fix:1.优化mcp插件功能,改用mcp sdk库

This commit is contained in:
xiamuceer
2025-11-08 12:32:32 +08:00
parent 88115a45c5
commit c7c1c1fdf3
9 changed files with 1278 additions and 660 deletions
+185 -197
View File
@@ -1,8 +1,13 @@
"""HTTP MCP客户端 - 实现JSON-RPC 2.0协议"""
import httpx
"""HTTP MCP客户端 - 使用官方 MCP Python SDK 实现"""
import asyncio
from typing import Dict, Any, List, Optional
from contextlib import asynccontextmanager
from mcp import ClientSession, types
from mcp.client.streamable_http import streamablehttp_client
from pydantic import AnyUrl
from app.logger import get_logger
import time
logger = get_logger(__name__)
@@ -13,15 +18,14 @@ class MCPError(Exception):
class HTTPMCPClient:
"""HTTP模式MCP客户端(类似Cursor/Claude Code实现"""
"""HTTP模式MCP客户端(基于官方 MCP Python SDK"""
def __init__(
self,
url: str,
headers: Optional[Dict[str, str]] = None,
env: Optional[Dict[str, str]] = None,
timeout: float = 60.0,
http_client: Optional[httpx.AsyncClient] = None
timeout: float = 60.0
):
"""
初始化HTTP MCP客户端
@@ -31,162 +35,79 @@ class HTTPMCPClient:
headers: HTTP请求头
env: 环境变量(用于API Key等)
timeout: 超时时间(秒)
http_client: 可选的共享HTTP客户端(用于连接池复用)
"""
self.url = url.rstrip('/')
self.headers = headers or {}
self.env = env or {}
self.timeout = timeout
# 设置MCP必需的Accept头
# MCP服务器要求客户端必须接受 application/json 和 text/event-stream
if 'Accept' not in self.headers:
self.headers['Accept'] = 'application/json, text/event-stream'
# 设置Content-Type
if 'Content-Type' not in self.headers:
self.headers['Content-Type'] = 'application/json'
# 如果env中有API Key,添加到headers
if 'API_KEY' in self.env:
self.headers['Authorization'] = f'Bearer {self.env["API_KEY"]}'
# 使用共享客户端或创建新客户端
self._owns_client = http_client is None
if http_client:
self.client = http_client
else:
self.client = httpx.AsyncClient(
timeout=httpx.Timeout(timeout),
headers=self.headers
)
self._request_id = 0
self._session: Optional[ClientSession] = None
self._context_stack = [] # 保存上下文管理器栈
self._initialized = False
self._lock = asyncio.Lock()
def _next_request_id(self) -> int:
"""获取下一个请求ID"""
self._request_id += 1
return self._request_id
async def _call_jsonrpc(
self,
method: str,
params: Optional[Dict[str, Any]] = None
) -> Dict[str, Any]:
"""
调用JSON-RPC 2.0方法
Args:
method: 方法名
params: 参数
Returns:
响应结果
Raises:
MCPError: 调用失败时抛出
"""
request_id = self._next_request_id()
payload = {
"jsonrpc": "2.0",
"id": request_id,
"method": method,
"params": params or {}
}
try:
logger.debug(f"MCP请求: {method} -> {self.url}")
response = await self.client.post(
self.url,
json=payload,
headers=self.headers # 显式传递headers(对于共享客户端很重要)
)
response.raise_for_status()
# 获取响应内容
response_text = response.text
content_type = response.headers.get('content-type', '')
# 如果是空响应
if not response_text or response_text.strip() == '':
raise MCPError("服务器返回空响应")
# 处理SSE格式响应
if 'text/event-stream' in content_type or response_text.startswith('event:'):
logger.debug("检测到SSE格式响应,开始解析")
data = self._parse_sse_response(response_text)
else:
# 标准JSON响应
async def _ensure_connected(self):
"""确保连接已建立"""
async with self._lock:
if self._session is None:
try:
data = response.json()
except ValueError as e:
logger.error(f"JSON解析失败,响应内容: {response_text[:500]}")
raise MCPError(f"无法解析JSON响应: {str(e)}")
# 检查JSON-RPC错误
if "error" in data:
error = data["error"]
error_msg = error.get("message", "Unknown error")
error_code = error.get("code", -1)
logger.error(f"MCP错误 [{error_code}]: {error_msg}")
raise MCPError(f"[{error_code}] {error_msg}")
if "result" not in data:
raise MCPError("响应中缺少result字段")
return data["result"]
except httpx.HTTPStatusError as e:
logger.error(f"HTTP错误 {e.response.status_code}: {e.response.text}")
