946 lines
		
	
	
		
			34 KiB
		
	
	
	
		
			Python
		
	
	
			
		
		
	
	
			946 lines
		
	
	
		
			34 KiB
		
	
	
	
		
			Python
		
	
	
| # Copyright 2014-2016 OpenMarket Ltd
 | |
| # Copyright 2018 New Vector Ltd
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| #
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| # Licensed under the Apache License, Version 2.0 (the "License");
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| # you may not use this file except in compliance with the License.
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| # You may obtain a copy of the License at
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| #
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| #     http://www.apache.org/licenses/LICENSE-2.0
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| #
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| # Unless required by applicable law or agreed to in writing, software
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| # distributed under the License is distributed on an "AS IS" BASIS,
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| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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| # See the License for the specific language governing permissions and
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| # limitations under the License.
 | |
| import heapq
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| import logging
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| from collections import ChainMap, defaultdict
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| from typing import (
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|     TYPE_CHECKING,
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|     Any,
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|     Awaitable,
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|     Callable,
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|     Collection,
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|     DefaultDict,
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|     Dict,
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|     FrozenSet,
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|     List,
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|     Mapping,
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|     Optional,
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|     Sequence,
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|     Set,
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|     Tuple,
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| )
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| 
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| import attr
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| from frozendict import frozendict
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| from prometheus_client import Counter, Histogram
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| 
 | |
| from synapse.api.constants import EventTypes
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| from synapse.api.room_versions import KNOWN_ROOM_VERSIONS, StateResolutionVersions
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| from synapse.events import EventBase
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| from synapse.events.snapshot import EventContext
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| from synapse.logging.context import ContextResourceUsage
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| from synapse.replication.http.state import ReplicationUpdateCurrentStateRestServlet
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| from synapse.state import v1, v2
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| from synapse.storage.databases.main.events_worker import EventRedactBehaviour
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| from synapse.types import StateMap
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| from synapse.types.state import StateFilter
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| from synapse.util.async_helpers import Linearizer
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| from synapse.util.caches.expiringcache import ExpiringCache
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| from synapse.util.metrics import Measure, measure_func
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| 
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| if TYPE_CHECKING:
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|     from synapse.server import HomeServer
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|     from synapse.storage.controllers import StateStorageController
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|     from synapse.storage.databases.main import DataStore
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| 
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| logger = logging.getLogger(__name__)
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| metrics_logger = logging.getLogger("synapse.state.metrics")
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| 
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| # Metrics for number of state groups involved in a resolution.
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| state_groups_histogram = Histogram(
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|     "synapse_state_number_state_groups_in_resolution",
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|     "Number of state groups used when performing a state resolution",
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|     buckets=(1, 2, 3, 5, 7, 10, 15, 20, 50, 100, 200, 500, "+Inf"),
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| )
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| 
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| 
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| EVICTION_TIMEOUT_SECONDS = 60 * 60
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| 
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| 
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| _NEXT_STATE_ID = 1
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| 
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| POWER_KEY = (EventTypes.PowerLevels, "")
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| 
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| 
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| def _gen_state_id() -> str:
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|     global _NEXT_STATE_ID
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|     s = "X%d" % (_NEXT_STATE_ID,)
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|     _NEXT_STATE_ID += 1
