diff options
Diffstat (limited to 'synapse/state')
| -rw-r--r-- | synapse/state/v2.py | 69 |
1 files changed, 37 insertions, 32 deletions
diff --git a/synapse/state/v2.py b/synapse/state/v2.py index cf3045f82e..af03851c71 100644 --- a/synapse/state/v2.py +++ b/synapse/state/v2.py @@ -271,40 +271,41 @@ async def _get_power_level_for_sender( async def _get_auth_chain_difference( room_id: str, state_sets: Sequence[Mapping[Any, str]], - event_map: Dict[str, EventBase], + unpersisted_events: Dict[str, EventBase], state_res_store: StateResolutionStore, ) -> Set[str]: """Compare the auth chains of each state set and return the set of events - that only appear in some but not all of the auth chains. + that only appear in some, but not all of the auth chains. Args: - state_sets - event_map - state_res_store + state_sets: The input state sets we are trying to resolve across. + unpersisted_events: A map from event ID to EventBase containing all unpersisted + events involved in this resolution. + state_res_store: Returns: - Set of event IDs + The auth difference of the given state sets, as a set of event IDs. """ # The `StateResolutionStore.get_auth_chain_difference` function assumes that # all events passed to it (and their auth chains) have been persisted - # previously. This is not the case for any events in the `event_map`, and so - # we need to manually handle those events. + # previously. We need to manually handle any other events that are yet to be + # persisted. # - # We do this by: - # 1. calculating the auth chain difference for the state sets based on the - # events in `event_map` alone - # 2. replacing any events in the state_sets that are also in `event_map` - # with their auth events (recursively), and then calling - # `store.get_auth_chain_difference` as normal - # 3. adding the results of 1 and 2 together. - - # Map from event ID in `event_map` to their auth event IDs, and their auth - # event IDs if they appear in the `event_map`. This is the intersection of - # the event's auth chain with the events in the `event_map` *plus* their + # We do this in three steps: + # 1. Compute the set of unpersisted events belonging to the auth difference. + # 2. Replacing any unpersisted events in the state_sets with their auth events, + # recursively, until the state_sets contain only persisted events. + # Then we call `store.get_auth_chain_difference` as normal, which computes + # the set of persisted events belonging to the auth difference. + # 3. Adding the results of 1 and 2 together. + + # Map from event ID in `unpersisted_events` to their auth event IDs, and their auth + # event IDs if they appear in the `unpersisted_events`. This is the intersection of + # the event's auth chain with the events in `unpersisted_events` *plus* their # auth event IDs. events_to_auth_chain: Dict[str, Set[str]] = {} - for event in event_map.values(): + for event in unpersisted_events.values(): chain = {event.event_id} events_to_auth_chain[event.event_id] = chain @@ -312,16 +313,16 @@ async def _get_auth_chain_difference( while to_search: for auth_id in to_search.pop().auth_event_ids(): chain.add(auth_id) - auth_event = event_map.get(auth_id) + auth_event = unpersisted_events.get(auth_id) if auth_event: to_search.append(auth_event) - # We now a) calculate the auth chain difference for the unpersisted events - # and b) work out the state sets to pass to the store. + # We now 1) calculate the auth chain difference for the unpersisted events + # and 2) work out the state sets to pass to the store. # - # Note: If the `event_map` is empty (which is the common case), we can do a + # Note: If there are no `unpersisted_events` (which is the common case), we can do a # much simpler calculation. - if event_map: + if unpersisted_events: # The list of state sets to pass to the store, where each state set is a set # of the event ids making up the state. This is similar to `state_sets`, # except that (a) we only have event ids, not the complete @@ -344,14 +345,18 @@ async def _get_auth_chain_difference( for event_id in state_set.values(): event_chain = events_to_auth_chain.get(event_id) if event_chain is not None: - # We have an event in `event_map`. We add all the auth - # events that it references (that aren't also in `event_map`). - set_ids.update(e for e in event_chain if e not in event_map) + # We have an unpersisted event. We add all the auth + # events that it references which are also unpersisted. + set_ids.update( + e for e in event_chain if e not in unpersisted_events + ) # We also add the full chain of unpersisted event IDs # referenced by this state set, so that we can work out the # auth chain difference of the unpersisted events. - unpersisted_ids.update(e for e in event_chain if e in event_map) + unpersisted_ids.update( + e for e in event_chain if e in unpersisted_events + ) else: set_ids.add(event_id) @@ -361,15 +366,15 @@ async def _get_auth_chain_difference( union = unpersisted_set_ids[0].union(*unpersisted_set_ids[1:]) intersection = unpersisted_set_ids[0].intersection(*unpersisted_set_ids[1:]) - difference_from_event_map: Collection[str] = union - intersection + auth_difference_unpersisted_part: Collection[str] = union - intersection else: - difference_from_event_map = () + auth_difference_unpersisted_part = () state_sets_ids = [set(state_set.values()) for state_set in state_sets] difference = await state_res_store.get_auth_chain_difference( room_id, state_sets_ids ) - difference.update(difference_from_event_map) + difference.update(auth_difference_unpersisted_part) return difference |