pipeline.yml

name: CI/CD Pipeline

# Workflow triggers
on:
  push:
    branches: [ "main" ]
    paths-ignore: 
  pull_request: 
    branches: [ "main" ]
    paths-ignore:
  # Schedule pipeline to run monday midnight after sunday ends
  schedule:
    - cron: 0 0 * * MON
  # Enable manual runs of workflow
  workflow_dispatch:

# Workflow stages
jobs:      
  # Perform Lint Checks
  lint:
    name: Style and Lint Checks
    runs-on: ubuntu-latest
    defaults:
      run:
        working-directory: ./
    steps:
    - uses: actions/checkout@v3
    - name: Use Node.js 20.x
      uses: actions/setup-node@v3
      with:
        node-version: '20.x'
    - name: Install pnpm
      run: npm install -g pnpm
    - name: Install Dependencies
      run: pnpm install
    - name: Run lint script
      run: pnpm run lint

  # Run Unit Tests
  test:
    name: Unit Tests
    needs: lint
    runs-on: ubuntu-latest
    defaults:
      run:
        working-directory: ./
    steps:
    - uses: actions/checkout@v3
    - name: Use Node.js 20.x
      uses: actions/setup-node@v3
      with:
        node-version: 20.x
    - name: Install pnpm
      run: npm install -g pnpm
    - name: Install dependencies
      run: pnpm install
    - name: Run unit tests with jest
      run: pnpm run test

  # Build Application
  build:
    name: Build Application
    needs: test
    runs-on: ubuntu-latest
    defaults:
      run:
        working-directory: ./
    steps:
    - uses: actions/checkout@v3
    - name: Use Node.js 20.x
      uses: actions/setup-node@v3
      with:
        node-version: '20.x'
    - name: Install pnpm
      run: npm install -g pnpm
    - name: Install Dependencies
      run: pnpm install
    - name: Compile TypeScript into JavaScript
      run: pnpm run build

  # detect if there were code changes:
  detect-code-changes:
    name: Detect Code Changes
    needs: build
    runs-on: ubuntu-latest
    outputs:
      code_changes: ${{ steps.files.outputs.code_changes }}
    steps:
      - uses: actions/checkout@v3
      - name: Determine Changed Files
        id: files
        run: |
          echo "CODE_CHANGES=true" >> $GITHUB_ENV
          if git diff --name-only ${{ github.base_ref }}...${{ github.head_ref }} | grep -qvE '(\.md$|\.github/workflows/)'
          then
            echo "CODE_CHANGES=true" >> $GITHUB_ENV
          else
            echo "CODE_CHANGES=false" >> $GITHUB_ENV
          fi

  # Verify new NPM version is updated during push and PR. 
  # Skips version number check step if there were code changes
  verify-npm-version:
    name: Verify Updated NPM version
    if: github.event_name == 'push' || github.event_name == 'pull_request' # run version checks only on PR and push
    needs: detect-code-changes
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v3
        with:
          fetch-depth: 0 # Fetches all history for all branches and tags
      - name: Use Node.js
        uses: actions/setup-node@v3
        with:
          node-version: '20.x'
          registry-url: 'https://registry.npmjs.org/'
      - name: Install dependencies
        run: npm install
      - name: Check if version number is updated
        if: env.CODE_CHANGES == 'true' # only run verification if there were code changes
        id: check_version
        run: |
          LATEST_TAG=$(git describe --tags --abbrev=0)
          PACKAGE_VERSION=$(node -p "require('./package.json').version")
          if [ "$LATEST_TAG" = "v$PACKAGE_VERSION" ]; then
            echo "Version in package.json is already published. Exiting..."
            exit 1
          fi

  # publish to NPM if:
  #   - It was a push
  #   - There were code changes
  publish-npm:
    name: Publish to NPM
    if: github.event_name == 'push' && env.CODE_CHANGES == 'true'
    needs: verify-npm-version
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v3
        with:
          fetch-depth: 0 # Fetches all history for all branches and tags
      - name: Use Node.js
        uses: actions/setup-node@v3
        with:
          node-version: '20.x'
          registry-url: 'https://registry.npmjs.org/'
      - name: Install dependencies
        run: npm install
      - name: Check if version updated
        id: check_version
        run: |
          LATEST_TAG=$(git describe --tags --abbrev=0)
          PACKAGE_VERSION=$(node -p "require('./package.json').version")
          echo "::set-output name=version::$PACKAGE_VERSION"
      - name: Publish to NPM
        if: steps.check_version.outputs.version
        run: npm publish
        env:
          NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}

  # Create Release on GitHub if:
  #   - It was a push
  #   - There were code changes
  release:
    name: Create Release
    if: github.event_name == 'push' && env.CODE_CHANGES == 'true'
    needs: verify-npm-version
    runs-on: ubuntu-latest
    steps:
      - name: Checkout code
        uses: actions/checkout@v3
      - name: Extract version number
        id: package_version
        run: echo "::set-output name=VERSION::$(jq -r .version package.json)"
      - name: Create Release
        uses: actions/create-release@v1
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        with:
          tag_name: ${{ steps.package_version.outputs.VERSION }}
          release_name: Release ${{ steps.package_version.outputs.VERSION }}
          draft: false
          prerelease: false