1 files changed, 7 insertions, 2 deletions
diff --git a/synapse/http/server.py b/synapse/http/server.py
index 996a31a9ec..00b98af3d4 100644
--- a/synapse/http/server.py
+++ b/synapse/http/server.py
@@ -257,7 +257,7 @@ class _AsyncResource(resource.Resource, metaclass=abc.ABCMeta):
             if isinstance(raw_callback_return, (defer.Deferred, types.CoroutineType)):
                 callback_return = await raw_callback_return
             else:
-                callback_return = raw_callback_return
+                callback_return = raw_callback_return  # type: ignore
 
             return callback_return
 
@@ -406,7 +406,7 @@ class JsonResource(DirectServeJsonResource):
         if isinstance(raw_callback_return, (defer.Deferred, types.CoroutineType)):
             callback_return = await raw_callback_return
         else:
-            callback_return = raw_callback_return
+            callback_return = raw_callback_return  # type: ignore
 
         return callback_return
 
@@ -651,6 +651,11 @@ def respond_with_json_bytes(
     Returns:
         twisted.web.server.NOT_DONE_YET if the request is still active.
     """
+    if request._disconnected:
+        logger.warning(
+            "Not sending response to request %s, already disconnected.", request
+        )
+        return
 
     request.setResponseCode(code)
     request.setHeader(b"Content-Type", b"application/json")