Fix a race between started/stopped stream

This commit is contained in:
Mark Haines 2015-12-14 15:09:41 +00:00
parent 8505a4ddc3
commit dbe7892e03

View file

@ -69,7 +69,12 @@ class EventStreamHandler(BaseHandler):
A deferred that completes once their presence has been updated.
"""
if user not in self._streams_per_user:
self._streams_per_user[user] = 0
# Make sure we set the streams per user to 1 here rather than
# setting it to zero and incrementing the value below.
# Otherwise this may race with stopped_stream causing the
# user to be erased from the map before we have a chance
# to increment it.
self._streams_per_user[user] = 1
if user in self._stop_timer_per_user:
try:
self.clock.cancel_call_later(
@ -79,7 +84,7 @@ class EventStreamHandler(BaseHandler):
logger.exception("Failed to cancel event timer")
else:
yield started_user_eventstream(self.distributor, user)
else:
self._streams_per_user[user] += 1
def stopped_stream(self, user):