From 3e5749b99fc47a28681178d96923519866b3ae5d Mon Sep 17 00:00:00 2001 From: Andrew Morgan <1342360+anoadragon453@users.noreply.github.com> Date: Wed, 17 Feb 2021 17:31:37 +0000 Subject: [PATCH] Fix only handling the last presence state for each user (#9425) This is a small bug that I noticed while working on #8956. We have a for-loop which attempts to strip all presence changes for each user except for the final one, as we don't really care about older presence: https://github.com/matrix-org/synapse/blob/9e19c6aab4b5a99039f2ddc7d3120dd3b26c274b/synapse/handlers/presence.py#L368-L371 `new_states_dict` stores this stripped copy of latest presence state for each user, before it is... put into a new variable `new_state`, which is just overridden by the subsequent for loop. I believe this was instead meant to override `new_states`. Without doing so, it effectively meant: 1. The for loop had no effect. 2. We were still processing old presence state for users. --- changelog.d/9425.bugfix | 1 + synapse/handlers/presence.py | 7 +++++-- 2 files changed, 6 insertions(+), 2 deletions(-) create mode 100644 changelog.d/9425.bugfix diff --git a/changelog.d/9425.bugfix b/changelog.d/9425.bugfix new file mode 100644 index 000000000..f5b8857cd --- /dev/null +++ b/changelog.d/9425.bugfix @@ -0,0 +1 @@ +Fix a long-standing bug in the deduplication of old presence, resulting in no deduplication. \ No newline at end of file diff --git a/synapse/handlers/presence.py b/synapse/handlers/presence.py index 7ba22d511..ed90b5d45 100644 --- a/synapse/handlers/presence.py +++ b/synapse/handlers/presence.py @@ -349,10 +349,13 @@ class PresenceHandler(BasePresenceHandler): [self.user_to_current_state[user_id] for user_id in unpersisted] ) - async def _update_states(self, new_states): + async def _update_states(self, new_states: Iterable[UserPresenceState]) -> None: """Updates presence of users. Sets the appropriate timeouts. Pokes the notifier and federation if and only if the changed presence state should be sent to clients/servers. + + Args: + new_states: The new user presence state updates to process. """ now = self.clock.time_msec() @@ -368,7 +371,7 @@ class PresenceHandler(BasePresenceHandler): new_states_dict = {} for new_state in new_states: new_states_dict[new_state.user_id] = new_state - new_state = new_states_dict.values() + new_states = new_states_dict.values() for new_state in new_states: user_id = new_state.user_id