Fix linter errors

synapse/handlers/relations.py

@@ -598,7 +598,7 @@ class RelationsHandler:
 
     async def fetch_thread_roots_and_aggregations(
         self,
-        thread_ids: Iterable[str],
+        thread_ids: Collection[str],
         user_id: str,
     ) -> tuple[ThreadRootsMap, AggregationsMap]:
         """Fetch thread root events and their bundled aggregations.

synapse/handlers/sliding_sync/extensions.py

@@ -36,6 +36,10 @@ from synapse.api.constants import (
 )
 from synapse.events import EventBase
 from synapse.handlers.receipts import ReceiptEventSource
+from synapse.handlers.relations import (
+    AggregationsMap,
+    ThreadRootsMap,
+)
 from synapse.handlers.sliding_sync.room_lists import RoomsForUserType
 from synapse.logging.opentracing import trace
 from synapse.storage.databases.main.receipts import ReceiptInRoom
@@ -1209,8 +1213,8 @@ class SlidingSyncExtensionHandler:
         # the latest event for each thread.
 
         # Optionally fetch thread root events and their bundled aggregations
-        thread_root_event_map = {}
-        aggregations_map = {}
+        thread_root_event_map: ThreadRootsMap = {}
+        aggregations_map: AggregationsMap = {}
         if threads_request.include_roots:
             (
                 thread_root_event_map,

synapse/rest/client/relations.py

@@ -25,12 +25,18 @@ from typing import TYPE_CHECKING
 from synapse.api.constants import Direction
 from synapse.api.errors import SynapseError
 from synapse.events.utils import SerializeEventConfig
-from synapse.handlers.relations import BundledAggregations, ThreadsListInclude
+from synapse.handlers.relations import ThreadsListInclude
 from synapse.http.server import HttpServer
-from synapse.http.servlet import RestServlet, parse_boolean, parse_integer, parse_string
+from synapse.http.servlet import (
+    RestServlet,
+    parse_and_validate_json_object_from_request,
+    parse_boolean,
+    parse_integer,
+    parse_string,
+)
 from synapse.http.site import SynapseRequest
 from synapse.rest.client._base import client_patterns
-from synapse.storage.databases.main.relations import ThreadsNextBatch, ThreadUpdateInfo
+from synapse.storage.databases.main.relations import ThreadsNextBatch
 from synapse.streams.config import (
     PaginationConfig,
     extract_stream_token_from_pagination_token,
@@ -163,67 +169,11 @@ class ThreadUpdatesServlet(RestServlet):
         # TODO: Get sliding sync handler for filter_rooms logic
         # self.sliding_sync_handler = hs.get_sliding_sync_handler()
 
-    async def _serialize_thread_updates(
-        self,
-        thread_updates: list[ThreadUpdateInfo],
-        bundled_aggregations: dict[str, BundledAggregations],
-        time_now: int,
-        serialize_options: SerializeEventConfig,
-    ) -> dict[str, dict[str, JsonDict]]:
-        """
-        Serialize thread updates into the response format.
-
-        Args:
-            thread_updates: List of thread update info from storage
-            bundled_aggregations: Map of event_id to bundled aggregations
-            time_now: Current time in milliseconds
-            serialize_options: Serialization configuration
-
-        Returns:
-            Nested dict mapping room_id -> thread_root_id -> thread update dict
-        """
-        chunk: dict[str, dict[str, JsonDict]] = {}
-
-        for update in thread_updates:
-            room_id = update.room_id
-            thread_id = update.thread_id
-
-            if room_id not in chunk:
-                chunk[room_id] = {}
-
-            update_dict: JsonDict = {}
-
-            # Serialize thread root if present
-            if update.thread_root_event is not None:
-                bundle_aggs_map = (
-                    {thread_id: bundled_aggregations[thread_id]}
-                    if thread_id in bundled_aggregations
-                    else None
-                )
-                serialized_events = await self.event_serializer.serialize_events(
-                    [update.thread_root_event],
-                    time_now,
-                    config=serialize_options,
-                    bundle_aggregations=bundle_aggs_map,
-                )
-                if serialized_events:
-                    update_dict["thread_root"] = serialized_events[0]
-
-            # Add per-thread prev_batch if present
-            if update.prev_batch is not None:
-                update_dict["prev_batch"] = await update.prev_batch.to_string(
-                    self.store
-                )
-
-            chunk[room_id][thread_id] = update_dict
-
-        return chunk
-
     async def on_POST(self, request: SynapseRequest) -> tuple[int, JsonDict]:
         requester = await self.auth.get_user_by_req(request)
 
         # Parse request body
-        body = ThreadUpdatesBody.model_validate_json(request.content.read())
+        body = parse_and_validate_json_object_from_request(request, ThreadUpdatesBody)
 
         # Parse query parameters
         dir_str = parse_string(request, "dir", default="b")