GitHub Actions

这一课你将能做到

1. 编写 GitHub Actions 工作流
2. 实现 CI（自动测试、构建）
3. 实现 CD（自动部署到服务器）

为什么要学

手动部署容易出错：忘测试、环境不一致、版本混乱。GitHub Actions 在代码提交后自动执行测试、构建、部署，保证每次发布质量一致。

人话：GitHub Actions 是「机器人」，代码一提交就自动帮你测试、打包、上线。

跟着做

步骤 1：基础工作流

# .github/workflows/ci.yml
name: CI

on:
  push:
    branches: [main]
  pull_request:
    branches: [main]

jobs:
  test:
    runs-on: ubuntu-latest

    steps:
      - name: Checkout code
        uses: actions/checkout@v3

      - name: Setup Node.js
        uses: actions/setup-node@v3
        with:
          node-version: '18'
          cache: 'npm'

      - name: Install dependencies
        run: npm ci

      - name: Run tests
        run: npm test

      - name: Build
        run: npm run build

步骤 2：矩阵测试（多版本）

jobs:
  test:
    runs-on: ubuntu-latest
    strategy:
      matrix:
        node-version: [16, 18, 20]

    steps:
      - uses: actions/checkout@v3

      - name: Setup Node.js ${{ matrix.node-version }}
        uses: actions/setup-node@v3
        with:
          node-version: ${{ matrix.node-version }}

      - run: npm ci
      - run: npm test

步骤 3：自动部署

name: Deploy

on:
  push:
    branches: [main]

jobs:
  deploy:
    runs-on: ubuntu-latest
    needs: test  # 等 test 通过

    steps:
      - uses: actions/checkout@v3

      - name: Deploy to server
        uses: appleboy/ssh-action@master
        with:
          host: ${{ secrets.SERVER_HOST }}
          username: ${{ secrets.SERVER_USER }}
          key: ${{ secrets.SSH_KEY }}
          script: |
            cd /var/www/app
            git pull origin main
            npm install --production
            npm run build
            pm2 restart app

步骤 4：缓存加速

steps:
  - uses: actions/checkout@v3

  - name: Cache node_modules
    uses: actions/cache@v3
    with:
      path: ~/.npm
      key: ${{ runner.os }}-node-${{ hashFiles('**/package-lock.json') }}
      restore-keys: |
        ${{ runner.os }}-node-

  - run: npm ci

步骤 5：环境变量与 Secrets

env:
  NODE_ENV: production

jobs:
  deploy:
    steps:
      - run: echo "${{ secrets.API_KEY }}"