raise MCPError(f"HTTP错误 {e.response.status_code}: {e.response.text}")
except httpx.RequestError as e:
logger.error(f"请求错误: {str(e)}")
raise MCPError(f"请求错误: {str(e)}")
except MCPError:
raise
except Exception as e:
logger.error(f"未知错误: {str(e)}")
raise MCPError(f"未知错误: {str(e)}")
logger.info(f"🔗 连接到MCP服务器: {self.url}")
# 使用官方 SDK 的 streamable_http_client
# 保存上下文管理器以便后续正确清理
stream_context = streamablehttp_client(self.url)
read_stream, write_stream, _ = await stream_context.__aenter__()
self._context_stack.append(('stream', stream_context))
# 创建客户端会话
self._session = ClientSession(read_stream, write_stream)
session_context = self._session
await session_context.__aenter__()
self._context_stack.append(('session', session_context))
# 初始化会话
await self._session.initialize()
self._initialized = True
logger.info(f"✅ MCP会话初始化成功")
except Exception as e:
logger.error(f"❌ MCP连接失败: {e}")
await self._cleanup()
raise MCPError(f"连接MCP服务器失败: {str(e)}")
def _parse_sse_response(self, sse_text: str) -> Dict[str, Any]:
async def _cleanup(self):
"""清理连接资源(按照进入的相反顺序退出)"""
# 按照LIFO顺序清理上下文
while self._context_stack:
ctx_type, ctx = self._context_stack.pop()
try:
await ctx.__aexit__(None, None, None)
except RuntimeError as e:
# 忽略 anyio 的任务上下文错误(在关闭时可能发生)
if "cancel scope" in str(e).lower() or "different task" in str(e).lower():
logger.debug(f"忽略{ctx_type}上下文清理的任务切换警告: {e}")
else:
logger.error(f"清理{ctx_type}上下文失败: {e}")
except Exception as e:
logger.error(f"清理{ctx_type}上下文失败: {e}")
self._session = None
self._initialized = False
async def initialize(self) -> Dict[str, Any]:
"""
解析SSE格式的响应
初始化MCP会话
SSE格式示例:
event: message
data: {"result": {...}}
Args:
sse_text: SSE格式的文本
Returns:
解析后的JSON数据
初始化响应
"""
import json
lines = sse_text.strip().split('\n')
data_lines = []
for line in lines:
line = line.strip()
if line.startswith('data:'):
# 提取data后面的内容
data_content = line[5:].strip()
data_lines.append(data_content)
if not data_lines:
raise MCPError("SSE响应中没有找到data字段")
# 合并所有data行(某些SSE可能分多行)
full_data = ''.join(data_lines)
try:
return json.loads(full_data)
except json.JSONDecodeError as e:
logger.error(f"解析SSE data失败: {full_data[:200]}")
raise MCPError(f"SSE data不是有效的JSON: {str(e)}")
await self._ensure_connected()
return {"status": "initialized"}
async def list_tools(self) -> List[Dict[str, Any]]:
"""
@@ -196,13 +117,26 @@ class HTTPMCPClient:
工具列表
"""
try:
result = await self._call_jsonrpc("tools/list")
tools = result.get("tools", [])
await self._ensure_connected()
result = await self._session.list_tools()
# 转换为字典格式
tools = []
for tool in result.tools:
tool_dict = {
"name": tool.name,
"description": tool.description or "",
"inputSchema": tool.inputSchema
}
tools.append(tool_dict)
logger.info(f"获取到 {len(tools)} 个工具")
return tools
except Exception as e:
logger.error(f"获取工具列表失败: {e}")
raise
raise MCPError(f"获取工具列表失败: {str(e)}")
async def call_tool(
self,
@@ -220,33 +154,38 @@ class HTTPMCPClient:
工具执行结果
"""
try:
await self._ensure_connected()
logger.info(f"调用工具: {tool_name}")
logger.debug(f"参数: {arguments}")
result = await self._call_jsonrpc(
"tools/call",
{
"name": tool_name,
"arguments": arguments
}
)
result = await self._session.call_tool(tool_name, arguments)
# MCP返回的result通常包含content数组
if isinstance(result, dict) and "content" in result:
content = result["content"]
if isinstance(content, list) and len(content) > 0:
# 提取第一个content项的text
first_content = content[0]
if isinstance(first_content, dict) and "text" in first_content:
return first_content["text"]
return first_content
return content
# 处理返回结果
# MCP SDK 返回 CallToolResult 对象
if result.content:
