Merge pull request #22080 from BerriAI/litellm_vllm_response_fix

Fix None (TypeError: 'NoneType' object is not a mapping)

litellm/utils.py

@@ -4644,11 +4644,12 @@ def add_provider_specific_params_to_optional_params(
             )
             is False
         ):
-            extra_body = passed_params.pop("extra_body", {})
+            extra_body = passed_params.pop("extra_body", None) or {}
             for k in passed_params.keys():
                 if k not in openai_params and passed_params[k] is not None:
                     extra_body[k] = passed_params[k]
-            optional_params.setdefault("extra_body", {})
+            if not isinstance(optional_params.get("extra_body"), dict):
+                optional_params["extra_body"] = {}
             initial_extra_body = {
                 **optional_params["extra_body"],
                 **extra_body,

tests/test_litellm/llms/hosted_vllm/responses/test_hosted_vllm_responses.py

@@ -0,0 +1,103 @@
+"""
+Tests for hosted_vllm responses API support.
+
+Regression test for: https://github.com/BerriAI/litellm/issues
+Bug: client.responses.create() raised TypeError: 'NoneType' object is not a mapping
+when extra_body=None was passed through the responses→completion pipeline for
+hosted_vllm (and any OpenAI-compatible provider using add_provider_specific_params_to_optional_params).
+"""
+
+import json
+import os
+import sys
+from unittest.mock import MagicMock, patch
+
+sys.path.insert(
+    0, os.path.abspath("../../../../..")
+)  # Adds the parent directory to the system path
+
+import litellm
+
+
+def _make_mock_chat_completion_response(content: str = "Hello! I'm doing well.") -> dict:
+    return {
+        "id": "chatcmpl-test123",
+        "object": "chat.completion",
+        "created": 1234567890,
+        "model": "Qwen/Qwen3-8B",
+        "choices": [
+            {
+                "index": 0,
+                "message": {"role": "assistant", "content": content},
+                "finish_reason": "stop",
+            }
+        ],
+        "usage": {"prompt_tokens": 10, "completion_tokens": 20, "total_tokens": 30},
+    }
+
+
+def _make_mock_http_client(response_body: dict) -> MagicMock:
+    mock_client = MagicMock()
+    mock_response = MagicMock()
+    mock_response.status_code = 200
+    mock_response.headers = {"content-type": "application/json"}
+    mock_response.json.return_value = response_body
+    mock_response.text = json.dumps(response_body)
+    mock_client.post.return_value = mock_response
+    return mock_client
+
+
+def test_hosted_vllm_responses_create_with_string_input():
+    """
+    Regression test: responses.create() with string input must not raise
+    TypeError: 'NoneType' object is not a mapping.
+
+    Root cause: extra_body=None was passed explicitly through the
+    responses→completion pipeline. In add_provider_specific_params_to_optional_params(),
+    passed_params.pop("extra_body", {}) returned None (key existed with value None),
+    and **None raised TypeError at dict unpacking.
+
+    Fix: normalize None to {} for both extra_body and optional_params["extra_body"].
+    """
+    mock_client = _make_mock_http_client(
+        _make_mock_chat_completion_response("I'm doing well, thanks!")
+    )
+
+    with patch(
+        "litellm.llms.custom_httpx.llm_http_handler._get_httpx_client",
+        return_value=mock_client,
+    ):
+        response = litellm.responses(
+            model="hosted_vllm/Qwen/Qwen3-8B",
+            input="Hello, how are you?",
+            api_base="https://test-vllm.example.com/v1",
+            api_key="test-key",
+        )
+
+    from litellm.types.llms.openai import ResponsesAPIResponse
+
+    assert response is not None
+    assert isinstance(response, ResponsesAPIResponse)
+    assert len(response.output) > 0
+    output_message = response.output[0]
+    assert output_message.role == "assistant"  # type: ignore[union-attr]
+    assert len(output_message.content) > 0  # type: ignore[union-attr]
+    assert "well" in output_message.content[0].text  # type: ignore[union-attr]
+
+
+def test_hosted_vllm_responses_create_with_explicit_none_extra_body():
+    """
+    Directly verify the fix in add_provider_specific_params_to_optional_params:
+    extra_body=None must not crash when building optional_params.
+    """
+    from litellm.utils import get_optional_params
+
+    # This should not raise TypeError: 'NoneType' object is not a mapping
+    optional_params = get_optional_params(
+        model="Qwen/Qwen3-8B",
+        custom_llm_provider="hosted_vllm",
+        extra_body=None,
+    )
+
+    # extra_body=None should be normalized to an empty dict (or absent)
+    assert optional_params.get("extra_body") is not None or "extra_body" not in optional_params