull_request:
    branches: [ "master" ]

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

jobs:
  build:
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
        platform:
          - linux/i386
          - linux/amd64
          - linux/arm/v6
          - linux/arm/v7
          - linux/arm64

    permissions:
      contents: read
      packages: write
      # This is used to complete the identity challenge
      # with sigstore/fulcio when running outside of PRs.
      id-token: write

    steps:
      - name: Prepare
        run: |
          platform=${{ matrix.platform }}
          echo "PLATFORM_PAIR=${platform//\//-}" >> $GITHUB_ENV   

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

      # Install the cosign tool except on PR
      # https://github.com/sigstore/cosign-installer
      - name: Install cosign
        if: github.event_name != 'pull_request'
        uses: sigstore/cosign-installer@6e04d228eb30da1757ee4e1dd75a0ec73a653e06 #v3.1.1
        with:
          cosign-release: 'v2.1.1'

      - name: Docker meta
        id: meta
        uses: docker/metadata-action@v5
        with:
          images: ${{ env.IMAGE_NAME }}

      - name: Set up QEMU
        uses: docker/setup-qemu-action@v3

      # 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.DOCKER_HUB_TOKEN }}

      # 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
        uses: docker/build-push-action@v5
        with:
          context: .
          platforms: ${{ matrix.platform }}
          push: ${{ github.event_name != 'pull_request' }}
          labels: ${{ steps.meta.outputs.labels }}
          outputs: type=image,name=${{ env.IMAGE_NAME }},push-by-digest=true,name-canonical=true,push=true

      - name: Export digest
        run: |
          mkdir -p /tmp/digests
          digest="${{ steps.build.outputs.digest }}"
          touch "/tmp/digests/${digest#sha256:}"          

      - name: Upload digest
        uses: actions/upload-artifact@v4
        with:
          name: digests-${{ env.PLATFORM_PAIR }}
          path: /tmp/digests/*
          if-no-files-found: error
          retention-days: 1

  merge:
    runs-on: ubuntu-latest
    needs:
      - build
    steps:
      - name: Download digests
        uses: actions/download-artifact@v4
        with:
          path: /tmp/digests
          pattern: digests-*
          merge-multiple: true

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3

      - name: Docker meta
        id: meta
        uses: docker/metadata-action@v5
        with:
          images: ${{ env.IMAGE_NAME }}

      - name: Login to Docker Hub
        uses: docker/login-action@v3
        with:
          username: ${{ github.actor }}
          password: ${{ secrets.DOCKER_HUB_TOKEN }}

      - name: Create manifest list and push
        working-directory: /tmp/digests
        run: |
          docker buildx imagetools create $(jq -cr '.tags | map("-t " + .) | join(" ")' <<< "$DOCKER_METADATA_OUTPUT_JSON") \
            $(printf '${{ env.IMAGE_NAME }}@sha256:%s ' *)          

      - name: Inspect image
        run: |
          docker buildx imagetools inspect ${{ env.IMAGE_NAME }}:${{ steps.meta.outputs.version }}