1183 lines
		
	
	
		
			44 KiB
		
	
	
	
		
			Python
		
	
	
			
		
		
	
	
			1183 lines
		
	
	
		
			44 KiB
		
	
	
	
		
			Python
		
	
	
| # Copyright 2021 The Matrix.org Foundation C.I.C.
 | ||
| #
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| # Licensed under the Apache License, Version 2.0 (the "License");
 | ||
| # you may not use this file except in compliance with the License.
 | ||
| # You may obtain a copy of the License at
 | ||
| #
 | ||
| #     http://www.apache.org/licenses/LICENSE-2.0
 | ||
| #
 | ||
| # Unless required by applicable law or agreed to in writing, software
 | ||
| # distributed under the License is distributed on an "AS IS" BASIS,
 | ||
| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 | ||
| # See the License for the specific language governing permissions and
 | ||
| # limitations under the License.
 | ||
| 
 | ||
| import itertools
 | ||
| import logging
 | ||
| import re
 | ||
| from collections import deque
 | ||
| from typing import TYPE_CHECKING, Dict, Iterable, List, Optional, Sequence, Set, Tuple
 | ||
| 
 | ||
| import attr
 | ||
| 
 | ||
| from synapse.api.constants import (
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|     EventContentFields,
 | ||
|     EventTypes,
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|     HistoryVisibility,
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|     JoinRules,
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|     Membership,
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|     RoomTypes,
 | ||
| )
 | ||
| from synapse.api.errors import (
 | ||
|     AuthError,
 | ||
|     Codes,
 | ||
|     NotFoundError,
 | ||
|     StoreError,
 | ||
|     SynapseError,
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|     UnsupportedRoomVersionError,
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| )
 | ||
| from synapse.events import EventBase
 | ||
| from synapse.types import JsonDict
 | ||
| from synapse.util.caches.response_cache import ResponseCache
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| 
 | ||
| if TYPE_CHECKING:
 | ||
|     from synapse.server import HomeServer
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| 
 | ||
| logger = logging.getLogger(__name__)
 | ||
| 
 | ||
| # number of rooms to return. We'll stop once we hit this limit.
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| MAX_ROOMS = 50
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| 
 | ||
| # max number of events to return per room.
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| MAX_ROOMS_PER_SPACE = 50
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| 
 | ||
| # max number of federation servers to hit per room
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| MAX_SERVERS_PER_SPACE = 3
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| 
 | ||
| 
 | ||
| @attr.s(slots=True, frozen=True, auto_attribs=True)
 | ||
| class _PaginationKey:
 | ||
|     """The key used to find unique pagination session."""
 | ||
| 
 | ||
|     # The first three entries match the request parameters (and cannot change
 | ||
|     # during a pagination session).
 | ||
|     room_id: str
 | ||
|     suggested_only: bool
 | ||
|     max_depth: Optional[int]
 | ||
|     # The randomly generated token.
 | ||
|     token: str
 | ||
| 
 | ||
| 
 | ||
| @attr.s(slots=True, frozen=True, auto_attribs=True)
 | ||
| class _PaginationSession:
 | ||
|     """The information that is stored for pagination."""
 | ||
| 
 | ||
|     # The time the pagination session was created, in milliseconds.
 | ||
|     creation_time_ms: int
 | ||
|     # The queue of rooms which are still to process.
 | ||
|     room_queue: List["_RoomQueueEntry"]
 | ||
|     # A set of rooms which have been processed.
 | ||
|     processed_rooms: Set[str]
 | ||
| 
 | ||
| 
 | ||
| class RoomSummaryHandler:
 | ||
|     # A unique key used for pagination sessions for the room hierarchy endpoint.
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|     _PAGINATION_SESSION_TYPE = "room_hierarchy_pagination"
 | ||
| 
 | ||
|     # The time a pagination session remains valid for.
 | ||
|     _PAGINATION_SESSION_VALIDITY_PERIOD_MS = 5 * 60 * 1000
 | ||
| 
 | ||
|     def __init__(self, hs: "HomeServer"):
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|         self._event_auth_handler = hs.get_event_auth_handler()
 | ||
|         self._store = hs.get_datastore()
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|         self._event_serializer = hs.get_event_client_serializer()
 | ||
|         self._server_name = hs.hostname
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|         self._federation_client = hs.get_federation_client()
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| 
 | ||
|         # If a user tries to fetch the same page multiple times in quick succession,
 | ||
|         # only process the first attempt and return its result to subsequent requests.
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|         self._pagination_response_cache: ResponseCache[
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|             Tuple[str, bool, Optional[int], Optional[int], Optional[str]]
 | ||
|         ] = ResponseCache(
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|             hs.get_clock(),
 | ||
|             "get_room_hierarchy",
 | ||
|         )
 | ||
| 
 | ||
|     async def get_space_summary(
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|         self,
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|         requester: str,
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|         room_id: str,
 | ||
|         suggested_only: bool = False,
 | ||
|         max_rooms_per_space: Optional[int] = None,
 | ||
|     ) -> JsonDict:
 | ||
|         """
 | ||
|         Implementation of the space summary C-S API
 | ||
| 
 | ||
|         Args:
 | ||
|             requester:  user id of the user making this request
 | ||
| 
 | ||
|             room_id: room id to start the summary at
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| 
 | ||
|             suggested_only: whether we should only return children with the "suggested"
 | ||
|                 flag set.
 | ||
| 
 | ||
|             max_rooms_per_space: an optional limit on the number of child rooms we will
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|                 return. This does not apply to the root room (ie, room_id), and
 | ||
|                 is overridden by MAX_ROOMS_PER_SPACE.
 | ||
| 
 | ||
|         Returns:
 | ||
|             summary dict to return
 | ||
|         """
 | ||
|         # First of all, check that the room is accessible.
 | ||
|         if not await self._is_local_room_accessible(room_id, requester):
 | ||
|             raise AuthError(
 | ||
|                 403,
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|                 "User %s not in room %s, and room previews are disabled"
 | ||
|                 % (requester, room_id),
 | ||
|             )
 | ||
| 
 | ||
|         # the queue of rooms to process
 | ||
|         room_queue = deque((_RoomQueueEntry(room_id, ()),))
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| 
 | ||
|         # rooms we have already processed
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|         processed_rooms: Set[str] = set()
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| 
