From dde7110c0dd91752b5891d217408e4513d2c2a31 Mon Sep 17 00:00:00 2001
From: Erik Johnston <erik@matrix.org>
Date: Thu, 29 Nov 2018 11:49:38 +0000
Subject: [PATCH] Reduce transaction response size

---
 synapse/federation/federation_server.py | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/synapse/federation/federation_server.py b/synapse/federation/federation_server.py
index 1d25b7c479..5d4dc6370c 100644
--- a/synapse/federation/federation_server.py
+++ b/synapse/federation/federation_server.py
@@ -672,7 +672,10 @@ class FederationServer(FederationBase):
             span=span,
         )
 
-        defer.returnValue({"did_not_relay": list(dont_relay)})
+        ret = {}
+        if dont_relay:
+            ret = {"did_not_relay": list(dont_relay)}
+        defer.returnValue(ret)
 
     def __str__(self):
         return "<ReplicationLayer(%s)>" % self.server_name