ReMe/reme/components/client/mcp_client.py
jinliyl ad7893e9c4
fix(mcp): resolve circular import issues and update dependencies (#296)
* fix(mcp): resolve circular import issues and update dependencies

- Moved fastmcp imports inside functions to prevent circular dependencies
- Replaced _TRANSPORT_MAP with _VALID_TRANSPORTS set for transport validation
- Updated version number from 0.4.0.3 to 0.4.0.4
- Added claude-agent-sdk dependency to core optional dependencies
- Used TYPE_CHECKING imports for FastMCP related types
- Restructured transport mapping logic within function scope
- Fixed string annotation for CallToolResult type hints

* refactor(tests): update date handling in daily steps tests

- Replace _date.today() with timezone-aware now function
- Use Asia/Shanghai timezone for date formatting
- Change return format to use strftime instead of isoformat
- Import now function from reme.steps.evolve module

* refactor(tests): clean up unused imports in daily steps test

- Removed unused date import from datetime module
- Removed redundant pathlib Path import that was already imported later
- Kept necessary imports for asyncio, os, tempfile, warnings, and frontmatter modules

* test(daily_steps): update test to include application context for daily list step

- Add ApplicationContext initialization with temporary workspace directory
- Register file store component in application context
- Pass application context to DailyListStep constructor
- Maintain existing test assertion behavior for date metadata verification
2026-06-26 09:37:08 +08:00

127 lines
4.4 KiB
Python

"""MCP client for ReMe services."""
import json
import os
from collections.abc import AsyncGenerator
from typing import TYPE_CHECKING, Any
from .base_client import BaseClient
from ..component_registry import R
from ...constants import REME_SERVICE_INFO, REME_DEFAULT_HOST, REME_DEFAULT_PORT
if TYPE_CHECKING:
from fastmcp.client.client import CallToolResult
_VALID_TRANSPORTS = {"sse", "stdio", "streamable-http"}
@R.register("mcp")
class MCPClient(BaseClient):
"""MCP client that communicates with ReMe MCP service via fastmcp.Client.
Usage:
# SSE (default)
client = MCPClient(host="localhost", port=8000)
async with client:
async for text in client(action="my_tool", query="hello"):
print(text)
# Streamable HTTP
client = MCPClient(transport="streamable-http", host="localhost", port=8000)
# Stdio
client = MCPClient(transport="stdio", command="python", args=["server.py"])
# Custom transport object
from fastmcp.client import SSETransport
client = MCPClient(transport=SSETransport(url="http://host:port/sse"))
"""
def __init__(
self,
transport: str | Any = "sse",
host: str | None = None,
port: int | None = None,
timeout: float = 30.0,
**kwargs,
):
super().__init__(**kwargs)
if isinstance(transport, str) and transport not in _VALID_TRANSPORTS:
raise ValueError(f"Unknown transport: {transport!r}, expected one of {sorted(_VALID_TRANSPORTS)}")
if isinstance(transport, str) and transport != "stdio":
if not (host and port):
if service_info := os.environ.get(REME_SERVICE_INFO):
try:
data = json.loads(service_info)
host = data["host"]
port = data["port"]
except Exception:
self.logger.warning(f"Invalid service info: {service_info}")
host, port = REME_DEFAULT_HOST, REME_DEFAULT_PORT
else:
host, port = REME_DEFAULT_HOST, REME_DEFAULT_PORT
self.host = host
self.port = port
self.transport = transport
self.timeout = timeout
def _build_transport(self):
if not isinstance(self.transport, str):
return self.transport
from fastmcp.client import SSETransport, StdioTransport, StreamableHttpTransport
transport_map = {
"sse": SSETransport,
"stdio": StdioTransport,
"streamable-http": StreamableHttpTransport,
}
cls = transport_map[self.transport]
if self.transport == "stdio":
command = self.kwargs.get("command", "")
args = self.kwargs.get("args", [])
return cls(command=command, args=args)
path = "/sse" if self.transport == "sse" else "/mcp"
url = f"http://{self.host}:{self.port}{path}"
return cls(url=url)
# pylint: disable=unnecessary-dunder-call
async def _start(self) -> None:
if self.client is None:
from fastmcp import Client
self.client = Client(self._build_transport(), timeout=self.timeout)
await self.client.__aenter__()
# pylint: disable=invalid-overridden-method
async def _execute(self, action: str, payload: dict) -> AsyncGenerator[str, None]:
if self.client is None:
raise RuntimeError("Client not initialized. Call _start() first.")
result: "CallToolResult" = await self.client.call_tool(action, payload)
yield self._extract_text(result)
async def list_actions(self) -> list[dict]:
"""Return raw MCP Tool dumps; each dict gets an `action` key (the tool name)."""
if self.client is None:
raise RuntimeError("Client not initialized. Call _start() first.")
tools = await self.client.list_tools()
return [tool.model_dump() for tool in tools]
# pylint: disable=unnecessary-dunder-call
async def _close(self) -> None:
if self.client is not None:
await self.client.__aexit__(None, None, None)
self.client = None
@staticmethod
def _extract_text(result: "CallToolResult") -> str:
for block in result.content:
if hasattr(block, "text"):
return block.text
return str(result.content)