使用 GitHub Actions 的多平台映像檔

目錄

您可以使用 platforms 選項建置 多平台映像檔，如下列範例所示

**注意**

建置和載入多平台映像檔

GitHub Actions 執行器的預設 Docker 設定不支援在建置多平台映像檔後將其載入到執行器的本機映像檔存放區。若要載入多平台映像檔，您需要為 Docker Engine 啟用 containerd 映像檔存放區選項。

無法直接在 GitHub Actions 執行器中設定預設 Docker 設定，但您可以使用 crazy-max/ghaction-setup-docker 工作流程來自訂作業的 Docker Engine 和 CLI 設定。

下列範例工作流程會啟用 containerd 映像檔存放區、建置多平台映像檔，並將結果載入 GitHub 執行器的本機映像檔存放區。

name: ci

on:
  push:

jobs:
  docker:
    runs-on: ubuntu-latest
    steps:
      - name: Set up Docker
        uses: crazy-max/ghaction-setup-docker@v3
        with:
          daemon-config: |
            {
              "debug": true,
              "features": {
                "containerd-snapshotter": true
              }
            }            

      - name: Login to Docker Hub
        uses: docker/login-action@v3
        with:
          username: ${{ vars.DOCKERHUB_USERNAME }}
          password: ${{ secrets.DOCKERHUB_TOKEN }}

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

      - name: Build and push
        uses: docker/build-push-action@v6
        with:
          platforms: linux/amd64,linux/arm64
          load: true
          tags: user/app:latest

將建置分散到多個執行器

在先前的範例中，每個平台都建置在同一個執行器上，這可能需要很長時間，取決於平台數量和您的 Dockerfile。

若要解決此問題，您可以使用矩陣策略將每個平台的建置分散到多個執行器，並使用 buildx imagetools create 命令 建立資訊清單。

下列工作流程將使用矩陣策略在專用執行器上建置每個平台的映像檔，並依摘要推送。然後，merge 作業將建立資訊清單並將其推送至 Docker Hub。

此範例也使用 metadata 工作流程

name: ci

on:
  push:

env:
  REGISTRY_IMAGE: user/app

jobs:
  build:
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
        platform:
          - linux/amd64
          - linux/arm/v6
          - linux/arm/v7
          - linux/arm64
    steps:
      - name: Prepare
        run: |
          platform=${{ matrix.platform }}
          echo "PLATFORM_PAIR=${platform//\//-}" >> $GITHUB_ENV          

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

      - name: Login to Docker Hub
        uses: docker/login-action@v3
        with:
          username: ${{ vars.DOCKERHUB_USERNAME }}
          password: ${{ secrets.DOCKERHUB_TOKEN }}

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

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

      - name: Build and push by digest
        id: build
        uses: docker/build-push-action@v6
        with:
          platforms: ${{ matrix.platform }}
          labels: ${{ steps.meta.outputs.labels }}
          outputs: type=image,name=${{ env.REGISTRY_IMAGE }},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: Login to Docker Hub
        uses: docker/login-action@v3
        with:
          username: ${{ vars.DOCKERHUB_USERNAME }}
          password: ${{ secrets.DOCKERHUB_TOKEN }}

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

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

      - 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.REGISTRY_IMAGE }}@sha256:%s ' *)          

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

使用 Bake

也可以使用 Bake 在多個執行器上建置，搭配 bake 工作流程此 GitHub 儲存庫上一節 中描述的相同。

variable "DEFAULT_TAG" {
  default = "app:local"
}

// Special target: https://github.com/docker/metadata-action#bake-definition
target "docker-metadata-action" {
  tags = ["${DEFAULT_TAG}"]
}

// Default target if none specified
group "default" {
  targets = ["image-local"]
}

target "image" {
  inherits = ["docker-metadata-action"]
}

target "image-local" {
  inherits = ["image"]
  output = ["type=docker"]
}

target "image-all" {
  inherits = ["image"]
  platforms = [
    "linux/amd64",
    "linux/arm/v6",
    "linux/arm/v7",
    "linux/arm64"
  ]
}
name: ci

on:
  push:

env:
  REGISTRY_IMAGE: user/app

jobs:
  prepare:
    runs-on: ubuntu-latest
    outputs:
      matrix: ${{ steps.platforms.outputs.matrix }}
    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Create matrix
        id: platforms
        run: |
          echo "matrix=$(docker buildx bake image-all --print | jq -cr '.target."image-all".platforms')" >>${GITHUB_OUTPUT}          

      - name: Show matrix
        run: |
          echo ${{ steps.platforms.outputs.matrix }}          

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

      - name: Rename meta bake definition file
        run: |
          mv "${{ steps.meta.outputs.bake-file }}" "/tmp/bake-meta.json"          

      - name: Upload meta bake definition
        uses: actions/upload-artifact@v4
        with:
          name: bake-meta
          path: /tmp/bake-meta.json
          if-no-files-found: error
          retention-days: 1

  build:
    runs-on: ubuntu-latest
    needs:
      - prepare
    strategy:
      fail-fast: false
      matrix:
        platform: ${{ fromJson(needs.prepare.outputs.matrix) }}
    steps:
      - name: Prepare
        run: |
          platform=${{ matrix.platform }}
          echo "PLATFORM_PAIR=${platform//\//-}" >> $GITHUB_ENV          

      - name: Checkout
        uses: actions/checkout@v4

      - name: Download meta bake definition
        uses: actions/download-artifact@v4
        with:
          name: bake-meta
          path: /tmp
      
      - name: Login to Docker Hub
        uses: docker/login-action@v3
        with:
          username: ${{ vars.DOCKERHUB_USERNAME }}
          password: ${{ secrets.DOCKERHUB_TOKEN }}

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

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

      - name: Build
        id: bake
        uses: docker/bake-action@v5
        with:
          files: |
            ./docker-bake.hcl
            /tmp/bake-meta.json            
          targets: image
          set: |
            *.tags=
            *.platform=${{ matrix.platform }}
            *.output=type=image,"name=${{ env.REGISTRY_IMAGE }}",push-by-digest=true,name-canonical=true,push=true            

      - name: Export digest
        run: |
          mkdir -p /tmp/digests
          digest="${{ fromJSON(steps.bake.outputs.metadata).image['containerimage.digest'] }}"
          touch "/tmp/digests/${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 meta bake definition
        uses: actions/download-artifact@v4
        with:
          name: bake-meta
          path: /tmp

      - name: Download digests
        uses: actions/download-artifact@v4
        with:
          path: /tmp/digests
          pattern: digests-*
          merge-multiple: true

      - name: Login to DockerHub
        uses: docker/login-action@v3
        with:
          username: ${{ vars.DOCKERHUB_USERNAME }}
          password: ${{ secrets.DOCKERHUB_TOKEN }}

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

      - name: Create manifest list and push
        working-directory: /tmp/digests
        run: |
          docker buildx imagetools create $(jq -cr '.target."docker-metadata-action".tags | map(select(startswith("${{ env.REGISTRY_IMAGE }}")) | "-t " + .) | join(" ")' /tmp/bake-meta.json) \
            $(printf '${{ env.REGISTRY_IMAGE }}@sha256:%s ' *)          

      - name: Inspect image
        run: |
          docker buildx imagetools inspect ${{ env.REGISTRY_IMAGE }}:$(jq -r '.target."docker-metadata-action".args.DOCKER_META_VERSION' /tmp/bake-meta.json)