import { http } from '@google-cloud/functions-framework';
import { StreamableHTTPServerTransport } from '@modelcontextprotocol/sdk/server/streamableHttp.js';
import { createMcpServer } from './server.js';
// Create a single transport instance for stateless mode
const transport = new StreamableHTTPServerTransport({
sessionIdGenerator: undefined, // Stateless mode
});
// Create and connect the MCP server
const server = createMcpServer();
server.connect(transport);
http('mcpHandler', async (req, res) => {
// Enable CORS
res.set('Access-Control-Allow-Origin', '*');
res.set('Access-Control-Allow-Methods', 'GET, POST, HEAD, DELETE, OPTIONS');
res.set('Access-Control-Allow-Headers', 'Content-Type, Accept, Mcp-Session-Id');
res.set('Access-Control-Expose-Headers', 'Mcp-Session-Id');
if (req.method === 'OPTIONS') {
res.status(204).send('');
return;
}
const path = req.path || '/';
// Health check endpoint
if (path === '/health' && req.method === 'GET') {
res.json({ status: 'ok' });
return;
}
// MCP protocol version discovery (HEAD request to root)
if (path === '/' && req.method === 'HEAD') {
res.set('MCP-Protocol-Version', '2025-06-18');
res.status(200).send('');
return;
}
// Handle MCP requests at root path (Streamable HTTP transport)
if (path === '/' || path === '/mcp') {
if (req.method === 'GET' || req.method === 'POST' || req.method === 'DELETE') {
try {
await transport.handleRequest(req, res, req.body);
} catch (error) {
console.error('Error handling MCP request:', error);
if (!res.headersSent) {
res.status(500).json({ error: 'Internal server error' });
}
}
return;
}
}
// Default response
res.status(404).json({
error: 'Not found',
availableEndpoints: {
'/': 'GET/POST - MCP Streamable HTTP endpoint',
'/health': 'GET - Health check',
}
});
});
// For local development with stdio
if (process.env.MCP_STDIO === 'true') {
import('@modelcontextprotocol/sdk/server/stdio.js').then(({ StdioServerTransport }) => {
const stdioServer = createMcpServer();
const stdioTransport = new StdioServerTransport();
stdioServer.connect(stdioTransport);
console.error('MCP server running on stdio');
});
}