 | ||
|         # events we have already processed. We don't necessarily have their event ids,
 | ||
|         # so instead we key on (room id, state key)
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|         processed_events: Set[Tuple[str, str]] = set()
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| 
 | ||
|         rooms_result: List[JsonDict] = []
 | ||
|         events_result: List[JsonDict] = []
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| 
 | ||
|         while room_queue and len(rooms_result) < MAX_ROOMS:
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|             queue_entry = room_queue.popleft()
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|             room_id = queue_entry.room_id
 | ||
|             if room_id in processed_rooms:
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|                 # already done this room
 | ||
|                 continue
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| 
 | ||
|             logger.debug("Processing room %s", room_id)
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| 
 | ||
|             is_in_room = await self._store.is_host_joined(room_id, self._server_name)
 | ||
| 
 | ||
|             # The client-specified max_rooms_per_space limit doesn't apply to the
 | ||
|             # room_id specified in the request, so we ignore it if this is the
 | ||
|             # first room we are processing.
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|             max_children = max_rooms_per_space if processed_rooms else None
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| 
 | ||
|             if is_in_room:
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|                 room_entry = await self._summarize_local_room(
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|                     requester, None, room_id, suggested_only, max_children
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|                 )
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| 
 | ||
|                 events: Sequence[JsonDict] = []
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|                 if room_entry:
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|                     rooms_result.append(room_entry.room)
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|                     events = room_entry.children_state_events
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| 
 | ||
|                 logger.debug(
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|                     "Query of local room %s returned events %s",
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|                     room_id,
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|                     ["%s->%s" % (ev["room_id"], ev["state_key"]) for ev in events],
 | ||
|                 )
 | ||
|             else:
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|                 fed_rooms = await self._summarize_remote_room(
 | ||
|                     queue_entry,
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|                     suggested_only,
 | ||
|                     max_children,
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|                     exclude_rooms=processed_rooms,
 | ||
|                 )
 | ||
| 
 | ||
|                 # The results over federation might include rooms that the we,
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|                 # as the requesting server, are allowed to see, but the requesting
 | ||
|                 # user is not permitted see.
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|                 #
 | ||
|                 # Filter the returned results to only what is accessible to the user.
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|                 events = []
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|                 for room_entry in fed_rooms:
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|                     room = room_entry.room
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|                     fed_room_id = room_entry.room_id
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| 
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|                     # The user can see the room, include it!
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|                     if await self._is_remote_room_accessible(
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|                         requester, fed_room_id, room
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|                     ):
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|                         # Before returning to the client, remove the allowed_room_ids
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|                         # and allowed_spaces keys.
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|                         room.pop("allowed_room_ids", None)
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|                         room.pop("allowed_spaces", None)
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| 
 | ||
|                         rooms_result.append(room)
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|                         events.extend(room_entry.children_state_events)
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| 
 | ||
|                     # All rooms returned don't need visiting again (even if the user
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|                     # didn't have access to them).
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|                     processed_rooms.add(fed_room_id)
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| 
 | ||
|                 logger.debug(
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|                     "Query of %s returned rooms %s, events %s",
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|                     room_id,
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|                     [room_entry.room.get("room_id") for room_entry in fed_rooms],
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|                     ["%s->%s" % (ev["room_id"], ev["state_key"]) for ev in events],
 | ||
|                 )
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| 
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|             # the room we queried may or may not have been returned, but don't process
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|             # it again, anyway.
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|             processed_rooms.add(room_id)
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| 
 | ||
|             # XXX: is it ok that we blindly iterate through any events returned by
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|             #   a remote server, whether or not they actually link to any rooms in our
 | ||
|             #   tree?
 | ||
|             for ev in events:
 | ||
|                 # remote servers might return events we have already processed
 | ||
|                 # (eg, Dendrite returns inward pointers as well as outward ones), so
 | ||
|                 # we need to filter them out, to avoid returning duplicate links to the
 | ||
|                 # client.
