diff --git a/synapse/events/snapshot.py b/synapse/events/snapshot.py
index 8120c305df..9ccd24b298 100644
--- a/synapse/events/snapshot.py
+++ b/synapse/events/snapshot.py
@@ -17,11 +17,8 @@ import attr
from frozendict import frozendict
from typing_extensions import Literal
-from twisted.internet.defer import Deferred
-
from synapse.appservice import ApplicationService
from synapse.events import EventBase
-from synapse.logging.context import make_deferred_yieldable, run_in_background
from synapse.types import JsonDict, StateMap
if TYPE_CHECKING:
@@ -61,6 +58,9 @@ class EventContext:
If ``state_group`` is None (ie, the event is an outlier),
``state_group_before_event`` will always also be ``None``.
+ state_delta_due_to_event: If `state_group` and `state_group_before_event` are not None
+ then this is the delta of the state between the two groups.
+
prev_group: If it is known, ``state_group``'s prev_group. Note that this being
None does not necessarily mean that ``state_group`` does not have
a prev_group!
@@ -79,73 +79,47 @@ class EventContext:
app_service: If this event is being sent by a (local) application service, that
app service.
- _current_state_ids: The room state map, including this event - ie, the state
- in ``state_group``.
-
- (type, state_key) -> event_id
-
- For an outlier, this is {}
-
- Note that this is a private attribute: it should be accessed via
- ``get_current_state_ids``. _AsyncEventContext impl calculates this
- on-demand: it will be None until that happens.
-
- _prev_state_ids: The room state map, excluding this event - ie, the state
- in ``state_group_before_event``. For a non-state
- event, this will be the same as _current_state_events.
-
- Note that it is a completely different thing to prev_group!
-
- (type, state_key) -> event_id
-
- For an outlier, this is {}
-
- As with _current_state_ids, this is a private attribute. It should be
- accessed via get_prev_state_ids.
-
partial_state: if True, we may be storing this event with a temporary,
incomplete state.
"""
+ _storage: "Storage"
rejected: Union[Literal[False], str] = False
_state_group: Optional[int] = None
state_group_before_event: Optional[int] = None
+ _state_delta_due_to_event: Optional[StateMap[str]] = None
prev_group: Optional[int] = None
delta_ids: Optional[StateMap[str]] = None
app_service: Optional[ApplicationService] = None
- _current_state_ids: Optional[StateMap[str]] = None
- _prev_state_ids: Optional[StateMap[str]] = None
-
partial_state: bool = False
@staticmethod
def with_state(
+ storage: "Storage",
state_group: Optional[int],
state_group_before_event: Optional[int],
- current_state_ids: Optional[StateMap[str]],
- prev_state_ids: Optional[StateMap[str]],
+ state_delta_due_to_event: Optional[StateMap[str]],
partial_state: bool,
prev_group: Optional[int] = None,
delta_ids: Optional[StateMap[str]] = None,
) -> "EventContext":
return EventContext(
- current_state_ids=current_state_ids,
- prev_state_ids=prev_state_ids,
+ storage=storage,
state_group=state_group,
state_group_before_event=state_group_before_event,
+ state_delta_due_to_event=state_delta_due_to_event,
prev_group=prev_group,
delta_ids=delta_ids,
partial_state=partial_state,
)
@staticmethod
- def for_outlier() -> "EventContext":
+ def for_outlier(
+ storage: "Storage",
+ ) -> "EventContext":
"""Return an EventContext instance suitable for persisting an outlier event"""
- return EventContext(
- current_state_ids={},
- prev_state_ids={},
- )
+ return EventContext(storage=storage)
async def serialize(self, event: EventBase, store: "DataStore") -> JsonDict:
"""Converts self to a type that can be serialized as JSON, and then
@@ -158,24 +132,14 @@ class EventContext:
The serialized event.
"""
- # We don't serialize the full state dicts, instead they get pulled out
- # of the DB on the other side. However, the other side can't figure out
- # the prev_state_ids, so if we're a state event we include the event
- # id that we replaced in the state.
- if event.is_state():
- prev_state_ids = await self.get_prev_state_ids()
- prev_state_id = prev_state_ids.get((event.type, event.state_key))
- else:
- prev_state_id = None
-
return {
- "prev_state_id": prev_state_id,
- "event_type": event.type,
- "event_state_key": event.get_state_key(),
"state_group": self._state_group,
"state_group_before_event": self.state_group_before_event,
"rejected": self.rejected,
"prev_group": self.prev_group,
+ "state_delta_due_to_event": _encode_state_dict(
+ self._state_delta_due_to_event
+ ),
"delta_ids": _encode_state_dict(self.delta_ids),
"app_service_id": self.app_service.id if self.app_service else None,
"partial_state": self.partial_state,
@@ -193,16 +157,16 @@ class EventContext:
Returns:
The event context.
