flakes-update.yml

name: Automated Nix flakes-managed dependency updates
on:
  schedule:
    # * is a special character in YAML so you have to quote this string
    # run this every day at 4:00am
    - cron:  '0 4 * * *'
jobs:
  nix-flakes-updater:
    name: 'Create PRs for Nix flakes-managed dependencies'
    runs-on: ubuntu-latest
    # Borrowed from https://github.com/Mic92/dotfiles/blob/9c2fc2cc98021dd8d42bbb714278785a9a6757c2/.github/workflows/upgrade-flakes.yml
    steps:
      - uses: actions/checkout@v2
      - uses: cachix/install-nix-action@v14
        with:
          install_url: https://github.com/numtide/nix-flakes-installer/releases/download/nix-2.4pre20210415_76980a1/install
          extra_nix_config: |
            experimental-features = nix-command flakes
      - name: Make changes to pull request
        run: nix flake update
      - name: Create Pull Request
        id: cpr
        uses: peter-evans/create-pull-request@v3
        with:
          commit-message: Update flakes
          committer: GitHub <noreply@github.com>
          author: ${{ github.actor }} <${{ github.actor }}@users.noreply.github.com>
          signoff: false
          branch: flake-updates
          delete-branch: true
          title: 'Upgrade flakes'
          body: |
            Update report
            - Updated with *today's* date
            - Auto-generated by [create-pull-request][1]
            [1]: https://github.com/peter-evans/create-pull-request
      - name: Check outputs
        run: |
          echo "Pull Request Number - ${{ steps.cpr.outputs.pull-request-number }}"
          echo "Pull Request URL - ${{ steps.cpr.outputs.pull-request-url }}"