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|                 ev_key = (ev["room_id"], ev["state_key"])
 | ||
|                 if ev_key in processed_events:
 | ||
|                     continue
 | ||
|                 events_result.append(ev)
 | ||
| 
 | ||
|                 # add the child to the queue. we have already validated
 | ||
|                 # that the vias are a list of server names.
 | ||
|                 room_queue.append(
 | ||
|                     _RoomQueueEntry(ev["state_key"], ev["content"]["via"])
 | ||
|                 )
 | ||
|                 processed_events.add(ev_key)
 | ||
| 
 | ||
|         return {"rooms": rooms_result, "events": events_result}
 | ||
| 
 | ||
|     async def get_room_hierarchy(
 | ||
|         self,
 | ||
|         requester: str,
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|         requested_room_id: str,
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|         suggested_only: bool = False,
 | ||
|         max_depth: Optional[int] = None,
 | ||
|         limit: Optional[int] = None,
 | ||
|         from_token: Optional[str] = None,
 | ||
|     ) -> JsonDict:
 | ||
|         """
 | ||
|         Implementation of the room hierarchy C-S API.
 | ||
| 
 | ||
|         Args:
 | ||
|             requester: The user ID of the user making this request.
 | ||
|             requested_room_id: The room ID to start the hierarchy at (the "root" room).
 | ||
|             suggested_only: Whether we should only return children with the "suggested"
 | ||
|                 flag set.
 | ||
|             max_depth: The maximum depth in the tree to explore, must be a
 | ||
|                 non-negative integer.
 | ||
| 
 | ||
|                 0 would correspond to just the root room, 1 would include just
 | ||
|                 the root room's children, etc.
 | ||
|             limit: An optional limit on the number of rooms to return per
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|                 page. Must be a positive integer.
 | ||
|             from_token: An optional pagination token.
 | ||
| 
 | ||
|         Returns:
 | ||
|             The JSON hierarchy dictionary.
 | ||
|         """
 | ||
|         # If a user tries to fetch the same page multiple times in quick succession,
 | ||
|         # only process the first attempt and return its result to subsequent requests.
 | ||
|         #
 | ||
|         # This is due to the pagination process mutating internal state, attempting
 | ||
|         # to process multiple requests for the same page will result in errors.
 | ||
|         return await self._pagination_response_cache.wrap(
 | ||
|             (requested_room_id, suggested_only, max_depth, limit, from_token),
 | ||
|             self._get_room_hierarchy,
 | ||
|             requester,
 | ||
|             requested_room_id,
 | ||
|             suggested_only,
 | ||
|             max_depth,
 | ||
|             limit,
 | ||
|             from_token,
 | ||
|         )
 | ||
| 
 | ||
|     async def _get_room_hierarchy(
 | ||
|         self,
 | ||
|         requester: str,
 | ||
|         requested_room_id: str,
 | ||
|         suggested_only: bool = False,
 | ||
|         max_depth: Optional[int] = None,
 | ||
|         limit: Optional[int] = None,
 | ||
|         from_token: Optional[str] = None,
 | ||
|     ) -> JsonDict:
 | ||
|         """See docstring for SpaceSummaryHandler.get_room_hierarchy."""
 | ||
| 
 | ||
|         # First of all, check that the room is accessible.
 | ||
|         if not await self._is_local_room_accessible(requested_room_id, requester):
 | ||
|             raise AuthError(
 | ||
|                 403,
 | ||
|                 "User %s not in room %s, and room previews are disabled"
 | ||
|                 % (requester, requested_room_id),
 | ||
|             )
 | ||
| 
 | ||
|         # If this is continuing a previous session, pull the persisted data.
 | ||
|         if from_token:
 | ||
|             try:
 | ||
|                 pagination_session = await self._store.get_session(
 | ||
|                     session_type=self._PAGINATION_SESSION_TYPE,
 | ||
|                     session_id=from_token,
 | ||
|                 )
 | ||
|             except StoreError:
 | ||
|                 raise SynapseError(400, "Unknown pagination token", Codes.INVALID_PARAM)
 | ||
| 
 | ||
|             # If the requester, room ID, suggested-only, or max depth were modified
 | ||
|             # the session is invalid.
 | ||
|             if (
 | ||
|                 requester != pagination_session["requester"]
 | ||
|                 or requested_room_id != pagination_session["room_id"]
 | ||
|                 or suggested_only != pagination_session["suggested_only"]
 | ||
|                 or max_depth != pagination_session["max_depth"]
 | ||
|             ):
 | ||
|                 raise SynapseError(400, "Unknown pagination token", Codes.INVALID_PARAM)
 | ||
| 
 | ||
|             # Load the previous state.
 | ||
|             room_queue = [
 | ||
|                 _RoomQueueEntry(*fields) for fields in pagination_session["room_queue"]
 | ||
|             ]
 | ||
|             processed_rooms = set(pagination_session["processed_rooms"])
 | ||
|         else:
 | ||
|             # The queue of rooms to process, the next room is last on the stack.
 | ||
|             room_queue = [_RoomQueueEntry(requested_room_id, ())]
 | ||
| 
 | ||
|             # Rooms we have already processed.
 | ||
|             processed_rooms = set()
 | ||
| 
 | ||
|         rooms_result: List[JsonDict] = []
 | ||
| 
 | ||
|         # Cap the limit to a server-side maximum.
 | ||
|         if limit is None:
 | ||
|             limit = MAX_ROOMS
 | ||
|         else:
 | ||
|             limit = min(limit, MAX_ROOMS)
 | ||
| 
 | ||
|         # Iterate through the queue until we reach the limit or run out of
 | ||
|         # rooms to include.
 | ||
|         while room_queue and len(rooms_result) < limit:
 | ||
|             queue_entry = room_queue.pop()
 | ||
|             room_id = queue_entry.room_id
 | ||
|             current_depth = queue_entry.depth
 | ||
|             if room_id in processed_rooms:
 | ||
|                 # already done this room
 | ||
|                 continue
 | ||
| 
 | ||
|             logger.debug("Processing room %s", room_id)
 | ||
| 
 | ||
|             # A map of summaries for children rooms that might be returned over
 | ||
|             # federation. The rationale for caching these and *maybe* using them
 | ||
|             # is to prefer any information local to the homeserver before trusting
 | ||
|             # data received over federation.
 | ||
|             children_room_entries: Dict[str, JsonDict] = {}
 | ||
|             # A set of room IDs which are children that did not have information
 | ||
|             # returned over federation and are known to be inaccessible to the
 | ||
|             # current server. We should not reach out over federation to try to
 | ||
|             # summarise these rooms.
 | ||
|             inaccessible_children: Set[str] = set()
 | ||
| 
 | ||
|             # If the room is known locally, summarise it!
 | ||
|             is_in_room = await self._store.is_host_joined(room_id, self._server_name)
 | ||
|             if is_in_room:
 | ||
|                 room_entry = await self._summarize_local_room(
 | ||
|                     requester,
