279 lines
10 KiB
Python
279 lines
10 KiB
Python
"""
|
|
Main MCP Browser proxy implementation.
|
|
|
|
Provides a generic, minimalistic interface for interacting with MCP servers
|
|
with automatic routing, sparse mode, and context optimization.
|
|
"""
|
|
|
|
import json
|
|
import asyncio
|
|
from typing import Dict, Any, Optional, Union
|
|
from pathlib import Path
|
|
|
|
from .config import ConfigLoader, MCPBrowserConfig
|
|
from .server import MCPServer
|
|
from .multi_server import MultiServerManager
|
|
from .registry import ToolRegistry
|
|
from .filter import MessageFilter, VirtualToolHandler
|
|
from .buffer import JsonRpcBuffer
|
|
|
|
|
|
class MCPBrowser:
|
|
"""
|
|
Generic MCP protocol browser with minimal API.
|
|
|
|
Provides two main methods:
|
|
- call(): Execute any JSON-RPC call
|
|
- discover(): Explore available tools using JSONPath
|
|
"""
|
|
|
|
def __init__(self, config_path: Optional[Path] = None, server_name: Optional[str] = None,
|
|
enable_builtin_servers: bool = True):
|
|
"""
|
|
Initialize MCP Browser.
|
|
|
|
Args:
|
|
config_path: Optional path to configuration file
|
|
server_name: Optional MCP server name to use (overrides default)
|
|
enable_builtin_servers: Whether to start built-in servers (screen, memory, etc.)
|
|
"""
|
|
self.config_loader = ConfigLoader(config_path)
|
|
self.config: Optional[MCPBrowserConfig] = None
|
|
self.server: Optional[MCPServer] = None
|
|
self.multi_server: Optional[MultiServerManager] = None
|
|
self.registry = ToolRegistry()
|
|
self.filter: Optional[MessageFilter] = None
|
|
self.virtual_handler: Optional[VirtualToolHandler] = None
|
|
self._server_name = server_name
|
|
self._enable_builtin_servers = enable_builtin_servers
|
|
self._initialized = False
|
|
self._response_buffer: Dict[Union[str, int], asyncio.Future] = {}
|
|
self._next_id = 1
|
|
|
|
async def __aenter__(self):
|
|
"""Async context manager entry."""
|
|
await self.initialize()
|
|
return self
|
|
|
|
async def __aexit__(self, exc_type, exc_val, exc_tb):
|
|
"""Async context manager exit."""
|
|
await self.close()
|
|
|
|
async def initialize(self):
|
|
"""Initialize the browser and start MCP server."""
|
|
if self._initialized:
|
|
return
|
|
|
|
# Load configuration
|
|
self.config = self.config_loader.load()
|
|
|
|
# Determine which server to use
|
|
server_name = self._server_name or self.config.default_server
|
|
if not server_name or server_name not in self.config.servers:
|
|
raise ValueError(f"Server '{server_name}' not found in configuration")
|
|
|
|
server_config = self.config.servers[server_name]
|
|
|
|
# Create multi-server manager if using built-in servers
|
|
if self._enable_builtin_servers:
|
|
self.multi_server = MultiServerManager(debug=self.config.debug)
|
|
await self.multi_server.start_builtin_servers()
|
|
|
|
# Create main server if specified
|
|
if server_name != "builtin-only":
|
|
self.server = MCPServer(server_config, debug=self.config.debug)
|
|
# Set up message handling
|
|
self.server.add_message_handler(self._handle_server_message)
|
|
# Start server
|
|
await self.server.start()
|
|
|
|
# Create filter and handler
|
|
self.filter = MessageFilter(self.registry, sparse_mode=self.config.sparse_mode)
|
|
self.virtual_handler = VirtualToolHandler(self.registry, self._forward_to_server)
|
|
|
|
# Initialize connection
|
|
await self._initialize_connection()
|
|
|
|
self._initialized = True
|
|
|
|
async def close(self):
|
|
"""Close the browser and stop all MCP servers."""
|
|
if self.server:
|
|
await self.server.stop()
|
|
if self.multi_server:
|
|
await self.multi_server.stop_all()
|
|
self._initialized = False
|
|
|
|
async def call(self, jsonrpc_object: Dict[str, Any]) -> Dict[str, Any]:
|
|
"""
|
|
Execute a JSON-RPC call.
|
|
|
|
This is the main generic interface for all MCP operations.
