check-pr-docs-build.yml

name: Docs Build (PR)
# The documentation is built and deployed in the nightly-docs.yml workflow.
# This workflow builds the documentation for pull requests to the main branch
# to catch any issues building the documentation before merging.


on:
  pull_request:
    branches:
      - main


concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true


jobs:
  docs_build:
    name: Build docs
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@v4

      - name: Load Visor env
        uses: ./.github/actions/load-visor-env

      # Install Xvfb and Mesa for headless OpenGL rendering (needed for VTK and similar libraries)
      - name: Install Xvfb and Mesa
        run: |
          sudo apt-get update
          sudo apt-get install -y xvfb mesa-utils libgl1

      # Start Xvfb on display :99 to provide a virtual X server for graphical tests
      - name: Start Xvfb
        run: |
          Xvfb :99 -screen 0 1920x1080x24 &
          echo "DISPLAY=:99" >> $GITHUB_ENV

      # Run tests with DISPLAY=:99 (for Xvfb) and VTK_DEFAULT_RENDER_WINDOW_OFFSCREEN=1
      # VTK_DEFAULT_RENDER_WINDOW_OFFSCREEN=1 ensures VTK uses offscreen rendering to avoid X errors
      - name: Run Ansys documentation building action
        uses: ansys/actions/doc-build@v11.1.3
        env:
          DISPLAY: ":99"  # Use the virtual X server started by Xvfb
          VTK_DEFAULT_RENDER_WINDOW_OFFSCREEN: "1"  # Force VTK to use offscreen rendering
        with:
          checkout: false
          python-version: ${{ env.MAIN_PYTHON_VERSION }}
          check-links: false
          sphinxopts: '-j auto'
          optional-dependencies-name: ""
          group-dependencies-name: "doc"