如何使用TypeScript构建待办事项MCP服务器 - 包含身份验证、数据库和计费功能

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mkdir todo-mcp-server
cd todo-mcp-server
npm init -y

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npm install @modelcontextprotocol/sdk @neondatabase/serverless @kinde-oss/kinde-typescript-sdk express jsonwebtoken jwks-client express-session
npm install -D typescript @types/node @types/express @types/express-session tsx

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# Database
DATABASE_URL=postgresql://user:pass@host:port/db

# Kinde Authentication

KINDE_CLIENT_ID=your_client_id
KINDE_CLIENT_SECRET=your_client_secret

# Security
JWT_SECRET=your_secret_key

# Environment
NODE_ENV=development

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import { neon } from '@neondatabase/serverless';
import dotenv from 'dotenv';

dotenv.config();

const sql = neon(process.env.DATABASE_URL!);

async function setupDatabase() {
  console.log('Setting up database schema...');
  try {
    // 创建待办事项表
    await sql`
      CREATE TABLE IF NOT EXISTS todos (
        id SERIAL PRIMARY KEY,
        user_id TEXT NOT NULL,
        title TEXT NOT NULL,
        description TEXT,
        completed BOOLEAN DEFAULT FALSE,
        created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
        updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
      )
    `;

    // 创建用户表
    await sql`
      CREATE TABLE IF NOT EXISTS users (
        id SERIAL PRIMARY KEY,
        user_id TEXT UNIQUE NOT NULL,
        name TEXT,
        email TEXT,
        subscription_status TEXT DEFAULT 'free' CHECK (subscription_status IN ('free', 'active', 'cancelled')),
        plan TEXT DEFAULT 'free',
        free_todos_used INTEGER DEFAULT 0,
        created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
        updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
      )
    `;

    // 创建性能索引
    await sql`CREATE INDEX IF NOT EXISTS idx_todos_user_id ON todos(user_id)`;
    await sql`CREATE INDEX IF NOT EXISTS idx_todos_created_at ON todos(created_at)`;
    await sql`CREATE INDEX IF NOT EXISTS idx_users_user_id ON users(user_id)`;

    console.log('✅ Database schema created successfully!');
  } catch (error) {
    console.error('❌ Error setting up database:', error);
    process.exit(1);
  }
}

setupDatabase();

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import express from 'express';
import session from 'express-session';
import { createKindeServerClient, GrantType, SessionManager } from '@kinde-oss/kinde-typescript-sdk';
import jwt from 'jsonwebtoken';
import dotenv from 'dotenv';
import { neon } from '@neondatabase/serverless';

dotenv.config();
const app = express();
const sql = neon(process.env.DATABASE_URL!);

// 扩展会话类型
declare module 'express-session' {
  interface SessionData {
    accessToken?: string;
    idToken?: string;
    userInfo?: any;
    userName?: string;
    userEmail?: string;
  }
}

// 会话配置
app.use(session({
  secret: process.env.JWT_SECRET || 'your_jwt_secret_key',
  resave: true,
  saveUninitialized: true,
  cookie: { 
    secure: false,
    maxAge: 7 * 24 * 60 * 60 * 1000, // 7天
    httpOnly: true,
    sameSite: 'lax'
  }
}));

// 创建会话管理器
const createSessionManager = (req: any): SessionManager => ({
  getSessionItem: async (key: string) => req.session?.[key],
  setSessionItem: async (key: string, value: any) => {
    if (!req.session) req.session = {};
    req.session[key] = value;
  },
  removeSessionItem: async (key: string) => {
    if (req.session) delete req.session[key];
  },
  destroySession: async () => {
    req.session = {};
  }
});

// 创建Kinde客户端
const kindeClient = createKindeServerClient(GrantType.AUTHORIZATION_CODE, {

  clientId: process.env.KINDE_CLIENT_ID!,
  clientSecret: process.env.KINDE_CLIENT_SECRET!,
  redirectURL: 'http://localhost:3000/callback',
  logoutRedirectURL: 'http://localhost:3000',
});

