import { SSEServerTransport } from "@modelcontextprotocol/sdk/server/sse.js";
import express from "express";
import type { Request, Response } from "express";
import { getServer } from "./server.js";
import { config } from "./config.js";
import { authorizationHeaderName } from "./const.js";
export async function startSSE() {
const server = await getServer(config);
const app = express();
// to support multiple simultaneous connections we have a lookup object from
// sessionId to transport
const transports: { [sessionId: string]: SSEServerTransport } = {};
app.get("/sse", async (req: Request, res: Response) => {
const authHeaderValue = (req.headers[authorizationHeaderName] as string ?? "")
.replace(/Bearer\s+/i, '');
if (config.authorizationHeader === ""
|| config.authorizationHeader === authHeaderValue) {
const transport = new SSEServerTransport('/messages', res);
transports[transport.sessionId] = transport;
res.on("close", () => {
delete transports[transport.sessionId];
});
await server.connect(transport);
} else {
res.status(401).send('Unauthorized');
}
});
app.post("/messages", async (req: Request, res: Response) => {
const authHeaderValue = (req.headers[authorizationHeaderName] as string ?? "")
.replace(/Bearer\s+/i, '');
if (config.authorizationHeader === ""
|| config.authorizationHeader === authHeaderValue) {
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');
}
} else {
res.status(401).send('Unauthorized');
}
});
app.listen(3001);
}