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|     return s
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| 
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| 
 | |
| class _StateCacheEntry:
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|     __slots__ = ["_state", "state_group", "prev_group", "delta_ids"]
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| 
 | |
|     def __init__(
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|         self,
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|         state: Optional[StateMap[str]],
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|         state_group: Optional[int],
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|         prev_group: Optional[int] = None,
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|         delta_ids: Optional[StateMap[str]] = None,
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|     ):
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|         if state is None and state_group is None and prev_group is None:
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|             raise Exception("One of state, state_group or prev_group must be not None")
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| 
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|         if prev_group is not None and delta_ids is None:
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|             raise Exception("If prev_group is set so must delta_ids")
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| 
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|         # A map from (type, state_key) to event_id.
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|         #
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|         # This can be None if we have a `state_group` (as then we can fetch the
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|         # state from the DB.)
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|         self._state = frozendict(state) if state is not None else None
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| 
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|         # the ID of a state group if one and only one is involved.
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|         # otherwise, None otherwise?
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|         self.state_group = state_group
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| 
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|         self.prev_group = prev_group
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|         self.delta_ids = frozendict(delta_ids) if delta_ids is not None else None
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| 
 | |
|     async def get_state(
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|         self,
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|         state_storage: "StateStorageController",
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|         state_filter: Optional["StateFilter"] = None,
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|     ) -> StateMap[str]:
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|         """Get the state map for this entry, either from the in-memory state or
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|         looking up the state group in the DB.
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|         """
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| 
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|         if self._state is not None:
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|             return self._state
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| 
 | |
|         if self.state_group is not None:
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|             return await state_storage.get_state_ids_for_group(
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|                 self.state_group, state_filter
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|             )
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| 
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|         assert self.prev_group is not None and self.delta_ids is not None
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| 
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|         prev_state = await state_storage.get_state_ids_for_group(
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|             self.prev_group, state_filter
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|         )
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| 
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|         # ChainMap expects MutableMapping, but since we're using it immutably
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|         # its safe to give it immutable maps.
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|         return ChainMap(self.delta_ids, prev_state)  # type: ignore[arg-type]
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| 
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|     def set_state_group(self, state_group: int) -> None:
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|         """Update the state group assigned to this state (e.g. after we've
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|         persisted it).
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| 
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|         Note: this will cause the cache entry to drop any stored state.
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|         """
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| 
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|         self.state_group = state_group
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| 
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|         # We clear out the state as we know longer need to explicitly keep it in
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|         # the `state_cache` (as the store state group cache will do that).
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|         self._state = None
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| 
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|     def __len__(self) -> int:
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|         # The len should be used to estimate how large this cache entry is, for
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|         # cache eviction purposes. This is why it's fine to return 1 if we're
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|         # not storing any state.
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| 