"""
- context = _AsyncEventContextImpl(
+ context = EventContext(
# We use the state_group and prev_state_id stuff to pull the
# current_state_ids out of the DB and construct prev_state_ids.
storage=storage,
- prev_state_id=input["prev_state_id"],
- event_type=input["event_type"],
- event_state_key=input["event_state_key"],
state_group=input["state_group"],
state_group_before_event=input["state_group_before_event"],
prev_group=input["prev_group"],
+ state_delta_due_to_event=_decode_state_dict(
+ input["state_delta_due_to_event"]
+ ),
delta_ids=_decode_state_dict(input["delta_ids"]),
rejected=input["rejected"],
partial_state=input.get("partial_state", False),
@@ -250,8 +214,15 @@ class EventContext:
if self.rejected:
raise RuntimeError("Attempt to access state_ids of rejected event")
- await self._ensure_fetched()
- return self._current_state_ids
+ assert self._state_delta_due_to_event is not None
+
+ prev_state_ids = await self.get_prev_state_ids()
+
+ if self._state_delta_due_to_event:
+ prev_state_ids = dict(prev_state_ids)
+ prev_state_ids.update(self._state_delta_due_to_event)
+
+ return prev_state_ids
async def get_prev_state_ids(self) -> StateMap[str]:
"""
@@ -266,94 +237,10 @@ class EventContext:
Maps a (type, state_key) to the event ID of the state event matching
this tuple.
"""
- await self._ensure_fetched()
- # There *should* be previous state IDs now.
- assert self._prev_state_ids is not None
- return self._prev_state_ids
-
- def get_cached_current_state_ids(self) -> Optional[StateMap[str]]:
- """Gets the current state IDs if we have them already cached.
-
- It is an error to access this for a rejected event, since rejected state should
- not make it into the room state. This method will raise an exception if
- ``rejected`` is set.
-
- Returns:
- Returns None if we haven't cached the state or if state_group is None
- (which happens when the associated event is an outlier).
-
- Otherwise, returns the the current state IDs.
- """
- if self.rejected:
- raise RuntimeError("Attempt to access state_ids of rejected event")
-
- return self._current_state_ids
-
- async def _ensure_fetched(self) -> None:
- return None
-
-
-@attr.s(slots=True)
-class _AsyncEventContextImpl(EventContext):
- """
- An implementation of EventContext which fetches _current_state_ids and
- _prev_state_ids from the database on demand.
-
- Attributes:
-
- _storage
-
- _fetching_state_deferred: Resolves when *_state_ids have been calculated.
- None if we haven't started calculating yet
-
- _event_type: The type of the event the context is associated with.
-
- _event_state_key: The state_key of the event the context is associated with.
-
- _prev_state_id: If the event associated with the context is a state event,
- then `_prev_state_id` is the event_id of the state that was replaced.
- """
-
- # This needs to have a default as we're inheriting
- _storage: "Storage" = attr.ib(default=None)
- _prev_state_id: Optional[str] = attr.ib(default=None)
- _event_type: str = attr.ib(default=None)
- _event_state_key: Optional[str] = attr.ib(default=None)
- _fetching_state_deferred: Optional["Deferred[None]"] = attr.ib(default=None)
-
- async def _ensure_fetched(self) -> None:
- if not self._fetching_state_deferred:
- self._fetching_state_deferred = run_in_background(self._fill_out_state)
-
- await make_deferred_yieldable(self._fetching_state_deferred)
-
- async def _fill_out_state(self) -> None:
- """Called to populate the _current_state_ids and _prev_state_ids
- attributes by loading from the database.
- """
- if self.state_group is None:
- # No state group means the event is an outlier. Usually the state_ids dicts are also
- # pre-set to empty dicts, but they get reset when the context is serialized, so set
- # them to empty dicts again here.
- self._current_state_ids = {}
- self._prev_state_ids = {}
- return
-
- current_state_ids = await self._storage.state.get_state_ids_for_group(
- self.state_group
+ assert self.state_group_before_event is not None
+ return await self._storage.state.get_state_ids_for_group(
+ self.state_group_before_event
)
- # Set this separately so mypy knows current_state_ids is not None.
- self._current_state_ids = current_state_ids
- if self._event_state_key is not None:
- self._prev_state_ids = dict(current_state_ids)
-
- key = (self._event_type, self._event_state_key)
- if self._prev_state_id:
- self._prev_state_ids[key] = self._prev_state_id
- else:
- self._prev_state_ids.pop(key, None)
- else:
- self._prev_state_ids = current_state_ids
def _encode_state_dict(
|
