import express, { Request, Response } from "express";
import morgan from "morgan";
import { SSEServerTransport } from "@modelcontextprotocol/sdk/server/sse.js";
import { useRequestId } from "./utils/useID.js";
import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
// SSE Transports
const transports: { [sessionId: string]: SSEServerTransport } = {};
// SSE Server Init
const app = express();
// Middlewares
app.use(morgan("combined"));
app.use(useRequestId);
// SSE Routes
export function SSEServer(server: McpServer) {
// SSE Connection
app.get("/sse", async (_: Request, res: Response) => {
const transport = new SSEServerTransport("/messages", res);
transports[transport.sessionId] = transport;
res.on("close", () => {
delete transports[transport.sessionId];
});
await server.connect(transport);
});
// SSE Post Message
app.post("/messages", async (req: Request, res: Response) => {
const sessionId = req.query.sessionId as string;
const transport = transports[sessionId];
if (transport) {
await transport.handlePostMessage(req, res);
} else {
res.status(400).send("No transport found for sessionId");
}
});
// SSE Startup
app.listen(process.env.PORT, () => {
console.log(`[MCP] Server started on port ${process.env.PORT}`);
});
}