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|         length = 0
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| 
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|         if self._state:
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|             length += len(self._state)
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| 
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|         if self.delta_ids:
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|             length += len(self.delta_ids)
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| 
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|         return length or 1  # Make sure its not 0.
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| 
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| 
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| class StateHandler:
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|     """Fetches bits of state from the stores, and does state resolution
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|     where necessary
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|     """
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| 
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|     def __init__(self, hs: "HomeServer"):
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|         self.clock = hs.get_clock()
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|         self.store = hs.get_datastores().main
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|         self._state_storage_controller = hs.get_storage_controllers().state
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|         self.hs = hs
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|         self._state_resolution_handler = hs.get_state_resolution_handler()
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|         self._storage_controllers = hs.get_storage_controllers()
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|         self._events_shard_config = hs.config.worker.events_shard_config
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|         self._instance_name = hs.get_instance_name()
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| 
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|         self._update_current_state_client = (
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|             ReplicationUpdateCurrentStateRestServlet.make_client(hs)
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|         )
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| 
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|     async def compute_state_after_events(
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|         self,
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|         room_id: str,
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|         event_ids: Collection[str],
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|         state_filter: Optional[StateFilter] = None,
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|         await_full_state: bool = True,
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|     ) -> StateMap[str]:
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|         """Fetch the state after each of the given event IDs. Resolve them and return.
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| 
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|         This is typically used where `event_ids` is a collection of forward extremities
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|         in a room, intended to become the `prev_events` of a new event E. If so, the
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|         return value of this function represents the state before E.
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| 
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|         Args:
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|             room_id: the room_id containing the given events.
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|             event_ids: the events whose state should be fetched and resolved.
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|             await_full_state: if `True`, will block if we do not yet have complete state
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|                 at these events and `state_filter` is not satisfied by partial state.
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|                 Defaults to `True`.
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| 
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|         Returns:
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|             the state dict (a mapping from (event_type, state_key) -> event_id) which
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|             holds the resolution of the states after the given event IDs.
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|         """
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|         logger.debug("calling resolve_state_groups from compute_state_after_events")
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|         if (
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|             await_full_state
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|             and state_filter
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|             and not state_filter.must_await_full_state(self.hs.is_mine_id)
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|         ):
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|             await_full_state = False
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|         ret = await self.resolve_state_groups_for_events(
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|             room_id, event_ids, await_full_state
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|         )
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|         return await ret.get_state(self._state_storage_controller, state_filter)
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| 
 | |
|     async def get_current_user_ids_in_room(
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|         self, room_id: str, latest_event_ids: List[str]
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|     ) -> Set[str]:
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|         """
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|         Get the users IDs who are currently in a room.
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| 
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|         Note: This is much slower than using the equivalent method