// 路由定义
app.get('/', (req, res) => {
  const token = req.session?.accessToken;
  const userInfo = req.session?.userInfo;

  if (token) {
    res.send(`Logged in as ${req.session.userName}`);
  } else {
    res.send('<a href="/login">Login with Kinde</a>');
  }
});

app.get('/login', async (req, res) => {
  try {
    const sessionManager = createSessionManager(req);
    const loginUrl = await kindeClient.login(sessionManager);
    res.redirect(loginUrl.toString());
  } catch (error) {
    console.error('Login error:', error);
    res.status(500).send('Login failed');
  }
});

app.get('/callback', async (req, res) => {
  try {
    // 处理OAuth回调
    const fullUrl = `http://${req.headers.host}${req.url}`;
    const url = new URL(fullUrl);
    const code = url.searchParams.get('code');

    // 交换令牌

      method: 'POST',
      headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
      body: new URLSearchParams({
        grant_type: 'authorization_code',
        client_id: process.env.KINDE_CLIENT_ID!,
        client_secret: process.env.KINDE_CLIENT_SECRET!,
        code: code!,
        redirect_uri: 'http://localhost:3000/callback',
      }),
    });

    const tokenData = await tokenResponse.json();
    
    // 存储令牌到会话
    req.session.accessToken = tokenData.access_token;
    req.session.idToken = tokenData.id_token;
    req.session.userInfo = tokenData;

    // 解码JWT并存储用户信息
    const user = JSON.parse(Buffer.from(tokenData.id_token.split('.')[1], 'base64').toString());
    const userId = user.sub;
    const userName = user.given_name || user.name || 'User';
    const userEmail = user.email || 'user@example.com';

    req.session.userName = userName;
    req.session.userEmail = userEmail;

    // 在数据库中创建或更新用户
    const existingUser = await sql`SELECT * FROM users WHERE user_id = ${userId}`;
    if (existingUser.length === 0) {
      await sql`
        INSERT INTO users (user_id, name, email, subscription_status, plan, free_todos_used)
        VALUES (${userId}, ${userName}, ${userEmail}, 'free', 'free', 0)
      `;
    } else {
      await sql`
        UPDATE users 
        SET name = ${userName}, email = ${userEmail}
        WHERE user_id = ${userId}
      `;
    }

    res.redirect('/');
  } catch (error) {
    console.error('Callback error:', error);
    res.status(500).send('Authentication failed');
  }
});

app.get('/logout', async (req, res) => {
  try {
    req.session.destroy((err) => {
      if (err) {
        console.log('Session destroy error:', err);
      }
      res.redirect('/');
    });
  } catch (error) {
    console.error('Logout error:', error);
    res.status(500).send('Logout failed');
  }
});

app.listen(3000, () => {
  console.log('Auth server running on http://localhost:3000');
});

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import { Server } from '@modelcontextprotocol/sdk/server/index.js';
import { StdioServerTransport } from '@modelcontextprotocol/sdk/server/stdio.js';
import { CallToolRequestSchema, ListToolsRequestSchema } from '@modelcontextprotocol/sdk/types.js';
import { neon } from '@neondatabase/serverless';
import jwt from 'jsonwebtoken';
import fs from 'fs';
import path from 'path';

const sql = neon(process.env.DATABASE_URL!);
const TOKEN_FILE = '.auth-token';

// 令牌管理函数
function getStoredToken(): string | null {
  try {
    if (fs.existsSync(TOKEN_FILE)) {
      return fs.readFileSync(TOKEN_FILE, 'utf8').trim();
    }
  } catch (error) {
    console.error('Error reading token file:', error);
  }
  return null;
}

function storeToken(token: string): void {
  try {
    fs.writeFileSync(TOKEN_FILE, token);
  } catch (error) {
    console.error('Error storing token:', error);
  }
}

function decodeJWT(token: string): any {
  try {
    return jwt.decode(token);
  } catch (error) {
    console.error('Error decoding JWT:', error);
    return null;
  }
}

