Experimental support for MSC3266 Room Summary API. (#10394)

Author: t3chguy

changelog.d/10394.feature

@@ -0,0 +1 @@
+Initial local support for [MSC3266](https://github.com/matrix-org/synapse/pull/10394), Room Summary over the unstable `/rooms/{roomIdOrAlias}/summary` API.

mypy.ini

@@ -86,7 +86,7 @@ files =
   tests/test_event_auth.py,
   tests/test_utils,
   tests/handlers/test_password_providers.py,
-  tests/handlers/test_space_summary.py,
+  tests/handlers/test_room_summary.py,
   tests/rest/client/v1/test_login.py,
   tests/rest/client/v2_alpha/test_auth.py,
   tests/util/test_itertools.py,

synapse/config/experimental.py

@@ -38,3 +38,6 @@ def read_config(self, config: JsonDict, **kwargs):
 
         # MSC3244 (room version capabilities)
         self.msc3244_enabled: bool = experimental.get("msc3244_enabled", False)
+
+        # MSC3266 (room summary api)
+        self.msc3266_enabled: bool = experimental.get("msc3266_enabled", False)

synapse/federation/transport/server/federation.py

@@ -547,7 +547,7 @@ def __init__(
         server_name: str,
     ):
         super().__init__(hs, authenticator, ratelimiter, server_name)
-        self.handler = hs.get_space_summary_handler()
+        self.handler = hs.get_room_summary_handler()
 
     async def on_GET(
         self,
@@ -608,7 +608,7 @@ def __init__(
         server_name: str,
     ):
         super().__init__(hs, authenticator, ratelimiter, server_name)
-        self.handler = hs.get_space_summary_handler()
+        self.handler = hs.get_room_summary_handler()
 
     async def on_GET(
         self,

synapse/handlers/space_summary.py synapse/handlers/room_summary.pysynapse/handlers/space_summary.py renamed to synapse/handlers/room_summary.py

@@ -28,7 +28,7 @@
     Membership,
     RoomTypes,
 )
-from synapse.api.errors import AuthError, Codes, SynapseError
+from synapse.api.errors import AuthError, Codes, NotFoundError, SynapseError
 from synapse.events import EventBase
 from synapse.events.utils import format_event_for_client_v2
 from synapse.types import JsonDict
@@ -75,7 +75,7 @@ class _PaginationSession:
     processed_rooms: Set[str]
 
 
-class SpaceSummaryHandler:
+class RoomSummaryHandler:
     # The time a pagination session remains valid for.
     _PAGINATION_SESSION_VALIDITY_PERIOD_MS = 5 * 60 * 1000
 
@@ -412,7 +412,7 @@ async def _get_room_hierarchy(
                         room_entry,
                         children_room_entries,
                         inaccessible_children,
-                    ) = await self._summarize_remote_room_hiearchy(
+                    ) = await self._summarize_remote_room_hierarchy(
                         queue_entry,
                         suggested_only,
                     )
@@ -724,7 +724,7 @@ async def _summarize_remote_room(
 
         return results
 
-    async def _summarize_remote_room_hiearchy(
+    async def _summarize_remote_room_hierarchy(
         self, room: "_RoomQueueEntry", suggested_only: bool
     ) -> Tuple[Optional["_RoomEntry"], Dict[str, JsonDict], Set[str]]:
         """
@@ -781,25 +781,25 @@ 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 in the spaces summary.
+        Calculate whether the room should be shown to the requester.
 
-        It should be included if:
+        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 summarize.
+            room_id: The room ID to check accessibility of.
             requester:
-                The user requesting the summary, if it is a local request. None
-                if this is a federation request.
+                The user making the request, 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.
+                The server making the request, if it is a federation request.
                 None if this is a local request.
 
         Returns:
-             True if the room should be included in the spaces summary.
+             True if the room is accessible to the requesting user or server.
         """
         state_ids = await self._store.get_current_state_ids(room_id)
 
@@ -893,9 +893,9 @@ 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 in the spaces summary.
+        Calculate whether the room received over federation should be shown to the requester.
 
-        It should be included if:
+        It should return true if:
 
         * The requester is joined or can join the room (per MSC3173).
         * The history visibility is set to world readable.
@@ -907,10 +907,10 @@ async def _is_remote_room_accessible(
         Args:
             requester: The user requesting the summary.
             room_id: The room ID returned over federation.
-            room: The summary of the child room returned over federation.
+            room: The summary of the room returned over federation.
 
         Returns:
-            True if the room should be included in the spaces summary.
+            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.
@@ -936,7 +936,7 @@ async def _is_remote_room_accessible(
 
     async def _build_room_entry(self, room_id: str, for_federation: bool) -> JsonDict:
         """
-        Generate en entry suitable for the 'rooms' list in the summary response.
+        Generate en entry summarising a single room.
 