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|         `DataStore.get_users_in_room` or `DataStore.get_users_in_room_with_profiles`,
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|         so this should only be used when wanting the users at a particular point
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|         in the room.
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| 
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|         Args:
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|             room_id: The ID of the room.
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|             latest_event_ids: Precomputed list of latest event IDs. Will be computed if None.
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|         Returns:
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|             Set of user IDs in the room.
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|         """
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| 
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|         assert latest_event_ids is not None
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| 
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|         logger.debug("calling resolve_state_groups from get_current_user_ids_in_room")
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|         entry = await self.resolve_state_groups_for_events(room_id, latest_event_ids)
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|         state = await entry.get_state(self._state_storage_controller, StateFilter.all())
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|         return await self.store.get_joined_user_ids_from_state(room_id, state)
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| 
 | |
|     async def get_hosts_in_room_at_events(
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|         self, room_id: str, event_ids: Collection[str]
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|     ) -> FrozenSet[str]:
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|         """Get the hosts that were in a room at the given event ids
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| 
 | |
|         Args:
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|             room_id:
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|             event_ids:
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| 
 | |
|         Returns:
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|             The hosts in the room at the given events
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|         """
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|         entry = await self.resolve_state_groups_for_events(room_id, event_ids)
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|         state = await entry.get_state(self._state_storage_controller, StateFilter.all())
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|         return await self.store.get_joined_hosts(room_id, state, entry)
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| 
 | |
|     async def compute_event_context(
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|         self,
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|         event: EventBase,
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|         state_ids_before_event: Optional[StateMap[str]] = None,
 | |
|         partial_state: Optional[bool] = None,
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|     ) -> EventContext:
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|         """Build an EventContext structure for a non-outlier event.
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| 
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|         (for an outlier, call EventContext.for_outlier directly)
 | |
| 
 | |
|         This works out what the current state should be for the event, and
 | |
|         generates a new state group if necessary.
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| 
 | |
|         Args:
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|             event:
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|             state_ids_before_event: The event ids of the state before the event if
 | |
|                 it can't be calculated from existing events. This is normally
 | |
|                 only specified when receiving an event from federation where we
 | |
|                 don't have the prev events, e.g. when backfilling.
 | |
|             partial_state:
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|                 `True` if `state_ids_before_event` is partial and omits non-critical
 | |
|                 membership events.
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|                 `False` if `state_ids_before_event` is the full state.
 | |
|                 `None` when `state_ids_before_event` is not provided. In this case, the
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|                 flag will be calculated based on `event`'s prev events.
 | |
|         Returns:
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|             The event context.
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| 
 | |
|         Raises:
 | |
|             RuntimeError if `state_ids_before_event` is not provided and one or more
 | |
|                 prev events are missing or outliers.
 | |
|         """
 | |
| 
 | |
|         assert not event.internal_metadata.is_outlier()
 | |
| 
 | |
|         #
 | |
|         # first of all, figure out the state before the event, unless we
 | |
|         # already have it.
 | |
|         #
 | |
|         if state_ids_before_event:
 | |
|             # if we're given the state before the event, then we use that
 | |
|             state_group_before_event_prev_group = None
 | |
|             deltas_to_state_group_before_event = None
 | |
| 
 | |
|             # .. though we need to get a state group for it.
 | |
|             state_group_before_event = (
 | |
|                 await self._state_storage_controller.store_state_group(
 | |
|                     event.event_id,
 | |
|                     event.room_id,
 | |
|                     prev_group=None,
 | |
|                     delta_ids=None,
 | |
|                     current_state_ids=state_ids_before_event,
 | |
|                 )
 | |
|             )
 | |
| 
 | |
|             # the partial_state flag must be provided
 | |
|             assert partial_state is not None
 | |
|         else:
 | |
|             # otherwise, we'll need to resolve the state across the prev_events.
 | |
| 
 | |
|             # partial_state should not be set explicitly in this case:
 | |
|             # we work it out dynamically
 | |
|             assert partial_state is None
 | |
