http.ts•5.05 kB
/**
* HTTP transport (streamable) for production/cloud deployment
*/
import { createServer, IncomingMessage, ServerResponse } from 'http';
import { randomUUID } from 'crypto';
import { StreamableHTTPServerTransport } from '@modelcontextprotocol/sdk/server/streamableHttp.js';
import { Config } from '../config.js';
import { NexarServer } from '../server.js';
interface Session {
transport: StreamableHTTPServerTransport;
server: NexarServer;
}
const sessions = new Map<string, Session>();
function createStandaloneServer(clientId: string, clientSecret: string): NexarServer {
return new NexarServer(clientId, clientSecret);
}
export function startHttpTransport(config: Config): void {
const httpServer = createServer(async (req, res) => {
// CORS headers
res.setHeader('Access-Control-Allow-Origin', '*');
res.setHeader('Access-Control-Allow-Methods', 'GET, POST, OPTIONS');
res.setHeader('Access-Control-Allow-Headers', 'Content-Type, mcp-session-id');
if (req.method === 'OPTIONS') {
res.writeHead(200);
res.end();
return;
}
const url = new URL(req.url || '/', `http://${req.headers.host}`);
switch (url.pathname) {
case '/health':
handleHealthCheck(res);
break;
case '/mcp':
await handleMcpRequest(req, res, config);
break;
case '/sse':
await handleSSERequest(req, res, config);
break;
default:
handleNotFound(res);
}
});
const host = config.isProduction ? '0.0.0.0' : 'localhost';
httpServer.listen(config.port, host, () => {
logServerStart(config);
});
}
async function handleMcpRequest(
req: IncomingMessage,
res: ServerResponse,
config: Config
): Promise<void> {
const sessionId = req.headers['mcp-session-id'] as string | undefined;
if (sessionId) {
const session = sessions.get(sessionId);
if (!session) {
res.statusCode = 404;
res.end('Session not found');
return;
}
return await session.transport.handleRequest(req, res);
}
if (req.method === 'POST') {
await createNewSession(req, res, config);
return;
}
res.statusCode = 400;
res.end('Invalid request');
}
async function handleSSERequest(
req: IncomingMessage,
res: ServerResponse,
config: Config
): Promise<void> {
// SSE endpoint for backward compatibility
// Use streamable HTTP transport instead
const serverInstance = createStandaloneServer(config.clientId, config.clientSecret);
const transport = new StreamableHTTPServerTransport({
sessionIdGenerator: () => randomUUID(),
});
try {
await serverInstance.getServer().connect(transport);
console.log('SSE connection established (using streamable HTTP)');
// Note: SSE endpoint uses streamable HTTP transport for compatibility
await transport.handleRequest(req, res);
} catch (error) {
console.error('SSE connection error:', error);
res.statusCode = 500;
res.end('SSE connection failed');
}
}
async function createNewSession(
req: IncomingMessage,
res: ServerResponse,
config: Config
): Promise<void> {
const serverInstance = createStandaloneServer(config.clientId, config.clientSecret);
const transport = new StreamableHTTPServerTransport({
sessionIdGenerator: () => randomUUID(),
onsessioninitialized: (sessionId) => {
sessions.set(sessionId, { transport, server: serverInstance });
console.log('New Nexar session created:', sessionId);
},
});
transport.onclose = () => {
if (transport.sessionId) {
sessions.delete(transport.sessionId);
console.log('Nexar session closed:', transport.sessionId);
}
};
try {
await serverInstance.getServer().connect(transport);
console.log('MCP server connected to transport, ready to handle requests');
await transport.handleRequest(req, res);
} catch (error) {
console.error('Streamable HTTP connection error:', error);
res.statusCode = 500;
res.end('Internal server error');
}
}
function handleHealthCheck(res: ServerResponse): void {
res.writeHead(200, { 'Content-Type': 'application/json' });
res.end(
JSON.stringify({
status: 'healthy',
timestamp: new Date().toISOString(),
service: 'nexar-mcp',
version: '0.1.0',
})
);
}
function handleNotFound(res: ServerResponse): void {
res.writeHead(404, { 'Content-Type': 'text/plain' });
res.end('Not Found');
}
function logServerStart(config: Config): void {
const displayUrl = config.isProduction ? `Port ${config.port}` : `http://localhost:${config.port}`;
console.log(`Nexar MCP Server listening on ${displayUrl}`);
if (!config.isProduction) {
console.log('Put this in your client config:');
console.log(
JSON.stringify(
{
mcpServers: {
nexar: {
url: `http://localhost:${config.port}/mcp`,
},
},
},
null,
2
)
);
console.log('For backward compatibility, you can also use the /sse endpoint.');
}
}