Remember previous timeline limit

2 files changed, 54 insertions, 20 deletions

diff --git a/synapse/handlers/sliding_sync.py b/synapse/handlers/sliding_sync.py
index e4c438f6c8..d94160c59b 100644
--- a/synapse/handlers/sliding_sync.py
+++ b/synapse/handlers/sliding_sync.py
@@ -697,6 +697,7 @@ class SlidingSyncHandler:
         if has_lists or has_room_subscriptions:
             connection_position = await self.connection_store.record_rooms(
                 sync_config=sync_config,
+                room_configs=relevant_room_map,
                 from_token=from_token,
                 sent_room_ids=relevant_room_map.keys(),
                 # TODO: We need to calculate which rooms have had updates since the `from_token` but were not included in the `sent_room_ids`
@@ -2232,22 +2233,26 @@ class HaveSentRoom:
             contains the last stream token of the last updates we sent down
             the room, i.e. we still need to send everything since then to the
             client.
+        timeline_limit: The timeline limit config for the room, if LIVE or
+            PREVIOUSLY. This is used to track if the client has increased
+            the timeline limit to request more events.
     """
 
     status: HaveSentRoomFlag
     last_token: Optional[RoomStreamToken]
+    timeline_limit: Optional[int]
 
     @staticmethod
-    def live() -> "HaveSentRoom":
-        return HaveSentRoom(HaveSentRoomFlag.LIVE, None)
+    def live(timeline_limit: int) -> "HaveSentRoom":
+        return HaveSentRoom(HaveSentRoomFlag.LIVE, None, timeline_limit)
 
     @staticmethod
-    def previously(last_token: RoomStreamToken) -> "HaveSentRoom":
+    def previously(last_token: RoomStreamToken, timeline_limit: int) -> "HaveSentRoom":
         """Constructor for `PREVIOUSLY` flag."""
-        return HaveSentRoom(HaveSentRoomFlag.PREVIOUSLY, last_token)
+        return HaveSentRoom(HaveSentRoomFlag.PREVIOUSLY, last_token, timeline_limit)
 
 
-HAVE_SENT_ROOM_NEVER = HaveSentRoom(HaveSentRoomFlag.NEVER, None)
+HAVE_SENT_ROOM_NEVER = HaveSentRoom(HaveSentRoomFlag.NEVER, None, None)
 
 
 @attr.s(auto_attribs=True)
@@ -2302,6 +2307,7 @@ class SlidingSyncConnectionStore:
     async def record_rooms(
         self,
         sync_config: SlidingSyncConfig,
+        room_configs: Dict[str, RoomSyncConfig],
         from_token: Optional[SlidingSyncStreamToken],
         *,
         sent_room_ids: StrCollection,
@@ -2343,7 +2349,9 @@ class SlidingSyncConnectionStore:
         have_updated = False
         for room_id in sent_room_ids:
             prev_state = new_room_statuses.get(room_id)
-            new_room_statuses[room_id] = HaveSentRoom.live()
+            new_room_statuses[room_id] = HaveSentRoom.live(
+                room_configs[room_id].timeline_limit
+            )
             if prev_state != new_room_statuses[room_id]:
                 have_updated = True
 
@@ -2361,15 +2369,16 @@ class SlidingSyncConnectionStore:
         # we know that there are no existing entires.
 
         if from_token:
-            new_unsent_state = HaveSentRoom.previously(from_token.stream_token.room_key)
-
             for room_id in unsent_room_ids:
                 prev_state = new_room_statuses.get(room_id)
                 if (
                     prev_state is not None
                     and prev_state.status == HaveSentRoomFlag.LIVE
                 ):
-                    new_room_statuses[room_id] = new_unsent_state
+                    new_room_statuses[room_id] = HaveSentRoom.previously(
+                        from_token.stream_token.room_key,
+                        room_configs[room_id].timeline_limit,
+                    )
                     have_updated = True
 
