macuse

import { Server } from "@modelcontextprotocol/sdk/server/index.js"; import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js"; import { CallToolRequestSchema, ListToolsRequestSchema, } from "@modelcontextprotocol/sdk/types.js"; import { MacuseClient } from "../client/macuse-client.js"; /** * Stdio MCP Server that proxies requests to Macuse MCP server */ export class MacuseProxyServer { private server: Server; private macuseClient: MacuseClient | null = null; private connectPromise: Promise<void> | null = null; constructor() { this.server = new Server( { name: "macuse-mcp-proxy", version: __VERSION__, }, { capabilities: { tools: {}, }, }, ); this.setupHandlers(); } private setupHandlers() { // Tools this.server.setRequestHandler(ListToolsRequestSchema, async () => { await this.ensureConnected(); if (!this.macuseClient) throw new Error("Client not connected"); return await this.macuseClient.listTools(); }); this.server.setRequestHandler(CallToolRequestSchema, async (request) => { const { name, arguments: args } = request.params; try { await this.ensureConnected(); if (!this.macuseClient) throw new Error("Client not connected"); return await this.macuseClient.callTool(name, args || {}); } catch (error) { return { content: [ { type: "text", text: JSON.stringify( { error: error instanceof Error ? error.message : "Unknown error", tool: name, timestamp: new Date().toISOString(), }, null, 2, ), }, ], isError: true, }; } }); this.server.onerror = (error) => { console.error(`MCP Proxy Server error: ${error}\n`); }; } /** * Ensure connection to Macuse MCP server */ private async ensureConnected(): Promise<void> { // If the client is already connected, return immediately if (this.macuseClient) { return; } // If a connection is already in progress, wait for it to complete if (this.connectPromise) { return await this.connectPromise; } // Start a new connection and "lock" it this.connectPromise = (async () => { try { const macuseClient = new MacuseClient(); await macuseClient.connect(); this.macuseClient = macuseClient; } catch (error) { // If the connection fails, clear the "lock" to allow retry this.connectPromise = null; console.error(`Failed to connect to Macuse: ${error}\n`); throw error; } })(); return await this.connectPromise; } /** * Start the stdio server */ async start(): Promise<void> { try { const transport = new StdioServerTransport(); await this.server.connect(transport); } catch (error) { console.error(`Failed to start proxy server: ${error}\n`); process.exit(1); } } /** * Stop the server */ async stop(): Promise<void> { try { if (this.macuseClient) { await this.macuseClient.close(); } } catch (error) { console.error(`Error during server shutdown: ${error}\n`); } } }