Files
litellm/tests/test_litellm/responses/test_responses_api_bridge_flag.py
T
Sameer Kankute 2506ccb2bc refactor(responses): drop use_responses_api_bridge; fix PLR0915
- Only use_chat_completions_api and openai/chat_completions/ opt into the bridge
- Extract MCP gateway and file_search emulation dispatch to cut responses() size
- Update docs and tests

Made-with: Cursor
2026-04-13 18:22:17 +05:30

283 lines
11 KiB
Python

"""
Tests for forcing the /responses → /chat/completions bridge for `openai/` models
(via `use_chat_completions_api` or the `openai/chat_completions/<model>` model id).
Includes file_search emulation: the flag must be forwarded on inner aresponses
calls so routed requests do not hit a custom api_base /v1/responses endpoint.
"""
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
from litellm.types.llms.openai import ResponseAPIUsage, ResponsesAPIResponse
class TestUseResponsesApiBridgeFlag:
"""Test that bridge opt-in forces the chat completions path."""
@patch(
"litellm.responses.main.litellm_completion_transformation_handler.response_api_handler"
)
@patch(
"litellm.responses.main.ProviderConfigManager.get_provider_responses_api_config"
)
def test_bridge_used_when_use_chat_completions_api_true(
self, mock_get_config, mock_bridge_handler
):
"""When use_chat_completions_api=True, the bridge handler should be called."""
mock_get_config.return_value = litellm.OpenAIResponsesAPIConfig()
mock_bridge_handler.return_value = MagicMock()
litellm.responses(
model="openai/my-custom-model",
input="Hello",
use_chat_completions_api=True,
litellm_logging_obj=MagicMock(),
)
mock_bridge_handler.assert_called_once()
@patch(
"litellm.responses.main.litellm_completion_transformation_handler.response_api_handler"
)
@patch(
"litellm.responses.main.ProviderConfigManager.get_provider_responses_api_config"
)
def test_bridge_used_when_model_uses_chat_completions_prefix(
self, mock_get_config, mock_bridge_handler
):
"""`openai/chat_completions/<name>` normalizes to `openai/<name>` and uses the bridge."""
mock_get_config.return_value = litellm.OpenAIResponsesAPIConfig()
mock_bridge_handler.return_value = MagicMock()
litellm.responses(
model="openai/chat_completions/my-custom-model",
input="Hello",
litellm_logging_obj=MagicMock(),
)
mock_bridge_handler.assert_called_once()
# Model string is provider-normalized after resolution; prefix only forces the bridge.
assert mock_bridge_handler.call_args.kwargs["model"].endswith("my-custom-model")
@patch("litellm.responses.main.base_llm_http_handler.response_api_handler")
@patch(
"litellm.responses.main.ProviderConfigManager.get_provider_responses_api_config"
)
def test_native_forwarding_when_flag_absent(
self, mock_get_config, mock_native_handler
):
"""When use_chat_completions_api is not set, openai/ models should use
native responses API forwarding (existing behavior)."""
mock_get_config.return_value = litellm.OpenAIResponsesAPIConfig()
mock_native_handler.return_value = MagicMock()
litellm.responses(
model="openai/gpt-4o",
input="Hello",
litellm_logging_obj=MagicMock(),
)
mock_native_handler.assert_called_once()
@patch(
"litellm.responses.main.litellm_completion_transformation_handler.response_api_handler"
)
@patch(
"litellm.responses.main.ProviderConfigManager.get_provider_responses_api_config"
)
def test_flag_does_not_leak_into_kwargs(self, mock_get_config, mock_bridge_handler):
"""use_chat_completions_api should be popped and not passed to the bridge handler."""
mock_get_config.return_value = litellm.OpenAIResponsesAPIConfig()
mock_bridge_handler.return_value = MagicMock()
litellm.responses(
model="openai/my-custom-model",
input="Hello",
use_chat_completions_api=True,
litellm_logging_obj=MagicMock(),
)
call_kwargs = mock_bridge_handler.call_args
all_kwargs = call_kwargs.kwargs if call_kwargs.kwargs else {}
assert "use_chat_completions_api" not in all_kwargs
@patch(
"litellm.responses.main.litellm_completion_transformation_handler.response_api_handler"
)
@patch(
"litellm.responses.main.ProviderConfigManager.get_provider_responses_api_config"
)
def test_bridge_used_when_provider_config_none(
self, mock_get_config, mock_bridge_handler
):
"""When the provider has no native responses API config (returns None),
the bridge should be used regardless of the flag (existing behavior)."""
mock_get_config.return_value = None
mock_bridge_handler.return_value = MagicMock()
litellm.responses(
model="anthropic/claude-3-haiku",
input="Hello",