| 
 | |
|             # if any of the prev-events have partial state, so do we.
 | |
|             # (This is slightly racy - the prev-events might get fixed up before we use
 | |
|             # their states - but I don't think that really matters; it just means we
 | |
|             # might redundantly recalculate the state for this event later.)
 | |
|             prev_event_ids = event.prev_event_ids()
 | |
|             incomplete_prev_events = await self.store.get_partial_state_events(
 | |
|                 prev_event_ids
 | |
|             )
 | |
|             partial_state = any(incomplete_prev_events.values())
 | |
|             if partial_state:
 | |
|                 logger.debug(
 | |
|                     "New/incoming event %s refers to prev_events %s with partial state",
 | |
|                     event.event_id,
 | |
|                     [k for (k, v) in incomplete_prev_events.items() if v],
 | |
|                 )
 | |
| 
 | |
|             logger.debug("calling resolve_state_groups from compute_event_context")
 | |
|             # we've already taken into account partial state, so no need to wait for
 | |
|             # complete state here.
 | |
|             entry = await self.resolve_state_groups_for_events(
 | |
|                 event.room_id,
 | |
|                 event.prev_event_ids(),
 | |
|                 await_full_state=False,
 | |
|             )
 | |
| 
 | |
|             state_group_before_event_prev_group = entry.prev_group
 | |
|             deltas_to_state_group_before_event = entry.delta_ids
 | |
|             state_ids_before_event = None
 | |
| 
 | |
|             # We make sure that we have a state group assigned to the state.
 | |
|             if entry.state_group is None:
 | |
|                 # store_state_group requires us to have either a previous state group
 | |
|                 # (with deltas) or the complete state map. So, if we don't have a
 | |
|                 # previous state group, load the complete state map now.
 | |
|                 if state_group_before_event_prev_group is None:
 | |
|                     state_ids_before_event = await entry.get_state(
 | |
|                         self._state_storage_controller, StateFilter.all()
 | |
|                     )
 | |
| 
 | |
|                 state_group_before_event = (
 | |
|                     await self._state_storage_controller.store_state_group(
 | |
|                         event.event_id,
 | |
|                         event.room_id,
 | |
|                         prev_group=state_group_before_event_prev_group,
 | |
|                         delta_ids=deltas_to_state_group_before_event,
 | |
|                         current_state_ids=state_ids_before_event,
 | |
|                     )
 | |
|                 )
 | |
|                 entry.set_state_group(state_group_before_event)
 | |
|             else:
 | |
|                 state_group_before_event = entry.state_group
 | |
| 
 | |
|         #
 | |
|         # now if it's not a state event, we're done
 | |
|         #
 | |
| 
 | |
|         if not event.is_state():
 | |
|             return EventContext.with_state(
 | |
|                 storage=self._storage_controllers,
 | |
|                 state_group_before_event=state_group_before_event,
 | |
|                 state_group=state_group_before_event,
 | |
|                 state_delta_due_to_event={},
 | |
|                 prev_group=state_group_before_event_prev_group,
 | |
|                 delta_ids=deltas_to_state_group_before_event,
 | |
|                 partial_state=partial_state,
 | |
|             )
 | |
| 
 | |
|         #
 | |
|         # otherwise, we'll need to create a new state group for after the event
 | |
|         #
 | |
| 
 | |
|         key = (event.type, event.state_key)
 | |
| 
 | |
|         if state_ids_before_event is not None:
 | |
|             replaces = state_ids_before_event.get(key)
 | |
|         else:
 | |
|             replaces_state_map = await entry.get_state(
 | |
|                 self._state_storage_controller, StateFilter.from_types([key])
 | |
|             )
 | |
|             replaces = replaces_state_map.get(key)
 | |
| 
 | |
|         if replaces and replaces != event.event_id:
 | |
|             event.unsigned["replaces_state"] = replaces
 | |
| 
 | |
|         delta_ids = {key: event.event_id}
 | |
| 
 | |
|         state_group_after_event = (
 | |
|             await self._state_storage_controller.store_state_group(
 | |
|                 event.event_id,
 | |
|                 event.room_id,
 | |
|                 prev_group=state_group_before_event,
 | |
|                 delta_ids=delta_ids,
 | |
|                 current_state_ids=None,
 | |
|             )
 | |
|         )
 | |
| 
 | |
|         return EventContext.with_state(
 | |
|             storage=self._storage_controllers,
 | |
|             state_group=state_group_after_event,
 | |
|             state_group_before_event=state_group_before_event,
 | |
|             state_delta_due_to_event=delta_ids,
 | |
|             prev_group=state_group_before_event,
 | |
|             delta_ids=delta_ids,
 | |
|             partial_state=partial_state,
 | |
|         )
 | |
| 
 | |
|     async def compute_event_context_for_batched(
 | |
|         self,
 | |
|         event: EventBase,
 | |
|         state_ids_before_event: StateMap[str],
 | |
|         current_state_group: int,
 | |
|     ) -> EventContext:
 | |
|         """
 | |
|         Generate an event context for an event that has not yet been persisted to the
 | |
|         database. Intended for use with events that are created to be persisted in a batch.
 | |
|         Args:
 | |
|             event: the event the context is being computed for
 | |
|             state_ids_before_event: a state map consisting of the state ids of the events
 | |
|             created prior to this event.
 | |
|             current_state_group: the current state group before the event.
 | |
|         """
 | |
|         state_group_before_event_prev_group = None
 | |
|         deltas_to_state_group_before_event = None
 | |
| 
 | |
|         state_group_before_event = current_state_group
 | |
| 
 | |
|         # if the event is not state, we are set
 | |
|         if not event.is_state():
 | |
|             return EventContext.with_state(
 | |
|                 storage=self._storage_controllers,
 | |
|                 state_group_before_event=state_group_before_event,
 | |
|                 state_group=state_group_before_event,
 | |
|                 state_delta_due_to_event={},
 | |
|                 prev_group=state_group_before_event_prev_group,
 | |
|                 delta_ids=deltas_to_state_group_before_event,
 | |
|                 partial_state=False,
 | |
|             )
 | |
| 
 | |