// 计费状态检查
async function getKindeBillingStatus(userId: string, accessToken: string): Promise<{ plan: string; features: any; canCreate: boolean; reason?: string }> {
  try {
    const decoded = jwt.decode(accessToken) as any;
    const subscription = await sql`SELECT * FROM users WHERE user_id = ${userId}`;

    if (subscription.length === 0) {
      await sql`
        INSERT INTO users (user_id, name, email, subscription_status, plan, free_todos_used)
        VALUES (${userId}, ${decoded.given_name || decoded.name || 'User'}, ${decoded.email || 'user@example.com'}, 'free', 'free', 0)
      `;
    }

    const freeTodosUsed = subscription.length > 0 ? subscription[0].free_todos_used : 0;

    if (freeTodosUsed < 1) {
      return {
        plan: 'free',
        features: { maxTodos: 1, used: freeTodosUsed },
        canCreate: true,
        reason: `Free tier - ${1 - freeTodosUsed} todo remaining`
      };
    }

    return {
      plan: 'free',
      features: { maxTodos: 1, used: freeTodosUsed },
      canCreate: false,
      reason: 'You have used your free todo. Please upgrade your plan.'
    };
  } catch (error) {
    console.error('Error checking Kinde billing:', error);
    return {
      plan: 'free',
      features: { maxTodos: 1 },
      canCreate: false,
      reason: 'Error checking billing status'
    };
  }
}

async function canCreateTodo(userId: string, accessToken: string): Promise<boolean> {
  const billingStatus = await getKindeBillingStatus(userId, accessToken);
  return billingStatus.canCreate;
}

// 初始化MCP服务器
const server = new Server(
  {
    name: 'todo-mcp-server',
    version: '1.0.0',
  },
  {
    capabilities: {
      tools: {},
    },
  }
);

// 注册工具
server.setRequestHandler(ListToolsRequestSchema, async () => {
  return {
    tools: [
      {
        name: 'login',
        description: 'Get authentication URL for Kinde login',
        inputSchema: {
          type: 'object',
          properties: {},
        },
      },
      {
        name: 'save_token',
        description: 'Save authentication token for future requests',
        inputSchema: {
          type: 'object',
          properties: {
            token: {
              type: 'string',
              description: 'JWT token from Kinde authentication',
            },
          },
          required: ['token'],
        },
      },
      {
        name: 'list_todos',
        description: 'List all todos for the authenticated user',
        inputSchema: {
          type: 'object',
          properties: {},
        },
      },
      {
        name: 'create_todo',
        description: 'Create a new todo item',
        inputSchema: {
          type: 'object',
          properties: {
            title: {
              type: 'string',
              description: 'Title of the todo',
            },
            description: {
              type: 'string',
              description: 'Description of the todo',
            },
            completed: {
              type: 'boolean',
              description: 'Whether the todo is completed',
            },
          },
          required: ['title'],
        },
      },
      {
        name: 'update_todo',
        description: 'Update an existing todo item',
        inputSchema: {
          type: 'object',
          properties: {
            todoId: {
              type: 'number',
              description: 'ID of the todo to update',
            },
            title: {
              type: 'string',
              description: 'New title of the todo',
            },
            description: {
              type: 'string',
              description: 'New description of the todo',
            },
            completed: {
              type: 'boolean',
              description: 'New completion status',
            },
          },
          required: ['todoId'],
        },
      },
      {
        name: 'delete_todo',
        description: 'Delete a todo item',
        inputSchema: {
          type: 'object',
          properties: {
            todoId: {
              type: 'number',
              description: 'ID of the todo to delete',
            },
          },
          required: ['todoId'],
        },
      },
      {
        name: 'refresh_billing_status',
        description: 'Refresh and check current billing status',
        inputSchema: {
          type: 'object',
          properties: {},
        },
      },
      {
        name: 'logout',
        description: 'Clear authentication token and logout',
        inputSchema: {
          type: 'object',
          properties: {},
        },
      },
    ],
  };
});

// 工具处理器
server.setRequestHandler(CallToolRequestSchema, async (request) => {
  const { name, arguments: args } = request.params;

  switch (name) {
    case 'login': {
      return {
        content: [
          {
            type: 'text',
            text: `🔐 **Authentication Required**

To use this MCP server, you need to authenticate with Kinde:

1. **Open your browser** and go to: http://localhost:3000
2. **Click "Login with Kinde"** to authenticate
3. **Copy your ID Token** from the page
4. **Use the save_token tool** to store it

