✨Supports the import and use of LangChain tools.

Author: Bavichi

backend/mcp_service/langchain/compute_tool.py

@@ -2,10 +2,28 @@
 
 @tool
 def multiply(a: int, b: int) -> int:
-    """Calculate the product of two integers."""
+    """
+    Calculate the product of two integers.
+
+    Args:
+        a (int): The first integer.
+        b (int): The second integer.
+
+    Returns:
+        int: The product of a and b.
+    """
     return a * b
 
 @tool
 def add(a: int, b: int) -> int:
-    """Calculate the sum of two numbers"""
+    """
+    Calculate the sum of two numbers.
+
+    Args:
+        a (int): The first addend.
+        b (int): The second addend.
+
+    Returns:
+        int: The sum of a and b.
+    """
     return a+b

backend/services/tool_configuration_service.py

@@ -141,7 +141,7 @@ def _build_tool_info_from_langchain(obj) -> ToolInfo:
             param_info = {
                 "name": param_name,
                 "type": python_type_to_json_schema(param.annotation),
-                "description": "",  # LangChain doesn’t store per-arg descriptions by default
+                "description": "see tool description",  # LangChain doesn’t store per-arg descriptions by default
                 "optional": param.default is not inspect._empty,
             }
 

test/backend/agents/test_create_agent_info.py

@@ -0,0 +1,173 @@
+import unittest
+import logging
+import sys
+from unittest.mock import AsyncMock, MagicMock, patch, Mock
+import pytest
+
+# 创建一个模块模拟函数
+def mock_module(name):
+    mock = MagicMock()
+    sys.modules[name] = mock
+    return mock
+
+# 模拟主要依赖
+mock_module('nexent.core.utils.observer')
+mock_module('nexent.core.agents.agent_model')
+mock_module('smolagents.agents')
+mock_module('smolagents.utils')
+mock_module('smolagents.tools')
+mock_module('services.remote_mcp_service')
+mock_module('database.remote_mcp_db')
+mock_module('database.client')
+mock_module('utils.config_utils')
+mock_module('utils.prompt_template_utils')
+mock_module('database.agent_db')
+
+# 预先模拟consts.model以避免Pydantic错误
+mock_model = mock_module('consts.model')
+mock_tool_config = MagicMock()
+sys.modules['nexent.core.agents.agent_model'].ToolConfig = mock_tool_config
+
+# 模拟logger
+logger_mock = MagicMock()
+
+
+class MockDiscoverLangchainTools:
+    @staticmethod
+    async def discover_langchain_tools():
+        """模拟discover_langchain_tools函数以便于测试"""
+        return []
+
+
+class TestDiscoverLangchainTools:
+    """测试discover_langchain_tools函数"""
+
+    def setup_method(self):
+        """每个测试方法前的设置"""
+        # 为create_agent_info创建一个模拟模块
+        self.agent_info_mock = MagicMock()
+        # 添加logger
+        self.agent_info_mock.logger = logger_mock
+        # 将模拟模块设置为系统模块
+        sys.modules['backend.agents.create_agent_info'] = self.agent_info_mock
+        
+        # 为discover_langchain_modules创建模拟
+        self.discover_modules_mock = MagicMock()
+        self.agent_info_mock.discover_langchain_modules = self.discover_modules_mock
+
+    @pytest.mark.asyncio
+    async def test_discover_langchain_tools_success(self):
+        """测试成功发现LangChain工具的情况"""
+        # 创建模拟的工具对象
+        mock_tool1 = Mock()
+        mock_tool1.name = "test_tool1"
+        
+        mock_tool2 = Mock()
+        mock_tool2.name = "test_tool2"
+        
+        # 设置discover_langchain_modules的返回值
+        self.discover_modules_mock.return_value = [
+            (mock_tool1, "tool1.py"),
+            (mock_tool2, "tool2.py")
+        ]
+        
+        # 复原discover_langchain_tools函数的实现