|
|
|
|
Args:
|
|
jsonrpc_object: Complete JSON-RPC request object
|
|
|
|
Returns:
|
|
JSON-RPC response object
|
|
|
|
Example:
|
|
response = await browser.call({
|
|
"jsonrpc": "2.0",
|
|
"id": 1,
|
|
"method": "tools/call",
|
|
"params": {
|
|
"name": "Bash",
|
|
"arguments": {"command": "ls"}
|
|
}
|
|
})
|
|
"""
|
|
if not self._initialized:
|
|
await self.initialize()
|
|
|
|
# Ensure request has an ID
|
|
if "id" not in jsonrpc_object:
|
|
jsonrpc_object = jsonrpc_object.copy()
|
|
jsonrpc_object["id"] = self._next_id
|
|
self._next_id += 1
|
|
|
|
request_id = jsonrpc_object["id"]
|
|
|
|
# Check if this is a virtual tool call
|
|
if jsonrpc_object.get("method") == "tools/call":
|
|
tool_name = jsonrpc_object.get("params", {}).get("name")
|
|
|
|
if self.filter.is_virtual_tool(tool_name):
|
|
# Handle virtual tool locally
|
|
response = await self.virtual_handler.handle_tool_call(jsonrpc_object)
|
|
if response:
|
|
return response
|
|
elif tool_name == "onboarding" and self.multi_server:
|
|
# Special handling for onboarding tool - route to built-in server
|
|
try:
|
|
args = jsonrpc_object.get("params", {}).get("arguments", {})
|
|
response = await self.multi_server.route_tool_call(
|
|
"builtin:onboarding::onboarding", args
|
|
)
|
|
return {
|
|
"jsonrpc": "2.0",
|
|
"id": request_id,
|
|
"result": response
|
|
}
|
|
except Exception as e:
|
|
return {
|
|
"jsonrpc": "2.0",
|
|
"id": request_id,
|
|
"error": {"code": -32603, "message": str(e)}
|
|
}
|
|
|
|
# Create future for response
|
|
future = asyncio.Future()
|
|
self._response_buffer[request_id] = future
|
|
|
|
# Send to server
|
|
self.server.send_raw(json.dumps(jsonrpc_object))
|
|
|
|
# Wait for response
|
|
try:
|
|
response = await asyncio.wait_for(future, timeout=self.config.timeout)
|
|
return response
|
|
except asyncio.TimeoutError:
|
|
del self._response_buffer[request_id]
|
|
return {
|
|
"jsonrpc": "2.0",
|
|
"id": request_id,
|
|
"error": {
|
|
"code": -32603,
|
|
"message": "Request timeout"
|
|
}
|
|
}
|
|
|
|
def discover(self, jsonpath: str) -> Any:
|
|
"""
|
|
Discover available tools and their properties using JSONPath.
|
|
|
|
This is a synchronous convenience method for tool discovery.
|
|
|
|
Args:
|
|
jsonpath: JSONPath expression to query tool registry
|
|
|
|
Returns:
|
|
Query results (list, dict, or primitive value)
|
|
|
|
Examples:
|
|
# Get all tool names
|
|
tools = browser.discover("$.tools[*].name")
|
|
|
|
# Get specific tool
|
|
bash_tool = browser.discover("$.tools[?(@.name=='Bash')]")
|
|
|
|
# Get all input schemas
|
|
schemas = browser.discover("$.tools[*].inputSchema")
|
|
"""
|
|
return self.registry.discover(jsonpath)
|
|
|
|
async def _initialize_connection(self):
|
|
"""Initialize MCP connection and populate tool registry."""
|
|
# Send initialize request
|
|
init_response = await self.call({
|
|
"jsonrpc": "2.0",
|
|
"id": "init",
|
|
"method": "initialize",
|
|
"params": {
|
|
"protocolVersion": "0.1.0",
|
|
"capabilities": {},
|
|
"clientInfo": {
|
|
"name": "mcp-browser",
|
|
"version": "0.1.0"
|
|
}
|
|
}
|
|
})
|
|
|
|
if "error" in init_response:
|
|
raise RuntimeError(f"Failed to initialize: {init_response['error']}")
|
|
|
|
# Get tool list from main server
|
|
if self.server:
|
|
tools_response = await self.call({
|
|
"jsonrpc": "2.0",
|
|
"id": "tools",
|
|
"method": "tools/list",
|
|
"params": {}
|
|
})
|
|
|
|
if "error" in tools_response:
|
|
raise RuntimeError(f"Failed to list tools: {tools_response['error']}")
|
|
|
|
# Also get tools from multi-server if enabled
|
|
if self.multi_server:
|
|
builtin_tools = await self.multi_server.get_all_tools()
|
|
# Add to registry without going through filter
|
|
existing_tools = self.registry.raw_tool_list
|
|
self.registry.update_tools(existing_tools + builtin_tools)
|
|
|
|
def _handle_server_message(self, message: dict):
|
|
"""Handle incoming message from MCP server."""
|
|
# Apply incoming filter
|
|
filtered = self.filter.filter_incoming(message)
|
|
if not filtered:
|
|
return
|
|
|
|
# Check if this is a response to a pending request
|
|
msg_id = filtered.get("id")
|
|
if msg_id in self._response_buffer:
|
|
future = self._response_buffer.pop(msg_id)
|
|
future.set_result(filtered)
|
|
|
|
async def _forward_to_server(self, request: dict) -> dict:
|
|
"""Forward a request to the MCP server and get response."""
|
|
# This is used by the virtual tool handler for mcp_call
|
|
return await self.call(request)
|
|
|
|
|
|
# Convenience function for simple usage
|
|
async def create_browser(config_path: Optional[Path] = None,
|
|
server_name: Optional[str] = None) -> MCPBrowser:
|
|
"""Create and initialize an MCP Browser instance."""
|
|
browser = MCPBrowser(config_path, server_name)
|
|
await browser.initialize()
|
|
return browser |