Files
2026-07-13 12:39:17 +08:00

86 lines
2.8 KiB
Python

import builtins
import sys
from unittest.mock import MagicMock, patch
import httpx
import pytest
from agents import Agent
from agents.exceptions import UserError
from agents.mcp.server import MCPServerStreamableHttp, _MCPServerWithClientSession
from agents.run_context import RunContextWrapper
# Handle Python version compatibility for ExceptionGroups
if sys.version_info < (3, 11):
from exceptiongroup import BaseExceptionGroup
else:
BaseExceptionGroup = builtins.BaseExceptionGroup
class CrashingClientSessionServer(_MCPServerWithClientSession):
def __init__(self):
super().__init__(cache_tools_list=False, client_session_timeout_seconds=5)
self.cleanup_called = False
def create_streams(self):
raise ValueError("Crash!")
async def cleanup(self):
self.cleanup_called = True
await super().cleanup()
@property
def name(self) -> str:
return "crashing_client_session_server"
@pytest.mark.asyncio
async def test_server_errors_cause_error_and_cleanup_called():
server = CrashingClientSessionServer()
with pytest.raises(ValueError):
await server.connect()
assert server.cleanup_called
@pytest.mark.asyncio
async def test_not_calling_connect_causes_error():
server = CrashingClientSessionServer()
run_context = RunContextWrapper(context=None)
agent = Agent(name="test_agent", instructions="Test agent")
with pytest.raises(UserError):
await server.list_tools(run_context, agent)
with pytest.raises(UserError):
await server.call_tool("foo", {})
@pytest.mark.asyncio
async def test_call_tool_nested_exception_group_mapping():
"""
Regression test ensuring that nested ExceptionGroups containing HTTP errors
are recursively extracted and mapped to a UserError in call_tool().
"""
# 1. Initialize the server with mock streamable parameters
server = MCPServerStreamableHttp(params={"url": "http://fake-mcp-server"})
# 2. Simulate an active connection by mocking the session object
server.session = MagicMock()
# 3. Construct a nested ExceptionGroup hierarchy containing a connection error
http_error = httpx.ConnectError("Network unreachable")
inner_group = BaseExceptionGroup("inner_failures", [http_error])
outer_group = BaseExceptionGroup("outer_failures", [inner_group])
# 4 & 5. Mock the internal retry handler to raise the nested group, and assert UserError
with patch.object(server, "_call_tool_with_isolated_retry", side_effect=outer_group):
with pytest.raises(UserError) as exc_info:
await server.call_tool(tool_name="test_tool", arguments={})
# 6. Verify that the user-facing message is mapped correctly based on the root cause
assert "Connection lost" in str(exc_info.value)
assert exc_info.value.__cause__ is http_error