diff --git a/synapse/visibility.py b/synapse/visibility.py
index e442de3173..468e22f8f6 100644
--- a/synapse/visibility.py
+++ b/synapse/visibility.py
@@ -14,7 +14,17 @@
# limitations under the License.
import logging
from enum import Enum, auto
-from typing import Collection, Dict, FrozenSet, List, Optional, Tuple
+from typing import (
+ Collection,
+ Dict,
+ FrozenSet,
+ List,
+ Mapping,
+ Optional,
+ Sequence,
+ Set,
+ Tuple,
+)
import attr
from typing_extensions import Final
@@ -565,29 +575,43 @@ async def filter_events_for_server(
storage: StorageControllers,
target_server_name: str,
local_server_name: str,
- events: List[EventBase],
- redact: bool = True,
- check_history_visibility_only: bool = False,
+ events: Sequence[EventBase],
+ *,
+ redact: bool,
+ filter_out_erased_senders: bool,
+ filter_out_remote_partial_state_events: bool,
) -> List[EventBase]:
- """Filter a list of events based on whether given server is allowed to
+ """Filter a list of events based on whether the target server is allowed to
see them.
+ For a fully stated room, the target server is allowed to see an event E if:
+ - the state at E has world readable or shared history vis, OR
+ - the state at E says that the target server is in the room.
+
+ For a partially stated room, the target server is allowed to see E if:
+ - E was created by this homeserver, AND:
+ - the partial state at E has world readable or shared history vis, OR
+ - the partial state at E says that the target server is in the room.
+
+ TODO: state before or state after?
+
Args:
storage
- server_name
+ target_server_name
+ local_server_name
events
- redact: Whether to return a redacted version of the event, or
- to filter them out entirely.
- check_history_visibility_only: Whether to only check the
- history visibility, rather than things like if the sender has been
+ redact: Controls what to do with events which have been filtered out.
+ If True, include their redacted forms; if False, omit them entirely.
+ filter_out_erased_senders: If true, also filter out events whose sender has been
erased. This is used e.g. during pagination to decide whether to
backfill or not.
-
+ filter_out_remote_partial_state_events: If True, also filter out events in
+ partial state rooms created by other homeservers.
Returns
The filtered events.
"""
- def is_sender_erased(event: EventBase, erased_senders: Dict[str, bool]) -> bool:
+ def is_sender_erased(event: EventBase, erased_senders: Mapping[str, bool]) -> bool:
if erased_senders and erased_senders[event.sender]:
logger.info("Sender of %s has been erased, redacting", event.event_id)
return True
@@ -616,7 +640,7 @@ async def filter_events_for_server(
# server has no users in the room: redact
return False
- if not check_history_visibility_only:
+ if filter_out_erased_senders:
erased_senders = await storage.main.are_users_erased(e.sender for e in events)
else:
# We don't want to check whether users are erased, which is equivalent
@@ -631,15 +655,15 @@ async def filter_events_for_server(
# otherwise a room could be fully joined after we retrieve those, which would then bypass
# this check but would base the filtering on an outdated view of the membership events.
- partial_state_invisible_events = set()
- if not check_history_visibility_only:
+ partial_state_invisible_event_ids: Set[str] = set()
+ if filter_out_remote_partial_state_events:
for e in events:
sender_domain = get_domain_from_id(e.sender)
if (
sender_domain != local_server_name
and await storage.main.is_partial_state_room(e.room_id)
):
- partial_state_invisible_events.add(e)
+ partial_state_invisible_event_ids.add(e.event_id)
# Let's check to see if all the events have a history visibility
# of "shared" or "world_readable". If that's the case then we don't
@@ -658,17 +682,20 @@ async def filter_events_for_server(
target_server_name,
)
- to_return = []
- for e in events:
+ def include_event_in_output(e: EventBase) -> bool:
erased = is_sender_erased(e, erased_senders)
visible = check_event_is_visible(
event_to_history_vis[e.event_id], event_to_memberships.get(e.event_id, {})
)
- if e in partial_state_invisible_events:
+ if e.event_id in partial_state_invisible_event_ids:
visible = False
- if visible and not erased:
+ return visible and not erased
+
+ to_return = []
+ for e in events:
+ if include_event_in_output(e):
to_return.append(e)
elif redact:
to_return.append(prune_event(e))
|