After authentication, you can use commands like:
- \`list todos\` - List your todos
- \`create todo\` - Create a new todo
- \`refresh billing status\` - Check your plan status`,
          },
        ],
      };
    }

    case 'save_token': {
      const { token } = args as { token: string };
      storeToken(token);
      return {
        content: [
          {
            type: 'text',
            text: '✅ Token saved successfully! You can now use commands like "list todos" and "create todo" without providing the token each time.',
          },
        ],
      };
    }

    case 'list_todos': {
      const token = getStoredToken();
      if (!token) {
        return {
          content: [
            {
              type: 'text',
              text: '❌ No authentication token found. Please login first.',
            },
          ],
        };
      }

      const decoded = decodeJWT(token);
      if (!decoded || !decoded.sub) {
        return {
          content: [
            {
              type: 'text',
              text: '❌ Invalid token. Please login again.',
            },
          ],
        };
      }

      const todos = await sql`
        SELECT * FROM todos 
        WHERE user_id = ${decoded.sub} 
        ORDER BY created_at DESC
      `;

      if (todos.length === 0) {
        return {
          content: [
            {
              type: 'text',
              text: '📝 No todos found. Create your first todo using "create todo"!',
            },
          ],
        };
      }

      const todosList = todos.map((todo: any) => 
        `**${todo.id}.** ${todo.title}${todo.description ? ` - ${todo.description}` : ''} ${todo.completed ? '✅' : '⏳'}`
      ).join('\n');

      return {
        content: [
          {
            type: 'text',
            text: `📝 **Your Todos (${todos.length}):**\n\n${todosList}`,
          },
        ],
      };
    }

    case 'create_todo': {
      const token = getStoredToken();
      if (!token) {
        return {
          content: [
            {
              type: 'text',
              text: '❌ No authentication token found. Please login first.',
            },
          ],
        };
      }

      const decoded = decodeJWT(token);
      if (!decoded || !decoded.sub) {
        return {
          content: [
            {
              type: 'text',
              text: '❌ Invalid token. Please login again.',
            },
          ],
        };
      }

      const { title, description, completed } = args as { 
        title: string; 
        description?: string; 
        completed?: boolean; 
      };

      // 检查计费状态
      const canCreate = await canCreateTodo(decoded.sub, token);
      if (!canCreate) {
        const billingStatus = await getKindeBillingStatus(decoded.sub, token);
        return {
          content: [
            {
              type: 'text',
              text: `🚫 **Cannot create todo**\n\n${billingStatus.reason}`,
            },
          ],
        };
      }

      const result = await sql`
        INSERT INTO todos (user_id, title, description, completed)
        VALUES (${decoded.sub}, ${title}, ${description || null}, ${completed || false})
        RETURNING *
      `;

      // 更新免费待办事项使用计数
      await sql`
        UPDATE users 
        SET free_todos_used = free_todos_used + 1 
        WHERE user_id = ${decoded.sub}
      `;

      return {
        content: [
          {
            type: 'text',
            text: JSON.stringify({
              success: true,
              todoId: result[0].id,
              message: 'Todo created successfully',
              title: result[0].title,
              description: result[0].description,
              completed: result[0].completed
            }, null, 2),
          },
        ],
      };
    }

    case 'update_todo': {
      const token = getStoredToken();
      if (!token) {
        return {
          content: [
            {
              type: 'text',
              text: '❌ No authentication token found. Please login first.',
            },
          ],
        };
      }

      const decoded = decodeJWT(token);
      if (!decoded || !decoded.sub) {
        return {
          content: [
            {
              type: 'text',
              text: '❌ Invalid token. Please login again.',
            },
          ],
        };
      }

      const { todoId, title, description, completed } = args as { 
        todoId: number; 
        title?: string; 
        description?: string; 
        completed?: boolean; 
      };

      const result = await sql`
        UPDATE todos 
        SET 
          title = COALESCE(${title || null}, title),
          description = COALESCE(${description || null}, description),
          completed = COALESCE(${completed !== undefined ? completed : null}, completed),
          updated_at = CURRENT_TIMESTAMP
        WHERE id = ${todoId} AND user_id = ${decoded.sub}
        RETURNING *
      `;

      if (result.length === 0) {
        return {
          content: [
            {
              type: 'text',
              text: '❌ Todo not found or you do not have permission to update it.',
            },
          ],
        };
      }

      return {
        content: [
          {
            type: 'text',
            text: JSON.stringify({
              success: true,
              message: 'Todo updated successfully',
              todo: result[0]
            }, null, 2),
          },
        ],
      };
    }

