diff --git a/daphne/cli.py b/daphne/cli.py
index 7579938..0becb7b 100755
--- a/daphne/cli.py
+++ b/daphne/cli.py
@@ -22,6 +22,8 @@ class ASGI3Middleware:
         self.app = app
 
     def __call__(self, scope):
+        scope.setdefault("asgi", {})
+        scope["asgi"]["version"] = "3.0"
         return functools.partial(self.asgi, scope=scope)
 
     async def asgi(self, receive, send, scope):