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- # Copyright 2021 The Matrix.org Foundation C.I.C.
- #
- # 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 typing import TYPE_CHECKING, Dict, Iterable, List, Optional, Sequence, Set, Tuple
- import attr
- from synapse.api.constants import (
- EventContentFields,
- EventTypes,
- HistoryVisibility,
- JoinRules,
- Membership,
- RoomTypes,
- )
- from synapse.api.errors import (
- AuthError,
- Codes,
- NotFoundError,
- StoreError,
- SynapseError,
- UnsupportedRoomVersionError,
- )
- from synapse.api.ratelimiting import Ratelimiter
- from synapse.events import EventBase
- from synapse.types import JsonDict, Requester
- from synapse.util.caches.response_cache import ResponseCache
- if TYPE_CHECKING:
- from synapse.server import HomeServer
- logger = logging.getLogger(__name__)
- # number of rooms to return. We'll stop once we hit this limit.
- MAX_ROOMS = 50
- # max number of events to return per room.
- MAX_ROOMS_PER_SPACE = 50
- # max number of federation servers to hit per room
- MAX_SERVERS_PER_SPACE = 3
- @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.
- _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"):
- self._event_auth_handler = hs.get_event_auth_handler()
- self._store = hs.get_datastores().main
- self._event_serializer = hs.get_event_client_serializer()
- self._server_name = hs.hostname
- self._federation_client = hs.get_federation_client()
- self._ratelimiter = Ratelimiter(
- store=self._store, clock=hs.get_clock(), rate_hz=5, burst_count=10
- )
- # 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.
- self._pagination_response_cache: ResponseCache[
- Tuple[str, str, bool, Optional[int], Optional[int], Optional[str]]
- ] = ResponseCache(
- hs.get_clock(),
- "get_room_hierarchy",
- )
- self._msc3266_enabled = hs.config.experimental.msc3266_enabled
- async def get_room_hierarchy(
- self,
- requester: Requester,
- requested_room_id: str,
- 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
- page. Must be a positive integer.
- from_token: An optional pagination token.
- Returns:
- The JSON hierarchy dictionary.
- """
- await self._ratelimiter.ratelimit(requester)
- # 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(
- (
- requester.user.to_string(),
- requested_room_id,
- suggested_only,
- max_depth,
- limit,
- from_token,
- ),
- self._get_room_hierarchy,
- requester.user.to_string(),
- 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,
- )
- # 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(for_client=True))
- # 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 get_federation_hierarchy(
- self,
- origin: str,
- requested_room_id: str,
- suggested_only: bool,
- ) -> JsonDict:
- """
- 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
- )
- 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 itertools.islice(
- root_room_entry.children_state_events, MAX_ROOMS_PER_SPACE
- ):
- 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, include_children=False
- )
- # 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,
- include_children: bool = True,
- ) -> 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.
- include_children:
- Whether to include the events of any children.
- 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 return just the room information.
- if room_entry.get("room_type") != RoomTypes.SPACE or not include_children:
- 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)
- 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 child_events
- ]
- return _RoomEntry(room_id, room_entry, stripped_events)
- 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_state_events,
- 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, children_state_events),
- 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)
- or (
- room_version.msc3787_knock_restricted_join_rule
- and join_rule == JoinRules.KNOCK_RESTRICTED
- )
- ):
- 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: Optional[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. If not passed only world
- readability is checked.
- 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
- elif not requester:
- return False
- # Check if the user is a member of any of the allowed rooms from the response.
- allowed_rooms = room.get("allowed_room_ids")
- 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"],
- # plural join_rules is a documentation error but kept for historical
- # purposes. Should match /publicRooms.
- "join_rules": stats["join_rules"],
- "join_rule": stats["join_rules"],
- "world_readable": (
- stats["history_visibility"] == HistoryVisibility.WORLD_READABLE
- ),
- "guest_can_join": stats["guest_access"] == "can_join",
- "room_type": create_event.content.get(EventContentFields.ROOM_TYPE),
- }
- if self._msc3266_enabled:
- entry["im.nheko.summary.version"] = stats["version"]
- entry["im.nheko.summary.encryption"] = stats["encryption"]
- # 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
- # 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,
- include_children=False,
- )
- 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:
- # Reuse the hierarchy query over federation
- if remote_room_hosts is None:
- raise SynapseError(400, "Missing via to query remote room")
- (
- room_entry,
- children_room_entries,
- inaccessible_children,
- ) = await self._summarize_remote_room_hierarchy(
- _RoomQueueEntry(room_id, remote_room_hosts),
- suggested_only=True,
- )
- # The results over federation might include rooms that we, as the
- # requesting server, are allowed to see, but the requesting user is
- # not permitted to see.
- #
- # Filter the returned results to only what is accessible to the user.
- if not room_entry or not await self._is_remote_room_accessible(
- requester, room_entry.room_id, room_entry.room
- ):
- raise NotFoundError("Room not found or is not accessible")
- room = dict(room_entry.room)
- room.pop("allowed_room_ids", None)
- # If there was a requester, add their membership.
- # We keep the membership in the local membership table unless the
- # room is purged even for remote rooms.
- if requester:
- (
- membership,
- _,
- ) = await self._store.get_local_current_membership_for_user_in_room(
- requester, room_id
- )
- room["membership"] = membership or "leave"
- return room
- 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, for_client: bool = False) -> 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.
- Args:
- for_client: If true, any server-server only fields are stripped from
- the result.
- """
- result = dict(self.room)
- # Before returning to the client, remove the allowed_room_ids key, if it
- # exists.
- if for_client:
- result.pop("allowed_room_ids", False)
- 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, list):
- 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
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