使用 Cursor 构建 API：REST、GraphQL 和 FastAPI

构建健壮的 API 需要仔细规划、一致的模式和彻底的测试。Cursor 的 AI 能力可以加速 API 开发的每个阶段，从搭建端点到生成 OpenAPI 文档。本指南涵盖 REST、GraphQL 和 FastAPI 工作流。

前置条件

在开始之前：

• 安装 Cursor（建议使用 Pro 计划）
• 安装 Node.js 或 Python
• 熟悉 HTTP 概念和 JSON

REST API 开发

项目脚手架

让 Cursor 搭建一个完整的 REST API：

使用 Express.js 创建一个 REST API，包含：
- TypeScript
- 路由处理器位于 src/routes/
- 日志和错误处理中间件
- 使用 Zod 进行输入验证
- JWT 认证
- 速率限制
- Swagger 文档

Express.js 路由结构

// src/routes/users.ts
import { Router } from 'express';
import { z } from 'zod';
import { authenticate } from '../middleware/auth';
import { validate } from '../middleware/validate';

const router = Router();

const createUserSchema = z.object({
  email: z.string().email(),
  name: z.string().min(2).max(100),
  password: z.string().min(8),
});

router.post(
  '/',
  authenticate,
  validate(createUserSchema),
  async (req, res, next) => {
    try {
      const user = await createUser(req.body);
      res.status(201).json({
        success: true,
        data: user,
      });
    } catch (error) {
      next(error);
    }
  }
);

router.get('/:id', authenticate, async (req, res, next) => {
  try {
    const user = await getUserById(req.params.id);
    if (!user) {
      return res.status(404).json({
        success: false,
        error: 'User not found',
      });
    }
    res.json({ success: true, data: user });
  } catch (error) {
    next(error);
  }
});

export default router;

统一错误处理

// src/middleware/errorHandler.ts
import { Request, Response, NextFunction } from 'express';

export class AppError extends Error {
  constructor(
    public statusCode: number,
    public message: string,
    public isOperational = true
  ) {
    super(message);
    Object.setPrototypeOf(this, AppError.prototype);
  }
}

export const errorHandler = (
  err: Error,
  req: Request,
  res: Response,
  next: NextFunction
) => {
  if (err instanceof AppError) {
    return res.status(err.statusCode).json({
      success: false,
      error: err.message,
    });
  }

  console.error('Unexpected error:', err);
  res.status(500).json({
    success: false,
    error: 'Internal server error',
  });
};

使用 Cursor 开发 FastAPI

创建 FastAPI 端点

# main.py
from fastapi import FastAPI, HTTPException, Depends, status
from fastapi.security import OAuth2PasswordBearer
from pydantic import BaseModel, EmailStr
from typing import List, Optional
import uvicorn

app = FastAPI(
    title="My API",
    description="A production-ready API built with FastAPI",
    version="1.0.0",
)

oauth2_scheme = OAuth2PasswordBearer(tokenUrl="token")

# Pydantic 模型
class UserCreate(BaseModel):
    email: EmailStr
    name: str
    password: str

class UserResponse(BaseModel):
    id: int
    email: str
    name: str

    class Config:
        from_attributes = True

# 内存存储（替换为数据库）
users_db = {}
user_counter = 0

@app.post(
    "/users",
    response_model=UserResponse,
    status_code=status.HTTP_201_CREATED,
    tags=["users"],
)
async def create_user(user: UserCreate):
    global user_counter
    user_counter += 1
    new_user = {
        "id": user_counter,
        "email": user.email,
        "name": user.name,
    }
    users_db[user_counter] = new_user
    return new_user

@app.get(
    "/users/{user_id}",
    response_model=UserResponse,
    tags=["users"],
)
async def get_user(user_id: int):
    if user_id not in users_db:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="User not found",
        )
    return users_db[user_id]

@app.get("/users", response_model=List[UserResponse], tags=["users"])
async def list_users(
    skip: int = 0,
    limit: int = 100,
):
    return list(users_db.values())[skip : skip + limit]

if __name__ == "__main__":
    uvicorn.run(app, host="0.0.0.0", port=8000)

依赖注入

# dependencies.py
from fastapi import Depends, HTTPException, status
from sqlalchemy.orm import Session
from database import SessionLocal

async def get_db():
    db = SessionLocal()
    try:
        yield db
    finally:
        db.close()

async def get_current_user(token: str = Depends(oauth2_scheme)):
    user = verify_token(token)
    if not user:
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail="Invalid authentication",
        )
    return user

# 用法
@app.get("/items")
async def read_items(
    db: Session = Depends(get_db),
    current_user: User = Depends(get_current_user),
):
    return db.query(Item).filter(Item.owner_id == current_user.id).all()

GraphQL API 开发

Apollo Server 设置

// src/schema.ts
import { gql } from 'apollo-server-express';

export const typeDefs = gql`
  type User {
    id: ID!
    email: String!
    name: String!
    posts: [Post!]!
  }

  type Post {
    id: ID!
    title: String!
    content: String!
    author: User!
  }

  type Query {
    users: [User!]!
    user(id: ID!): User
    posts: [Post!]!
    post(id: ID!): Post
  }

  type Mutation {
    createUser(email: String!, name: String!, password: String!): User!
    createPost(title: String!, content: String!, authorId: ID!): Post!
  }
`;