litellm_logging_obj=MagicMock(),
)
mock_bridge_handler.assert_called_once()
@patch("litellm.responses.file_search.emulated_handler._call_aresponses")
@patch(
"litellm.responses.main.ProviderConfigManager.get_provider_responses_api_config"
)
async def test_bridge_flag_forwarded_to_file_search_emulation(
self, mock_get_config, mock_call_aresponses
):
"""When use_chat_completions_api=True and file_search tool is present,
the flag should be forwarded to the inner aresponses call in the
file_search emulation path."""
# Setup: provider has native responses API support
mock_get_config.return_value = litellm.OpenAIResponsesAPIConfig()
# Mock the inner aresponses call to return a valid response
mock_response = ResponsesAPIResponse(
id="resp_123",
model="openai/my-custom-model",
created_at=1234567890,
output=[
{"type": "message", "content": [{"type": "text", "text": "Answer"}]}
],
usage=ResponseAPIUsage(
input_tokens=10, output_tokens=5, total_tokens=15
),
)
mock_call_aresponses.return_value = mock_response
await litellm.aresponses(
model="openai/my-custom-model",
input="Search for information",
tools=[{"type": "file_search"}],
use_chat_completions_api=True,
litellm_logging_obj=MagicMock(),
)
# Verify _call_aresponses was called with use_chat_completions_api=True
mock_call_aresponses.assert_called_once()
call_kwargs = mock_call_aresponses.call_args.kwargs
assert (
call_kwargs.get("use_chat_completions_api") is True
), "use_chat_completions_api should be forwarded to inner aresponses call"
@patch(
"litellm.responses.main.litellm_completion_transformation_handler.response_api_handler"
)
@patch("litellm.vector_stores.main.asearch")
@patch(
"litellm.responses.main.ProviderConfigManager.get_provider_responses_api_config"
)
async def test_bridge_flag_prevents_native_responses_endpoint_call(
self, mock_get_config, mock_asearch, mock_bridge_handler
):
"""
Concrete failing scenario: native OpenAI responses config + bridge flag +
file_search → emulation must still route inner calls through the bridge
(chat completions), not POST to api_base /v1/responses.
"""
mock_get_config.return_value = litellm.OpenAIResponsesAPIConfig()
mock_asearch.return_value = []
first_response = ResponsesAPIResponse(
id="resp_first",
model="openai/my-local-model",
created_at=1234567890,
output=[
{
"type": "function_call",
"name": "litellm_file_search",
"call_id": "call_123",
"arguments": '{"queries": ["test query"]}',
}
],
usage=ResponseAPIUsage(
input_tokens=10, output_tokens=5, total_tokens=15
),
)
second_response = ResponsesAPIResponse(
id="resp_second",
model="openai/my-local-model",
created_at=1234567891,
output=[
{
"type": "message",
"content": [{"type": "text", "text": "Final answer"}],
}
],
usage=ResponseAPIUsage(
input_tokens=20, output_tokens=10, total_tokens=30
),
)
mock_bridge_handler.side_effect = [first_response, second_response]
result = await litellm.aresponses(
model="openai/my-local-model",
input="Search for information",
tools=[
{
"type": "file_search",
"file_search": {"vector_store_ids": ["vs_123"]},
}
],
use_chat_completions_api=True,
api_base="http://localhost:8080/v1",
litellm_logging_obj=MagicMock(),
)
assert mock_bridge_handler.call_count == 2, (
"Bridge handler should be called twice: initial function-tool call "
"and follow-up with tool results"
)
for call in mock_bridge_handler.call_args_list:
all_kwargs = call.kwargs if call.kwargs else {}
assert "use_chat_completions_api" not in all_kwargs
assert result is not None
assert result.id is not None
@patch("litellm.responses.main.base_llm_http_handler.response_api_handler")
@patch("litellm.vector_stores.main.asearch")
@patch(
"litellm.responses.main.ProviderConfigManager.get_provider_responses_api_config"
)
async def test_without_bridge_flag_uses_native_endpoint(
self, mock_get_config, mock_asearch, mock_native_handler
):
"""Without the bridge flag, openai/ with native config uses the native handler."""
mock_get_config.return_value = litellm.OpenAIResponsesAPIConfig()
mock_asearch.return_value = []
mock_native_handler.return_value = ResponsesAPIResponse(
id="resp_native",
model="openai/gpt-4o",
created_at=1234567890,
output=[
{
"type": "message",
"content": [{"type": "text", "text": "Native response"}],
}
],
usage=ResponseAPIUsage(
input_tokens=10, output_tokens=5, total_tokens=15
),
)
result = await litellm.aresponses(
model="openai/gpt-4o",
input="Hello",
litellm_logging_obj=MagicMock(),
)
mock_native_handler.assert_called_once()
assert result is not None