 | ||
|                     None,
 | ||
|                     room_id,
 | ||
|                     suggested_only,
 | ||
|                     # TODO Handle max children.
 | ||
|                     max_children=None,
 | ||
|                 )
 | ||
| 
 | ||
|             # Otherwise, attempt to use information for federation.
 | ||
|             else:
 | ||
|                 # A previous call might have included information for this room.
 | ||
|                 # It can be used if either:
 | ||
|                 #
 | ||
|                 # 1. The room is not a space.
 | ||
|                 # 2. The maximum depth has been achieved (since no children
 | ||
|                 #    information is needed).
 | ||
|                 if queue_entry.remote_room and (
 | ||
|                     queue_entry.remote_room.get("room_type") != RoomTypes.SPACE
 | ||
|                     or (max_depth is not None and current_depth >= max_depth)
 | ||
|                 ):
 | ||
|                     room_entry = _RoomEntry(
 | ||
|                         queue_entry.room_id, queue_entry.remote_room
 | ||
|                     )
 | ||
| 
 | ||
|                 # If the above isn't true, attempt to fetch the room
 | ||
|                 # information over federation.
 | ||
|                 else:
 | ||
|                     (
 | ||
|                         room_entry,
 | ||
|                         children_room_entries,
 | ||
|                         inaccessible_children,
 | ||
|                     ) = await self._summarize_remote_room_hierarchy(
 | ||
|                         queue_entry,
 | ||
|                         suggested_only,
 | ||
|                     )
 | ||
| 
 | ||
|                 # Ensure this room is accessible to the requester (and not just
 | ||
|                 # the homeserver).
 | ||
|                 if room_entry and not await self._is_remote_room_accessible(
 | ||
|                     requester, queue_entry.room_id, room_entry.room
 | ||
|                 ):
 | ||
|                     room_entry = None
 | ||
| 
 | ||
|             # This room has been processed and should be ignored if it appears
 | ||
|             # elsewhere in the hierarchy.
 | ||
|             processed_rooms.add(room_id)
 | ||
| 
 | ||
|             # There may or may not be a room entry based on whether it is
 | ||
|             # inaccessible to the requesting user.
 | ||
|             if room_entry:
 | ||
|                 # Add the room (including the stripped m.space.child events).
 | ||
|                 rooms_result.append(room_entry.as_json())
 | ||
| 
 | ||
|                 # If this room is not at the max-depth, check if there are any
 | ||
|                 # children to process.
 | ||
|                 if max_depth is None or current_depth < max_depth:
 | ||
|                     # The children get added in reverse order so that the next
 | ||
|                     # room to process, according to the ordering, is the last
 | ||
|                     # item in the list.
 | ||
|                     room_queue.extend(
 | ||
|                         _RoomQueueEntry(
 | ||
|                             ev["state_key"],
 | ||
|                             ev["content"]["via"],
 | ||
|                             current_depth + 1,
 | ||
|                             children_room_entries.get(ev["state_key"]),
 | ||
|                         )
 | ||
|                         for ev in reversed(room_entry.children_state_events)
 | ||
|                         if ev["type"] == EventTypes.SpaceChild
 | ||
|                         and ev["state_key"] not in inaccessible_children
 | ||
|                     )
 | ||
| 
 | ||
|         result: JsonDict = {"rooms": rooms_result}
 | ||
| 
 | ||
|         # If there's additional data, generate a pagination token (and persist state).
 | ||
|         if room_queue:
 | ||
|             result["next_batch"] = await self._store.create_session(
 | ||
|                 session_type=self._PAGINATION_SESSION_TYPE,
 | ||
|                 value={
 | ||
|                     # Information which must be identical across pagination.
 | ||
|                     "requester": requester,
 | ||
|                     "room_id": requested_room_id,
 | ||
|                     "suggested_only": suggested_only,
 | ||
|                     "max_depth": max_depth,
 | ||
|                     # The stored state.
 | ||
|                     "room_queue": [
 | ||
|                         attr.astuple(room_entry) for room_entry in room_queue
 | ||
|                     ],
 | ||
|                     "processed_rooms": list(processed_rooms),
 | ||
|                 },
 | ||
|                 expiry_ms=self._PAGINATION_SESSION_VALIDITY_PERIOD_MS,
 | ||
|             )
 | ||
| 
 | ||
|         return result
 | ||
| 
 | ||
|     async def federation_space_summary(
 | ||
|         self,
 | ||
|         origin: str,
 | ||
|         room_id: str,
 | ||
|         suggested_only: bool,
 | ||
|         max_rooms_per_space: Optional[int],
 | ||
|         exclude_rooms: Iterable[str],
 | ||
|     ) -> JsonDict:
 | ||
|         """
 | ||
|         Implementation of the space summary Federation API
 | ||
| 
 | ||
|         Args:
 | ||
|             origin: The server requesting the spaces summary.
 | ||
| 
 | ||
|             room_id: room id to start the summary at
 | ||
| 
 | ||
|             suggested_only: whether we should only return children with the "suggested"
 | ||
|                 flag set.
 | ||
| 
 | ||
|             max_rooms_per_space: an optional limit on the number of child rooms we will
 | ||
|                 return. Unlike the C-S API, this applies to the root room (room_id).
 | ||
|                 It is clipped to MAX_ROOMS_PER_SPACE.
 | ||
| 
 | ||
|             exclude_rooms: a list of rooms to skip over (presumably because the
 | ||
|                 calling server has already seen them).
 | ||
| 
 | ||
|         Returns:
 | ||
|             summary dict to return
 | ||
|         """
 | ||
|         # the queue of rooms to process
 | ||
|         room_queue = deque((room_id,))
 | ||
| 
 | ||
|         # the set of rooms that we should not walk further. Initialise it with the
 | ||
|         # excluded-rooms list; we will add other rooms as we process them so that
 | ||
|         # we do not loop.
 | ||
|         processed_rooms: Set[str] = set(exclude_rooms)
 | ||
| 
 | ||
|         rooms_result: List[JsonDict] = []
 | ||
|         events_result: List[JsonDict] = []
 | ||
| 
 | ||
|         while room_queue and len(rooms_result) < MAX_ROOMS:
 | ||
|             room_id = room_queue.popleft()
 | ||
|             if room_id in processed_rooms:
 | ||
|                 # already done this room
 | ||
|                 continue
 | ||
| 
 | ||
|             room_entry = await self._summarize_local_room(
 | ||
|                 None, origin, room_id, suggested_only, max_rooms_per_space
 | ||
|             )
 | ||
| 
 | ||
|             processed_rooms.add(room_id)
 | ||
| 
 | ||
|             if room_entry:
 | ||
|                 rooms_result.append(room_entry.room)
 | ||
|                 events_result.extend(room_entry.children_state_events)
 | ||
| 
 | ||
|                 # add any children to the queue
 | ||
|                 room_queue.extend(
 | ||
|                     edge_event["state_key"]
 | ||
