A Simple Analogy

GitHub Actions are like a helpful robot. Every time code changes, the robot automatically runs tests, builds, and deploys.

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Why GitHub Actions?

• Native: Built into GitHub
• Free: Unlimited runs for public repos
• Flexible: Run any code
• Secrets: Secure credential management
• Matrices: Test multiple configurations

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Basic Workflow

name: CI

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

jobs:
  test:
    runs-on: ubuntu-latest
    steps:
    - uses: actions/checkout@v3
    - name: Setup Node
      uses: actions/setup-node@v3
      with:
        node-version: '18'
    - name: Install dependencies
      run: npm ci
    - name: Run tests
      run: npm test
    - name: Upload coverage
      uses: codecov/codecov-action@v3

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Deployment Workflow

name: Deploy

on:
  push:
    branches: [ main ]

jobs:
  deploy:
    runs-on: ubuntu-latest
    steps:
    - uses: actions/checkout@v3
    - name: Deploy to production
      run: |
        echo "Deploying to Azure..."
        az appservice deployment source config-zip \
          --resource-group mygroup \
          --name myapp \
          --src-path ./app.zip
      env:
        AZURE_CREDENTIALS: ${{ secrets.AZURE_CREDENTIALS }}

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Matrix Testing

jobs:
  test:
    runs-on: ubuntu-latest
    strategy:
      matrix:
        node-version: [16.x, 18.x, 20.x]
        os: [ubuntu-latest, windows-latest]
    steps:
    - uses: actions/checkout@v3
    - uses: actions/setup-node@v3
      with:
        node-version: ${{ matrix.node-version }}
    - run: npm test

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Secrets & Variables

jobs:
  deploy:
    runs-on: ubuntu-latest
    steps:
    - name: Deploy
      run: npm run deploy
      env:
        DATABASE_URL: ${{ secrets.DATABASE_URL }}
        API_KEY: ${{ secrets.API_KEY }}
        ENVIRONMENT: ${{ vars.DEPLOYMENT_ENV }}

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Best Practices

1. Cache dependencies: Speed up runs
2. Fail fast: Run quick checks first
3. Concurrency: Use matrix for speed
4. Status checks: Required before merge
5. Notifications: Alert on failures

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Related Concepts

• Azure Pipelines
• GitLab CI
• Jenkins
• CircleCI

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Summary

Use GitHub Actions to automate testing, building, and deployment. Leverage workflow files for CI/CD pipelines.