URL2QR MCP Server

import express, { Request, Response } from "express"; import cors from "cors"; import { randomUUID } from "node:crypto"; import path from "node:path"; import "dotenv/config"; import { Server } from "@modelcontextprotocol/sdk/server/index.js"; import { CallToolRequestSchema, ListToolsRequestSchema, CallToolResult, Tool } from "@modelcontextprotocol/sdk/types.js"; // Import business tools import { url2qr } from "./tools/url2qr.js"; // Session storage (maintaining sessions via headers in stateless HTTP) interface Session { id: string; server: Server; createdAt: Date; lastActivity: Date } const sessions = new Map<string, Session>(); function createMCPServer(): Server { const server = new Server( { name: "URL2QR-MCP", version: "1.0.0" }, { capabilities: { tools: {} } } ); const tools: Tool[] = [ { name: url2qr.name, description: url2qr.description, inputSchema: url2qr.parameters as any } ]; server.setRequestHandler(ListToolsRequestSchema, async () => ({ tools })); server.setRequestHandler(CallToolRequestSchema, async (request): Promise<CallToolResult> => { const { name, arguments: args } = request.params as any; switch (name) { case "url_to_qrcode": return await url2qr.run(args); default: throw new Error(`Unknown tool: ${name}`); } }); return server; } const app = express(); const PORT = Number(process.env.PORT) || 3000; const QR_OUTPUT_DIR = process.env.QR_OUTPUT_DIR || "./qrcodes"; const PUBLIC_BASE_URL = (process.env.PUBLIC_BASE_URL || `http://localhost:${PORT}`).replace(/\/$/, ""); app.use(cors({ origin: "*", methods: ["GET", "POST", "OPTIONS"], allowedHeaders: ["Content-Type", "Accept", "Authorization", "Mcp-Session-Id", "Last-Event-ID"], exposedHeaders: ["Content-Type", "Mcp-Session-Id"] })); app.use(express.json({ limit: "10mb" })); // Static file serving for QR codes app.use("/qrcodes", express.static(path.resolve(QR_OUTPUT_DIR))); // Health check app.get("/health", (_req: Request, res: Response) => { res.json({ status: "healthy", transport: "streamable-http", activeSessions: sessions.size, serverName: "URL2QR-MCP", version: "1.0.0" }); }); // Root endpoint with API info app.get("/", (_req: Request, res: Response) => { res.json({ name: "URL2QR MCP Server", version: "1.0.0", description: "MCP server that converts URLs to QR codes", endpoints: { mcp: "/mcp", health: "/health", qrcodes: "/qrcodes/:filename" }, author: { name: "Xingyu Chen", github: "https://github.com/guangxiangdebizi", npm: "https://www.npmjs.com/~xingyuchen" } }); }); // Streamable HTTP main endpoint: POST /mcp (JSON-RPC) app.all("/mcp", async (req: Request, res: Response) => { const sessionIdHeader = req.headers["mcp-session-id"] as string | undefined; const method = req.method.toUpperCase(); if (method === "POST") { const body = req.body; if (!body) return res.status(400).json({ jsonrpc: "2.0", error: { code: -32600, message: "Empty body" }, id: null }); // Ignore notifications (like notifications/initialized) const isNotification = (body.id === undefined || body.id === null) && typeof body.method === "string" && body.method.startsWith("notifications/"); if (isNotification) { if (sessionIdHeader && sessions.has(sessionIdHeader)) sessions.get(sessionIdHeader)!.lastActivity = new Date(); return res.status(204).end(); } // Initialize/session management const isInit = body.method === "initialize"; let session: Session | undefined; if (sessionIdHeader && sessions.has(sessionIdHeader)) { session = sessions.get(sessionIdHeader)!; session.lastActivity = new Date(); } else if (isInit) { const newId = randomUUID(); const server = createMCPServer(); session = { id: newId, server, createdAt: new Date(), lastActivity: new Date() }; sessions.set(newId, session); res.setHeader("Mcp-Session-Id", newId); } else { return res.status(400).json({ jsonrpc: "2.0", error: { code: -32000, message: "No session and not initialize" }, id: null }); } // Handle core methods if (body.method === "initialize") { return res.json({ jsonrpc: "2.0", result: { protocolVersion: "2024-11-05", capabilities: { tools: {} }, serverInfo: { name: "URL2QR-MCP", version: "1.0.0" } }, id: body.id }); } if (body.method === "tools/list") { const tools = [ { name: url2qr.name, description: url2qr.description, inputSchema: url2qr.parameters } ]; return res.json({ jsonrpc: "2.0", result: { tools }, id: body.id }); } if (body.method === "tools/call") { const { name, arguments: args } = body.params; // Auto-detect host from request headers (supports proxies and different deployments) const protocol = req.headers['x-forwarded-proto'] || (req.secure ? 'https' : 'http'); const host = req.headers['x-forwarded-host'] || req.headers['host'] || `localhost:${PORT}`; const hostBaseUrl = `${protocol}://${host}`; let result: any; switch (name) { case "url_to_qrcode": result = await url2qr.run(args, { hostBaseUrl }); break; default: throw new Error(`Unknown tool: ${name}`); } return res.json({ jsonrpc: "2.0", result, id: body.id }); } return res.status(400).json({ jsonrpc: "2.0", error: { code: -32601, message: `Method not found: ${body.method}` }, id: body.id }); } return res.status(405).json({ jsonrpc: "2.0", error: { code: -32600, message: "Method Not Allowed" }, id: null }); }); // Session cleanup (every 30 minutes) setInterval(() => { const now = new Date(); const timeout = 30 * 60 * 1000; // 30 minutes for (const [id, session] of sessions.entries()) { if (now.getTime() - session.lastActivity.getTime() > timeout) { sessions.delete(id); console.log(`Session ${id} expired and removed`); } } }, 15 * 60 * 1000); // Run every 15 minutes // Start server (Streamable HTTP mode) app.listen(PORT, () => { console.log(`\n🚀 URL2QR MCP Server Started`); console.log(` Transport: Streamable HTTP`); console.log(` MCP endpoint: http://localhost:${PORT}/mcp`); console.log(` Health check: http://localhost:${PORT}/health`); console.log(` QR codes: http://localhost:${PORT}/qrcodes/`); console.log(`\n📝 Author: Xingyu Chen`); console.log(` GitHub: https://github.com/guangxiangdebizi`); console.log(` npm: https://www.npmjs.com/~xingyuchen\n`); });