如何用通用GitHub Action YAML文件实现路径独立触发构建？

问题场景 #

我有3个GitHub Action工作流YAML文件，核心构建逻辑完全一致，仅触发条件不同——分别在代码推送到path1/**、path2/**等不同路径时，构建对应名称的Docker镜像。示例文件如下：

# yml1
name: build docker image 1 
on:
  push:
    paths:
      - "path1/**"
jobs:
  build-docker-image:
    runs-on: ubuntu-latest
    # 此处为核心构建逻辑（如镜像构建、推送等）

# yml2
name: build docker image 2
on:
  push:
    paths:
      - "path2/**"
jobs:
  build-docker-image:
    runs-on: ubuntu-latest
    # 此处为核心构建逻辑（如镜像构建、推送等）

需求：

• 保留各路径独立的触发规则，仅对应路径有代码推送时才触发构建；
• 将多个工作流合并为单个YAML文件，复用核心构建代码，避免重复维护。

解决方案 #

方案1：矩阵策略+路径条件判断（推荐，高复用率） #

通过定义路径与镜像的映射矩阵，结合GitHub Actions内置的条件判断，实现单文件监听所有目标路径，且仅在对应路径变更时执行镜像构建。

name: Build Docker Images by Path
on:
  push:
    # 监听所有目标路径的推送事件
    paths:
      - "path1/**"
      - "path2/**"
      - "path3/**" # 按需添加更多路径

jobs:
  build-docker-image:
    runs-on: ubuntu-latest
    strategy:
      matrix:
        # 定义路径与镜像名称的一一映射关系
        target:
          - path: "path1/**"
            image-name: "image-1"
          - path: "path2/**"
            image-name: "image-2"
          - path: "path3/**"
            image-name: "image-3" # 按需扩展更多映射项
    # 仅当当前矩阵项对应的路径有变更时，才执行该任务
    if: contains(github.event.head_commit.modified, matrix.target.path)
    steps:
      - name: Checkout code
        uses: actions/checkout@v4

      # 复用核心构建逻辑，通过矩阵变量动态指定镜像名和路径
      - name: Build & Push Docker Image
        run: |
          # 进入目标路径构建镜像
          cd ./${{ matrix.target.path }}
          docker build -t ${{ matrix.target.image-name }} .
          # 此处添加镜像推送等后续步骤（如docker push）

方案2：变更检测+独立任务（高灵活性） #

先通过单独任务检测各路径是否有变更，再根据检测结果触发对应镜像的构建任务，适合需要为不同镜像添加差异化构建步骤的场景。

name: Build Docker Images by Path
on:
  push:
    paths:
      - "path1/**"
      - "path2/**"
      - "path3/**"

jobs:
  # 第一步：检测各路径是否有代码变更
  detect-path-changes:
    runs-on: ubuntu-latest
    outputs:
      path1-changed: ${{ steps.diff-check.outputs.path1 }}
      path2-changed: ${{ steps.diff-check.outputs.path2 }}
      path3-changed: ${{ steps.diff-check.outputs.path3 }}
    steps:
      - name: Checkout code
        uses: actions/checkout@v4
        with:
          fetch-depth: 2 # 拉取上一提交用于对比

      - name: Check path changes
        id: diff-check
        run: |
          # 对比当前提交与上一提交，标记各路径是否变更
          git diff --name-only HEAD^ HEAD | grep -q "path1/" && echo "path1=true" >> $GITHUB_OUTPUT || echo "path1=false" >> $GITHUB_OUTPUT
          git diff --name-only HEAD^ HEAD | grep -q "path2/" && echo "path2=true" >> $GITHUB_OUTPUT || echo "path2=false" >> $GITHUB_OUTPUT
          git diff --name-only HEAD^ HEAD | grep -q "path3/" && echo "path3=true" >> $GITHUB_OUTPUT || echo "path3=false" >> $GITHUB_OUTPUT

  # 第二步：根据变更结果构建对应镜像
  build-image-1:
    runs-on: ubuntu-latest
    needs: detect-path-changes
    if: needs.detect-path-changes.outputs.path1-changed == 'true'
    steps:
      - name: Checkout code
        uses: actions/checkout@v4
      # 复用核心构建逻辑，构建image-1
      - name: Build Image 1
        run: |
          docker build -t image-1 ./path1
          # 添加镜像推送等步骤

  build-image-2:
    runs-on: ubuntu-latest
    needs: detect-path-changes
    if: needs.detect-path-changes.outputs.path2-changed == 'true'
    steps:
      - name: Checkout code
        uses: actions/checkout@v4
      # 复用核心构建逻辑，构建image-2
      - name: Build Image 2
        run: |
          docker build -t image-2 ./path2
          # 添加镜像推送等步骤

  # 按需添加build-image-3等任务

内容的提问来源于stack exchange，提问作者DarkMatter