forked from MirrorHub/synapse
Refactor _resolve_state_at_missing_prevs
to return an EventContext
(#13404)
Previously, `_resolve_state_at_missing_prevs` returned the resolved state before an event and a partial state flag. These were unwieldy to carry around would only ever be used to build an event context. Build the event context directly instead. Signed-off-by: Sean Quah <seanq@matrix.org>
This commit is contained in:
parent
05aeeb3a80
commit
224d792dd7
5 changed files with 68 additions and 86 deletions
1
changelog.d/13404.misc
Normal file
1
changelog.d/13404.misc
Normal file
|
@ -0,0 +1 @@
|
|||
Refactor `_resolve_state_at_missing_prevs` to compute an `EventContext` instead.
|
|
@ -23,7 +23,6 @@ from typing import (
|
|||
Dict,
|
||||
Iterable,
|
||||
List,
|
||||
Optional,
|
||||
Sequence,
|
||||
Set,
|
||||
Tuple,
|
||||
|
@ -278,9 +277,8 @@ class FederationEventHandler:
|
|||
)
|
||||
|
||||
try:
|
||||
await self._process_received_pdu(
|
||||
origin, pdu, state_ids=None, partial_state=None
|
||||
)
|
||||
context = await self._state_handler.compute_event_context(pdu)
|
||||
await self._process_received_pdu(origin, pdu, context)
|
||||
except PartialStateConflictError:
|
||||
# The room was un-partial stated while we were processing the PDU.
|
||||
# Try once more, with full state this time.
|
||||
|
@ -288,9 +286,8 @@ class FederationEventHandler:
|
|||
"Room %s was un-partial stated while processing the PDU, trying again.",
|
||||
room_id,
|
||||
)
|
||||
await self._process_received_pdu(
|
||||
origin, pdu, state_ids=None, partial_state=None
|
||||
)
|
||||
context = await self._state_handler.compute_event_context(pdu)
|
||||
await self._process_received_pdu(origin, pdu, context)
|
||||
|
||||
async def on_send_membership_event(
|
||||
self, origin: str, event: EventBase
|
||||
|
@ -320,6 +317,7 @@ class FederationEventHandler:
|
|||
The event and context of the event after inserting it into the room graph.
|
||||
|
||||
Raises:
|
||||
RuntimeError if any prev_events are missing
|
||||
SynapseError if the event is not accepted into the room
|
||||
PartialStateConflictError if the room was un-partial stated in between
|
||||
computing the state at the event and persisting it. The caller should
|
||||
|
@ -380,7 +378,7 @@ class FederationEventHandler:
|
|||
# need to.
|
||||
await self._event_creation_handler.cache_joined_hosts_for_event(event, context)
|
||||
|
||||
await self._check_for_soft_fail(event, None, origin=origin)
|
||||
await self._check_for_soft_fail(event, context=context, origin=origin)
|
||||
await self._run_push_actions_and_persist_event(event, context)
|
||||
return event, context
|
||||
|
||||
|
@ -538,36 +536,10 @@ class FederationEventHandler:
|
|||
#
|
||||
# This is the same operation as we do when we receive a regular event
|
||||
# over federation.
|
||||
state_ids, partial_state = await self._resolve_state_at_missing_prevs(
|
||||
context = await self._compute_event_context_with_maybe_missing_prevs(
|
||||
destination, event
|
||||
)