|         # otherwise, we'll need to create a new state group for after the event
 | |
|         key = (event.type, event.state_key)
 | |
| 
 | |
|         if state_ids_before_event is not None:
 | |
|             replaces = state_ids_before_event.get(key)
 | |
| 
 | |
|         if replaces and replaces != event.event_id:
 | |
|             event.unsigned["replaces_state"] = replaces
 | |
| 
 | |
|         delta_ids = {key: event.event_id}
 | |
| 
 | |
|         state_group_after_event = (
 | |
|             await self._state_storage_controller.store_state_group(
 | |
|                 event.event_id,
 | |
|                 event.room_id,
 | |
|                 prev_group=state_group_before_event,
 | |
|                 delta_ids=delta_ids,
 | |
|                 current_state_ids=None,
 | |
|             )
 | |
|         )
 | |
| 
 | |
|         return EventContext.with_state(
 | |
|             storage=self._storage_controllers,
 | |
|             state_group=state_group_after_event,
 | |
|             state_group_before_event=state_group_before_event,
 | |
|             state_delta_due_to_event=delta_ids,
 | |
|             prev_group=state_group_before_event,
 | |
|             delta_ids=delta_ids,
 | |
|             partial_state=False,
 | |
|         )
 | |
| 
 | |
|     @measure_func()
 | |
|     async def resolve_state_groups_for_events(
 | |
|         self, room_id: str, event_ids: Collection[str], await_full_state: bool = True
 | |
|     ) -> _StateCacheEntry:
 | |
|         """Given a list of event_ids this method fetches the state at each
 | |
|         event, resolves conflicts between them and returns them.
 | |
| 
 | |
|         Args:
 | |
|             room_id
 | |
|             event_ids
 | |
|             await_full_state: if true, will block if we do not yet have complete
 | |
|                state at these events.
 | |
| 
 | |
|         Returns:
 | |
|             The resolved state
 | |
| 
 | |
|         Raises:
 | |
|             RuntimeError if we don't have a state group for one or more of the events
 | |
|                (ie. they are outliers or unknown)
 | |
|         """
 | |
|         logger.debug("resolve_state_groups event_ids %s", event_ids)
 | |
| 
 | |
|         state_groups = await self._state_storage_controller.get_state_group_for_events(
 | |
|             event_ids, await_full_state=await_full_state
 | |
|         )
 | |
| 
 | |
|         state_group_ids = state_groups.values()
 | |
| 
 | |
|         # check if each event has same state group id, if so there's no state to resolve
 | |
|         state_group_ids_set = set(state_group_ids)
 | |
|         if len(state_group_ids_set) == 1:
 | |
|             (state_group_id,) = state_group_ids_set
 | |
|             (
 | |
|                 prev_group,
 | |
|                 delta_ids,
 | |
|             ) = await self._state_storage_controller.get_state_group_delta(
 | |
|                 state_group_id
 | |
|             )
 | |
|             return _StateCacheEntry(
 | |
|                 state=None,
 | |
|                 state_group=state_group_id,
 | |
|                 prev_group=prev_group,
 | |
|                 delta_ids=delta_ids,
 | |
|             )
 | |
|         elif len(state_group_ids_set) == 0:
 | |
|             return _StateCacheEntry(state={}, state_group=None)
 | |
| 
 | |
|         room_version = await self.store.get_room_version_id(room_id)
 | |
| 
 | |
|         state_to_resolve = await self._state_storage_controller.get_state_for_groups(
 | |
|             state_group_ids_set
 | |
|         )
 | |
| 
 | |
|         result = await self._state_resolution_handler.resolve_state_groups(
 | |
|             room_id,
 | |
|             room_version,
 | |
|             state_to_resolve,
 | |
|             None,
 | |
|             state_res_store=StateResolutionStore(self.store),
 | |
|         )
 | |
|         return result
 | |
| 
 | |
|     async def update_current_state(self, room_id: str) -> None:
 | |
|         """Recalculates the current state for a room, and persists it.
 | |
| 
 | |
|         Raises:
 | |
|             SynapseError(502): if all attempts to connect to the event persister worker
 | |
|                 fail
 | |
|         """
 | |
|         writer_instance = self._events_shard_config.get_instance(room_id)
 | |
|         if writer_instance != self._instance_name:
 | |
|             await self._update_current_state_client(
 | |
|                 instance_name=writer_instance,
 | |
|                 room_id=room_id,
 | |
|             )
 | |
|             return
 | |
| 
 | |
|         assert self._storage_controllers.persistence is not None
 | |
|         await self._storage_controllers.persistence.update_current_state(room_id)
 | |
| 
 | |
| 
 | |
| @attr.s(slots=True, auto_attribs=True)
 | |
| class _StateResMetrics:
 | |
|     """Keeps track of some usage metrics about state res."""
 | |
| 
 | |
|     # System and User CPU time, in seconds
 | |
|     cpu_time: float = 0.0
 | |
| 
 | |
|     # time spent on database transactions (excluding scheduling time). This roughly
 | |
|     # corresponds to the amount of work done on the db server, excluding event fetches.
 | |
|     db_time: float = 0.0
 | |
| 
 | |
|     # number of events fetched from the db.
 | |
|     db_events: int = 0
 | |
| 
 | |
| 
 | |
| _biggest_room_by_cpu_counter = Counter(
 | |
|     "synapse_state_res_cpu_for_biggest_room_seconds",
 | |
|     "CPU time spent performing state resolution for the single most expensive "
 | |
|     "room for state resolution",
 | |
| )
 | |
| _biggest_room_by_db_counter = Counter(
 | |
|     "synapse_state_res_db_for_biggest_room_seconds",
 | |
|     "Database time spent performing state resolution for the single most "
 | |
|     "expensive room for state resolution",
 | |
| )
 | |
| 
 | |
| _cpu_times = Histogram(
 | |
|     "synapse_state_res_cpu_for_all_rooms_seconds",
 | |
|     "CPU time (utime+stime) spent computing a single state resolution",
 | |
| )
 | |
| _db_times = Histogram(
 | |
|     "synapse_state_res_db_for_all_rooms_seconds",
 | |
|     "Database time spent computing a single state resolution",
 | |
| )
 | |
| 
 | |
| 
 | |
| class StateResolutionHandler:
 | |
|     """Responsible for doing state conflict resolution.
 | |
| 
 | |
|     Note that the storage layer depends on this handler, so all functions must
 | |
|     be storage-independent.
 | |
|     """
 | |
| 
 | |
|     def __init__(self, hs: "HomeServer"):
 | |
|         self.clock = hs.get_clock()
 | |
| 
 | |
|         self.resolve_linearizer = Linearizer(name="state_resolve_lock")
 | |
| 
 | |
|         # dict of set of event_ids -> _StateCacheEntry.
 | |
|         self._state_cache: ExpiringCache[
 | |
|             FrozenSet[int], _StateCacheEntry
 | |
