Remove special casing of `m.room.aliases` events (#7034)

changelog.d/7034.removal

@@ -0,0 +1 @@
+Remove special handling of aliases events from [MSC2260](https://github.com/matrix-org/matrix-doc/pull/2260) added in v1.10.0rc1.

synapse/handlers/room.py

@@ -292,16 +292,6 @@ class RoomCreationHandler(BaseHandler):
             except AuthError as e:
                 logger.warning("Unable to update PLs in old room: %s", e)
 
-        new_pl_content = copy_power_levels_contents(old_room_pl_state.content)
-
-        # pre-msc2260 rooms may not have the right setting for aliases. If no other
-        # value is set, set it now.
-        events_default = new_pl_content.get("events_default", 0)
-        new_pl_content.setdefault("events", {}).setdefault(
-            EventTypes.Aliases, events_default
-        )
-
-        logger.debug("Setting correct PLs in new room to %s", new_pl_content)
         yield self.event_creation_handler.create_and_send_nonmember_event(
             requester,
             {
@@ -309,7 +299,7 @@ class RoomCreationHandler(BaseHandler):
                 "state_key": "",
                 "room_id": new_room_id,
                 "sender": requester.user.to_string(),
-                "content": new_pl_content,
+                "content": old_room_pl_state.content,
             },
             ratelimit=False,
         )
@@ -814,10 +804,6 @@ class RoomCreationHandler(BaseHandler):
                     EventTypes.RoomHistoryVisibility: 100,
                     EventTypes.CanonicalAlias: 50,
                     EventTypes.RoomAvatar: 50,
-                    # MSC2260: Allow everybody to send alias events by default
-                    # This will be reudundant on pre-MSC2260 rooms, since the
-                    # aliases event is special-cased.
-                    EventTypes.Aliases: 0,
                     EventTypes.Tombstone: 100,
                     EventTypes.ServerACL: 100,
                 },

synapse/rest/client/v1/room.py

@@ -189,12 +189,6 @@ class RoomStateEventRestServlet(TransactionRestServlet):
 
         content = parse_json_object_from_request(request)
 
-        if event_type == EventTypes.Aliases:
-            # MSC2260
-            raise SynapseError(
-                400, "Cannot send m.room.aliases events via /rooms/{room_id}/state"
-            )
-
         event_dict = {
             "type": event_type,
             "content": content,
@@ -242,12 +236,6 @@ class RoomSendEventRestServlet(TransactionRestServlet):
         requester = await self.auth.get_user_by_req(request, allow_guest=True)
         content = parse_json_object_from_request(request)
 
-        if event_type == EventTypes.Aliases:
-            # MSC2260
-            raise SynapseError(
-                400, "Cannot send m.room.aliases events via /rooms/{room_id}/send"
-            )
-
         event_dict = {
             "type": event_type,
             "content": content,

tests/rest/admin/test_admin.py

@@ -868,6 +868,13 @@ class RoomTestCase(unittest.HomeserverTestCase):
         self.assertEqual(200, int(channel.result["code"]), msg=channel.result["body"])
 
         # Set this new alias as the canonical alias for this room
+        self.helper.send_state(
+            room_id,
+            "m.room.aliases",
+            {"aliases": [test_alias]},
+            tok=self.admin_user_tok,
+            state_key="test",
+        )
         self.helper.send_state(
             room_id,
             "m.room.canonical_alias",

tests/rest/client/v1/test_directory.py

@@ -51,30 +51,26 @@ class DirectoryTestCase(unittest.HomeserverTestCase):
         self.user = self.register_user("user", "test")
         self.user_tok = self.login("user", "test")
 
-    def test_cannot_set_alias_via_state_event(self):
-        self.ensure_user_joined_room()
-        url = "/_matrix/client/r0/rooms/%s/state/m.room.aliases/%s" % (
-            self.room_id,
-            self.hs.hostname,
-        )
-
-        data = {"aliases": [self.random_alias(5)]}
-        request_data = json.dumps(data)
-
-        request, channel = self.make_request(
-            "PUT", url, request_data, access_token=self.user_tok
-        )
-        self.render(request)
-        self.assertEqual(channel.code, 400, channel.result)
+    def test_state_event_not_in_room(self):
+        self.ensure_user_left_room()
+        self.set_alias_via_state_event(403)
 
     def test_directory_endpoint_not_in_room(self):
         self.ensure_user_left_room()
         self.set_alias_via_directory(403)
 
+    def test_state_event_in_room_too_long(self):
+        self.ensure_user_joined_room()
+        self.set_alias_via_state_event(400, alias_length=256)
+
     def test_directory_in_room_too_long(self):
         self.ensure_user_joined_room()
         self.set_alias_via_directory(400, alias_length=256)
 
+    def test_state_event_in_room(self):
+        self.ensure_user_joined_room()
+        self.set_alias_via_state_event(200)
+
     def test_directory_in_room(self):
         self.ensure_user_joined_room()
         self.set_alias_via_directory(200)
@@ -106,6 +102,21 @@ class DirectoryTestCase(unittest.HomeserverTestCase):
         self.render(request)
         self.assertEqual(channel.code, 200, channel.result)
 
+    def set_alias_via_state_event(self, expected_code, alias_length=5):
+        url = "/_matrix/client/r0/rooms/%s/state/m.room.aliases/%s" % (
+            self.room_id,
+            self.hs.hostname,
+        )
+
+        data = {"aliases": [self.random_alias(alias_length)]}
+        request_data = json.dumps(data)
+
+        request, channel = self.make_request(
+            "PUT", url, request_data, access_token=self.user_tok
+        )
+        self.render(request)
+        self.assertEqual(channel.code, expected_code, channel.result)
+
     def set_alias_via_directory(self, expected_code, alias_length=5):
         url = "/_matrix/client/r0/directory/room/%s" % self.random_alias(alias_length)
         data = {"room_id": self.room_id}