         if not have_updated:
diff --git a/tests/rest/client/test_sync.py b/tests/rest/client/test_sync.py
index 5abf1041be..8d5fd30fdd 100644
--- a/tests/rest/client/test_sync.py
+++ b/tests/rest/client/test_sync.py
@@ -39,7 +39,8 @@ from synapse.api.constants import (
 )
 from synapse.api.room_versions import RoomVersions
 from synapse.events import EventBase
-from synapse.handlers.sliding_sync import StateValues
+from synapse.handlers.sliding_sync import RoomSyncConfig, StateValues
+from synapse.http.servlet import validate_json_object
 from synapse.rest.client import (
     devices,
     knock,
@@ -53,6 +54,7 @@ from synapse.rest.client import (
 from synapse.server import HomeServer
 from synapse.types import (
     JsonDict,
+    Requester,
     RoomStreamToken,
     SlidingSyncStreamToken,
     StreamKeyType,
@@ -60,6 +62,7 @@ from synapse.types import (
     UserID,
 )
 from synapse.types.handlers import SlidingSyncConfig
+from synapse.types.rest.client import SlidingSyncBody
 from synapse.util import Clock
 from synapse.util.stringutils import random_string
 
@@ -1357,6 +1360,22 @@ class SlidingSyncBase(unittest.HomeserverTestCase):
                 "Expected `notifier.wait_for_events(...)` to be triggered"
             )
 
+    def make_sync_config(
+        self, user: UserID, requester: Requester, content: JsonDict
+    ) -> SlidingSyncConfig:
+        """Helper function to turn a dict sync body to a sync config"""
+        body = validate_json_object(content, SlidingSyncBody)
+
+        sync_config = SlidingSyncConfig(
+            user=user,
+            requester=requester,
+            conn_id=body.conn_id,
+            lists=body.lists,
+            room_subscriptions=body.room_subscriptions,
+            extensions=body.extensions,
+        )
+        return sync_config
+
 
 class SlidingSyncTestCase(SlidingSyncBase):
     """
@@ -4538,7 +4557,6 @@ class SlidingSyncTestCase(SlidingSyncBase):
         self.helper.send(room_id1, "msg", tok=user1_tok)
 
         timeline_limit = 5
-        conn_id = "conn_id"
         sync_body = {
             "lists": {
                 "foo-list": {
@@ -4584,19 +4602,22 @@ class SlidingSyncTestCase(SlidingSyncBase):
         requester = self.get_success(
             self.hs.get_auth().get_user_by_access_token(user1_tok)
         )
-        sync_config = SlidingSyncConfig(
-            user=requester.user,
-            requester=requester,
-            conn_id=conn_id,
+        sync_config = self.make_sync_config(
+            user=requester.user, requester=requester, content=sync_body
         )
 
         parsed_initial_from_token = self.get_success(
             SlidingSyncStreamToken.from_string(self.store, initial_from_token)
         )
+        assert sync_config.lists
+        room_configs = {
+            room_id1: RoomSyncConfig.from_room_config(sync_config.lists["foo-list"])
+        }
         connection_position = self.get_success(
             sliding_sync_handler.connection_store.record_rooms(
                 sync_config,
-                parsed_initial_from_token,
+                room_configs=room_configs,
+                from_token=parsed_initial_from_token,
                 sent_room_ids=[],
                 unsent_room_ids=[room_id1],
             )
@@ -4646,7 +4667,6 @@ class SlidingSyncTestCase(SlidingSyncBase):
 
         self.helper.send(room_id1, "msg", tok=user1_tok)
 
-        conn_id = "conn_id"
         sync_body = {
             "lists": {
                 "foo-list": {
@@ -4693,19 +4713,24 @@ class SlidingSyncTestCase(SlidingSyncBase):
         requester = self.get_success(
             self.hs.get_auth().get_user_by_access_token(user1_tok)
         )
-        sync_config = SlidingSyncConfig(
+        sync_config = self.make_sync_config(
             user=requester.user,
             requester=requester,
-            conn_id=conn_id,
+            content=sync_body,
         )
 
         parsed_initial_from_token = self.get_success(
             SlidingSyncStreamToken.from_string(self.store, initial_from_token)
         )
+        assert sync_config.lists
+        room_configs = {
+            room_id1: RoomSyncConfig.from_room_config(sync_config.lists["foo-list"])
+        }
         connection_position = self.get_success(
             sliding_sync_handler.connection_store.record_rooms(
                 sync_config,
-                parsed_initial_from_token,
+                room_configs=room_configs,
+                from_token=parsed_initial_from_token,
                 sent_room_ids=[],
                 unsent_room_ids=[room_id1],
             )