docs.yml

name: Docs

# Build the MkDocs Material site and deploy it to GitHub Pages.
#
# One-time setup required: in the repo, go to Settings → Pages and set
# "Source" to "GitHub Actions". After that, every push to main that touches the
# docs builds and publishes automatically.

on:
  push:
    branches: [main]
    paths:
      - docs/**
      - mkdocs.yml
      - requirements-docs.txt
      - .github/workflows/docs.yml
  pull_request:
    branches: [main]
    paths:
      - docs/**
      - mkdocs.yml
      - requirements-docs.txt
      - .github/workflows/docs.yml
  # Allow manual runs from the Actions tab.
  workflow_dispatch:

# Cancel superseded runs on the same PR/branch to save runner minutes.
concurrency:
  group: docs-${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true

jobs:
  build:
    name: Build site
    runs-on: ubuntu-latest
    permissions:
      contents: read
    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Set up Python
        uses: actions/setup-python@v5
        with:
          python-version: "3.x"
          cache: pip
          cache-dependency-path: requirements-docs.txt

      - name: Install dependencies
        run: pip install -r requirements-docs.txt

      # --strict turns warnings (broken nav links, missing images/refs) into
      # errors, so a bad doc fails the build instead of shipping silently.
      - name: Build site
        run: mkdocs build --strict

      - name: Upload Pages artifact
        # Only publish from main; PRs build-check only (see deploy job's `if`).
        uses: actions/upload-pages-artifact@v3
        with:
          path: site

  deploy:
    name: Deploy to GitHub Pages
    # Only deploy on pushes to main, never on PRs.
    if: github.ref == 'refs/heads/main' && github.event_name != 'pull_request'
    needs: build
    runs-on: ubuntu-latest
    permissions:
      pages: write
      id-token: write
    environment:
      name: github-pages
      url: ${{ steps.deployment.outputs.page_url }}
    steps:
      - name: Deploy to GitHub Pages
        id: deployment
        uses: actions/deploy-pages@v4