feat: github updater

.github/workflows/update.yaml

@@ -0,0 +1,52 @@
+# https://github.com/sandhose/nixconf/blob/master/.github/workflows/update.yaml
+name: "Update lock file"
+on:
+  schedule:
+    - cron: "0 */6 * * *"
+  workflow_dispatch:
+jobs:
+  tests:
+    runs-on: ubuntu-20.04
+
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          fetch-depth: 0
+
+      - uses: tibdex/github-app-token@v1.5
+        id: generate-token
+        with:
+          app_id: ${{ secrets.APP_ID }}
+          private_key: ${{ secrets.APP_PRIVATE_KEY }}
+
+      - uses: cachix/install-nix-action@v16
+        with:
+          install_url: https://releases.nixos.org/nix/nix-2.4/install
+          extra_nix_config: |
+            experimental-features = nix-command flakes
+            access-tokens = github.com=${{ secrets.GITHUB_TOKEN }}
+
+      - name: Setup Git author
+        run: |
+          git config user.name 'GitHub Ations'
+          git config user.email 'noreply@github.com'
+
+      - name: Update lock file
+        run: nix flake update --no-registries --commit-lock-file
+
+      - name: Get commit message
+        id: commit
+        run: |
+          message="$(git log -1 --pretty=%B | tail +3 | awk -f ./misc/flake-to-markdown.awk)"
+          message="${message//'%'/'%25'}"
+          message="${message//$'\n'/'%0A'}"
+          message="${message//$'\r'/'%0D'}"
+          echo "::set-output name=message::$message"
+
+      - name: Create Pull Request
+        uses: peter-evans/create-pull-request@v3.14.0
+        with:
+          token: "${{ steps.generate-token.outputs.token }}"
+          title: "Automated Flake update"
+          body: "${{ steps.commit.outputs.message }}"
+          delete-branch: truec