synapse/.github/workflows/docs.yaml

name: Deploy the documentation

on:
  push:
    branches:
      # For bleeding-edge documentation
      - develop
      # For documentation specific to a release
      - 'release-v*'
      # stable docs
      - master

  workflow_dispatch:

jobs:
  pages:
    name: GitHub Pages
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2

      - name: Setup mdbook
        uses: peaceiris/actions-mdbook@4b5ef36b314c2599664ca107bb8c02412548d79d # v1.1.14
        with:
          mdbook-version: '0.4.17'

      - name: Build the documentation
        # mdbook will only create an index.html if we're including docs/README.md in SUMMARY.md.
        # However, we're using docs/README.md for other purposes and need to pick a new page
        # as the default. Let's opt for the welcome page instead.
        run: |
          mdbook build
          cp book/welcome_and_overview.html book/index.html

      # Figure out the target directory.
      #
      # The target directory depends on the name of the branch
      #
      - name: Get the target directory name
        id: vars
        run: |
          # first strip the 'refs/heads/' prefix with some shell foo
          branch="${GITHUB_REF#refs/heads/}"

          case $branch in
              release-*)
                  # strip 'release-' from the name for release branches.
                  branch="${branch#release-}"
                  ;;
              master)
                  # deploy to "latest" for the master branch.
                  branch="latest"
                  ;;
          esac

          # finally, set the 'branch-version' var.
          echo "::set-output name=branch-version::$branch"
          
      # Deploy to the target directory.
      - name: Deploy to gh pages
        uses: peaceiris/actions-gh-pages@068dc23d9710f1ba62e86896f84735d869951305 # v3.8.0
        with:
          github_token: ${{ secrets.GITHUB_TOKEN }}
          publish_dir: ./book
          destination_dir: ./${{ steps.vars.outputs.branch-version }}