Feishu/Lark OpenAPI MCP

import express, { NextFunction, Request, Response } from 'express'; import { StreamableHTTPServerTransport } from '@modelcontextprotocol/sdk/server/streamableHttp.js'; import { InitTransportServerFunction } from '../shared'; import { parseMCPServerOptionsFromRequest, sendJsonRpcError } from './utils'; import { LarkAuthHandler } from '../../auth'; import { logger } from '../../utils/logger'; export const initStreamableServer: InitTransportServerFunction = ( getNewServer, options, { needAuthFlow } = { needAuthFlow: false }, ) => { const { userAccessToken, oauth, port, host } = options; if (!port || !host) { throw new Error('[Lark MCP] Port and host are required'); } const app = express(); app.use(express.json()); let authHandler: LarkAuthHandler | undefined; if (!userAccessToken && needAuthFlow) { authHandler = new LarkAuthHandler(app, options); if (oauth) { authHandler.setupRoutes(); } } const authMiddleware = (req: Request, res: Response, next: NextFunction) => { if (authHandler && oauth) { authHandler.authenticateRequest(req, res, next); } else { const authToken = req.headers.authorization?.split(' ')[1]; if (authToken) { req.auth = { token: authToken, clientId: 'client_id_for_local_auth', scopes: [] }; } next(); } }; app.post('/mcp', authMiddleware, async (req: Request, res: Response) => { const token = req.auth?.token; const { data } = parseMCPServerOptionsFromRequest(req); const server = getNewServer({ ...options, ...data, userAccessToken: data.userAccessToken || token }, authHandler); const transport = new StreamableHTTPServerTransport({ sessionIdGenerator: undefined }); res.on('close', () => { transport.close(); server.close(); }); await server.connect(transport); await transport.handleRequest(req, res, req.body); }); const handleMethodNotAllowed = async (_req: Request, res: Response) => { res .writeHead(405) .end(JSON.stringify({ jsonrpc: '2.0', error: { code: -32000, message: 'Method not allowed.' }, id: null })); }; app.get('/mcp', async (req: Request, res: Response) => { try { console.log('Received GET MCP request'); logger.info(`[StreamableServerTransport] Received GET MCP request`); await handleMethodNotAllowed(req, res); } catch (error) { sendJsonRpcError(res, error as Error); } }); app.delete('/mcp', async (req: Request, res: Response) => { try { console.log('Received DELETE MCP request'); logger.info(`[StreamableServerTransport] Received DELETE MCP request`); await handleMethodNotAllowed(req, res); } catch (error) { sendJsonRpcError(res, error as Error); } }); app.listen(port, host, (error) => { if (error) { logger.error(`[StreamableServerTransport] Server error: ${error}`); process.exit(1); } console.log(`📡 Streamable endpoint: http://${host}:${port}/mcp`); logger.info(`[StreamableServerTransport] Streamable endpoint: http://${host}:${port}/mcp`); }); };