build.yml

name: Build website

on:
  # Build after every push to main
  push:
    branches:
      - main
  # Build on every PR
  pull_request:

jobs:

  # =================
  # Build the website
  # =================
  build:
    runs-on: ubuntu-latest

    steps:
      - name: Checkout repo
        uses: actions/checkout@v4

      - name: Setup Node
        uses: actions/setup-node@v4
        with:
          node-version: '20'

      - name: Install MyST
        run: |
          npm install -g mystmd

      - name: Print MyST version
        run: myst --version

      - name: Build website as static HTML
        run: |
          echo "Building MyST website using BASE_URL=" $BASE_URL
          myst build --html
        env:
          BASE_URL: /${{ github.event.repository.name }}

      # Store the website as a build artifact so we can deploy it later
      - name: Upload HTML website as an artifact
        # Only if not a pull request
        if: success() && github.event_name != 'pull_request'
        uses: actions/upload-artifact@v4
        with:
          name: html-${{ github.sha }}
          path: _build/html


  # ==================
  # Deploy the website
  # ==================
  deploy:
    runs-on: ubuntu-latest
    needs: build
    if: github.event_name != 'pull_request'

    steps:
      - name: Checkout repo
        uses: actions/checkout@v4

      # Fetch the built HTML from the build job
      - name: Download HTML artifact
        uses: actions/download-artifact@v4
        with:
          name: html-${{ github.sha }}
          path: _build/html

      - name: Deploy to gh-pages
        if: success() && github.event_name != 'pull_request'
        # Don't use tags: https://julienrenaux.fr/2019/12/20/github-actions-security-risk/
        uses: peaceiris/actions-gh-pages@4f9cc6602d3f66b9c108549d475ec49e8ef4d45e
        with:
          github_token: ${{ secrets.GITHUB_TOKEN }}
          publish_dir: _build/html
          publish_branch: gh-pages
          enable_jekyll: false
          force_orphan: true