|
||||
|
||||
# There are three possible cases for (state_ids, partial_state):
|
||||
# * `state_ids` and `partial_state` are both `None` if we had all the
|
||||
# prev_events. The prev_events may or may not have partial state and
|
||||
# we won't know until we compute the event context.
|
||||
# * `state_ids` is not `None` and `partial_state` is `False` if we were
|
||||
# missing some prev_events (but we have full state for any we did
|
||||
# have). We calculated the full state after the prev_events.
|
||||
# * `state_ids` is not `None` and `partial_state` is `True` if we were
|
||||
# missing some, but not all, prev_events. At least one of the
|
||||
# prev_events we did have had partial state, so we calculated a partial
|
||||
# state after the prev_events.
|
||||
|
||||
context = None
|
||||
if state_ids is not None and partial_state:
|
||||
# the state after the prev events is still partial. We can't de-partial
|
||||
# state the event, so don't bother building the event context.
|
||||
pass
|
||||
else:
|
||||
# build a new state group for it if need be
|
||||
context = await self._state_handler.compute_event_context(
|
||||
event,
|
||||
state_ids_before_event=state_ids,
|
||||
partial_state=partial_state,
|
||||
)
|
||||
|
||||
if context is None or context.partial_state:
|
||||
if context.partial_state:
|
||||
# this can happen if some or all of the event's prev_events still have
|
||||
# partial state. We were careful to only pick events from the db without
|
||||
# partial-state prev events, so that implies that a prev event has
|
||||
|
@ -840,26 +812,25 @@ class FederationEventHandler:
|
|||
|
||||
try:
|
||||
try:
|
||||
state_ids, partial_state = await self._resolve_state_at_missing_prevs(
|
||||
context = await self._compute_event_context_with_maybe_missing_prevs(
|
||||
origin, event
|
||||
)
|
||||
await self._process_received_pdu(
|
||||
origin,
|
||||
event,
|
||||
state_ids=state_ids,
|
||||
partial_state=partial_state,
|
||||
context,
|
||||
backfilled=backfilled,
|
||||
)
|
||||
except PartialStateConflictError:
|
||||
# The room was un-partial stated while we were processing the event.
|
||||
# Try once more, with full state this time.
|
||||
state_ids, partial_state = await self._resolve_state_at_missing_prevs(
|
||||
context = await self._compute_event_context_with_maybe_missing_prevs(
|
||||
origin, event
|
||||
)
|
||||
|
||||
# We ought to have full state now, barring some unlikely race where we left and
|
||||
# rejoned the room in the background.
|
||||
if state_ids is not None and partial_state:
|
||||
if context.partial_state:
|
||||
raise AssertionError(
|
||||
f"Event {event.event_id} still has a partial resolved state "
|
||||
f"after room {event.room_id} was un-partial stated"
|
||||
|
@ -868,8 +839,7 @@ class FederationEventHandler:
|
|||
await self._process_received_pdu(
|
||||
origin,
|
||||
event,
|
||||
state_ids=state_ids,
|
||||
partial_state=partial_state,
|
||||
context,
|
||||
backfilled=backfilled,
|
||||
)
|
||||
except FederationError as e:
|
||||
|
@ -878,15 +848,18 @@ class FederationEventHandler:
|
|||
else:
|
||||
raise
|
||||
|
||||
async def _resolve_state_at_missing_prevs(
|
||||
async def _compute_event_context_with_maybe_missing_prevs(
|
||||
self, dest: str, event: EventBase
|
||||
) -> Tuple[Optional[StateMap[str]], Optional[bool]]:
|
||||
"""Calculate the state at an event with missing prev_events.
|
||||
) -> EventContext:
|
||||
"""Build an EventContext structure for a non-outlier event whose prev_events may
|
||||
be missing.
|
||||
|
||||
This is used when we have pulled a batch of events from a remote server, and
|
||||
still don't have all the prev_events.
|
||||
This is used when we have pulled a batch of events from a remote server, and may
|
||||
not have all the prev_events.
|
||||
|
||||
If we already have all the prev_events for `event`, this method does nothing.
|
||||
To build an EventContext, we need to calculate the state before the event. If we
|
||||
already have all the prev_events for `event`, we can simply use the state after
|
||||
the prev_events to calculate the state before `event`.
|
||||
|
||||
Otherwise, the missing prevs become new backwards extremities, and we fall back
|
||||
to asking the remote server for the state after each missing `prev_event`,
|
||||
|
@ -907,10 +880,7 @@ class FederationEventHandler:
|
|||
event: an event to check for missing prevs.
