docs workflow (xarray-contrib/xarray-spatial)

name: docs
on:
  pull_request:
    paths:
      - 'docs/**'
      - 'README.md'
      - 'setup.cfg'
      - '.readthedocs.yml'
      - '.github/workflows/docs.yml'
  workflow_dispatch:
  schedule:
    # Weekly linkcheck (Monday 06:00 UTC). External links rot on their
    # own schedule, not the PR schedule; checking them per-PR cost ~10
    # minutes of runner time and its failures were masked by
    # continue-on-error anyway.
    - cron: '0 6 * * 1'
 
concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true
 
jobs:
  # Job id/name kept distinct from the pytest workflow's `run` job:
  # duplicate check names across workflows get deduplicated in the PR
  # checks UI and can hide failures.
  docs-build:
    if: github.event_name != 'schedule'
    runs-on: latchkey-small
    # Normal runs take ~4 minutes (install ~1, HTML build ~3 with
    # parallel read), so 15 leaves headroom without letting a wedged
    # run camp on a runner.
    timeout-minutes: 15
    steps:
    - uses: actions/checkout@v4
    - name: Setup Python
      uses: actions/setup-python@v5
      with:
        cache: 'pip'
        # Match the Read the Docs build (.readthedocs.yml).
        python-version: '3.12'
    - name: Install pandoc
      # nbsphinx needs the pandoc binary; the `pandoc` pip package in
      # the doc extra does not ship it.
      run: sudo apt-get update && sudo apt-get install -y pandoc
    - name: Install dependencies
      # Same extras as the Read the Docs pre_build step, so this job
      # and RTD cannot drift apart.
      run: |
        python -m pip install --upgrade pip
        pip install -e '.[doc,tests]'
    - name: Build HTML
      # No -W: the build carries a handful of pre-existing warnings in
      # notebooks and reference pages. Gate on errors only.
      #
      # -j auto: the read phase is dominated by plot-directive examples
      # in the reference docstrings (sample data load + numba compile
      # per page, 30-60s each); all extensions in conf.py declare
      # parallel_read_safe, so this fans them out across the runner's
      # cores.
      run: sphinx-build -b html -j auto docs/source docs/build/html
 
  # Linkcheck runs on the weekly schedule (or manual dispatch), not on
  # PRs: it took ~10 minutes per PR and never gated anything. Here it
  # is allowed to fail loudly so broken links actually surface.
  linkcheck:
    if: github.event_name != 'pull_request'
    runs-on: latchkey-small
    timeout-minutes: 30
    steps:
    - uses: actions/checkout@v4
    - name: Setup Python
      uses: actions/setup-python@v5
      with:
        cache: 'pip'
        python-version: '3.12'
    - name: Install pandoc
      run: sudo apt-get update && sudo apt-get install -y pandoc
    - name: Install dependencies
      run: |
        python -m pip install --upgrade pip
        pip install -e '.[doc,tests]'
    - name: Link check
      run: sphinx-build -b linkcheck docs/source docs/build/linkcheck