ci-github-actions

When to Use

Apply when setting up CI/CD pipelines: automated testing, linting, building, and deployment with GitHub Actions.

Patterns

Pattern 1: Basic CI Workflow

# Source: https://docs.github.com/en/actions/quickstart
# .github/workflows/ci.yml
name: CI

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

jobs:
  test:
    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v5

      - name: Setup Node.js
        uses: actions/setup-node@v6
        with:
          node-version: '22'
          cache: 'npm'

      - name: Install dependencies
        run: npm ci

      - name: Run linter
        run: npm run lint

      - name: Run tests
        run: npm test

      - name: Build
        run: npm run build

Pattern 2: Matrix Testing

# Source: https://docs.github.com/en/actions/using-jobs/using-a-matrix-for-your-jobs
jobs:
  test:
    runs-on: ubuntu-latest
    strategy:
      matrix:
        node-version: [20, 22, 24]
        os: [ubuntu-latest, windows-latest]

    steps:
      - uses: actions/checkout@v5
      - uses: actions/setup-node@v6
        with:
          node-version: ${{ matrix.node-version }}
      - run: npm ci
      - run: npm test

Pattern 3: Caching Dependencies

# Source: https://docs.github.com/en/actions/using-workflows/caching-dependencies-to-speed-up-workflows
- name: Cache node modules
  uses: actions/cache@v4
  with:
    path: ~/.npm
    key: ${{ runner.os }}-node-${{ hashFiles('**/package-lock.json') }}
    restore-keys: |
      ${{ runner.os }}-node-

# Or use setup-node cache option
- uses: actions/setup-node@v6
  with:
    node-version: '22'
    cache: 'npm'  # Automatic caching

Pattern 4: Environment Secrets

# Source: https://docs.github.com/en/actions/security-guides/encrypted-secrets
jobs:
  deploy:
    runs-on: ubuntu-latest
    environment: production  # Use environment-specific secrets

    steps:
      - name: Deploy
        env:
          DATABASE_URL: ${{ secrets.DATABASE_URL }}
          API_KEY: ${{ secrets.API_KEY }}
        run: |
          npm run deploy

Pattern 5: Conditional Jobs

# Source: https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions
jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - run: npm test

  deploy:
    needs: test  # Run after test passes
    if: github.ref == 'refs/heads/main'  # Only on main
    runs-on: ubuntu-latest
    steps:
      - run: npm run deploy

  notify:
    needs: [test, deploy]
    if: failure()  # Only if previous jobs failed
    runs-on: ubuntu-latest
    steps:
      - run: echo "Build failed!"

Pattern 6: Reusable Workflows

# Source: https://docs.github.com/en/actions/using-workflows/reusing-workflows
# .github/workflows/reusable-test.yml
name: Reusable Test

on:
  workflow_call:
    inputs:
      node-version:
        required: false
        type: string
        default: '22'

jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v5
      - uses: actions/setup-node@v6
        with:
          node-version: ${{ inputs.node-version }}
      - run: npm ci && npm test

# Usage in another workflow
jobs:
  call-tests:
    uses: ./.github/workflows/reusable-test.yml
    with:
      node-version: '22'

Anti-Patterns

• No caching - Always cache dependencies
• Secrets in logs - Never echo secrets
• Long monolithic workflows - Split into jobs
• No branch protection - Require CI pass for merge

Verification Checklist

• CI runs on PRs and main pushes
• Dependencies cached
• Secrets stored in GitHub Secrets
• Tests must pass before merge
• Build artifacts preserved if needed