diff --git a/changelog.d/10883.misc b/changelog.d/10883.misc
new file mode 100644
index 0000000000..9a765435db
--- /dev/null
+++ b/changelog.d/10883.misc
@@ -0,0 +1 @@
+Clean up some of the federation event authentication code for clarity.
diff --git a/synapse/events/snapshot.py b/synapse/events/snapshot.py
index f8d898c3b1..5ba01eeef9 100644
--- a/synapse/events/snapshot.py
+++ b/synapse/events/snapshot.py
@@ -80,9 +80,7 @@ class EventContext:
(type, state_key) -> event_id
- FIXME: what is this for an outlier? it seems ill-defined. It seems like
- it could be either {}, or the state we were given by the remote
- server, depending on $THINGS
+ 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
@@ -96,7 +94,7 @@ class EventContext:
(type, state_key) -> event_id
- FIXME: again, what is this for an outlier?
+ For an outlier, this is {}
As with _current_state_ids, this is a private attribute. It should be
accessed via get_prev_state_ids.
@@ -130,6 +128,14 @@ class EventContext:
delta_ids=delta_ids,
)
+ @staticmethod
+ def for_outlier():
+ """Return an EventContext instance suitable for persisting an outlier event"""
+ return EventContext(
+ current_state_ids={},
+ prev_state_ids={},
+ )
+
async def serialize(self, event: EventBase, store: "DataStore") -> dict:
"""Converts self to a type that can be serialized as JSON, and then
deserialized by `deserialize`
diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py
index a03d77dffd..0befe9ce43 100644
--- a/synapse/handlers/federation.py
+++ b/synapse/handlers/federation.py
@@ -624,7 +624,7 @@ class FederationHandler(BaseHandler):
# in the invitee's sync stream. It is stripped out for all other local users.
event.unsigned["knock_room_state"] = stripped_room_state["knock_state_events"]
- context = await self.state_handler.compute_event_context(event)
+ context = EventContext.for_outlier()
stream_id = await self._federation_event_handler.persist_events_and_notify(
event.room_id, [(event, context)]
)
@@ -814,7 +814,7 @@ class FederationHandler(BaseHandler):
)
)
- context = await self.state_handler.compute_event_context(event)
+ context = EventContext.for_outlier()
await self._federation_event_handler.persist_events_and_notify(
event.room_id, [(event, context)]
)
@@ -843,7 +843,7 @@ class FederationHandler(BaseHandler):
await self.federation_client.send_leave(host_list, event)
- context = await self.state_handler.compute_event_context(event)
+ context = EventContext.for_outlier()
stream_id = await self._federation_event_handler.persist_events_and_notify(
event.room_id, [(event, context)]
)
@@ -1115,8 +1115,7 @@ class FederationHandler(BaseHandler):
events_to_context = {}
for e in itertools.chain(auth_events, state):
e.internal_metadata.outlier = True
- ctx = await self.state_handler.compute_event_context(e)
- events_to_context[e.event_id] = ctx
+ events_to_context[e.event_id] = EventContext.for_outlier()
event_map = {
e.event_id: e for e in itertools.chain(auth_events, state, [event])
diff --git a/synapse/handlers/federation_event.py b/synapse/handlers/federation_event.py
index 3b95beeb08..10b3fdc222 100644
--- a/synapse/handlers/federation_event.py
+++ b/synapse/handlers/federation_event.py
@@ -1221,7 +1221,7 @@ class FederationEventHandler:
async def prep(ev_info: _NewEventInfo) -> EventContext:
event = ev_info.event
with nested_logging_context(suffix=event.event_id):
- res = await self._state_handler.compute_event_context(event)
+ res = EventContext.for_outlier()
res = await self._check_event_auth(
origin,
event,
@@ -1540,10 +1540,7 @@ class FederationEventHandler:
event.event_id,
auth_event.event_id,
)
- missing_auth_event_context = (
- await self._state_handler.compute_event_context(auth_event)
- )
-
+ missing_auth_event_context = EventContext.for_outlier()
missing_auth_event_context = await self._check_event_auth(
origin,
auth_event,
diff --git a/synapse/state/__init__.py b/synapse/state/__init__.py
index 463ce58dae..c981df3f18 100644
--- a/synapse/state/__init__.py
+++ b/synapse/state/__init__.py
@@ -263,7 +263,9 @@ class StateHandler:
async def compute_event_context(
self, event: EventBase, old_state: Optional[Iterable[EventBase]] = None
) -> EventContext:
- """Build an EventContext structure for the event.
+ """Build an EventContext structure for a non-outlier event.
+
+ (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.
@@ -278,35 +280,7 @@ class StateHandler:
The event context.
"""
- if event.internal_metadata.is_outlier():
- # If this is an outlier, then we know it shouldn't have any current
- # state. Certainly store.get_current_state won't return any, and
- # persisting the event won't store the state group.
-
- # FIXME: why do we populate current_state_ids? I thought the point was
- # that we weren't supposed to have any state for outliers?
- if old_state:
- prev_state_ids = {(s.type, s.state_key): s.event_id for s in old_state}
- if event.is_state():
- current_state_ids = dict(prev_state_ids)
- key = (event.type, event.state_key)
- current_state_ids[key] = event.event_id
- else:
- current_state_ids = prev_state_ids
- else:
- current_state_ids = {}
- prev_state_ids = {}
-
- # We don't store state for outliers, so we don't generate a state
- # group for it.
- context = EventContext.with_state(
- state_group=None,
- state_group_before_event=None,
- current_state_ids=current_state_ids,
- prev_state_ids=prev_state_ids,
- )
-
- return context
+ assert not event.internal_metadata.is_outlier()
#
# first of all, figure out the state before the event
|