|                     for edge_event in room_entry.children_state_events
 | ||
|                 )
 | ||
| 
 | ||
|         return {"rooms": rooms_result, "events": events_result}
 | ||
| 
 | ||
|     async def get_federation_hierarchy(
 | ||
|         self,
 | ||
|         origin: str,
 | ||
|         requested_room_id: str,
 | ||
|         suggested_only: bool,
 | ||
|     ):
 | ||
|         """
 | ||
|         Implementation of the room hierarchy Federation API.
 | ||
| 
 | ||
|         This is similar to get_room_hierarchy, but does not recurse into the space.
 | ||
|         It also considers whether anyone on the server may be able to access the
 | ||
|         room, as opposed to whether a specific user can.
 | ||
| 
 | ||
|         Args:
 | ||
|             origin: The server requesting the spaces summary.
 | ||
|             requested_room_id: The room ID to start the hierarchy at (the "root" room).
 | ||
|             suggested_only: whether we should only return children with the "suggested"
 | ||
|                 flag set.
 | ||
| 
 | ||
|         Returns:
 | ||
|             The JSON hierarchy dictionary.
 | ||
|         """
 | ||
|         root_room_entry = await self._summarize_local_room(
 | ||
|             None, origin, requested_room_id, suggested_only, max_children=None
 | ||
|         )
 | ||
|         if root_room_entry is None:
 | ||
|             # Room is inaccessible to the requesting server.
 | ||
|             raise SynapseError(404, "Unknown room: %s" % (requested_room_id,))
 | ||
| 
 | ||
|         children_rooms_result: List[JsonDict] = []
 | ||
|         inaccessible_children: List[str] = []
 | ||
| 
 | ||
|         # Iterate through each child and potentially add it, but not its children,
 | ||
|         # to the response.
 | ||
|         for child_room in root_room_entry.children_state_events:
 | ||
|             room_id = child_room.get("state_key")
 | ||
|             assert isinstance(room_id, str)
 | ||
|             # If the room is unknown, skip it.
 | ||
|             if not await self._store.is_host_joined(room_id, self._server_name):
 | ||
|                 continue
 | ||
| 
 | ||
|             room_entry = await self._summarize_local_room(
 | ||
|                 None, origin, room_id, suggested_only, max_children=0
 | ||
|             )
 | ||
|             # If the room is accessible, include it in the results.
 | ||
|             #
 | ||
|             # Note that only the room summary (without information on children)
 | ||
|             # is included in the summary.
 | ||
|             if room_entry:
 | ||
|                 children_rooms_result.append(room_entry.room)
 | ||
|             #  Otherwise, note that the requesting server shouldn't bother
 | ||
|             #  trying to summarize this room - they do not have access to it.
 | ||
|             else:
 | ||
|                 inaccessible_children.append(room_id)
 | ||
| 
 | ||
|         return {
 | ||
|             # Include the requested room (including the stripped children events).
 | ||
|             "room": root_room_entry.as_json(),
 | ||
|             "children": children_rooms_result,
 | ||
|             "inaccessible_children": inaccessible_children,
 | ||
|         }
 | ||
| 
 | ||
|     async def _summarize_local_room(
 | ||
|         self,
 | ||
|         requester: Optional[str],
 | ||
|         origin: Optional[str],
 | ||
|         room_id: str,
 | ||
|         suggested_only: bool,
 | ||
|         max_children: Optional[int],
 | ||
|     ) -> Optional["_RoomEntry"]:
 | ||
|         """
 | ||
|         Generate a room entry and a list of event entries for a given room.
 | ||
| 
 | ||
|         Args:
 | ||
|             requester:
 | ||
|                 The user requesting the summary, if it is a local request. None
 | ||
|                 if this is a federation request.
 | ||
|             origin:
 | ||
|                 The server requesting the summary, if it is a federation request.
 | ||
|                 None if this is a local request.
 | ||
|             room_id: The room ID to summarize.
 | ||
|             suggested_only: True if only suggested children should be returned.
 | ||
|                 Otherwise, all children are returned.
 | ||
|             max_children:
 | ||
|                 The maximum number of children rooms to include. This is capped
 | ||
|                 to a server-set limit.
 | ||
| 
 | ||
|         Returns:
 | ||
|             A room entry if the room should be returned. None, otherwise.
 | ||
|         """
 | ||
|         if not await self._is_local_room_accessible(room_id, requester, origin):
 | ||
|             return None
 | ||
| 
 | ||
|         room_entry = await self._build_room_entry(room_id, for_federation=bool(origin))
 | ||
| 
 | ||
|         # If the room is not a space or the children don't matter, return just
 | ||
|         # the room information.
 | ||
|         if room_entry.get("room_type") != RoomTypes.SPACE or max_children == 0:
 | ||
|             return _RoomEntry(room_id, room_entry)
 | ||
| 
 | ||
|         # Otherwise, look for child rooms/spaces.
 | ||
|         child_events = await self._get_child_events(room_id)
 | ||
| 
 | ||
|         if suggested_only:
 | ||
|             # we only care about suggested children
 | ||
|             child_events = filter(_is_suggested_child_event, child_events)
 | ||
| 
 | ||
|         if max_children is None or max_children > MAX_ROOMS_PER_SPACE:
 | ||
|             max_children = MAX_ROOMS_PER_SPACE
 | ||
| 
 | ||
|         stripped_events: List[JsonDict] = [
 | ||
|             {
 | ||
|                 "type": e.type,
 | ||
|                 "state_key": e.state_key,
 | ||
|                 "content": e.content,
 | ||
|                 "room_id": e.room_id,
 | ||
|                 "sender": e.sender,
 | ||
|                 "origin_server_ts": e.origin_server_ts,
 | ||
|             }
 | ||
|             for e in itertools.islice(child_events, max_children)
 | ||
|         ]
 | ||
|         return _RoomEntry(room_id, room_entry, stripped_events)
 | ||
| 
 | ||
|     async def _summarize_remote_room(
 | ||
|         self,
 | ||
|         room: "_RoomQueueEntry",
 | ||
|         suggested_only: bool,
 | ||
|         max_children: Optional[int],
 | ||
|         exclude_rooms: Iterable[str],
 | ||
|     ) -> Iterable["_RoomEntry"]:
 | ||
|         """
 | ||
|         Request room entries and a list of event entries for a given room by querying a remote server.
 | ||
| 
 | ||
|         Args:
 | ||
|             room: The room to summarize.
 | ||
|             suggested_only: True if only suggested children should be returned.
 | ||
|                 Otherwise, all children are returned.
 | ||
|             max_children:
 | ||
|                 The maximum number of children rooms to include. This is capped
 | ||
|                 to a server-set limit.
 | ||
|             exclude_rooms:
 | ||
|                 Rooms IDs which do not need to be summarized.
 | ||
| 
 | ||
|         Returns:
 | ||
|             An iterable of room entries.
 | ||
|         """
 | ||
|         room_id = room.room_id
 | ||
|         logger.info("Requesting summary for %s via %s", room_id, room.via)
 | ||
| 
 | ||
|         # we need to make the exclusion list json-serialisable
 | ||
|         exclude_rooms = list(exclude_rooms)
 | ||
| 
 | ||
|         via = itertools.islice(room.via, MAX_SERVERS_PER_SPACE)