使用 Cursor 的解析器

// src/resolvers.ts
export const resolvers = {
  Query: {
    users: async (_, __, { dataSources }) => {
      return dataSources.userAPI.getAllUsers();
    },
    user: async (_, { id }, { dataSources }) => {
      return dataSources.userAPI.getUserById(id);
    },
  },
  User: {
    posts: async (parent, _, { dataSources }) => {
      return dataSources.postAPI.getPostsByAuthor(parent.id);
    },
  },
  Mutation: {
    createUser: async (_, args, { dataSources }) => {
      return dataSources.userAPI.createUser(args);
    },
  },
};

GraphQL 模式设计

使用 Cursor 从数据库模式生成 GraphQL 模式。粘贴您的 Prisma 模式并请求相应的 GraphQL 类型定义。

认证和授权

JWT 实现

// src/utils/jwt.ts
import jwt from 'jsonwebtoken';
import bcrypt from 'bcrypt';

const JWT_SECRET = process.env.JWT_SECRET!;
const SALT_ROUNDS = 12;

export const hashPassword = async (password: string): Promise<string> => {
  return bcrypt.hash(password, SALT_ROUNDS);
};

export const comparePassword = async (
  password: string,
  hash: string
): Promise<boolean> => {
  return bcrypt.compare(password, hash);
};

export const generateToken = (payload: object): string => {
  return jwt.sign(payload, JWT_SECRET, { expiresIn: '24h' });
};

export const verifyToken = (token: string): any => {
  return jwt.verify(token, JWT_SECRET);
};

中间件模式

// src/middleware/rateLimit.ts
import rateLimit from 'express-rate-limit';

export const apiLimiter = rateLimit({
  windowMs: 15 * 60 * 1000, // 15 分钟
  max: 100, // 每个 IP 每窗口限制 100 个请求
  message: {
    success: false,
    error: 'Too many requests, please try again later',
  },
  standardHeaders: true,
  legacyHeaders: false,
});

API 文档

FastAPI 的 OpenAPI

FastAPI 自动生成 OpenAPI 文档。访问地址：

• Swagger UI: /docs
• ReDoc: /redoc

Express.js 配合 Swagger

// src/config/swagger.ts
import swaggerJsdoc from 'swagger-jsdoc';

const options = {
  definition: {
    openapi: '3.0.0',
    info: {
      title: 'My API',
      version: '1.0.0',
      description: 'API documentation',
    },
    servers: [
      {
        url: 'http://localhost:3000/api',
      },
    ],
  },
  apis: ['./src/routes/*.ts'],
};

export const specs = swaggerJsdoc(options);

测试 API

集成测试示例

// tests/users.test.ts
import request from 'supertest';
import app from '../src/app';

describe('Users API', () => {
  describe('POST /users', () => {
    it('should create a new user', async () => {
      const response = await request(app)
        .post('/users')
        .send({
          email: '[email protected]',
          name: 'Test User',
          password: 'securePassword123',
        })
        .expect(201);

      expect(response.body.success).toBe(true);
      expect(response.body.data.email).toBe('[email protected]');
    });

    it('should reject invalid email', async () => {
      await request(app)
        .post('/users')
        .send({
          email: 'invalid-email',
          name: 'Test',
          password: 'password',
        })
        .expect(400);
    });
  });
});

API 设计最佳实践

实践	实现
版本控制	在 URL 中使用 /api/v1/ 前缀
分页	返回 { data, meta: { page, limit, total } }
过滤	使用查询参数：?status=active&sort=created_at
错误格式	一致的 { success: false, error: "message" }
速率限制	公共端点每 15 分钟 100 个请求
缓存	使用 ETag 头部和 Redis 进行响应缓存

常见 API 模式

仓库模式

// src/repositories/UserRepository.ts
export class UserRepository {
  async findById(id: string): Promise<User | null> {
    return prisma.user.findUnique({ where: { id } });
  }

  async findByEmail(email: string): Promise<User | null> {
    return prisma.user.findUnique({ where: { email } });
  }

  async create(data: CreateUserInput): Promise<User> {
    return prisma.user.create({ data });
  }

  async update(id: string, data: UpdateUserInput): Promise<User> {
    return prisma.user.update({ where: { id }, data });
  }

  async delete(id: string): Promise<void> {
    await prisma.user.delete({ where: { id } });
  }
}

环境配置

# .env
NODE_ENV=development
PORT=3000
DATABASE_URL=postgresql://user:pass@localhost:5432/myapp
JWT_SECRET=your-secret-key
REDIS_URL=redis://localhost:6379
RATE_LIMIT_MAX=100

快速参考

任务	Cursor 提示
生成 CRUD 端点	"为 Product 资源创建带有验证的 CRUD 端点"
添加认证	"为所有受保护路由添加 JWT 认证中间件"
创建 GraphQL 模式	"从此 Prisma 模式生成 GraphQL 类型"
编写测试	"为用户注册端点编写集成测试"
添加速率限制	"为 API 添加速率限制，认证和公共端点使用不同层级"

相关资源

• Cursor 数据库开发指南
• Cursor Docker 开发指南
• Cursor 测试指南

最后更新：2025 年 7 月