Include the ts the notif was received at

synapse/rest/client/v2_alpha/notifications.py

@@ -68,6 +68,7 @@ class NotificationsServlet(RestServlet):
                 "room_id": pa["room_id"],
                 "profile_tag": pa["profile_tag"],
                 "actions": pa["actions"],
+                "ts": pa["received_ts"],
                 "event": serialize_event(
                     notif_events[pa["event_id"]],
                     self.clock.time_msec(),

synapse/storage/event_push_actions.py

@@ -201,11 +201,13 @@ class EventPushActionsStore(SQLBaseStore):
             else:
                 args = [user_id, limit]
             sql = (
-                "SELECT event_id, room_id, stream_ordering, topological_ordering,"
-                " actions, profile_tag"
-                " FROM event_push_actions"
-                " WHERE user_id = ? %s"
-                " ORDER BY stream_ordering DESC"
+                "SELECT epa.event_id, epa.room_id,"
+                " epa.stream_ordering, epa.topological_ordering,"
+                " epa.actions, epa.profile_tag, e.received_ts"
+                " FROM event_push_actions epa, events e"
+                " WHERE epa.room_id = e.room_id AND epa.event_id = e.event_id"
+                " AND epa.user_id = ? %s"
+                " ORDER BY epa.stream_ordering DESC"
                 " LIMIT ?"
                 % (before_clause,)
             )