fix(proxy): stop forwarding proxy metadata to OpenAI under preview features

With enable_preview_features on, get_requester_metadata fell back to the full proxy metadata dict whenever the caller's requester_metadata had no string values, so OpenAI received user_api_key_hash, the caller IP and user agent. Return only the caller's requester_metadata when it is present

litellm/utils.py

@@ -11012,9 +11012,7 @@ def get_requester_metadata(metadata: Mapping[str, object]):
 
     requester_metadata: Final = metadata.get("requester_metadata")
     if isinstance(requester_metadata, dict):
-        cleaned_metadata = add_openai_metadata(requester_metadata)
-        if cleaned_metadata:
-            return cleaned_metadata
+        return add_openai_metadata(requester_metadata) or None
 
     cleaned_metadata = add_openai_metadata(metadata)
     if cleaned_metadata:

tests/unit/test_utils_get_optional_params.py

@@ -57,6 +57,20 @@ def test_get_requester_metadata_returns_none_for_empty():
     assert get_requester_metadata(metadata) is None
 
 
+@pytest.mark.parametrize(
+    ("metadata", "expected"),
+    [
+        ({"user_api_key_hash": "h", "requester_metadata": {"headers": {"host": "proxy"}}}, None),
+        ({"user_api_key_hash": "h", "requester_metadata": {"team": "a"}}, {"team": "a"}),
+        ({"team": "a"}, {"team": "a"}),
+    ],
+)
+def test_get_requester_metadata_forwards_only_caller_metadata(
+    metadata: dict[str, object], expected: dict[str, str] | None
+) -> None:
+    assert get_requester_metadata(metadata) == expected
+
+
 @patch("litellm.main.openai_chat_completions.completion")
 def test_requester_metadata_forwarded_to_openai(mock_completion):
     mock_completion.return_value = MagicMock()