feat(guardrails): Flag for PII Masking on Logging

Fixes https://github.com/BerriAI/litellm/issues/4580

litellm/tests/test_guardrails_config.py

@@ -0,0 +1,73 @@
+# What is this?
+## Unit Tests for guardrails config
+import asyncio
+import inspect
+import os
+import sys
+import time
+import traceback
+import uuid
+from datetime import datetime
+
+import pytest
+from pydantic import BaseModel
+
+import litellm.litellm_core_utils
+import litellm.litellm_core_utils.litellm_logging
+
+sys.path.insert(0, os.path.abspath("../.."))
+from typing import Any, List, Literal, Optional, Tuple, Union
+from unittest.mock import AsyncMock, MagicMock, patch
+
+import litellm
+from litellm import Cache, completion, embedding
+from litellm.integrations.custom_logger import CustomLogger
+from litellm.types.utils import LiteLLMCommonStrings
+
+
+class CustomLoggingIntegration(CustomLogger):
+    def __init__(self) -> None:
+        super().__init__()
+
+    def logging_hook(
+        self, kwargs: dict, result: Any, call_type: str
+    ) -> Tuple[dict, Any]:
+        input: Optional[Any] = kwargs.get("input", None)
+        messages: Optional[List] = kwargs.get("messages", None)
+        if call_type == "completion":
+            # assume input is of type messages
+            if input is not None and isinstance(input, list):
+                input[0]["content"] = "Hey, my name is [NAME]."
+            if messages is not None and isinstance(messages, List):
+                messages[0]["content"] = "Hey, my name is [NAME]."
+
+            kwargs["input"] = input
+            kwargs["messages"] = messages
+        return kwargs, result
+
+
+def test_guardrail_masking_logging_only():
+    """
+    Assert response is unmasked.
+
+    Assert logged response is masked.
+    """
+    callback = CustomLoggingIntegration()
+
+    with patch.object(callback, "log_success_event", new=MagicMock()) as mock_call:
+        litellm.callbacks = [callback]
+        messages = [{"role": "user", "content": "Hey, my name is Peter."}]
+        response = completion(
+            model="gpt-3.5-turbo", messages=messages, mock_response="Hi Peter!"
+        )
+
+        assert response.choices[0].message.content == "Hi Peter!"  # type: ignore
+
+        mock_call.assert_called_once()
+
+        print(mock_call.call_args.kwargs["kwargs"]["messages"][0]["content"])
+
+        assert (
+            mock_call.call_args.kwargs["kwargs"]["messages"][0]["content"]
+            == "Hey, my name is [NAME]."
+        )