+        self.agent_info_mock.discover_langchain_tools = Mock(wraps=async_wrapper(self.agent_info_mock))
+        
+        # 执行函数
+        result = await self.agent_info_mock.discover_langchain_tools()
+        
+        # 验证结果
+        assert len(result) == 2
+        assert result[0] == mock_tool1
+        assert result[1] == mock_tool2
+        assert self.discover_modules_mock.called
+
+    @pytest.mark.asyncio
+    async def test_discover_langchain_tools_empty(self):
+        """测试未发现任何工具的情况"""
+        # 设置discover_langchain_modules返回空列表
+        self.discover_modules_mock.return_value = []
+        
+        # 复原discover_langchain_tools函数的实现
+        self.agent_info_mock.discover_langchain_tools = Mock(wraps=async_wrapper(self.agent_info_mock))
+        
+        # 执行函数
+        result = await self.agent_info_mock.discover_langchain_tools()
+        
+        # 验证结果
+        assert len(result) == 0
+        assert result == []
+        assert self.discover_modules_mock.called
+
+    @pytest.mark.asyncio
+    async def test_discover_langchain_tools_module_exception(self):
+        """测试discover_langchain_modules抛出异常的情况"""
+        # 设置discover_langchain_modules抛出异常
+        self.discover_modules_mock.side_effect = Exception("模块发现错误")
+        
+        # 复原discover_langchain_tools函数的实现
+        self.agent_info_mock.discover_langchain_tools = Mock(wraps=async_wrapper(self.agent_info_mock))
+        
+        # 执行函数 - 应该捕获异常并返回空列表
+        result = await self.agent_info_mock.discover_langchain_tools()
+        
+        # 验证结果
+        assert len(result) == 0
+        assert result == []
+        assert self.discover_modules_mock.called
+
+    @pytest.mark.asyncio
+    async def test_discover_langchain_tools_processing_exception(self):
+        """测试处理单个工具出错的情况"""
+        # 创建一个正常的工具
+        mock_good_tool = Mock()
+        mock_good_tool.name = "good_tool"
+        
+        # 创建一个会引发异常的工具，使用真实类而不是Mock
+        class ErrorTool:
+            @property
+            def name(self):
+                raise Exception("工具处理错误")
+        
+        error_tool = ErrorTool()
+        
+        # 设置discover_langchain_modules的返回值
+        self.discover_modules_mock.return_value = [
+            (mock_good_tool, "good_tool.py"),
+            (error_tool, "error_tool.py")
+        ]
+        
+        # 复原discover_langchain_tools函数的实现
+        self.agent_info_mock.discover_langchain_tools = Mock(wraps=async_wrapper(self.agent_info_mock))
+        
+        # 执行函数 - 应该正确处理一个工具并忽略错误的工具
+        result = await self.agent_info_mock.discover_langchain_tools()
+        
+        # 验证结果
+        assert len(result) == 1
+        assert result[0] == mock_good_tool
+
+
+def async_wrapper(mock):
+    """创建一个简单的异步wrapper来模拟discover_langchain_tools函数的行为"""
+    async def discover_langchain_tools():
+        langchain_tools = []
+        try:
+            discovered_tools = mock.discover_langchain_modules()
+            for obj, filename in discovered_tools:
+                try:
+                    # 先尝试访问name属性 - 如果这里抛出异常，则对象不会被添加
+                    tool_name = obj.name
+                    logger_mock.info(f"Loaded LangChain tool '{tool_name}' from {filename}")
+                    langchain_tools.append(obj)
+                except Exception as e:
+                    logger_mock.error(f"Error processing LangChain tool from {filename}: {e}")
+        except Exception as e:
+            logger_mock.error(f"Unexpected error scanning LangChain tools directory: {e}")
+        return langchain_tools
+    return discover_langchain_tools
+
+
+if __name__ == "__main__":
+    unittest.main()