Track notification counts per thread (implement MSC3773). (#13776)

When retrieving counts of notifications segment the results based on the
thread ID, but choose whether to return them as individual threads or as
a single summed field by letting the client opt-in via a sync flag.

The summarization code is also updated to be per thread, instead of per
room.

1 files changed, 35 insertions, 5 deletions

diff --git a/synapse/handlers/sync.py b/synapse/handlers/sync.py

index 4abb9b6127..329e89c604 100644
--- a/synapse/handlers/sync.py
+++ b/synapse/handlers/sync.py
@@ -40,7 +40,7 @@ from synapse.handlers.relations import BundledAggregations
 from synapse.logging.context import current_context
 from synapse.logging.opentracing import SynapseTags, log_kv, set_tag, start_active_span
 from synapse.push.clientformat import format_push_rules_for_user
-from synapse.storage.databases.main.event_push_actions import NotifCounts
+from synapse.storage.databases.main.event_push_actions import RoomNotifCounts
 from synapse.storage.roommember import MemberSummary
 from synapse.storage.state import StateFilter
 from synapse.types import (
@@ -128,6 +128,7 @@ class JoinedSyncResult:
     ephemeral: List[JsonDict]
     account_data: List[JsonDict]
     unread_notifications: JsonDict
+    unread_thread_notifications: JsonDict
     summary: Optional[JsonDict]
     unread_count: int
 
@@ -278,6 +279,8 @@ class SyncHandler:
 
         self.rooms_to_exclude = hs.config.server.rooms_to_exclude_from_sync
 
+        self._msc3773_enabled = hs.config.experimental.msc3773_enabled
+
     async def wait_for_sync_for_user(
         self,
         requester: Requester,
@@ -1288,7 +1291,7 @@ class SyncHandler:
 
     async def unread_notifs_for_room_id(
         self, room_id: str, sync_config: SyncConfig
-    ) -> NotifCounts:
+    ) -> RoomNotifCounts:
         with Measure(self.clock, "unread_notifs_for_room_id"):
 
             return await self.store.get_unread_event_push_actions_by_room_for_user(
@@ -2353,6 +2356,7 @@ class SyncHandler:
                     ephemeral=ephemeral,
                     account_data=account_data_events,
                     unread_notifications=unread_notifications,
+                    unread_thread_notifications={},
                     summary=summary,
                     unread_count=0,
                 )
@@ -2360,10 +2364,36 @@ class SyncHandler:
                 if room_sync or always_include:
                     notifs = await self.unread_notifs_for_room_id(room_id, sync_config)
 
-                    unread_notifications["notification_count"] = notifs.notify_count
-                    unread_notifications["highlight_count"] = notifs.highlight_count
+                    # Notifications for the main timeline.
+                    notify_count = notifs.main_timeline.notify_count
+                    highlight_count = notifs.main_timeline.highlight_count
+                    unread_count = notifs.main_timeline.unread_count
 
-                    room_sync.unread_count = notifs.unread_count
+                    # Check the sync configuration.
+                    if (
+                        self._msc3773_enabled
+                        and sync_config.filter_collection.unread_thread_notifications()
+                    ):
+                        # And add info for each thread.
+                        room_sync.unread_thread_notifications = {
+                            thread_id: {
+                                "notification_count": thread_notifs.notify_count,
+                                "highlight_count": thread_notifs.highlight_count,
+                            }
+                            for thread_id, thread_notifs in notifs.threads.items()
+                            if thread_id is not None
+                        }
+
+                    else:
+                        # Combine the unread counts for all threads and main timeline.
+                        for thread_notifs in notifs.threads.values():
+                            notify_count += thread_notifs.notify_count
+                            highlight_count += thread_notifs.highlight_count
+                            unread_count += thread_notifs.unread_count
+
+                    unread_notifications["notification_count"] = notify_count
+                    unread_notifications["highlight_count"] = highlight_count
+                    room_sync.unread_count = unread_count
 
                     sync_result_builder.joined.append(room_sync)