# 提取第一个content的文本
for content in result.content:
if isinstance(content, types.TextContent):
return content.text
elif isinstance(content, types.ImageContent):
return {
"type": "image",
"data": content.data,
"mimeType": content.mimeType
}
# 如果没有文本内容,返回原始内容
return result.content[0] if result.content else None
return result
# 如果有结构化内容(2025-06-18规范)
if hasattr(result, 'structuredContent') and result.structuredContent:
return result.structuredContent
return None
except Exception as e:
logger.error(f"调用工具失败: {tool_name}, 错误: {e}")
raise
raise MCPError(f"调用工具失败: {str(e)}")
async def list_resources(self) -> List[Dict[str, Any]]:
"""
@@ -256,13 +195,27 @@ class HTTPMCPClient:
资源列表
"""
try:
result = await self._call_jsonrpc("resources/list")
resources = result.get("resources", [])
await self._ensure_connected()
result = await self._session.list_resources()
# 转换为字典格式
resources = []
for resource in result.resources:
resource_dict = {
"uri": str(resource.uri),
"name": resource.name,
"description": resource.description or "",
"mimeType": resource.mimeType or ""
}
resources.append(resource_dict)
logger.info(f"获取到 {len(resources)} 个资源")
return resources
except Exception as e:
logger.error(f"获取资源列表失败: {e}")
raise
raise MCPError(f"获取资源列表失败: {str(e)}")
async def read_resource(self, uri: str) -> Any:
"""
@@ -275,14 +228,33 @@ class HTTPMCPClient:
资源内容
"""
try:
result = await self._call_jsonrpc(
"resources/read",
{"uri": uri}
)
return result
await self._ensure_connected()
result = await self._session.read_resource(AnyUrl(uri))
# 提取资源内容
if result.contents:
content = result.contents[0]
if isinstance(content, types.TextContent):
return content.text
elif isinstance(content, types.ImageContent):
return {
"type": "image",
"data": content.data,
"mimeType": content.mimeType
}
elif isinstance(content, types.BlobResourceContents):
return {
"type": "blob",
"blob": content.blob,
"mimeType": content.mimeType
}
return None
except Exception as e:
logger.error(f"读取资源失败: {uri}, 错误: {e}")
raise
raise MCPError(f"读取资源失败: {str(e)}")
async def test_connection(self) -> Dict[str, Any]:
"""
@@ -291,10 +263,12 @@ class HTTPMCPClient:
Returns:
测试结果
"""
import time
start_time = time.time()
try:
# 尝试列举工具来测试连接
# 尝试连接并列举工具
await self._ensure_connected()
tools = await self.list_tools()
end_time = time.time()
@@ -307,22 +281,7 @@ class HTTPMCPClient:
"tools_count": len(tools),
"tools": tools
}
except MCPError as e:
end_time = time.time()
response_time = round((end_time - start_time) * 1000, 2)
return {
"success": False,
"message": "连接测试失败",
"response_time_ms": response_time,
"error": str(e),
"error_type": "MCPError",
"suggestions": [
"请检查服务器URL是否正确",
"请确认API Key是否有效",
"请检查网络连接"
]
}
except Exception as e:
end_time = time.time()
response_time = round((end_time - start_time) * 1000, 2)
@@ -334,12 +293,41 @@ class HTTPMCPClient:
"error": str(e),
"error_type": type(e).__name__,
"suggestions": [
"请检查服务器是否在线",
"请确认配置是否正确"
"请检查服务器URL是否正确",
"请确认API Key是否有效",
"请检查网络连接",
"请确认MCP服务器是否在线"
]
}
async def close(self):
"""关闭客户端(仅在拥有客户端所有权时关闭)"""
if self._owns_client and self.client:
await self.client.aclose()
"""关闭客户端连接"""
logger.info(f"关闭MCP客户端: {self.url}")
await self._cleanup()
@asynccontextmanager
async def create_mcp_client(
url: str,
headers: Optional[Dict[str, str]] = None,
env: Optional[Dict[str, str]] = None,
timeout: float = 60.0
):
"""
创建MCP客户端的上下文管理器
Args:
url: MCP服务器URL
headers: HTTP请求头
env: 环境变量
timeout: 超时时间
Yields:
HTTPMCPClient实例
"""
client = HTTPMCPClient(url, headers, env, timeout)
try:
await client.initialize()
yield client
finally:
await client.close()