Merge pull request #175 from DakaraProject/fix/174-daphne

Fix websocket management for Daphne

Author: Neraste

dakara_server/dakara_server/asgi.py

@@ -10,14 +10,18 @@
 from channels.security.websocket import AllowedHostsOriginValidator
 from django.core.asgi import get_asgi_application
 
-from dakara_server.routing import websocket_urlpatterns
-from dakara_server.token_auth import TokenAuthMiddleware
-
 os.environ.setdefault("DJANGO_SETTINGS_MODULE", "dakara_server.settings.development")
 
+# Initialize Django ASGI application early to ensure the AppRegistry is
+# populated before importing code that may import ORM models.
+asgi_application = get_asgi_application()
+
+from dakara_server.routing import websocket_urlpatterns  # noqa E402
+from dakara_server.token_auth import TokenAuthMiddleware  # noqa E402
+
 application = ProtocolTypeRouter(
     {
-        "http": get_asgi_application(),
+        "http": asgi_application,
         "websocket": AllowedHostsOriginValidator(
             AuthMiddlewareStack(TokenAuthMiddleware(URLRouter(websocket_urlpatterns)))
         ),

dakara_server/dakara_server/settings/base.py

@@ -28,6 +28,7 @@
     "django.contrib.contenttypes",
     "django.contrib.sessions",
     "django.contrib.messages",
+    "daphne",
     "django.contrib.staticfiles",
     "rest_framework",
     "rest_framework.authtoken",

dakara_server/playlist/signals.py

@@ -1,20 +1,28 @@
+from threading import Event
+
 from django.db.backends.signals import connection_created
 from django.dispatch import receiver
 
 from internal.reloader import is_reloader
 
+connection_created_once = Event()
+
 
 @receiver(connection_created)
 def handle_connection_created(connection, **kwargs):
     """Perform playlist initialization operations as soon as the database is
     ready."""
-    from playlist.date_stop import check_date_stop_on_app_ready
-    from playlist.models import clean_channel_names
+    # make sure this code is called only once
+    if not connection_created_once.is_set():
+        connection_created_once.set()
+
+        from playlist.date_stop import check_date_stop_on_app_ready
+        from playlist.models import clean_channel_names
 
-    clean_channel_names()
+        clean_channel_names()
 
-    if is_reloader():
-        return
+        if is_reloader():
+            return
 
-    # not called by the reloader
-    check_date_stop_on_app_ready()
+        # not called by the reloader
+        check_date_stop_on_app_ready()