 | ||
|         try:
 | ||
|             res = await self._federation_client.get_space_summary(
 | ||
|                 via,
 | ||
|                 room_id,
 | ||
|                 suggested_only=suggested_only,
 | ||
|                 max_rooms_per_space=max_children,
 | ||
|                 exclude_rooms=exclude_rooms,
 | ||
|             )
 | ||
|         except Exception as e:
 | ||
|             logger.warning(
 | ||
|                 "Unable to get summary of %s via federation: %s",
 | ||
|                 room_id,
 | ||
|                 e,
 | ||
|                 exc_info=logger.isEnabledFor(logging.DEBUG),
 | ||
|             )
 | ||
|             return ()
 | ||
| 
 | ||
|         # Group the events by their room.
 | ||
|         children_by_room: Dict[str, List[JsonDict]] = {}
 | ||
|         for ev in res.events:
 | ||
|             if ev.event_type == EventTypes.SpaceChild:
 | ||
|                 children_by_room.setdefault(ev.room_id, []).append(ev.data)
 | ||
| 
 | ||
|         # Generate the final results.
 | ||
|         results = []
 | ||
|         for fed_room in res.rooms:
 | ||
|             fed_room_id = fed_room.get("room_id")
 | ||
|             if not fed_room_id or not isinstance(fed_room_id, str):
 | ||
|                 continue
 | ||
| 
 | ||
|             results.append(
 | ||
|                 _RoomEntry(
 | ||
|                     fed_room_id,
 | ||
|                     fed_room,
 | ||
|                     children_by_room.get(fed_room_id, []),
 | ||
|                 )
 | ||
|             )
 | ||
| 
 | ||
|         return results
 | ||
| 
 | ||
|     async def _summarize_remote_room_hierarchy(
 | ||
|         self, room: "_RoomQueueEntry", suggested_only: bool
 | ||
|     ) -> Tuple[Optional["_RoomEntry"], Dict[str, JsonDict], Set[str]]:
 | ||
|         """
 | ||
|         Request room entries and a list of event entries for a given room by querying a remote server.
 | ||
| 
 | ||
|         Args:
 | ||
|             room: The room to summarize.
 | ||
|             suggested_only: True if only suggested children should be returned.
 | ||
|                 Otherwise, all children are returned.
 | ||
| 
 | ||
|         Returns:
 | ||
|             A tuple of:
 | ||
|                 The room entry.
 | ||
|                 Partial room data return over federation.
 | ||
|                 A set of inaccessible children room IDs.
 | ||
|         """
 | ||
|         room_id = room.room_id
 | ||
|         logger.info("Requesting summary for %s via %s", room_id, room.via)
 | ||
| 
 | ||
|         via = itertools.islice(room.via, MAX_SERVERS_PER_SPACE)
 | ||
|         try:
 | ||
|             (
 | ||
|                 room_response,
 | ||
|                 children,
 | ||
|                 inaccessible_children,
 | ||
|             ) = await self._federation_client.get_room_hierarchy(
 | ||
|                 via,
 | ||
|                 room_id,
 | ||
|                 suggested_only=suggested_only,
 | ||
|             )
 | ||
|         except Exception as e:
 | ||
|             logger.warning(
 | ||
|                 "Unable to get hierarchy of %s via federation: %s",
 | ||
|                 room_id,
 | ||
|                 e,
 | ||
|                 exc_info=logger.isEnabledFor(logging.DEBUG),
 | ||
|             )
 | ||
|             return None, {}, set()
 | ||
| 
 | ||
|         # Map the children to their room ID.
 | ||
|         children_by_room_id = {
 | ||
|             c["room_id"]: c
 | ||
|             for c in children
 | ||
|             if "room_id" in c and isinstance(c["room_id"], str)
 | ||
|         }
 | ||
| 
 | ||
|         return (
 | ||
|             _RoomEntry(room_id, room_response, room_response.pop("children_state", ())),
 | ||
|             children_by_room_id,
 | ||
|             set(inaccessible_children),
 | ||
|         )
 | ||
| 
 | ||
|     async def _is_local_room_accessible(
 | ||
|         self, room_id: str, requester: Optional[str], origin: Optional[str] = None
 | ||
|     ) -> bool:
 | ||
|         """
 | ||
|         Calculate whether the room should be shown to the requester.
 | ||
| 
 | ||
|         It should return true if:
 | ||
| 
 | ||
|         * The requester is joined or can join the room (per MSC3173).
 | ||
|         * The origin server has any user that is joined or can join the room.
 | ||
|         * The history visibility is set to world readable.
 | ||
| 
 | ||
|         Args:
 | ||
|             room_id: The room ID to check accessibility of.
 | ||
|             requester:
 | ||
|                 The user making the request, if it is a local request.
 | ||
|                 None if this is a federation request.
 | ||
|             origin:
 | ||
|                 The server making the request, if it is a federation request.
 | ||
|                 None if this is a local request.
 | ||
| 
 | ||
|         Returns:
 | ||
|              True if the room is accessible to the requesting user or server.
 | ||
|         """
 | ||
|         state_ids = await self._store.get_current_state_ids(room_id)
 | ||
| 
 | ||
|         # If there's no state for the room, it isn't known.
 | ||
|         if not state_ids:
 | ||
|             # The user might have a pending invite for the room.
 | ||
|             if requester and await self._store.get_invite_for_local_user_in_room(
 | ||
|                 requester, room_id
 | ||
|             ):
 | ||
|                 return True
 | ||
| 
 | ||
|             logger.info("room %s is unknown, omitting from summary", room_id)
 | ||
|             return False
 | ||
| 
 | ||
|         try:
 | ||
|             room_version = await self._store.get_room_version(room_id)
 | ||
|         except UnsupportedRoomVersionError:
 | ||
|             # If a room with an unsupported room version is encountered, ignore
 | ||
|             # it to avoid breaking the entire summary response.
 | ||
|             return False
 | ||
| 
 | ||
|         # Include the room if it has join rules of public or knock.
 | ||
|         join_rules_event_id = state_ids.get((EventTypes.JoinRules, ""))
 | ||
|         if join_rules_event_id:
 | ||
|             join_rules_event = await self._store.get_event(join_rules_event_id)
 | ||
|             join_rule = join_rules_event.content.get("join_rule")
 | ||
|             if join_rule == JoinRules.PUBLIC or (
 | ||
|                 room_version.msc2403_knocking and join_rule == JoinRules.KNOCK
 | ||
|             ):
 | ||
|                 return True
 | ||
| 
 | ||
|         # Include the room if it is peekable.
 | ||
|         hist_vis_event_id = state_ids.get((EventTypes.RoomHistoryVisibility, ""))
 | ||
|         if hist_vis_event_id:
 | ||
|             hist_vis_ev = await self._store.get_event(hist_vis_event_id)
 | ||
|             hist_vis = hist_vis_ev.content.get("history_visibility")
 | ||
|             if hist_vis == HistoryVisibility.WORLD_READABLE:
 | ||
|                 return True
 | ||
| 
 | ||
|         # Otherwise we need to check information specific to the user or server.
 | ||
| 
 | ||
|         # If we have an authenticated requesting user, check if they are a member
 | ||
|         # of the room (or can join the room).
 | ||
|         if requester:
 | ||
|             member_event_id = state_ids.get((EventTypes.Member, requester), None)
 | ||
| 
 | ||
