#!/usr/bin/env node
import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
import { createServer } from "./funding-assistant.js";
import express from "express";
import { randomUUID } from "crypto";
const app = express();
app.use(express.json());
async function main() {
const { server, cleanup } = createServer();
// Transport configuration from environment variables
const allowedHosts = process.env.MCP_ALLOWED_HOSTS?.split(',') || ['127.0.0.1', 'localhost'];
const allowedOrigins = process.env.MCP_ALLOWED_ORIGINS?.split(',') || ['*'];
const enableSessions = process.env.MCP_ENABLE_SESSIONS !== 'false'; // Default to true
const enableDnsRebinding = process.env.MCP_ENABLE_DNS_REBINDING !== 'false'; // Default to true
const PORT = process.env.PORT || 3500;
console.log(`Transport Configuration:`);
console.log(`- Sessions enabled: ${enableSessions}`);
console.log(`- DNS rebinding protection: ${enableDnsRebinding}`);
console.log(`- Allowed hosts: ${allowedHosts.join(', ')}`);
console.log(`- Allowed origins: ${allowedOrigins.join(', ')}`);
console.log(`- Port: ${PORT}`);
// Create streamable HTTP transport
const transport = new StreamableHTTPServerTransport({
sessionIdGenerator: enableSessions ? () => randomUUID() : undefined,
onsessioninitialized: (sessionId) => {
console.log(`MCP session initialized: ${sessionId}`);
},
onsessionclosed: (sessionId) => {
console.log(`MCP session closed: ${sessionId}`);
},
enableDnsRebindingProtection: enableDnsRebinding,
allowedHosts,
allowedOrigins
});
// Connect the server to the transport with error handling
try {
await server.connect(transport);
console.log(`✅ MCP server connected to StreamableHTTP transport successfully`);
} catch (error) {
console.error(`❌ Failed to connect MCP server to transport:`, error);
process.exit(1);
}
// Health check endpoint
app.get("/health", (req, res) => {
res.json({
status: "ok",
timestamp: new Date().toISOString(),
transport: "StreamableHTTP",
version: process.env.npm_package_version || "unknown"
});
});
// Configuration endpoint (for debugging)
app.get("/config", (req, res) => {
res.json({
server: {
name: "@fluentlab/funding-assistant",
version: process.env.npm_package_version || "unknown",
transport: "StreamableHTTPServerTransport"
},
configuration: {
sessionsEnabled: enableSessions,
dnsRebindingProtection: enableDnsRebinding,
allowedHosts: allowedHosts,
allowedOrigins: allowedOrigins,
port: PORT
},
endpoints: {
health: "/health",
config: "/config",
mcp: "/mcp",
methods: ["GET", "POST", "DELETE", "OPTIONS"]
},
timestamp: new Date().toISOString()
});
});
// Handle MCP POST requests
app.post("/mcp", async (req, res) => {
const requestId = randomUUID().substring(0, 8);
console.log(`[${requestId}] Received MCP POST request`);
try {
// Set CORS headers for all origins
const corsOrigin = req.headers.origin && allowedOrigins.includes('*')
? req.headers.origin
: allowedOrigins[0];
res.header("Access-Control-Allow-Origin", corsOrigin || "*");
res.header("Access-Control-Allow-Methods", "GET, POST, DELETE, OPTIONS");
res.header("Access-Control-Allow-Headers", "Content-Type, Authorization");
res.header("Access-Control-Allow-Credentials", "true");
// Let the streamable HTTP transport handle the request
console.log(`[${requestId}] Processing request through transport`);
await transport.handleRequest(req, res, req.body);
console.log(`[${requestId}] Request completed`);
} catch (error) {
console.error(`[${requestId}] MCP request error:`, error);
if (!res.headersSent) {
res.status(500).json({
error: "Internal server error",
details: error instanceof Error ? error.message : String(error),
requestId
});
}
}
});
// Handle MCP GET requests (for SSE streams)
app.get("/mcp", async (req, res) => {
const requestId = randomUUID().substring(0, 8);
console.log(`[${requestId}] Received MCP GET request for SSE stream`);
try {
// Set CORS headers
const corsOrigin = req.headers.origin && allowedOrigins.includes('*')
? req.headers.origin
: allowedOrigins[0];
res.header("Access-Control-Allow-Origin", corsOrigin || "*");
res.header("Access-Control-Allow-Methods", "GET, POST, DELETE, OPTIONS");
res.header("Access-Control-Allow-Headers", "Content-Type, Authorization");
res.header("Access-Control-Allow-Credentials", "true");
// Let the streamable HTTP transport handle the request
console.log(`[${requestId}] Processing SSE stream through transport`);
await transport.handleRequest(req, res, req.body);
console.log(`[${requestId}] SSE stream established`);
} catch (error) {
console.error(`[${requestId}] MCP SSE request error:`, error);
if (!res.headersSent) {
res.status(500).json({
error: "Internal server error",
details: error instanceof Error ? error.message : String(error),
requestId
});
}
}
});
// Handle MCP DELETE requests (for session termination)
app.delete("/mcp", async (req, res) => {
const requestId = randomUUID().substring(0, 8);
console.log(`[${requestId}] Received MCP DELETE request for session termination`);
try {
// Set CORS headers
const corsOrigin = req.headers.origin && allowedOrigins.includes('*')
? req.headers.origin
: allowedOrigins[0];
res.header("Access-Control-Allow-Origin", corsOrigin || "*");
res.header("Access-Control-Allow-Methods", "GET, POST, DELETE, OPTIONS");
res.header("Access-Control-Allow-Headers", "Content-Type, Authorization");
res.header("Access-Control-Allow-Credentials", "true");
// Let the streamable HTTP transport handle the request
console.log(`[${requestId}] Processing session termination through transport`);
await transport.handleRequest(req, res, req.body);
console.log(`[${requestId}] Session terminated`);
} catch (error) {
console.error(`[${requestId}] MCP DELETE request error:`, error);
if (!res.headersSent) {
res.status(500).json({
error: "Internal server error",
details: error instanceof Error ? error.message : String(error),
requestId
});
}
}
});
// Handle OPTIONS for CORS
app.options("/mcp", (req, res) => {
res.header("Access-Control-Allow-Origin", "*");
res.header("Access-Control-Allow-Methods", "GET, POST, DELETE, OPTIONS");
res.header("Access-Control-Allow-Headers", "Content-Type, Authorization");
res.status(200).end();
});
const httpServer = app.listen(PORT, () => {
console.log(`🚀 StreamableHTTP MCP Server is running on port ${PORT}`);
console.log(`📋 Endpoints:`);
console.log(` - Health check: http://localhost:${PORT}/health`);
console.log(` - Configuration: http://localhost:${PORT}/config`);
console.log(` - MCP endpoint: http://localhost:${PORT}/mcp`);
console.log(`🔧 Transport: StreamableHTTPServerTransport`);
});
// Graceful shutdown
const shutdown = async () => {
console.log("Shutting down StreamableHTTP server...");
httpServer.close();
await cleanup();
await server.close();
process.exit(0);
};
process.on("SIGINT", shutdown);
process.on("SIGTERM", shutdown);
}
main().catch((error) => {
console.error("StreamableHTTP Server error:", error);
process.exit(1);
});