|
||||
|
||||
Returns:
|
||||
if we already had all the prev events, `None, None`. Otherwise, returns a
|
||||
tuple containing:
|
||||
* the event ids of the state at `event`.
|
||||
* a boolean indicating whether the state may be partial.
|
||||
The event context.
|
||||
|
||||
Raises:
|
||||
FederationError if we fail to get the state from the remote server after any
|
||||
|
@ -924,7 +894,7 @@ class FederationEventHandler:
|
|||
missing_prevs = prevs - seen
|
||||
|
||||
if not missing_prevs:
|
||||
return None, None
|
||||
return await self._state_handler.compute_event_context(event)
|
||||
|
||||
logger.info(
|
||||
"Event %s is missing prev_events %s: calculating state for a "
|
||||
|
@ -990,7 +960,9 @@ class FederationEventHandler:
|
|||
"We can't get valid state history.",
|
||||
affected=event_id,
|
||||
)
|
||||
return state_map, partial_state
|
||||
return await self._state_handler.compute_event_context(
|
||||
event, state_ids_before_event=state_map, partial_state=partial_state
|
||||
)
|
||||
|
||||
async def _get_state_ids_after_missing_prev_event(
|
||||
self,
|
||||
|
@ -1159,8 +1131,7 @@ class FederationEventHandler:
|
|||
self,
|
||||
origin: str,
|
||||
event: EventBase,
|
||||
state_ids: Optional[StateMap[str]],
|
||||
partial_state: Optional[bool],
|
||||
context: EventContext,
|
||||
backfilled: bool = False,
|
||||
) -> None:
|
||||
"""Called when we have a new non-outlier event.
|
||||
|
@ -1182,32 +1153,18 @@ class FederationEventHandler:
|
|||
|
||||
event: event to be persisted
|
||||
|
||||
state_ids: Normally None, but if we are handling a gap in the graph
|
||||
(ie, we are missing one or more prev_events), the resolved state at the
|
||||
event
|
||||
|
||||
partial_state:
|
||||
`True` if `state_ids` is partial and omits non-critical membership
|
||||
events.
|
||||
`False` if `state_ids` is the full state.
|
||||
`None` if `state_ids` is not provided. In this case, the flag will be
|
||||
calculated based on `event`'s prev events.
|
||||
context: The `EventContext` to persist the event with.
|
||||
|
||||
backfilled: True if this is part of a historical batch of events (inhibits
|
||||
notification to clients, and validation of device keys.)
|
||||
|
||||
PartialStateConflictError: if the room was un-partial stated in between
|
||||
computing the state at the event and persisting it. The caller should retry
|
||||
exactly once in this case.
|
||||
computing the state at the event and persisting it. The caller should
|
||||
recompute `context` and retry exactly once when this happens.
|
||||
"""
|
||||
logger.debug("Processing event: %s", event)
|
||||
assert not event.internal_metadata.outlier
|
||||
|
||||
context = await self._state_handler.compute_event_context(
|
||||
event,
|
||||
state_ids_before_event=state_ids,
|
||||
partial_state=partial_state,
|
||||
)
|
||||
try:
|
||||
await self._check_event_auth(origin, event, context)
|
||||
except AuthError as e:
|
||||
|
@ -1219,7 +1176,7 @@ class FederationEventHandler:
|
|||
# For new (non-backfilled and non-outlier) events we check if the event
|
||||
# passes auth based on the current state. If it doesn't then we
|
||||
# "soft-fail" the event.
|
||||
await self._check_for_soft_fail(event, state_ids, origin=origin)
|
||||
await self._check_for_soft_fail(event, context=context, origin=origin)
|
||||
|
||||
await self._run_push_actions_and_persist_event(event, context, backfilled)
|
||||
|
||||
|
@ -1782,7 +1739,7 @@ class FederationEventHandler:
|
|||
async def _check_for_soft_fail(
|
||||
self,
|
||||
event: EventBase,
|
||||
state_ids: Optional[StateMap[str]],
|
||||
context: EventContext,
|
||||
origin: str,
|
||||
) -> None:
|
||||
"""Checks if we should soft fail the event; if so, marks the event as
|
||||
|
@ -1793,7 +1750,7 @@ class FederationEventHandler:
|
|||
|
||||
Args:
|
||||
event
|
||||
state_ids: The state at the event if we don't have all the event's prev events
|
||||
context: The `EventContext` which we are about to persist the event with.