         Args:
             room_id: The room ID to summarize.
@@ -1024,6 +1024,61 @@ async def _get_child_events(self, room_id: str) -> Iterable[EventBase]:
         # 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:

synapse/http/servlet.py

@@ -14,16 +14,28 @@
 
 """ This module contains base REST classes for constructing REST servlets. """
 import logging
-from typing import Iterable, List, Mapping, Optional, Sequence, overload
+from typing import (
+    TYPE_CHECKING,
+    Iterable,
+    List,
+    Mapping,
+    Optional,
+    Sequence,
+    Tuple,
+    overload,
+)
 
 from typing_extensions import Literal
 
 from twisted.web.server import Request
 
 from synapse.api.errors import Codes, SynapseError
-from synapse.types import JsonDict
+from synapse.types import JsonDict, RoomAlias, RoomID
 from synapse.util import json_decoder
 
+if TYPE_CHECKING:
+    from synapse.server import HomeServer
+
 logger = logging.getLogger(__name__)
 
 
@@ -663,3 +675,45 @@ def register(self, http_server):
 
         else:
             raise NotImplementedError("RestServlet must register something.")
+
+
+class ResolveRoomIdMixin:
+    def __init__(self, hs: "HomeServer"):
+        self.room_member_handler = hs.get_room_member_handler()
+
+    async def resolve_room_id(
+        self, room_identifier: str, remote_room_hosts: Optional[List[str]] = None
+    ) -> Tuple[str, Optional[List[str]]]:
+        """
+        Resolve a room identifier to a room ID, if necessary.
+
+        This also performanes checks to ensure the room ID is of the proper form.
+
+        Args:
+            room_identifier: The room ID or alias.
+            remote_room_hosts: The potential remote room hosts to use.
+
+        Returns:
+            The resolved room ID.
+
+        Raises:
+            SynapseError if the room ID is of the wrong form.
+        """
+        if RoomID.is_valid(room_identifier):
+            resolved_room_id = room_identifier
+        elif RoomAlias.is_valid(room_identifier):
+            room_alias = RoomAlias.from_string(room_identifier)
+            (
+                room_id,
+                remote_room_hosts,
+            ) = await self.room_member_handler.lookup_room_alias(room_alias)
+            resolved_room_id = room_id.to_string()
+        else:
+            raise SynapseError(
+                400, "%s was not legal room ID or room alias" % (room_identifier,)
+            )
+        if not resolved_room_id:
+            raise SynapseError(
+                400, "Unknown room ID or room alias %s" % room_identifier
+            )
+        return resolved_room_id, remote_room_hosts

synapse/rest/admin/rooms.py

@@ -20,6 +20,7 @@
 from synapse.api.errors import AuthError, Codes, NotFoundError, SynapseError
 from synapse.api.filtering import Filter
 from synapse.http.servlet import (
+    ResolveRoomIdMixin,
     RestServlet,
     assert_params_in_dict,
     parse_integer,
@@ -33,7 +34,7 @@
     assert_user_is_admin,
 )
 from synapse.storage.databases.main.room import RoomSortOrder
-from synapse.types import JsonDict, RoomAlias, RoomID, UserID, create_requester
+from synapse.types import JsonDict, UserID, create_requester
 from synapse.util import json_decoder
 
 if TYPE_CHECKING:
@@ -45,48 +46,6 @@
 logger = logging.getLogger(__name__)
 
 
-class ResolveRoomIdMixin:
-    def __init__(self, hs: "HomeServer"):
-        self.room_member_handler = hs.get_room_member_handler()
-
-    async def resolve_room_id(
-        self, room_identifier: str, remote_room_hosts: Optional[List[str]] = None
-    ) -> Tuple[str, Optional[List[str]]]:
-        """
-        Resolve a room identifier to a room ID, if necessary.
-
-        This also performanes checks to ensure the room ID is of the proper form.
-
-        Args:
-            room_identifier: The room ID or alias.
-            remote_room_hosts: The potential remote room hosts to use.
-
-        Returns:
-            The resolved room ID.
-
-        Raises:
-            SynapseError if the room ID is of the wrong form.
-        """
-        if RoomID.is_valid(room_identifier):
-            resolved_room_id = room_identifier
-        elif RoomAlias.is_valid(room_identifier):
-            room_alias = RoomAlias.from_string(room_identifier)
-            (
-                room_id,
-                remote_room_hosts,
-            ) = await self.room_member_handler.lookup_room_alias(room_alias)
-            resolved_room_id = room_id.to_string()
-        else:
-            raise SynapseError(
-                400, "%s was not legal room ID or room alias" % (room_identifier,)
-            )
-        if not resolved_room_id:
-            raise SynapseError(
-                400, "Unknown room ID or room alias %s" % room_identifier
-            )
-        return resolved_room_id, remote_room_hosts
-
-
 class ShutdownRoomRestServlet(RestServlet):
     """Shuts down a room by removing all local users from the room and blocking
     all future invites and joins to the room. Any local aliases will be repointed