如何在Azure DevOps流水线中构建linux/arm64/v8架构Docker镜像

我有一个Azure DevOps构建流水线，生成的是amd64架构的Docker镜像，在树莓派4上运行时失败，报错提示需要linux/arm64/v8架构的镜像。该镜像用于构建C# .NET6控制台应用，原流水线YAML配置如下：

trigger:
  branches:
    include:
    - master
  paths:
    include:
    - 'XXXXX/*'

variables:
  tag: '$(Build.BuildId)'
  dockerrepo: 'xxxxxxx'

stages:
- stage: Build
  displayName: Build image
  jobs:
  - job: Build
    displayName: Build
    pool:
      vmImage: ubuntu-latest
    steps:
    - task: Docker@2
      inputs:
        containerRegistry: 'xxxxx Container Registry'
        repository: $(dockerrepo)
        command: 'buildAndPush'
        Dockerfile: '*/Dockerfile'
        tags: |
          $(tag)

我尝试添加platform参数并拆分build和push任务，但构建时出现无效参数错误，修改后的YAML配置如下：

stages:
- stage: Build
  displayName: Build image
  jobs:
  - job: Build
    displayName: Build
    pool:
      vmImage: ubuntu-latest
    steps:
    - task: Docker@2
      inputs:
        containerRegistry: 'xxxxxxx Container Registry'
        repository: $(dockerrepo)
        command: build
        arguments: '--platform linux/arm64/v8'
        Dockerfile: '*/Dockerfile'
        tags: |
          $(tag)
    - task: Docker@2
      inputs:
        containerRegistry: 'xxxxxxx Container Registry'
        repository: $(dockerrepo)
        command: push
        Dockerfile: '*/Dockerfile'
        tags: |
          $(tag)

请问如何调整流水线，使其构建出适配树莓派4的指定架构镜像？

1. 修正Docker@2任务的架构配置方式 #

你之前的错误在于直接在arguments中添加--platform参数，这会和Docker@2任务的内部逻辑冲突。该任务提供了专门的dockerBuildPlatform参数来指定构建架构，无需手动在arguments中传递。

2. 完整的流水线YAML配置（两种可选方式） #

方式一：使用buildAndPush一键构建推送

保留原有的buildAndPush命令，添加dockerBuildPlatform参数指定架构：

trigger:
  branches:
    include:
    - master
  paths:
    include:
    - 'XXXXX/*'

variables:
  tag: '$(Build.BuildId)'
  dockerrepo: 'xxxxxxx'

stages:
- stage: Build
  displayName: Build image
  jobs:
  - job: Build
    displayName: Build
    pool:
      vmImage: ubuntu-latest
    steps:
    - task: Docker@2
      inputs:
        containerRegistry: 'xxxxx Container Registry'
        repository: $(dockerrepo)
        command: 'buildAndPush'
        Dockerfile: '*/Dockerfile'
        tags: |
          $(tag)
        dockerBuildPlatform: 'linux/arm64/v8'

方式二：拆分build和push任务

如果需要拆分步骤，同样使用dockerBuildPlatform参数而不是arguments：

trigger:
  branches:
    include:
    - master
  paths:
    include:
    - 'XXXXX/*'

variables:
  tag: '$(Build.BuildId)'
  dockerrepo: 'xxxxxxx'

stages:
- stage: Build
  displayName: Build image
  jobs:
  - job: Build
    displayName: Build
    pool:
      vmImage: ubuntu-latest
    steps:
    - task: Docker@2
      inputs:
        containerRegistry: 'xxxxxxx Container Registry'
        repository: $(dockerrepo)
        command: build
        dockerBuildPlatform: 'linux/arm64/v8'
        Dockerfile: '*/Dockerfile'
        tags: |
          $(tag)
    - task: Docker@2
      inputs:
        containerRegistry: 'xxxxxxx Container Registry'
        repository: $(dockerrepo)
        command: push
        tags: |
          $(tag)

3. 确保Dockerfile适配arm64架构 #

.NET6官方基础镜像（如mcr.microsoft.com/dotnet/sdk:6.0-bookworm-slim、mcr.microsoft.com/dotnet/runtime:6.0-bookworm-slim）均支持多架构，无需修改。如果使用了自定义基础镜像，需确保其为linux/arm64/v8架构。

示例适配的.NET6控制台应用Dockerfile：

FROM mcr.microsoft.com/dotnet/sdk:6.0-bookworm-slim AS build
WORKDIR /src
COPY ["YourApp.csproj", "."]
RUN dotnet restore "./YourApp.csproj"
COPY . .
WORKDIR "/src/."
RUN dotnet build "YourApp.csproj" -c Release -o /app/build

FROM build AS publish
RUN dotnet publish "YourApp.csproj" -c Release -o /app/publish /p:UseAppHost=false

FROM mcr.microsoft.com/dotnet/runtime:6.0-bookworm-slim AS final
WORKDIR /app
COPY --from=publish /app/publish .
ENTRYPOINT ["dotnet", "YourApp.dll"]

内容的提问来源于stack exchange，提问作者mark_h