agent_bot/mcp_api_server.py

import json
import subprocess
import asyncio
import sys
import os
from mcp import ClientSession, StdioServerParameters
from mcp.client.stdio import stdio_client
from pydantic import BaseModel
from typing import Dict, List, Any, Optional
import uvicorn
from fastapi import FastAPI, HTTPException
from fastapi.middleware.cors import CORSMiddleware

class ToolModel(BaseModel):
    name: str
    description: Optional[str] = None
    inputSchema: Optional[Dict] = None

class CallRequest(BaseModel):
    name: str
    arguments: Optional[Dict] = {}


class MCPServerManager:
    def __init__(self, config_file="mcp_config.json"):
        # 从配置文件加载MCP服务配置
        self.mcp_servers = self._load_config(config_file)
        # 缓存每个服务的工具列表
        self._tools_cache = {}
        # 存储活动的会话
        self._active_sessions = {}

    def _load_config(self, config_file):
        """
        从配置文件加载MCP服务配置
        
        Args:
            config_file (str): 配置文件路径
            
        Returns:
            dict: MCP服务配置
        """
        try:
            # 加载配置文件
            with open(config_file, 'r', encoding='utf-8') as f:
                config = json.load(f)
            return config.get("mcpServers", {})
        except Exception as e:
            print(f"加载MCP配置文件时出错: {e}")
            # 返回空配置
            return {}

    async def _test_server_command(self, server_name):
        """
        测试服务器命令是否可用
        
        Args:
            server_name (str): 服务器名称
            
        Returns:
            bool: 命令是否可用
        """
        if server_name not in self.mcp_servers:
            return False

        server_config = self.mcp_servers[server_name]
        
        try:
            # 检查命令是否存在
            process = subprocess.Popen([server_config["command"]] + server_config["args"], 
                                     stdout=subprocess.PIPE, 
                                     stderr=subprocess.PIPE,
                                     shell=(sys.platform == 'win32'))
            # 给进程一点时间启动
            await asyncio.sleep(0.5)
            
            # 检查进程是否仍在运行
            if process.poll() is None:
                # 进程仍在运行，终止它
                process.terminate()
                try:
                    process.wait(timeout=1)
                except subprocess.TimeoutExpired:
                    process.kill()
                return True
            else:
                # 进程已退出，检查返回码
                _, stderr = process.communicate()
                if process.returncode == 0 or process.returncode == 1:
                    # 返回码为0(成功)或1(一般错误)表示命令存在
                    return True
                else:
                    print(f"命令执行失败 {server_name}: {stderr.decode()}")
                    return False
        except FileNotFoundError:
            print(f"命令未找到: {server_config['command']}")
            return False
        except Exception as e:
            print(f"测试命令时出错 {server_name}: {e}")
            return False

    async def call_mcp_server(self, server_name, method, params=None):
        """
        调用指定的MCP服务器
        
        Args:
            server_name (str): 服务器名称
            method (str): 要调用的方法
            params (dict): 方法参数
            
        Returns:
            dict: MCP服务器的响应
        """
        if server_name not in self.mcp_servers:
            return {"error": f"MCP server '{server_name}' not found"}

        # 检查命令是否可用
        if not await self._test_server_command(server_name):
            return {"error": f"MCP server '{server_name}' 命令不可用"}

        try:
            # 创建临时会话（每次调用都创建新会话）
            server_config = self.mcp_servers[server_name]
            
            async with stdio_client(
                StdioServerParameters(
                    command=server_config["command"],
                    args=server_config["args"],
                    env=None
                )
            ) as (read, write):
                async with ClientSession(read, write) as session:
                    # 初始化MCP服务器
                    await session.initialize()
                    
                    # 调用指定方法
                    if method == "prompts/list":
                        result = await session.list_prompts()
                    elif method == "prompts/get" and params:
                        result = await session.get_prompt(params["name"])
                    elif method == "resources/list":
                        result = await session.list_resources()
                    elif method == "resources/read" and params:
                        result = await session.read_resource(params["uri"])
                    elif method == "tools/list":
                        result = await session.list_tools()
                    elif method == "tools/call" and params:
                        result = await session.call_tool(params["name"], params.get("arguments", {}))
                    else:
                        # 通用方法调用
                        result = await session.send_request(method, params or {})
                    
                    # 将结果转换为可序列化的字典
                    return self._serialize_result(result)
        except Exception as e:
            return {"error": f"调用MCP服务时出错: {str(e)}"}

    def _serialize_result(self, result):
        """
        将MCP结果转换为可JSON序列化的格式
        """
        from pydantic import BaseModel
        if isinstance(result, BaseModel):
            return result.model_dump()
        elif isinstance(result, dict):
            return {key: self._serialize_result(value) for key, value in result.items()}
        elif isinstance(result, list):
            return [self._serialize_result(item) for item in result]
        else:
            return result

    async def get_actual_mcp_tools(self, server_name):
        """
        获取指定MCP服务的实际工具列表
        