|
||||
origin: The host the event originates from.
|
||||
"""
|
||||
if await self._store.is_partial_state_room(event.room_id):
|
||||
|
@ -1819,11 +1776,15 @@ class FederationEventHandler:
|
|||
auth_types = auth_types_for_event(room_version_obj, event)
|
||||
|
||||
# Calculate the "current state".
|
||||
if state_ids is not None:
|
||||
# If we're explicitly given the state then we won't have all the
|
||||
# prev events, and so we have a gap in the graph. In this case
|
||||
# we want to be a little careful as we might have been down for
|
||||
# a while and have an incorrect view of the current state,
|
||||
seen_event_ids = await self._store.have_events_in_timeline(prev_event_ids)
|
||||
has_missing_prevs = bool(prev_event_ids - seen_event_ids)
|
||||
if has_missing_prevs:
|
||||
# We don't have all the prev_events of this event, which means we have a
|
||||
# gap in the graph, and the new event is going to become a new backwards
|
||||
# extremity.
|
||||
#
|
||||
# In this case we want to be a little careful as we might have been
|
||||
# down for a while and have an incorrect view of the current state,
|
||||
# however we still want to do checks as gaps are easy to
|
||||
# maliciously manufacture.
|
||||
#
|
||||
|
@ -1836,6 +1797,7 @@ class FederationEventHandler:
|
|||
event.room_id, extrem_ids
|
||||
)
|
||||
state_sets: List[StateMap[str]] = list(state_sets_d.values())
|
||||
state_ids = await context.get_prev_state_ids()
|
||||
state_sets.append(state_ids)
|
||||
current_state_ids = (
|
||||
await self._state_resolution_handler.resolve_events_with_store(
|
||||
|
|
|
@ -278,6 +278,10 @@ class StateHandler:
|
|||
flag will be calculated based on `event`'s prev events.
|
||||
Returns:
|
||||
The event context.
|
||||
|
||||
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()
|
||||
|
@ -432,6 +436,10 @@ class StateHandler:
|
|||
|
||||
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)
|
||||
|
||||
|
|
|
@ -338,6 +338,10 @@ class StateStorageController:
|
|||
event_ids: events to get state groups for
|
||||
await_full_state: if true, will block if we do not yet have complete
|
||||
state at these events.
|
||||
|
||||
Raises:
|
||||
RuntimeError if we don't have a state group for one or more of the events
|
||||
(ie. they are outliers or unknown)
|
||||
"""
|
||||
if await_full_state:
|
||||
await self._partial_state_events_tracker.await_full_state(event_ids)
|
||||
|
|
|
@ -280,14 +280,21 @@ class FederationTestCase(unittest.FederatingHomeserverTestCase):
|
|||
|
||||
# we poke this directly into _process_received_pdu, to avoid the
|
||||
# federation handler wanting to backfill the fake event.
|
||||
state_handler = self.hs.get_state_handler()
|
||||
context = self.get_success(
|
||||
state_handler.compute_event_context(
|
||||
event,
|
||||
state_ids_before_event={
|
||||
(e.type, e.state_key): e.event_id for e in current_state
|
||||
},
|
||||
partial_state=False,
|
||||
)
|
||||
)
|
||||
self.get_success(
|
||||
federation_event_handler._process_received_pdu(
|
||||
self.OTHER_SERVER_NAME,
|
||||
event,
|
||||
state_ids={
|
||||
(e.type, e.state_key): e.event_id for e in current_state
|
||||
},
|
||||
partial_state=False,
|
||||
context,
|
||||
)
|
||||
)
|
||||
|
||||
|
|
Loading…
Reference in a new issue