Firebase hosting with preview channels for pull requests

deploy_hosting.yml

name: Hosting
on:
  pull_request:
    branches:
      - development
      - staging
      - main
  push:
    branches:
      - development
      - staging
      - main

env:
  IS_PR_DEV: ${{github.event_name == 'pull_request' && github.base_ref == 'development'}}
  IS_PUSH_DEV: ${{github.event_name == 'push' && github.ref == 'refs/heads/development'}}

  IS_PR_STAGING: ${{github.event_name == 'pull_request' && github.base_ref == 'staging'}}
  IS_PUSH_STAGING: ${{github.event_name == 'push' && github.ref == 'refs/heads/staging'}}

  IS_PR_PROD: ${{github.event_name == 'pull_request' && github.base_ref == 'main'}}
  IS_PUSH_PROD: ${{github.event_name == 'push' && github.ref == 'refs/heads/main'}}

jobs:
  deploy:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v3

      - uses: actions/setup-node@v3
        with:
          node-version: 16
          cache: 'yarn'
          cache-dependency-path: |
            web-app/yarn.lock
            
      - name: Install YARN packages
        run: yarn --cwd web-app install

      - name: Linting files
        run: yarn --cwd web-app lint --no-fix

      - name: Set development environment variables
        if: env.IS_PR_DEV == 'true' || env.IS_PUSH_DEV == 'true'
        run: |
          echo "PROJECT_ALIAS=${{secrets.DEVELOPMENT_PROJECT_ALIAS}}" >> $GITHUB_ENV
          echo "SA_FIREBASE=${{secrets.DEVELOPMENT_SA}}" >> $GITHUB_ENV

      - name: Set staging environment variables
        if: env.IS_PUSH_STAGING == 'true'
        run: |
          echo "PROJECT_ALIAS=${{secrets.STAGING_PROJECT_ALIAS}}" >> $GITHUB_ENV
          echo "SA_FIREBASE=${{secrets.STAGING_SA}}" >> $GITHUB_ENV

      - name: Set production environment variables
        if: env.IS_PUSH_PROD == 'true'
        run: |
          echo "PROJECT_ALIAS=${{secrets.PRODUCTION_PROJECT_ALIAS}}" >> $GITHUB_ENV
          echo "SA_FIREBASE=${{secrets.PRODUCTION_SA}}" >> $GITHUB_ENV

      # The variable `SA_FIREBASE` must be a base64 encoded string
      # of the service account JSON to avoid problems with quote escaping and
      # conversion of '\n' characters generating invalid JSON
      - name: Set service account for Firebase CLI
        run: |
          echo "GOOGLE_APPLICATION_CREDENTIALS=$(pwd)/service_account.json" >> $GITHUB_ENV
          echo ${{ env.SA_FIREBASE }} | base64 -d - > service_account.json
          
      - run: firebase use ${{ env.PROJECT_ALIAS }}

      - run: yarn --cwd web-app build

      - name: Deploy preview channel to Firebase
        if: github.event_name == 'pull_request'
        # Deploying to preview channel using the branch name as channel name
        # String split '/' and use the last part of the branch name
        run: >-
            firebase
            hosting:channel:deploy
            $(echo ${{ github.head_ref }} | grep -o '[^/]*$')
            --expires 5d

      - name: Deploy to Firebase
        if: github.event_name == 'push'
        run: >-
            firebase deploy
            --only hosting
            -m "Github action run $GITHUB_RUN_ID"
            --non-interactive
            --force