|             # If they're in the room they can see info on it.
 | ||
|             if member_event_id:
 | ||
|                 member_event = await self._store.get_event(member_event_id)
 | ||
|                 if member_event.membership in (Membership.JOIN, Membership.INVITE):
 | ||
|                     return True
 | ||
| 
 | ||
|             # Otherwise, check if they should be allowed access via membership in a space.
 | ||
|             if await self._event_auth_handler.has_restricted_join_rules(
 | ||
|                 state_ids, room_version
 | ||
|             ):
 | ||
|                 allowed_rooms = (
 | ||
|                     await self._event_auth_handler.get_rooms_that_allow_join(state_ids)
 | ||
|                 )
 | ||
|                 if await self._event_auth_handler.is_user_in_rooms(
 | ||
|                     allowed_rooms, requester
 | ||
|                 ):
 | ||
|                     return True
 | ||
| 
 | ||
|         # If this is a request over federation, check if the host is in the room or
 | ||
|         # has a user who could join the room.
 | ||
|         elif origin:
 | ||
|             if await self._event_auth_handler.check_host_in_room(
 | ||
|                 room_id, origin
 | ||
|             ) or await self._store.is_host_invited(room_id, origin):
 | ||
|                 return True
 | ||
| 
 | ||
|             # Alternately, if the host has a user in any of the spaces specified
 | ||
|             # for access, then the host can see this room (and should do filtering
 | ||
|             # if the requester cannot see it).
 | ||
|             if await self._event_auth_handler.has_restricted_join_rules(
 | ||
|                 state_ids, room_version
 | ||
|             ):
 | ||
|                 allowed_rooms = (
 | ||
|                     await self._event_auth_handler.get_rooms_that_allow_join(state_ids)
 | ||
|                 )
 | ||
|                 for space_id in allowed_rooms:
 | ||
|                     if await self._event_auth_handler.check_host_in_room(
 | ||
|                         space_id, origin
 | ||
|                     ):
 | ||
|                         return True
 | ||
| 
 | ||
|         logger.info(
 | ||
|             "room %s is unpeekable and requester %s is not a member / not allowed to join, omitting from summary",
 | ||
|             room_id,
 | ||
|             requester or origin,
 | ||
|         )
 | ||
|         return False
 | ||
| 
 | ||
|     async def _is_remote_room_accessible(
 | ||
|         self, requester: str, room_id: str, room: JsonDict
 | ||
|     ) -> bool:
 | ||
|         """
 | ||
|         Calculate whether the room received over federation should be shown to the requester.
 | ||
| 
 | ||
|         It should return true if:
 | ||
| 
 | ||
|         * The requester is joined or can join the room (per MSC3173).
 | ||
|         * The history visibility is set to world readable.
 | ||
| 
 | ||
|         Note that the local server is not in the requested room (which is why the
 | ||
|         remote call was made in the first place), but the user could have access
 | ||
|         due to an invite, etc.
 | ||
| 
 | ||
|         Args:
 | ||
|             requester: The user requesting the summary.
 | ||
|             room_id: The room ID returned over federation.
 | ||
|             room: The summary of the room returned over federation.
 | ||
| 
 | ||
|         Returns:
 | ||
|             True if the room is accessible to the requesting user.
 | ||
|         """
 | ||
|         # The API doesn't return the room version so assume that a
 | ||
|         # join rule of knock is valid.
 | ||
|         if (
 | ||
|             room.get("join_rules") in (JoinRules.PUBLIC, JoinRules.KNOCK)
 | ||
|             or room.get("world_readable") is True
 | ||
|         ):
 | ||
|             return True
 | ||
| 
 | ||
|         # Check if the user is a member of any of the allowed spaces
 | ||
|         # from the response.
 | ||
|         allowed_rooms = room.get("allowed_room_ids") or room.get("allowed_spaces")
 | ||
|         if allowed_rooms and isinstance(allowed_rooms, list):
 | ||
|             if await self._event_auth_handler.is_user_in_rooms(
 | ||
|                 allowed_rooms, requester
 | ||
|             ):
 | ||
|                 return True
 | ||
| 
 | ||
|         # Finally, check locally if we can access the room. The user might
 | ||
|         # already be in the room (if it was a child room), or there might be a
 | ||
|         # pending invite, etc.
 | ||
|         return await self._is_local_room_accessible(room_id, requester)
 | ||
| 
 | ||
|     async def _build_room_entry(self, room_id: str, for_federation: bool) -> JsonDict:
 | ||
|         """
 | ||
|         Generate en entry summarising a single room.
 | ||
| 
 | ||
|         Args:
 | ||
|             room_id: The room ID to summarize.
 | ||
|             for_federation: True if this is a summary requested over federation
 | ||
|                 (which includes additional fields).
 | ||
| 
 | ||
|         Returns:
 | ||
|             The JSON dictionary for the room.
 | ||
|         """
 | ||
|         stats = await self._store.get_room_with_stats(room_id)
 | ||
| 
 | ||
|         # currently this should be impossible because we call
 | ||
|         # _is_local_room_accessible on the room before we get here, so
 | ||
|         # there should always be an entry
 | ||
|         assert stats is not None, "unable to retrieve stats for %s" % (room_id,)
 | ||
| 
 | ||
|         current_state_ids = await self._store.get_current_state_ids(room_id)
 | ||
|         create_event = await self._store.get_event(
 | ||
|             current_state_ids[(EventTypes.Create, "")]
 | ||
|         )
 | ||
| 
 | ||
|         entry = {
 | ||
|             "room_id": stats["room_id"],
 | ||
|             "name": stats["name"],
 | ||
|             "topic": stats["topic"],
 | ||
|             "canonical_alias": stats["canonical_alias"],
 | ||
|             "num_joined_members": stats["joined_members"],
 | ||
|             "avatar_url": stats["avatar"],
 | ||
|             "join_rules": stats["join_rules"],
 | ||
|             "world_readable": (
 | ||
|                 stats["history_visibility"] == HistoryVisibility.WORLD_READABLE
 | ||
|             ),
 | ||
|             "guest_can_join": stats["guest_access"] == "can_join",
 | ||
|             "creation_ts": create_event.origin_server_ts,
 | ||
|             "room_type": create_event.content.get(EventContentFields.ROOM_TYPE),
 | ||
|         }
 | ||
| 
 | ||
|         # Federation requests need to provide additional information so the
 | ||
|         # requested server is able to filter the response appropriately.
 | ||
|         if for_federation:
 | ||
|             room_version = await self._store.get_room_version(room_id)
 | ||
|             if await self._event_auth_handler.has_restricted_join_rules(
 | ||
|                 current_state_ids, room_version
 | ||
|             ):
 | ||
|                 allowed_rooms = (
 | ||
|                     await self._event_auth_handler.get_rooms_that_allow_join(
 | ||
|                         current_state_ids
 | ||
|                     )
 | ||
|                 )
 | ||
|                 if allowed_rooms:
 | ||
|                     entry["allowed_room_ids"] = allowed_rooms
 | ||
|                     # TODO Remove this key once the API is stable.
