diff options
Diffstat (limited to 'synapse/state.py')
| -rw-r--r-- | synapse/state.py | 255 |
1 files changed, 198 insertions, 57 deletions
diff --git a/synapse/state.py b/synapse/state.py index 8144fa02b4..80cced351d 100644 --- a/synapse/state.py +++ b/synapse/state.py @@ -18,7 +18,9 @@ from twisted.internet import defer from synapse.util.logutils import log_function from synapse.util.async import run_on_reactor +from synapse.util.expiringcache import ExpiringCache from synapse.api.constants import EventTypes +from synapse.api.errors import AuthError from synapse.events.snapshot import EventContext from collections import namedtuple @@ -36,12 +38,46 @@ def _get_state_key_from_event(event): KeyStateTuple = namedtuple("KeyStateTuple", ("context", "type", "state_key")) +AuthEventTypes = ( + EventTypes.Create, EventTypes.Member, EventTypes.PowerLevels, + EventTypes.JoinRules, +) + + +SIZE_OF_CACHE = 1000 +EVICTION_TIMEOUT_SECONDS = 20 + + +class _StateCacheEntry(object): + def __init__(self, state, state_group, ts): + self.state = state + self.state_group = state_group + + class StateHandler(object): """ Responsible for doing state conflict resolution. """ def __init__(self, hs): + self.clock = hs.get_clock() self.store = hs.get_datastore() + self.hs = hs + + # dict of set of event_ids -> _StateCacheEntry. + self._state_cache = None + + def start_caching(self): + logger.debug("start_caching") + + self._state_cache = ExpiringCache( + cache_name="state_cache", + clock=self.clock, + max_len=SIZE_OF_CACHE, + expiry_ms=EVICTION_TIMEOUT_SECONDS*1000, + reset_expiry_on_get=True, + ) + + self._state_cache.start() @defer.inlineCallbacks def get_current_state(self, room_id, event_type=None, state_key=""): @@ -62,13 +98,22 @@ class StateHandler(object): for e_id, _, _ in events ] - res = yield self.resolve_state_groups(event_ids) + cache = None + if self._state_cache is not None: + cache = self._state_cache.get(frozenset(event_ids), None) + + if cache: + cache.ts = self.clock.time_msec() + state = cache.state + else: + res = yield self.resolve_state_groups(event_ids) + state = res[1] if event_type: - defer.returnValue(res[1].get((event_type, state_key))) + defer.returnValue(state.get((event_type, state_key))) return - defer.returnValue(res[1].values()) + defer.returnValue(state) @defer.inlineCallbacks def compute_event_context(self, event, old_state=None): @@ -95,7 +140,9 @@ class StateHandler(object): context.state_group = None if hasattr(event, "auth_events") and event.auth_events: - auth_ids = zip(*event.auth_events)[0] + auth_ids = self.hs.get_auth().compute_auth_events( + event, context.current_state + ) context.auth_events = { k: v for k, v in context.current_state.items() @@ -141,7 +188,9 @@ class StateHandler(object): event.unsigned["replaces_state"] = replaces.event_id if hasattr(event, "auth_events") and event.auth_events: - auth_ids = zip(*event.auth_events)[0] + auth_ids = self.hs.get_auth().compute_auth_events( + event, context.current_state + ) context.auth_events = { k: v for k, v in context.current_state.items() @@ -163,10 +212,31 @@ class StateHandler(object): first is the name of a state group if one and only one is involved, otherwise `None`. """ + logger.debug("resolve_state_groups event_ids %s", event_ids) + + if self._state_cache is not None: + cache = self._state_cache.get(frozenset(event_ids), None) + if cache and cache.state_group: + cache.ts = self.clock.time_msec() + prev_state = cache.state.get((event_type, state_key), None) + if prev_state: + prev_state = prev_state.event_id + prev_states = [prev_state] + else: + prev_states = [] + defer.returnValue( + (cache.state_group, cache.state, prev_states) + ) + state_groups = yield self.store.get_state_groups( event_ids ) + logger.debug( + "resolve_state_groups state_groups %s", + state_groups.keys() + ) + group_names = set(state_groups.keys()) if len(group_names) == 1: name, state_list = state_groups.items().pop() @@ -181,15 +251,48 @@ class StateHandler(object): else: prev_states = [] + if self._state_cache is not None: + cache = _StateCacheEntry( + state=state, + state_group=name, + ts=self.clock.time_msec() + ) + + self._state_cache[frozenset(event_ids)] = cache + defer.returnValue((name, state, prev_states)) + new_state, prev_states = self._resolve_events( + state_groups.values(), event_type, state_key + ) + + if self._state_cache is not None: + cache = _StateCacheEntry( + state=new_state, + state_group=None, + ts=self.clock.time_msec() + ) + + self._state_cache[frozenset(event_ids)] = cache + + defer.returnValue((None, new_state, prev_states)) + + def resolve_events(self, state_sets, event): + if event.is_state(): + return self._resolve_events( + state_sets, event.type, event.state_key + ) + else: + return self._resolve_events(state_sets) + + def _resolve_events(self, state_sets, event_type=None, state_key=""): state = {} - for group, g_state in state_groups.items(): - for s in g_state: + for st in state_sets: + for e in st: state.setdefault( - (s.type, s.state_key), + (e.type, e.state_key), {} - )[s.event_id] = s + )[e.event_id] = e unconflicted_state = { k: v.values()[0] for k, v in state.items() @@ -210,64 +313,102 @@ class StateHandler(object): else: prev_states = [] + auth_events = { + k: e for k, e in unconflicted_state.items() + if k[0] in AuthEventTypes + } + try: - new_state = {} - new_state.update(unconflicted_state) - for key, events in conflicted_state.items(): - new_state[key] = self._resolve_state_events(events) + resolved_state = self._resolve_state_events( + conflicted_state, auth_events + ) except: logger.exception("Failed to resolve state") raise - defer.returnValue((None, new_state, prev_states)) - - def _get_power_level_from_event_state(self, event, user_id): - if hasattr(event, "old_state_events") and event.old_state_events: - key = (EventTypes.PowerLevels, "", ) - power_level_event = event.old_state_events.get(key) - level = None - if power_level_event: - level = power_level_event.content.get("users", {}).get( - user_id - ) - if not level: - level = power_level_event.content.get("users_default", 0) + new_state = unconflicted_state + new_state.update(resolved_state) - return level - else: - return 0 + return new_state, prev_states @log_function - def _resolve_state_events(self, events): - curr_events = events + def _resolve_state_events(self, conflicted_state, auth_events): + """ This is where we actually decide which of the conflicted state to + use. + + We resolve conflicts in the following order: + 1. power levels + 2. memberships + 3. other events. + """ + resolved_state = {} + power_key = (EventTypes.PowerLevels, "") + if power_key in conflicted_state.items(): + power_levels = conflicted_state[power_key] + resolved_state[power_key] = self._resolve_auth_events(power_levels) + + auth_events.update(resolved_state) + + for key, events in conflicted_state.items(): + if key[0] == EventTypes.JoinRules: + resolved_state[key] = self._resolve_auth_events( + events, + auth_events + ) - new_powers = [ - self._get_power_level_from_event_state(e, e.user_id) - for e in curr_events - ] + auth_events.update(resolved_state) - new_powers = [ - int(p) if p else 0 for p in new_powers - ] + for key, events in conflicted_state.items(): + if key[0] == EventTypes.Member: + resolved_state[key] = self._resolve_auth_events( + events, + auth_events + ) - max_power = max(new_powers) + auth_events.update(resolved_state) - curr_events = [ - z[0] for z in zip(curr_events, new_powers) - if z[1] == max_power - ] + for key, events in conflicted_state.items(): + if key not in resolved_state: + resolved_state[key] = self._resolve_normal_events( + events, auth_events + ) - if not curr_events: - raise RuntimeError("Max didn't get a max?") - elif len(curr_events) == 1: - return curr_events[0] - - # TODO: For now, just choose the one with the largest event_id. - return ( - sorted( - curr_events, - key=lambda e: hashlib.sha1( - e.event_id + e.user_id + e.room_id + e.type - ).hexdigest() - )[0] - ) + return resolved_state + + def _resolve_auth_events(self, events, auth_events): + reverse = [i for i in reversed(self._ordered_events(events))] + + auth_events = dict(auth_events) + + prev_event = reverse[0] + for event in reverse[1:]: + auth_events[(prev_event.type, prev_event.state_key)] = prev_event + try: + # FIXME: hs.get_auth() is bad style, but we need to do it to + # get around circular deps. + self.hs.get_auth().check(event, auth_events) + prev_event = event + except AuthError: + return prev_event + + return event + + def _resolve_normal_events(self, events, auth_events): + for event in self._ordered_events(events): + try: + # FIXME: hs.get_auth() is bad style, but we need to do it to + # get around circular deps. + self.hs.get_auth().check(event, auth_events) + return event + except AuthError: + pass + + # Use the last event (the one with the least depth) if they all fail + # the auth check. + return event + + def _ordered_events(self, events): + def key_func(e): + return -int(e.depth), hashlib.sha1(e.event_id).hexdigest() + + return sorted(events, key=key_func) |