"""Tests for serve() function."""
import pytest
from unittest.mock import Mock, patch
from typing import Dict, Any
from mcp_chain.serve import serve
class MockDictMCPServer:
"""Mock DictMCPServer for testing."""
def __init__(self, metadata: Dict[str, Any] = None):
if metadata is None:
self._metadata = {"tools": [], "resources": []}
else:
self._metadata = metadata
def get_metadata(self) -> Dict[str, Any]:
return self._metadata
def handle_request(self, request: Dict[str, Any]) -> Dict[str, Any]:
return {"result": "success"}
def test_serve_function_exists():
"""Test that serve function exists and is callable."""
assert callable(serve)
@patch("mcp_chain.serve.FastMCPServer")
def test_serve_creates_fastmcp_server(mock_fastmcp_server_class):
"""Test that serve() creates a FastMCPServer instance."""
mock_chain = MockDictMCPServer()
mock_server_instance = Mock()
mock_fastmcp_server_class.return_value = mock_server_instance
# Mock the run method to avoid actually starting a server
mock_server_instance.run.return_value = None
serve(mock_chain, name="test-server")
# Should have created FastMCPServer with our chain and name
mock_fastmcp_server_class.assert_called_once_with(mock_chain, name="test-server")
# Should have called run on the server
mock_server_instance.run.assert_called_once()
@patch("mcp_chain.serve.FastMCPServer")
def test_serve_passes_kwargs_to_run(mock_fastmcp_server_class):
"""Test that serve() passes kwargs to FastMCP run method."""
mock_chain = MockDictMCPServer()
mock_server_instance = Mock()
mock_fastmcp_server_class.return_value = mock_server_instance
mock_server_instance.run.return_value = None
# Call serve with additional kwargs
serve(mock_chain, name="test-server", port=8080, transport="http")
# Should pass kwargs to run method
mock_server_instance.run.assert_called_once_with(
name="test-server", port=8080, transport="http"
)
@patch("mcp_chain.serve.FastMCPServer")
def test_serve_with_minimal_args(mock_fastmcp_server_class):
"""Test serve() works with minimal arguments."""
mock_chain = MockDictMCPServer()
mock_server_instance = Mock()
mock_fastmcp_server_class.return_value = mock_server_instance
mock_server_instance.run.return_value = None
# Should work with just a chain
serve(mock_chain)
mock_fastmcp_server_class.assert_called_once_with(mock_chain, name="mcp-chain")
mock_server_instance.run.assert_called_once_with(name="mcp-chain")
def test_serve_validates_chain_is_dict_mcp_server():
"""Test that serve() validates the chain implements DictMCPServer protocol."""
# This should fail if we pass something that's not a DictMCPServer
invalid_chain = "not a server"
with pytest.raises((TypeError, AttributeError)):
serve(invalid_chain)
