Add /user/{user_id}/shared_rooms/ api

changelog.d/7785.feature

@@ -0,0 +1 @@
+Add an endpoint to query your shared rooms with another user as an implementation of [MSC2666](https://github.com/matrix-org/matrix-doc/pull/2666).

synapse/rest/__init__.py

@@ -50,6 +50,7 @@
     room_keys,
     room_upgrade_rest_servlet,
     sendtodevice,
+    shared_rooms,
     sync,
     tags,
     thirdparty,
@@ -113,6 +114,7 @@ def register_servlets(client_resource, hs):
         devices.register_servlets(hs, client_resource)
         thirdparty.register_servlets(hs, client_resource)
         sendtodevice.register_servlets(hs, client_resource)
+        shared_rooms.register_servlets(hs, client_resource)
         user_directory.register_servlets(hs, client_resource)
         groups.register_servlets(hs, client_resource)
         room_upgrade_rest_servlet.register_servlets(hs, client_resource)

synapse/rest/client/v2_alpha/shared_rooms.py

@@ -0,0 +1,57 @@
+# -*- coding: utf-8 -*-
+# Copyright 2020 Half-Shot
+#
+# 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 logging
+
+from synapse.api.errors import Codes, SynapseError
+from synapse.http.servlet import RestServlet
+
+from ._base import client_patterns
+
+logger = logging.getLogger(__name__)
+
+
+class UserSharedRoomsServlet(RestServlet):
+    """
+    GET /uk.half-shot.msc2666/user/shared_rooms/{user_id} HTTP/1.1
+    """
+
+    PATTERNS = client_patterns(
+        "/uk.half-shot.msc2666/user/shared_rooms/(?P<user_id>[^/]*)",
+        releases=(),  # This is an unstable feature
+    )
+
+    def __init__(self, hs):
+        super(UserSharedRoomsServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.store = hs.get_datastore()
+
+    async def on_GET(self, request, user_id):
+        requester = await self.auth.get_user_by_req(request)
+        if user_id == requester.user.to_string():
+            raise SynapseError(
+                code=400,
+                msg="'user_id' must not be the authenticated user",
+                errcode=Codes.FORBIDDEN,
+            )
+
+        rooms = await self.store.get_shared_rooms_for_users(
+            requester.user.to_string(), user_id
+        )
+
+        return 200, {"joined": rooms}
+
+
+def register_servlets(hs, http_server):
+    UserSharedRoomsServlet(hs).register(http_server)

synapse/rest/client/versions.py

@@ -60,6 +60,8 @@ def on_GET(self, request):
                     "org.matrix.e2e_cross_signing": True,
                     # Implements additional endpoints as described in MSC2432
                     "org.matrix.msc2432": True,
+                    # Implements additional endpoints as described in MSC2666
+                    "uk.half-shot.msc2666": True,
                 },
             },
         )

synapse/storage/databases/main/user_directory.py

@@ -663,6 +663,42 @@ async def get_user_dir_rooms_user_is_in(self, user_id):
         users.update(rows)
         return list(users)
 
+    @cached()
+    async def get_shared_rooms_for_users(self, user_id, other_user_id):
+        """
+        Returns the rooms that a user is in.
+
+        Args:
+            user_id(str): Must be a local user
+
+        Returns:
+            list: user_id
+        """
+        SQL = """
+            SELECT p1.room_id
+            FROM users_in_public_rooms as p1
+            INNER JOIN users_in_public_rooms as p2
+                ON p1.room_id = p2.room_id
+                AND p1.user_id = ?
+                AND p2.user_id = ?
+            UNION
+            SELECT room_id
+            FROM users_who_share_private_rooms
+            WHERE
+                user_id = ?
+                AND other_user_id = ?;
+        """
+        rows = await self.db_pool.execute(
+            "get_shared_rooms_for_users",
+            None,
+            SQL,
+            user_id,
+            other_user_id,
+            user_id,
+            other_user_id,
+        )
+        return list({row[0] for row in rows})
+
     def get_user_directory_stream_pos(self):
         return self.db_pool.simple_select_one_onecol(
             table="user_directory_stream_pos",