Use sanitize deep copy style to replace deepcopy usage

litellm/proxy/guardrails/guardrail_hooks/noma/noma_v2.py

@@ -7,7 +7,6 @@
 import enum
 import json
 import os
-from copy import deepcopy
 from datetime import datetime
 from typing import TYPE_CHECKING, Any, Literal, Optional, Type, cast
 from urllib.parse import urlparse
@@ -131,6 +130,35 @@ class NomaV2Guardrail(CustomGuardrail):
 
         raise ValueError("Noma v2 response missing valid action")
 
+    @staticmethod
+    def _json_safe_copy(data: Any) -> Any:
+        """JSON round-trip producing a deep, JSON-serializable copy of `data`.
+
+        Fast path: `json.dumps` (C-level) with a `default=` callback that
+        handles Pydantic models and falls back to `str(obj)` for anything
+        non-serializable (e.g. uvloop.Loop, locks, other C-extension objects
+        whose __reduce__ raises — which is why this replaces deepcopy).
+
+        Slow path: if `json.dumps` raises (circular refs, etc.), retry with
+        `safe_dumps` which walks the tree in Python with explicit cycle
+        detection. Finally `safe_json_loads` parses back to a Python tree.
+        """
+
+        def _default(obj: Any) -> Any:
+            if hasattr(obj, "model_dump"):
+                try:
+                    return obj.model_dump()
+                except Exception:
+                    pass
+            return str(obj)
+
+        try:
+            json_str = json.dumps(data, default=_default)
+        except (ValueError, TypeError):
+            json_str = safe_dumps(data)
+
+        return safe_json_loads(json_str, default={})
+
     def _build_scan_payload(
         self,
         inputs: GenericGuardrailAPIInputs,
@@ -139,7 +167,12 @@ class NomaV2Guardrail(CustomGuardrail):
         logging_obj: Optional["LiteLLMLoggingObj"],
         application_id: Optional[str],
     ) -> dict:
-        payload_request_data = deepcopy(request_data)
+        # JSON round-trip rather than deepcopy: on post_call / during_call /
+        # during_mcp_call, request_data contains uvloop.Loop and other C-extension
+        # objects whose __reduce__ raises, crashing pickle-based copy.
+        payload_request_data = self._json_safe_copy(request_data)
+        if not isinstance(payload_request_data, dict):
+            payload_request_data = {}
         if logging_obj is not None:
             payload_request_data["litellm_logging_obj"] = getattr(
                 logging_obj, "model_call_details", None
@@ -157,20 +190,8 @@ class NomaV2Guardrail(CustomGuardrail):
 
     @staticmethod
     def _sanitize_payload_for_transport(payload: dict) -> dict:
-        def _default(obj: Any) -> Any:
-            if hasattr(obj, "model_dump"):
-                try:
-                    return obj.model_dump()
-                except Exception:
-                    pass
-            return str(obj)
+        safe_payload = NomaV2Guardrail._json_safe_copy(payload)
 
-        try:
-            json_str = json.dumps(payload, default=_default)
-        except (ValueError, TypeError):
-            json_str = safe_dumps(payload)
-
-        safe_payload = safe_json_loads(json_str, default={})
         if safe_payload == {} and payload:
             verbose_proxy_logger.warning(
                 "Noma v2 guardrail: payload serialization failed, falling back to empty payload"