 | ||
|                     entry["allowed_spaces"] = allowed_rooms
 | ||
| 
 | ||
|         # Filter out Nones – rather omit the field altogether
 | ||
|         room_entry = {k: v for k, v in entry.items() if v is not None}
 | ||
| 
 | ||
|         return room_entry
 | ||
| 
 | ||
|     async def _get_child_events(self, room_id: str) -> Iterable[EventBase]:
 | ||
|         """
 | ||
|         Get the child events for a given room.
 | ||
| 
 | ||
|         The returned results are sorted for stability.
 | ||
| 
 | ||
|         Args:
 | ||
|             room_id: The room id to get the children of.
 | ||
| 
 | ||
|         Returns:
 | ||
|             An iterable of sorted child events.
 | ||
|         """
 | ||
| 
 | ||
|         # look for child rooms/spaces.
 | ||
|         current_state_ids = await self._store.get_current_state_ids(room_id)
 | ||
| 
 | ||
|         events = await self._store.get_events_as_list(
 | ||
|             [
 | ||
|                 event_id
 | ||
|                 for key, event_id in current_state_ids.items()
 | ||
|                 if key[0] == EventTypes.SpaceChild
 | ||
|             ]
 | ||
|         )
 | ||
| 
 | ||
|         # filter out any events without a "via" (which implies it has been redacted),
 | ||
|         # and order to ensure we return stable results.
 | ||
|         return sorted(filter(_has_valid_via, events), key=_child_events_comparison_key)
 | ||
| 
 | ||
|     async def get_room_summary(
 | ||
|         self,
 | ||
|         requester: Optional[str],
 | ||
|         room_id: str,
 | ||
|         remote_room_hosts: Optional[List[str]] = None,
 | ||
|     ) -> JsonDict:
 | ||
|         """
 | ||
|         Implementation of the room summary C-S API from MSC3266
 | ||
| 
 | ||
|         Args:
 | ||
|             requester:  user id of the user making this request, will be None
 | ||
|                 for unauthenticated requests
 | ||
| 
 | ||
|             room_id: room id to summarise.
 | ||
| 
 | ||
|             remote_room_hosts: a list of homeservers to try fetching data through
 | ||
|                 if we don't know it ourselves
 | ||
| 
 | ||
|         Returns:
 | ||
|             summary dict to return
 | ||
|         """
 | ||
|         is_in_room = await self._store.is_host_joined(room_id, self._server_name)
 | ||
| 
 | ||
|         if is_in_room:
 | ||
|             room_entry = await self._summarize_local_room(
 | ||
|                 requester,
 | ||
|                 None,
 | ||
|                 room_id,
 | ||
|                 # Suggested-only doesn't matter since no children are requested.
 | ||
|                 suggested_only=False,
 | ||
|                 max_children=0,
 | ||
|             )
 | ||
| 
 | ||
|             if not room_entry:
 | ||
|                 raise NotFoundError("Room not found or is not accessible")
 | ||
| 
 | ||
|             room_summary = room_entry.room
 | ||
| 
 | ||
|             # If there was a requester, add their membership.
 | ||
|             if requester:
 | ||
|                 (
 | ||
|                     membership,
 | ||
|                     _,
 | ||
|                 ) = await self._store.get_local_current_membership_for_user_in_room(
 | ||
|                     requester, room_id
 | ||
|                 )
 | ||
| 
 | ||
|                 room_summary["membership"] = membership or "leave"
 | ||
|         else:
 | ||
|             # TODO federation API, descoped from initial unstable implementation
 | ||
|             #      as MSC needs more maturing on that side.
 | ||
|             raise SynapseError(400, "Federation is not currently supported.")
 | ||
| 
 | ||
|         return room_summary
 | ||
| 
 | ||
| 
 | ||
| @attr.s(frozen=True, slots=True, auto_attribs=True)
 | ||
| class _RoomQueueEntry:
 | ||
|     # The room ID of this entry.
 | ||
|     room_id: str
 | ||
|     # The server to query if the room is not known locally.
 | ||
|     via: Sequence[str]
 | ||
|     # The minimum number of hops necessary to get to this room (compared to the
 | ||
|     # originally requested room).
 | ||
|     depth: int = 0
 | ||
|     # The room summary for this room returned via federation. This will only be
 | ||
|     # used if the room is not known locally (and is not a space).
 | ||
|     remote_room: Optional[JsonDict] = None
 | ||
| 
 | ||
| 
 | ||
| @attr.s(frozen=True, slots=True, auto_attribs=True)
 | ||
| class _RoomEntry:
 | ||
|     room_id: str
 | ||
|     # The room summary for this room.
 | ||
|     room: JsonDict
 | ||
|     # An iterable of the sorted, stripped children events for children of this room.
 | ||
|     #
 | ||
|     # This may not include all children.
 | ||
|     children_state_events: Sequence[JsonDict] = ()
 | ||
| 
 | ||
|     def as_json(self) -> JsonDict:
 | ||
|         """
 | ||
|         Returns a JSON dictionary suitable for the room hierarchy endpoint.
 | ||
| 
 | ||
|         It returns the room summary including the stripped m.space.child events
 | ||
|         as a sub-key.
 | ||
|         """
 | ||
|         result = dict(self.room)
 | ||
|         result["children_state"] = self.children_state_events
 | ||
|         return result
 | ||
| 
 | ||
| 
 | ||
| def _has_valid_via(e: EventBase) -> bool:
 | ||
|     via = e.content.get("via")
 | ||
|     if not via or not isinstance(via, Sequence):
 | ||
|         return False
 | ||
|     for v in via:
 | ||
|         if not isinstance(v, str):
 | ||
|             logger.debug("Ignoring edge event %s with invalid via entry", e.event_id)
 | ||
|             return False
 | ||
|     return True
 | ||
| 
 | ||
| 
 | ||
| def _is_suggested_child_event(edge_event: EventBase) -> bool:
 | ||
|     suggested = edge_event.content.get("suggested")
 | ||
|     if isinstance(suggested, bool) and suggested:
 | ||
|         return True
 | ||
|     logger.debug("Ignorning not-suggested child %s", edge_event.state_key)
 | ||
|     return False
 | ||
| 
 | ||
| 
 | ||
| # Order may only contain characters in the range of \x20 (space) to \x7E (~) inclusive.
 | ||
| _INVALID_ORDER_CHARS_RE = re.compile(r"[^\x20-\x7E]")
 | ||
| 
 | ||
| 
 | ||
| def _child_events_comparison_key(
 | ||
|     child: EventBase,
 | ||
| ) -> Tuple[bool, Optional[str], int, str]:
 | ||
|     """
 | ||
|     Generate a value for comparing two child events for ordering.
 | ||
| 
 | ||
|     The rules for ordering are:
 | ||
| 
 | ||
|     1. The 'order' key, if it is valid.
 | ||
|     2. The 'origin_server_ts' of the 'm.space.child' event.
 | ||
|     3. The 'room_id'.
 | ||
| 
 | ||
|     Args:
 | ||
|         child: The event for generating a comparison key.
 | ||
| 
 | ||
|     Returns:
 | ||
|         The comparison key as a tuple of:
 | ||
|             False if the ordering is valid.
 | ||
|             The 'order' field or None if it is not given or invalid.
 | ||
|             The 'origin_server_ts' field.
 | ||
|             The room ID.
 | ||
|     """
 | ||
|     order = child.content.get("order")
 | ||
|     # If order is not a string or doesn't meet the requirements, ignore it.
 | ||
|     if not isinstance(order, str):
 | ||
|         order = None
 | ||
|     elif len(order) > 50 or _INVALID_ORDER_CHARS_RE.search(order):
 | ||
|         order = None
 | ||
| 
 | ||
|     # Items without an order come last.
 | ||
|     return (order is None, order, child.origin_server_ts, child.room_id)
 |