        Args:
            server_name (str): 服务器名称
            
        Returns:
            list: 实际的工具列表
        """
        if server_name not in self.mcp_servers:
            return []
            
        try:
            result = await self.call_mcp_server(server_name, "tools/list")
            if isinstance(result, dict) and "tools" in result:
                # 缓存工具列表
                self._tools_cache[server_name] = result["tools"]
                return result["tools"]
            return []
        except Exception as e:
            print(f"获取 {server_name} 工具列表时出错: {e}")
            return []

    async def get_all_mcp_tools(self):
        """
        获取所有MCP服务的实际工具列表
        
        Returns:
            list: 所有MCP服务的工具列表，每个工具名称后缀添加_mcp
        """
        all_tools = []
        for server_name in self.mcp_servers.keys():
            try:
                tools = await self.get_actual_mcp_tools(server_name)
                # 为每个工具名称添加_mcp后缀以区分
                for tool in tools:
                    # 创建工具副本并修改名称
                    tool_copy = tool.copy()
                    tool_copy['name'] = f"{tool['name']}_mcp"
                    all_tools.append(tool_copy)
            except Exception as e:
                print(f"获取 {server_name} 工具列表时出错: {e}")
        return all_tools

    async def call_mcp_tool(self, tool_name, arguments):
        """
        执行MCP工具调用
        
        Args:
            tool_name (str): 工具名称（需要以_mcp结尾）
            arguments (dict): 工具参数
            
        Returns:
            dict: 工具执行结果
        """
        try:
            # 验证工具名称格式
            if not tool_name.endswith("_mcp"):
                return {"error": f"无效的工具名称格式: {tool_name}"}
            
            # 移除_mcp后缀获取原始工具名称
            original_tool_name = tool_name[:-4]
            
            # 查找工具所属的服务器
            server_name = self._find_server_for_tool(original_tool_name)
            if not server_name:
                return {"error": f"未找到工具 {tool_name} 对应的MCP服务器"}
            
            # 调用工具
            result = await self.call_mcp_server(
                server_name, 
                "tools/call", 
                {
                    "name": original_tool_name,
                    "arguments": arguments
                }
            )
            
            return result
        except Exception as e:
            return {"error": f"MCP工具调用失败: {str(e)}"}

    def _find_server_for_tool(self, tool_name):
        """
        根据工具名称查找对应的服务器名称
        
        Args:
            tool_name (str): 工具名称
            
        Returns:
            str or None: 服务器名称或None
        """
        # 遍历缓存的工具列表查找对应的服务器
        for server_name, tools in self._tools_cache.items():
            for tool in tools:
                if tool.get("name") == tool_name:
                    return server_name
        return None

    async def initialize_all_servers(self):
        """
        初始化所有MCP服务器并获取工具列表
        """
        print("正在测试MCP服务器连接...")
        for server_name in self.mcp_servers.keys():
            if await self._test_server_command(server_name):
                print(f"✓ {server_name} 命令可用")
            else:
                print(f"✗ {server_name} 命令不可用")



# 创建FastAPI应用
app = FastAPI(title="MCP API Server", description="MCP服务API接口")

# 添加CORS中间件
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# 创建全局MCP服务器管理器实例
mcp_manager = MCPServerManager()


@app.get("/")
async def root():
    return {"message": "MCP API Server is running"}


@app.get("/tools", response_model=List[ToolModel])
async def get_tools():
    """
    获取所有MCP工具列表
    """
    try:
        tools = await mcp_manager.get_all_mcp_tools()
        return tools
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))


@app.post("/call")
async def call_tool(request: CallRequest):
    """
    调用指定的MCP工具
    """
    try:
        result = await mcp_manager.call_mcp_tool(request.name, request.arguments)
        # 检查是否有错误
        if isinstance(result, dict) and "error" in result:
            raise HTTPException(status_code=500, detail=result["error"])
        return result
    except HTTPException:
        raise
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))


if __name__ == "__main__":
    # 初始化所有服务器
    print("正在初始化MCP服务器...")
    loop = asyncio.get_event_loop()
    loop.run_until_complete(mcp_manager.initialize_all_servers())
    print("MCP服务器初始化完成")
    
    # 启动FastAPI服务器
    print("启动MCP API服务器: http://localhost:8000")
    uvicorn.run("mcp_api_server:app", host="localhost", port=8000, reload=False)