cli.ts

import express from 'express';
import { Client } from '../src/client/index.js';
import { SSEClientTransport } from '../src/client/sse.js';
import { StdioClientTransport } from '../src/client/stdio.js';
import { Server } from '../src/server/index.js';
import { SSEServerTransport } from '../src/server/sse.js';
import { StdioServerTransport } from '../src/server/stdio.js';
import { ListResourcesResultSchema } from '../src/types.js';

async function runClient(url_or_command: string, args: string[]) {
    const client = new Client(
        {
            name: 'mcp-typescript test client',
            version: '0.1.0'
        },
        {
            capabilities: {
                sampling: {}
            }
        }
    );

    let clientTransport;

    let url: URL | undefined = undefined;
    try {
        url = new URL(url_or_command);
    } catch {
        // Ignore
    }

    if (url?.protocol === 'http:' || url?.protocol === 'https:') {
        clientTransport = new SSEClientTransport(new URL(url_or_command));
    } else if (url?.protocol === 'ws:' || url?.protocol === 'wss:') {
        throw new Error('WebSocket URLs are no longer supported. Use http(s) or stdio instead.');
    } else {
        clientTransport = new StdioClientTransport({
            command: url_or_command,
            args
        });
    }

    console.log('Connected to server.');

    await client.connect(clientTransport);
    console.log('Initialized.');

    await client.request({ method: 'resources/list' }, ListResourcesResultSchema);

    await client.close();
    console.log('Closed.');
}

async function runServer(port: number | null) {
    if (port !== null) {
        const app = express();

        let servers: Server[] = [];

        app.get('/sse', async (req, res) => {
            console.log('Got new SSE connection');

            const transport = new SSEServerTransport('/message', res);
            const server = new Server(
                {
                    name: 'mcp-typescript test server',
                    version: '0.1.0'
                },
                {
                    capabilities: {}
                }
            );

            servers.push(server);

            server.onclose = () => {
                console.log('SSE connection closed');
                servers = servers.filter(s => s !== server);
            };

            await server.connect(transport);
        });

        app.post('/message', async (req, res) => {
            console.log('Received message');

            const sessionId = req.query.sessionId as string;
            const transport = servers.map(s => s.transport as SSEServerTransport).find(t => t.sessionId === sessionId);
            if (!transport) {
                res.status(404).send('Session not found');
                return;
            }

            await transport.handlePostMessage(req, res);
        });

        app.listen(port, error => {
            if (error) {
                console.error('Failed to start server:', error);
                process.exit(1);
            }
            console.log(`Server running on http://localhost:${port}/sse`);
        });
    } else {
        const server = new Server(
            {
                name: 'mcp-typescript test server',
                version: '0.1.0'
            },
            {
                capabilities: {
                    prompts: {},
                    resources: {},
                    tools: {},
                    logging: {}
                }
            }
        );

        const transport = new StdioServerTransport();
        await server.connect(transport);

        console.log('Server running on stdio');
    }
}

const args = process.argv.slice(2);
const command = args[0];
switch (command) {
    case 'client':
        if (args.length < 2) {
            console.error('Usage: client <server_url_or_command> [args...]');
            process.exit(1);
        }

        runClient(args[1], args.slice(2)).catch(error => {
            console.error(error);
            process.exit(1);
        });

        break;

    case 'server': {
        const port = args[1] ? parseInt(args[1]) : null;
        runServer(port).catch(error => {
            console.error(error);
            process.exit(1);
        });

        break;
    }

    default:
        console.error('Unrecognized command:', command);
}