deploy_pr_preview.yml

name: "Rebuild and deploy PR version of book to gh-pages branch in pull###/ folder"
on:
  pull_request:
    types: [opened, synchronize]
    paths:
      - 'source/**'
      - 'Dockerfile'
    branches:
      - 'main'
jobs:
  deploy-pr-preview:
    runs-on: ubuntu-latest
    permissions:
      contents: write
      packages: write
      pull-requests: write

    steps:
      - name: Wait for potential build environment update
        uses: fountainhead/action-wait-for-check@v1.1.0
        with:
          token: ${{ secrets.GITHUB_TOKEN }}
          checkName: "Rebuild docker image"
          ref: ${{ github.event.pull_request.head.sha }}
          timeoutSeconds: 60000
          
      - name: Get Actions user id
        id: get_uid
        run: |
          actions_user_id=`id -u $USER`
          echo $actions_user_id
          echo "uid=$actions_user_id" >> $GITHUB_OUTPUT
          
      - name: Checkout the repo
        uses: actions/checkout@v2
        with:
          fetch-depth: '0'
          ref: ${{ github.head_ref }}
          
      - name: Build the book
        run: |
          ./build_html.sh

      - name: Reset ownership of workspace after build
        uses: peter-murray/reset-workspace-ownership-action@v1
        with:
          user_id: ${{ steps.get_uid.outputs.uid }}

       # Push the book's HTML to github-pages
      - name: GitHub Pages action
        uses: peaceiris/actions-gh-pages@v3.8.0
        with:
          github_token: ${{ secrets.GITHUB_TOKEN }}
          publish_dir: source/_build/html
          keep_files: true
          destination_dir: pull${{ github.event.number }}
          # force_orphan: true # once peaceiris updates to v4, change this to true and keep_files: true for the PR / main branch deploy previews

      - name: Checkout the gh-pages branch
        uses: actions/checkout@v2
        with:
          fetch-depth: '0'
          ref: 'gh-pages'

      - name: Run website diff
        run: |
          rustup update
          pip install --upgrade pip
          pip install website_diff
          rm -rf diff${{ github.event.number }}
          website_diff --old dev --new pull${{ github.event.number }} --diff diff${{ github.event.number }}

      - name: GitHub Pages action to push diff
        uses: peaceiris/actions-gh-pages@v3.8.0
        with:
          github_token: ${{ secrets.GITHUB_TOKEN }}
          publish_dir: diff${{ github.event.number }}
          keep_files: true
          destination_dir: diff${{ github.event.number }}
          # force_orphan: true # once peaceiris updates to v4, change this to true and keep_files: true for the PR / main branch deploy previews

      - name: Post URLS to PR thread
        uses: mshick/add-pr-comment@v2.8.1
        with:
          message: |
              Hello! I've built a preview of your PR so that you can compare it to the current `main` branch.
              * PR deploy preview available [here](https://python.datasciencebook.ca/pull${{ github.event.number }}/index.html)
              * PR diff with `main` available [here](https://python.datasciencebook.ca/diff${{ github.event.number }}/index.html)
              * Current `main` deploy preview available [here](https://python.datasciencebook.ca/dev/index.html)
              * Public production build available [here](https://python.datasciencebook.ca)