Mitigate against incorrect old state in /sync.

There have been reports from the field that servers occasionally have
incorrect notions of what the old state of a room is. This proves
problematic as /sync relies on a correct old state.
This patch makes /sync specifically include in the 'state' key any
current state events that haven't been correctly included.
This commit is contained in:
Erik Johnston 2016-02-12 11:13:06 +00:00
parent 7e0a1683e6
commit 4d54d87c3e

View file

@ -823,15 +823,17 @@ class SyncHandler(BaseHandler):
# TODO(mjark) Check for new redactions in the state events.
with Measure(self.clock, "compute_state_delta"):
current_state = yield self.get_state_at(
room_id, stream_position=now_token
)
if full_state:
if batch:
state = yield self.store.get_state_for_event(
batch.events[0].event_id
)
else:
state = yield self.get_state_at(
room_id, stream_position=now_token
)
state = current_state
timeline_state = {
(event.type, event.state_key): event
@ -842,6 +844,7 @@ class SyncHandler(BaseHandler):
timeline_contains=timeline_state,
timeline_start=state,
previous={},
current=current_state,
)
elif batch.limited:
state_at_previous_sync = yield self.get_state_at(
@ -861,6 +864,7 @@ class SyncHandler(BaseHandler):
timeline_contains=timeline_state,
timeline_start=state_at_timeline_start,
previous=state_at_previous_sync,
current=current_state,
)
else:
state = {}
@ -920,7 +924,7 @@ def _action_has_highlight(actions):
return False
def _calculate_state(timeline_contains, timeline_start, previous):
def _calculate_state(timeline_contains, timeline_start, previous, current):
"""Works out what state to include in a sync response.
Args:
@ -928,6 +932,7 @@ def _calculate_state(timeline_contains, timeline_start, previous):
timeline_start (dict): state at the start of the timeline
previous (dict): state at the end of the previous sync (or empty dict
if this is an initial sync)
current (dict): state at the end of the timeline
Returns:
dict
@ -938,14 +943,16 @@ def _calculate_state(timeline_contains, timeline_start, previous):
timeline_contains.values(),
previous.values(),
timeline_start.values(),
current.values(),
)
}
c_ids = set(e.event_id for e in current.values())
tc_ids = set(e.event_id for e in timeline_contains.values())
p_ids = set(e.event_id for e in previous.values())
ts_ids = set(e.event_id for e in timeline_start.values())
state_ids = (ts_ids - p_ids) - tc_ids
state_ids = ((c_ids | ts_ids) - p_ids) - tc_ids
evs = (event_id_to_state[e] for e in state_ids)
return {