fix(backend): address review findings for pending-message endpoint

- Fix off-by-one in rate limit: use >= instead of > for call count check
- Move track_user_message() after push_pending_message() so analytics
  only fires on successful push
- Add logger.warning in rate-limiter except-Exception catch instead of
  silent pass
- Use fullmatch instead of match for UUID regex validation
- Add extra="forbid" to PendingMessageContext to reject unexpected fields

autogpt_platform/backend/backend/api/features/chat/routes.py

@@ -133,7 +133,7 @@ async def _resolve_workspace_files(
     Used by both the stream and pending-message endpoints to prevent callers from
     referencing other users' files.
     """
-    valid_ids = [fid for fid in file_ids if _UUID_RE.match(fid)]
+    valid_ids = [fid for fid in file_ids if _UUID_RE.fullmatch(fid)]
     if not valid_ids:
         return []
     workspace = await get_or_create_workspace(user_id)
@@ -1172,7 +1172,7 @@ async def queue_pending_message(
                 ),
             )
         )
-        if _call_count > _PENDING_CALL_LIMIT:
+        if _call_count >= _PENDING_CALL_LIMIT:
             raise HTTPException(
                 status_code=429,
                 detail=f"Too many pending messages: limit is {_PENDING_CALL_LIMIT} per {_PENDING_CALL_WINDOW_SECONDS}s",
@@ -1180,20 +1180,14 @@ async def queue_pending_message(
     except HTTPException:
         raise
     except Exception:
-        pass  # Redis failure is non-fatal; fail open
-
-    track_user_message(
-        user_id=user_id,
-        session_id=session_id,
-        message_length=len(request.message),
-    )
+        logger.warning("queue_pending_message: rate-limit check failed, failing open")  # non-fatal
 
     # Sanitise file IDs to the user's own workspace so injection doesn't
     # surface other users' files.  _resolve_workspace_files handles UUID
     # filtering and the workspace-scoped DB lookup.
     sanitized_file_ids: list[str] = []
     if request.file_ids:
-        valid_id_count = sum(1 for fid in request.file_ids if _UUID_RE.match(fid))
+        valid_id_count = sum(1 for fid in request.file_ids if _UUID_RE.fullmatch(fid))
         files = await _resolve_workspace_files(user_id, request.file_ids)
         sanitized_file_ids = [wf.id for wf in files]
         if len(sanitized_file_ids) != valid_id_count:
@@ -1220,6 +1214,12 @@ async def queue_pending_message(
     )
     buffer_length = await push_pending_message(session_id, pending)
 
+    track_user_message(
+        user_id=user_id,
+        session_id=session_id,
+        message_length=len(request.message),
+    )
+
     # Check whether a turn is currently running for UX feedback.
     active_session = await stream_registry.get_session(session_id)
     turn_in_flight = bool(active_session and active_session.status == "running")

autogpt_platform/backend/backend/copilot/pending_messages.py

@@ -49,7 +49,7 @@ _PENDING_TTL_SECONDS = 3600  # 1 hour — matches stream_ttl default
 _NOTIFY_PAYLOAD = "1"
 
 
-class PendingMessageContext(BaseModel):
+class PendingMessageContext(BaseModel, extra="forbid"):
     """Structured page context attached to a pending message."""
 
     url: str | None = None