From 4db3331bb95a655bb56ab8333be49ee183f71715 Mon Sep 17 00:00:00 2001
From: Erik Johnston <erik@matrix.org>
Date: Mon, 16 Jan 2023 14:20:12 +0000
Subject: [PATCH] Add an early return when handling no-op presence updates.
(#14855)
This stops us from incrementing the presence stream position for no-op updates.
---
changelog.d/14855.misc | 1 +
synapse/handlers/presence.py | 5 +++++
2 files changed, 6 insertions(+)
create mode 100644 changelog.d/14855.misc
diff --git a/changelog.d/14855.misc b/changelog.d/14855.misc
new file mode 100644
index 0000000000..f0e292f287
--- /dev/null
+++ b/changelog.d/14855.misc
@@ -0,0 +1 @@
+Add an early return when handling no-op presence updates.
diff --git a/synapse/handlers/presence.py b/synapse/handlers/presence.py
index 2af90b25a3..43e4e7b1b4 100644
--- a/synapse/handlers/presence.py
+++ b/synapse/handlers/presence.py
@@ -2155,6 +2155,11 @@ class PresenceFederationQueue:
# This should only be called on a presence writer.
assert self._presence_writer
+ if not states or not destinations:
+ # Ignore calls which either don't have any new states or don't need
+ # to be sent anywhere.
+ return
+
if self._federation:
self._federation.send_presence_to_destinations(
states=states,