142 lines
3.9 KiB
JavaScript
142 lines
3.9 KiB
JavaScript
#!/usr/bin/env node
|
|
|
|
import cors from "cors";
|
|
import EventSource from "eventsource";
|
|
import { parseArgs } from "node:util";
|
|
|
|
import { SSEClientTransport } from "@modelcontextprotocol/sdk/client/sse.js";
|
|
import {
|
|
StdioClientTransport,
|
|
getDefaultEnvironment,
|
|
} from "@modelcontextprotocol/sdk/client/stdio.js";
|
|
import { SSEServerTransport } from "@modelcontextprotocol/sdk/server/sse.js";
|
|
import express from "express";
|
|
import mcpProxy from "./mcpProxy.js";
|
|
|
|
// Polyfill EventSource for an SSE client in Node.js
|
|
// eslint-disable-next-line @typescript-eslint/no-explicit-any
|
|
(global as any).EventSource = EventSource;
|
|
|
|
const { values } = parseArgs({
|
|
args: process.argv.slice(2),
|
|
options: {
|
|
env: { type: "string", default: "" },
|
|
args: { type: "string", default: "" },
|
|
},
|
|
});
|
|
|
|
const app = express();
|
|
app.use(cors());
|
|
|
|
let webAppTransports: SSEServerTransport[] = [];
|
|
|
|
const createTransport = async (query: express.Request["query"]) => {
|
|
console.log("Query parameters:", query);
|
|
|
|
const transportType = query.transportType as string;
|
|
|
|
if (transportType === "stdio") {
|
|
const command = query.command as string;
|
|
const args = (query.args as string).split(/\s+/);
|
|
const env = query.env ? JSON.parse(query.env as string) : undefined;
|
|
console.log(
|
|
`Stdio transport: command=${command}, args=${args}, env=${JSON.stringify(env)}`,
|
|
);
|
|
const transport = new StdioClientTransport({
|
|
command,
|
|
args,
|
|
env,
|
|
stderr: "pipe",
|
|
});
|
|
await transport.start();
|
|
console.log("Spawned stdio transport");
|
|
return transport;
|
|
} else if (transportType === "sse") {
|
|
const url = query.url as string;
|
|
console.log(`SSE transport: url=${url}`);
|
|
const transport = new SSEClientTransport(new URL(url));
|
|
await transport.start();
|
|
console.log("Connected to SSE transport");
|
|
return transport;
|
|
} else {
|
|
console.error(`Invalid transport type: ${transportType}`);
|
|
throw new Error("Invalid transport type specified");
|
|
}
|
|
};
|
|
|
|
app.get("/sse", async (req, res) => {
|
|
try {
|
|
console.log("New SSE connection");
|
|
|
|
const backingServerTransport = await createTransport(req.query);
|
|
|
|
console.log("Connected MCP client to backing server transport");
|
|
|
|
const webAppTransport = new SSEServerTransport("/message", res);
|
|
console.log("Created web app transport");
|
|
|
|
webAppTransports.push(webAppTransport);
|
|
console.log("Created web app transport");
|
|
|
|
await webAppTransport.start();
|
|
|
|
if (backingServerTransport instanceof StdioClientTransport) {
|
|
backingServerTransport.stderr!.on("data", (chunk) => {
|
|
webAppTransport.send({
|
|
jsonrpc: "2.0",
|
|
method: "notifications/stderr",
|
|
params: {
|
|
content: chunk.toString(),
|
|
},
|
|
});
|
|
});
|
|
}
|
|
|
|
mcpProxy({
|
|
transportToClient: webAppTransport,
|
|
transportToServer: backingServerTransport,
|
|
onerror: (error) => {
|
|
console.error(error);
|
|
},
|
|
});
|
|
console.log("Set up MCP proxy");
|
|
} catch (error) {
|
|
console.error("Error in /sse route:", error);
|
|
res.status(500).json(error);
|
|
}
|
|
});
|
|
|
|
app.post("/message", async (req, res) => {
|
|
try {
|
|
const sessionId = req.query.sessionId;
|
|
console.log(`Received message for sessionId ${sessionId}`);
|
|
|
|
const transport = webAppTransports.find((t) => t.sessionId === sessionId);
|
|
if (!transport) {
|
|
res.status(404).end("Session not found");
|
|
return;
|
|
}
|
|
await transport.handlePostMessage(req, res);
|
|
} catch (error) {
|
|
console.error("Error in /message route:", error);
|
|
res.status(500).json(error);
|
|
}
|
|
});
|
|
|
|
app.get("/config", (req, res) => {
|
|
try {
|
|
const defaultEnvironment = getDefaultEnvironment();
|
|
res.json({
|
|
defaultEnvironment,
|
|
defaultCommand: values.env,
|
|
defaultArgs: values.args,
|
|
});
|
|
} catch (error) {
|
|
console.error("Error in /config route:", error);
|
|
res.status(500).json(error);
|
|
}
|
|
});
|
|
|
|
const PORT = process.env.PORT || 3000;
|
|
app.listen(PORT, () => { });
|