    case 'delete_todo': {
      const token = getStoredToken();
      if (!token) {
        return {
          content: [
            {
              type: 'text',
              text: '❌ No authentication token found. Please login first.',
            },
          ],
        };
      }

      const decoded = decodeJWT(token);
      if (!decoded || !decoded.sub) {
        return {
          content: [
            {
              type: 'text',
              text: '❌ Invalid token. Please login again.',
            },
          ],
        ];
      }

      const { todoId } = args as { todoId: number };

      const result = await sql`
        DELETE FROM todos 
        WHERE id = ${todoId} AND user_id = ${decoded.sub}
        RETURNING *
      `;

      if (result.length === 0) {
        return {
          content: [
            {
              type: 'text',
              text: '❌ Todo not found or you do not have permission to delete it.',
            },
          ],
        };
      }

      return {
        content: [
          {
            type: 'text',
            text: JSON.stringify({
              success: true,
              message: 'Todo deleted successfully',
              deletedTodo: result[0]
            }, null, 2),
          },
        ],
      };
    }

    case 'refresh_billing_status': {
      const token = getStoredToken();
      if (!token) {
        return {
          content: [
            {
              type: 'text',
              text: '❌ No authentication token found. Please login first.',
            },
          ],
        };
      }

      const decoded = decodeJWT(token);
      if (!decoded || !decoded.sub) {
        return {
          content: [
            {
              type: 'text',
              text: '❌ Invalid token. Please login again.',
            },
          ],
        };
      }

      const billingStatus = await getKindeBillingStatus(decoded.sub, token);

      return {
        content: [
          {
            type: 'text',
            text: JSON.stringify({
              success: true,
              message: 'Billing status refreshed successfully!',
              kindeBilling: {
                plan: billingStatus.plan,
                features: billingStatus.features,
                canCreate: billingStatus.canCreate,
                reason: billingStatus.reason,
                lastChecked: new Date().toISOString()
              }
            }, null, 2),
          },
        ],
      };
    }

    case 'logout': {
      try {
        if (fs.existsSync(TOKEN_FILE)) {
          fs.unlinkSync(TOKEN_FILE);
        }
        return {
          content: [
            {
              type: 'text',
              text: '✅ Logged out successfully. Authentication token cleared.',
            },
          ],
        };
      } catch (error) {
        return {
          content: [
            {
              type: 'text',

            },
          ],
        };
      }
    }

    default:
      throw new Error(`Unknown tool: ${name}`);
  }
});

// 启动服务器
async function main() {
  const transport = new StdioServerTransport();
  await server.connect(transport);
  console.error('Todo MCP server running on stdio');
}

main().catch((error) => {
  console.error('Fatal error in main():', error);
  process.exit(1);
});

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# 终端1: 启动MCP服务器
npm run dev

# 终端2: 启动Kinde认证服务器
npm run auth-server

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{
  "mcpServers": {
    "todo-mcp-server": {
      "command": "node",
      "args": ["dist/server.js"],
      "cwd": "/path/to/your/todo-mcp-server",
      "env": {
        "DATABASE_URL": "your-neon-connection-string",

        "KINDE_CLIENT_ID": "your-client-id",
        "KINDE_CLIENT_SECRET": "your-client-secret",
        "JWT_SECRET": "your-jwt-secret-key",
        "NODE_ENV": "development"
      }
    }
  }
}

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┌─────────────────┐    ┌──────────────────┐    ┌─────────────────┐
│   Cursor IDE    │    │   MCP Server     │    │  Kinde Auth     │
│                 │◄──►│                  │◄──►│   Server        │
│ - MCP Tools     │    │ - Todo CRUD      │    │ - OAuth Flow    │
│ - Chat Interface│    │ - Billing Check  │    │ - Token Storage │
└─────────────────┘    └──────────────────┘    └─────────────────┘
                                │
                                ▼
                       ┌─────────────────┐
                       │ Neon PostgreSQL │
                       │                 │
                       │ - Users Table   │
                       │ - Todos Table   │
                       │ - Billing Data  │
                       └─────────────────┘

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用户输入 
   → MCP服务器 
      → 身份验证检查
         → 计费检查
            → 数据库操作
               → 响应