|         ] = ExpiringCache(
 | |
|             cache_name="state_cache",
 | |
|             clock=self.clock,
 | |
|             max_len=100000,
 | |
|             expiry_ms=EVICTION_TIMEOUT_SECONDS * 1000,
 | |
|             iterable=True,
 | |
|             reset_expiry_on_get=True,
 | |
|         )
 | |
| 
 | |
|         #
 | |
|         # stuff for tracking time spent on state-res by room
 | |
|         #
 | |
| 
 | |
|         # tracks the amount of work done on state res per room
 | |
|         self._state_res_metrics: DefaultDict[str, _StateResMetrics] = defaultdict(
 | |
|             _StateResMetrics
 | |
|         )
 | |
| 
 | |
|         self.clock.looping_call(self._report_metrics, 120 * 1000)
 | |
| 
 | |
|     async def resolve_state_groups(
 | |
|         self,
 | |
|         room_id: str,
 | |
|         room_version: str,
 | |
|         state_groups_ids: Mapping[int, StateMap[str]],
 | |
|         event_map: Optional[Dict[str, EventBase]],
 | |
|         state_res_store: "StateResolutionStore",
 | |
|     ) -> _StateCacheEntry:
 | |
|         """Resolves conflicts between a set of state groups
 | |
| 
 | |
|         Always generates a new state group (unless we hit the cache), so should
 | |
|         not be called for a single state group
 | |
| 
 | |
|         Args:
 | |
|             room_id: room we are resolving for (used for logging and sanity checks)
 | |
|             room_version: version of the room
 | |
|             state_groups_ids:
 | |
|                 A map from state group id to the state in that state group
 | |
|                 (where 'state' is a map from state key to event id)
 | |
| 
 | |
|             event_map:
 | |
|                 a dict from event_id to event, for any events that we happen to
 | |
|                 have in flight (eg, those currently being persisted). This will be
 | |
|                 used as a starting point for finding the state we need; any missing
 | |
|                 events will be requested via state_res_store.
 | |
| 
 | |
|                 If None, all events will be fetched via state_res_store.
 | |
| 
 | |
|             state_res_store
 | |
| 
 | |
|         Returns:
 | |
|             The resolved state
 | |
|         """
 | |
|         group_names = frozenset(state_groups_ids.keys())
 | |
| 
 | |
|         async with self.resolve_linearizer.queue(group_names):
 | |
|             cache = self._state_cache.get(group_names, None)
 | |
|             if cache:
 | |
|                 return cache
 | |
| 
 | |
|             logger.info(
 | |
|                 "Resolving state for %s with groups %s",
 | |
|                 room_id,
 | |
|                 list(group_names),
 | |
|             )
 | |
| 
 | |
|             state_groups_histogram.observe(len(state_groups_ids))
 | |
| 
 | |
|             new_state = await self.resolve_events_with_store(
 | |
|                 room_id,
 | |
|                 room_version,
 | |
|                 list(state_groups_ids.values()),
 | |
|                 event_map=event_map,
 | |
|                 state_res_store=state_res_store,
 | |
|             )
 | |
| 
 | |
|             # if the new state matches any of the input state groups, we can
 | |
|             # use that state group again. Otherwise we will generate a state_id
 | |
|             # which will be used as a cache key for future resolutions, but
 | |
|             # not get persisted.
 | |
| 
 | |
|             with Measure(self.clock, "state.create_group_ids"):
 | |
|                 cache = _make_state_cache_entry(new_state, state_groups_ids)
 | |
| 
 | |
|             self._state_cache[group_names] = cache
 | |
| 
 | |
|             return cache
 | |
| 
 | |
|     async def resolve_events_with_store(
 | |
|         self,
 | |
|         room_id: str,
 | |
|         room_version: str,
 | |
|         state_sets: Sequence[StateMap[str]],
 | |
|         event_map: Optional[Dict[str, EventBase]],
 | |
|         state_res_store: "StateResolutionStore",
 | |
|     ) -> StateMap[str]:
 | |
|         """
 | |
|         Args:
 | |
|             room_id: the room we are working in
 | |
| 
 | |
|             room_version: Version of the room
 | |
| 
 | |
|             state_sets: List of dicts of (type, state_key) -> event_id,
 | |
|                 which are the different state groups to resolve.
 | |
| 
 | |
|             event_map:
 | |
|                 a dict from event_id to event, for any events that we happen to
 | |
|                 have in flight (eg, those currently being persisted). This will be
 | |
|                 used as a starting point for finding the state we need; any missing
 | |
|                 events will be requested via state_map_factory.
 | |
| 
 | |
|                 If None, all events will be fetched via state_res_store.
 | |
| 
 | |
|             state_res_store: a place to fetch events from
 | |
| 
 | |
|         Returns:
 | |
|             a map from (type, state_key) to event_id.
 | |
|         """
 | |
|         try:
 | |
|             with Measure(self.clock, "state._resolve_events") as m:
 | |
|                 room_version_obj = KNOWN_ROOM_VERSIONS[room_version]
 | |
|                 if room_version_obj.state_res == StateResolutionVersions.V1:
 | |
|                     return await v1.resolve_events_with_store(
 | |
|                         room_id,
 | |
|                         room_version_obj,
 | |
|                         state_sets,
 | |
|                         event_map,
 | |
|                         state_res_store.get_events,
 | |
|                     )
 | |
|                 else:
 | |
|                     return await v2.resolve_events_with_store(
 | |
|                         self.clock,
 | |
|                         room_id,
 | |
|                         room_version_obj,
 | |
|                         state_sets,
 | |
|                         event_map,
 | |
|                         state_res_store,
 | |
|                     )
 | |
|         finally:
 | |
|             self._record_state_res_metrics(room_id, m.get_resource_usage())
 | |
| 
 | |
|     def _record_state_res_metrics(
 | |
|         self, room_id: str, rusage: ContextResourceUsage
 | |
|     ) -> None:
 | |
|         room_metrics = self._state_res_metrics[room_id]
 | |
|         room_metrics.cpu_time += rusage.ru_utime + rusage.ru_stime
 | |
|         room_metrics.db_time += rusage.db_txn_duration_sec
 | |
|         room_metrics.db_events += rusage.evt_db_fetch_count
 | |
| 
 | |
|         _cpu_times.observe(rusage.ru_utime + rusage.ru_stime)
 | |
|         _db_times.observe(rusage.db_txn_duration_sec)
 | |
| 
 | |
|     def _report_metrics(self) -> None:
 | |
|         if not self._state_res_metrics:
 | |
|             # no state res has happened since the last iteration: don't bother logging.
