From 43237a42589ffce605b8aa9e1a3a423aa832e744 Mon Sep 17 00:00:00 2001
From: Carlton Gibson <carlton.gibson@noumenal.es>
Date: Fri, 5 Aug 2022 15:49:31 +0200
Subject: [PATCH] Made daphne installable as a Django app.

Added system check to ensure daphne is installed before
django.contrib.staticfiles.
---
 daphne/apps.py   | 20 ++++++++++++++++++++
 daphne/checks.py | 20 ++++++++++++++++++++
 2 files changed, 40 insertions(+)
 create mode 100644 daphne/apps.py
 create mode 100644 daphne/checks.py

diff --git a/daphne/apps.py b/daphne/apps.py
new file mode 100644
index 0000000..3dd62fa
--- /dev/null
+++ b/daphne/apps.py
@@ -0,0 +1,20 @@
+# Import the server here to ensure the reactor is installed very early on in case other
+# packages import twisted.internet.reactor (e.g. raven does this).
+import daphne.server  # noqa: F401
+
+
+try:
+    # Allow that Django is not installed.
+    from django.apps import AppConfig
+    from django.core import checks
+    from .checks import check_daphne_installed
+except ImportError:
+    pass
+else:
+
+    class DaphneConfig(AppConfig):
+        name = "daphne"
+        verbose_name = "Daphne"
+
+        def ready(self):
+            checks.register(check_daphne_installed, checks.Tags.staticfiles)
diff --git a/daphne/checks.py b/daphne/checks.py
new file mode 100644
index 0000000..ba67d12
--- /dev/null
+++ b/daphne/checks.py
@@ -0,0 +1,20 @@
+# Django system check to ensure daphne app is listed in INSTALLED_APPS before django.contrib.staticfiles.
+from django.core.checks import Error, register
+
+
+@register()
+def check_daphne_installed(app_configs, **kwargs):
+    from daphne.apps import DaphneConfig
+    from django.apps import apps
+    from django.contrib.staticfiles.apps import StaticFilesConfig
+
+    for app in apps.get_app_configs():
+        if isinstance(app, DaphneConfig):
+            return []
+        if isinstance(app, StaticFilesConfig):
+            return [
+                Error(
+                    "Daphne must be listed before django.contrib.staticfiles in INSTALLED_APPS.",
+                    id="daphne.E001",
+                )
+            ]