Do not include rooms with an unknown room version in a sync response. (#10644)

A user will still see this room if it is in a local cache, but it will
not reappear if clearing the cache and reloading.

tests/handlers/test_sync.py

@@ -12,9 +12,16 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from typing import Optional
+
+from synapse.api.constants import EventTypes, JoinRules
 from synapse.api.errors import Codes, ResourceLimitError
 from synapse.api.filtering import DEFAULT_FILTER_COLLECTION
+from synapse.api.room_versions import RoomVersions
 from synapse.handlers.sync import SyncConfig
+from synapse.rest import admin
+from synapse.rest.client import knock, login, room
+from synapse.server import HomeServer
 from synapse.types import UserID, create_requester
 
 import tests.unittest
@@ -24,8 +31,14 @@ import tests.utils
 class SyncTestCase(tests.unittest.HomeserverTestCase):
     """Tests Sync Handler."""
 
-    def prepare(self, reactor, clock, hs):
-        self.hs = hs
+    servlets = [
+        admin.register_servlets,
+        knock.register_servlets,
+        login.register_servlets,
+        room.register_servlets,
+    ]
+
+    def prepare(self, reactor, clock, hs: HomeServer):
         self.sync_handler = self.hs.get_sync_handler()
         self.store = self.hs.get_datastore()
 
@@ -68,12 +81,124 @@ class SyncTestCase(tests.unittest.HomeserverTestCase):
         )
         self.assertEquals(e.value.errcode, Codes.RESOURCE_LIMIT_EXCEEDED)
 
+    def test_unknown_room_version(self):
+        """
+        A room with an unknown room version should not break sync (and should be excluded).
+        """
+        inviter = self.register_user("creator", "pass", admin=True)
+        inviter_tok = self.login("@creator:test", "pass")
 
-def generate_sync_config(user_id: str) -> SyncConfig:
+        user = self.register_user("user", "pass")
+        tok = self.login("user", "pass")
+
+        # Do an initial sync on a different device.
+        requester = create_requester(user)
+        initial_result = self.get_success(
+            self.sync_handler.wait_for_sync_for_user(
+                requester, sync_config=generate_sync_config(user, device_id="dev")
+            )
+        )
+
+        # Create a room as the user.
+        joined_room = self.helper.create_room_as(user, tok=tok)
+
+        # Invite the user to the room as someone else.
+        invite_room = self.helper.create_room_as(inviter, tok=inviter_tok)
+        self.helper.invite(invite_room, targ=user, tok=inviter_tok)
+
+        knock_room = self.helper.create_room_as(
+            inviter, room_version=RoomVersions.V7.identifier, tok=inviter_tok
+        )
+        self.helper.send_state(
+            knock_room,
+            EventTypes.JoinRules,
+            {"join_rule": JoinRules.KNOCK},
+            tok=inviter_tok,
+        )
+        channel = self.make_request(
+            "POST",
+            "/_matrix/client/r0/knock/%s" % (knock_room,),
+            b"{}",
+            tok,
+        )
+        self.assertEquals(200, channel.code, channel.result)
+
+        # The rooms should appear in the sync response.
+        result = self.get_success(
+            self.sync_handler.wait_for_sync_for_user(
+                requester, sync_config=generate_sync_config(user)
+            )
+        )
+        self.assertIn(joined_room, [r.room_id for r in result.joined])
+        self.assertIn(invite_room, [r.room_id for r in result.invited])
+        self.assertIn(knock_room, [r.room_id for r in result.knocked])
+
+        # Test a incremental sync (by providing a since_token).
+        result = self.get_success(
+            self.sync_handler.wait_for_sync_for_user(
+                requester,
+                sync_config=generate_sync_config(user, device_id="dev"),
+                since_token=initial_result.next_batch,
+            )
+        )
+        self.assertIn(joined_room, [r.room_id for r in result.joined])
+        self.assertIn(invite_room, [r.room_id for r in result.invited])
+        self.assertIn(knock_room, [r.room_id for r in result.knocked])
+
+        # Poke the database and update the room version to an unknown one.
+        for room_id in (joined_room, invite_room, knock_room):
+            self.get_success(
+                self.hs.get_datastores().main.db_pool.simple_update(
+                    "rooms",
+                    keyvalues={"room_id": room_id},
+                    updatevalues={"room_version": "unknown-room-version"},
+                    desc="updated-room-version",
+                )
+            )
+
+        # Blow away caches (supported room versions can only change due to a restart).
+        self.get_success(
+            self.store.get_rooms_for_user_with_stream_ordering.invalidate_all()
+        )
+        self.store._get_event_cache.clear()
+
+        # The rooms should be excluded from the sync response.
+        # Get a new request key.
+        result = self.get_success(
+            self.sync_handler.wait_for_sync_for_user(
+                requester, sync_config=generate_sync_config(user)
+            )
+        )
+        self.assertNotIn(joined_room, [r.room_id for r in result.joined])
+        self.assertNotIn(invite_room, [r.room_id for r in result.invited])
+        self.assertNotIn(knock_room, [r.room_id for r in result.knocked])
+
+        # The rooms should also not be in an incremental sync.
+        result = self.get_success(
+            self.sync_handler.wait_for_sync_for_user(
+                requester,
+                sync_config=generate_sync_config(user, device_id="dev"),
+                since_token=initial_result.next_batch,
+            )
+        )
+        self.assertNotIn(joined_room, [r.room_id for r in result.joined])
+        self.assertNotIn(invite_room, [r.room_id for r in result.invited])
+        self.assertNotIn(knock_room, [r.room_id for r in result.knocked])
+
+
+_request_key = 0
+
+
+def generate_sync_config(
+    user_id: str, device_id: Optional[str] = "device_id"
+) -> SyncConfig:
+    """Generate a sync config (with a unique request key)."""
+    global _request_key
+    _request_key += 1
     return SyncConfig(
-        user=UserID(user_id.split(":")[0][1:], user_id.split(":")[1]),
+        user=UserID.from_string(user_id),
         filter_collection=DEFAULT_FILTER_COLLECTION,
         is_guest=False,
-        request_key="request_key",
-        device_id="device_id",
+        request_key=("request_key", _request_key),
+        device_id=device_id,
     )