 | |
|             return
 | |
| 
 | |
|         self._report_biggest(
 | |
|             lambda i: i.cpu_time,
 | |
|             "CPU time",
 | |
|             _biggest_room_by_cpu_counter,
 | |
|         )
 | |
| 
 | |
|         self._report_biggest(
 | |
|             lambda i: i.db_time,
 | |
|             "DB time",
 | |
|             _biggest_room_by_db_counter,
 | |
|         )
 | |
| 
 | |
|         self._state_res_metrics.clear()
 | |
| 
 | |
|     def _report_biggest(
 | |
|         self,
 | |
|         extract_key: Callable[[_StateResMetrics], Any],
 | |
|         metric_name: str,
 | |
|         prometheus_counter_metric: Counter,
 | |
|     ) -> None:
 | |
|         """Report metrics on the biggest rooms for state res
 | |
| 
 | |
|         Args:
 | |
|             extract_key: a callable which, given a _StateResMetrics, extracts a single
 | |
|                 metric to sort by.
 | |
|             metric_name: the name of the metric we have extracted, for the log line
 | |
|             prometheus_counter_metric: a prometheus metric recording the sum of the
 | |
|                 the extracted metric
 | |
|         """
 | |
|         n_to_log = 10
 | |
|         if not metrics_logger.isEnabledFor(logging.DEBUG):
 | |
|             # only need the most expensive if we don't have debug logging, which
 | |
|             # allows nlargest() to degrade to max()
 | |
|             n_to_log = 1
 | |
| 
 | |
|         items = self._state_res_metrics.items()
 | |
| 
 | |
|         # log the N biggest rooms
 | |
|         biggest: List[Tuple[str, _StateResMetrics]] = heapq.nlargest(
 | |
|             n_to_log, items, key=lambda i: extract_key(i[1])
 | |
|         )
 | |
|         metrics_logger.debug(
 | |
|             "%i biggest rooms for state-res by %s: %s",
 | |
|             len(biggest),
 | |
|             metric_name,
 | |
|             ["%s (%gs)" % (r, extract_key(m)) for (r, m) in biggest],
 | |
|         )
 | |
| 
 | |
|         # report info on the single biggest to prometheus
 | |
|         _, biggest_metrics = biggest[0]
 | |
|         prometheus_counter_metric.inc(extract_key(biggest_metrics))
 | |
| 
 | |
| 
 | |
| def _make_state_cache_entry(
 | |
|     new_state: StateMap[str], state_groups_ids: Mapping[int, StateMap[str]]
 | |
| ) -> _StateCacheEntry:
 | |
|     """Given a resolved state, and a set of input state groups, pick one to base
 | |
|     a new state group on (if any), and return an appropriately-constructed
 | |
|     _StateCacheEntry.
 | |
| 
 | |
|     Args:
 | |
|         new_state: resolved state map (mapping from (type, state_key) to event_id)
 | |
| 
 | |
|         state_groups_ids:
 | |
|             map from state group id to the state in that state group (where
 | |
|             'state' is a map from state key to event id)
 | |
| 
 | |
|     Returns:
 | |
|         The cache entry.
 | |
|     """
 | |
|     # if the new state matches any of the input state groups, we can
 | |
|     # use that state group again. Otherwise we will generate a state_id
 | |
|     # which will be used as a cache key for future resolutions, but
 | |
|     # not get persisted.
 | |
| 
 | |
|     # first look for exact matches
 | |
|     new_state_event_ids = set(new_state.values())
 | |
|     for sg, state in state_groups_ids.items():
 | |
|         if len(new_state_event_ids) != len(state):
 | |
|             continue
 | |
| 
 | |
|         old_state_event_ids = set(state.values())
 | |
|         if new_state_event_ids == old_state_event_ids:
 | |
|             # got an exact match.
 | |
|             return _StateCacheEntry(state=None, state_group=sg)
 | |
| 
 | |
|     # TODO: We want to create a state group for this set of events, to
 | |
|     # increase cache hits, but we need to make sure that it doesn't
 | |
|     # end up as a prev_group without being added to the database
 | |
| 
 | |
|     # failing that, look for the closest match.
 | |
|     prev_group = None
 | |
|     delta_ids: Optional[StateMap[str]] = None
 | |
| 
 | |
|     for old_group, old_state in state_groups_ids.items():
 | |
|         if old_state.keys() - new_state.keys():
 | |
|             # Currently we don't support deltas that remove keys from the state
 | |
|             # map, so we have to ignore this group as a candidate to base the
 | |
|             # new group on.
 | |
|             continue
 | |
| 
 | |
|         n_delta_ids = {k: v for k, v in new_state.items() if old_state.get(k) != v}
 | |
|         if not delta_ids or len(n_delta_ids) < len(delta_ids):
 | |
|             prev_group = old_group
 | |
|             delta_ids = n_delta_ids
 | |
| 
 | |
|     if prev_group is not None:
 | |
|         # If we have a prev group and deltas then we can drop the new state from
 | |
|         # the cache (to reduce memory usage).
 | |
|         return _StateCacheEntry(
 | |
|             state=None, state_group=None, prev_group=prev_group, delta_ids=delta_ids
 | |
|         )
 | |
|     else:
 | |
|         return _StateCacheEntry(state=new_state, state_group=None)
 | |
| 
 | |
| 
 | |
| @attr.s(slots=True, auto_attribs=True)
 | |
| class StateResolutionStore:
 | |
|     """Interface that allows state resolution algorithms to access the database
 | |
|     in well defined way.
 | |
|     """
 | |
| 
 | |
|     store: "DataStore"
 | |
| 
 | |
|     def get_events(
 | |
|         self, event_ids: Collection[str], allow_rejected: bool = False
 | |
|     ) -> Awaitable[Dict[str, EventBase]]:
 | |
|         """Get events from the database
 | |
| 
 | |
|         Args:
 | |
|             event_ids: The event_ids of the events to fetch
 | |
|             allow_rejected: If True return rejected events.
 | |
| 
 | |
|         Returns:
 | |
|             An awaitable which resolves to a dict from event_id to event.
 | |
|         """
 | |
| 
 | |
|         return self.store.get_events(
 | |
|             event_ids,
 | |
|             redact_behaviour=EventRedactBehaviour.as_is,
 | |
|             get_prev_content=False,
 | |
|             allow_rejected=allow_rejected,
 | |
|         )
 | |
| 
 | |
|     def get_auth_chain_difference(
 | |
|         self, room_id: str, state_sets: List[Set[str]]
 | |
|     ) -> Awaitable[Set[str]]:
 | |
|         """Given sets of state events figure out the auth chain difference (as
 | |
|         per state res v2 algorithm).
 | |
| 
 | |
|         This equivalent to fetching the full auth chain for each set of state
 | |
|         and returning the events that don't appear in each and every auth
 | |
|         chain.
 | |
| 
 | |
|         Returns:
 | |
|             An awaitable that resolves to a set of event IDs.
 | |
|         """
 | |
| 
 | |
|         return self.store.get_auth_chain_difference(room_id, state_sets)
 |