react-navigation/.github/workflows/expo-preview.yml

name: Expo Preview
on: [pull_request]

jobs:
  publish:
    name: Install and publish
    runs-on: ubuntu-latest
    if: github.event.pull_request.head.repo.owner.login == 'react-navigation'
    steps:
      - name: Checkout
        uses: actions/checkout@v2

      - name: Setup Node.js
        uses: actions/setup-node@v1
        with:
          node-version: 10.x

      - name: Setup Expo
        uses: expo/expo-github-action@v5
        with:
          expo-version: 3.x
          expo-username: ${{ secrets.EXPO_CLI_USERNAME }}
          expo-password: ${{ secrets.EXPO_CLI_PASSWORD }}
          expo-cache: true

      - name: Restore yarn cache
        id: yarn-cache
        uses: actions/cache@v2
        with:
          path: '**/node_modules'
          key: ${{ runner.os }}-yarn-${{ hashFiles('**/yarn.lock') }}

      - name: Install dependencies
        if: steps.yarn-cache.outputs.cache-hit != 'true'
        run: yarn install --frozen-lockfile

      - name: Publish Expo app
        working-directory: ./example
        run: expo publish --release-channel=pr-${{ github.event.number }}
        env:
          EXPO_USE_DEV_SERVER: true

      - name: Get expo link
        id: expo
        run: echo "::set-output name=path::@react-navigation/react-navigation-example?release-channel=pr-${{ github.event.number }}"

      - name: Comment on PR
        uses: actions/github-script@v3
        with:
          github-token: ${{secrets.GITHUB_TOKEN}}
          script: |
            const body = 'The Expo app for the example from this branch is ready!\n\n[expo.io/${{ steps.expo.outputs.path }}](https://expo.io/${{ steps.expo.outputs.path }})\n\n<a href="https://exp.host/${{ steps.expo.outputs.path }}"><img src="https://api.qrserver.com/v1/create-qr-code/?size=400x400&data=exp://exp.host/${{ steps.expo.outputs.path }}" height="200px" width="200px"></a>';

            const comments = await github.issues.listComments({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
            });

            if (comments.data.some(comment => comment.body === body)) {
              return;
            }

            github.issues.createComment({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              body
            })