Generate default LL server config and attach it to GH release (#6430)

.github/workflows/publish_release.yml

@@ -80,10 +80,38 @@ jobs:
           name: build-output
           path: ./dist
 
+  generate_default_ll_server_config:
+    name: Generate default application.yml
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Set up Python
+        uses: actions/setup-python@v4
+        with:
+          python-version: '3.8'
+
+      - name: Install script's dependencies
+        run: python -m pip install PyYAML
+
+      - name: Generate default application.yml
+        env:
+          APP_YML_FILE: "Red-DiscordBot-${{ github.ref_name }}-default-lavalink-application.yml"
+        run: |
+          mkdir -p dist
+          python .github/workflows/scripts/get_default_ll_server_config.py "dist/$APP_YML_FILE"
+
+      - name: Upload default application.yml
+        uses: actions/upload-artifact@v3
+        with:
+          name: ll-default-server-config
+          path: ./dist
+
   release_to_pypi:
     needs:
       - release_information
       - build
+      - generate_default_ll_server_config
     environment: Release
     name: Release to PyPI
     runs-on: ubuntu-latest
@@ -96,6 +124,18 @@ jobs:
           name: build-output
           path: dist/
 
+      - name: Download default application.yml
+        uses: actions/download-artifact@v3
+        with:
+          name: ll-default-server-config
+          path: dist/
+
+      - name: Upload dists to GitHub Release
+        env:
+          GITHUB_TOKEN: "${{ github.token }}"
+        run: |
+          gh release upload "$GITHUB_REF_NAME" dist/*
+
       - name: Publish package distributions to PyPI
         uses: pypa/gh-action-pypi-publish@release/v1
         with:

.github/workflows/scripts/get_default_ll_server_config.py

@@ -0,0 +1,31 @@
+import sys
+from pathlib import Path
+
+import yaml
+
+ROOT_FOLDER = Path(__file__).parents[3].absolute()
+AUDIO_FOLDER = ROOT_FOLDER / "redbot/cogs/audio"
+
+# We want to import `redbot.cogs.audio.managed_node` package as if it were top-level package
+# so we have to the `redbot/cogs/audio` directory to Python's path.
+sys.path.insert(0, str(AUDIO_FOLDER))
+
+
+def main() -> int:
+    try:
+        output_file = sys.argv[1]
+    except IndexError:
+        print("Usage:", sys.argv[0], "<output_file>", file=sys.stderr)
+        return 2
+
+    import managed_node
+
+    server_config = managed_node.get_default_server_config()
+    with open(output_file, "w", encoding="utf-8") as fp:
+        yaml.safe_dump(server_config, fp)
+
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())