build.yaml

name: Build and deploy

on:
  push:
  pull_request:

permissions:
  contents: read
  pages: write
  id-token: write

jobs:
  build:
    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v2
      - uses: DeterminateSystems/nix-installer-action@main
      - uses: DeterminateSystems/magic-nix-cache-action@main

      - name: Update npm dep hash
        run: |
          # Only recompute the hash if the lock changed
          git diff --quiet --cached package-lock.json \
            || nix run .#compute-npm-dep-hash

      - name: Commit and push npm-dep-hash
        run: |
          git config --local user.email "action@github.com"
          git config --local user.name "GitHub Action"
          git add .
          # Only commit if the dep hash changed
          git diff --quiet --cached npm-deps-hash \
            || git commit -m "Update npm dep hash [skip ci]"
          git push

      - name: Build project
        run: nix build .#doffycup-github-pages

      - name: Upload artifact
        uses: actions/upload-pages-artifact@v2
        with:
          path: ./result/www

  deploy:
    environment:
      name: github-pages
      url: ${{ steps.deployment.outputs.page_url }}

    runs-on: ubuntu-latest
    needs: build
    if: github.event_name == 'push' && github.ref == 'refs/heads/main'

    steps:
      - name: Deploy to GitHub Pages
        id: deployment
        uses: actions/deploy-pages@v2