开发示例

🟢 Node.js 项目开发

用 Trae 构建 Node.js 后端服务，从 Express API 到命令行工具，AI 帮你写更好的代码。

示例一：Express + TypeScript API

Terminal — 项目初始化

mkdir node-api && cd node-api
npm init -y
npm install express cors
npm install -D typescript @types/node @types/express ts-node nodemon
npx tsc --init
trae .

Express 中间件 + 路由架构

Express + TypeScript

src/app.ts

import express, { Request, Response, NextFunction } from 'express'
import cors from 'cors'

const app = express()

// 中间件
app.use(cors())
app.use(express.json())
app.use(requestLogger)

// 请求日志中间件
function requestLogger(req: Request, res: Response, next: NextFunction) {
  const start = Date.now()
  res.on('finish', () => {
    const ms = Date.now() - start
    console.log(`${req.method} ${req.path} ${res.statusCode} ${ms}ms`)
  })
  next()
}

// 路由
const router = express.Router()

const items: { id: number; name: string; value: number }[] = []
let nextId = 1

router.get('/', (req, res) => {
  const { sort, order = 'asc' } = req.query
  let result = [...items]
  if (sort === 'value') {
    result.sort((a, b) => order === 'asc' ? a.value - b.value : b.value - a.value)
  }
  res.json({ data: result, total: result.length })
})

router.post('/', (req, res) => {
  const { name, value } = req.body
  if (!name || value === undefined) {
    return res.status(400).json({ error: 'name 和 value 必填' })
  }
  const item = { id: nextId++, name, value: Number(value) }
  items.push(item)
  res.status(201).json(item)
})

router.delete('/:id', (req, res) => {
  const id = Number(req.params.id)
  const idx = items.findIndex(i => i.id === id)
  if (idx === -1) return res.status(404).json({ error: '不存在' })
  items.splice(idx, 1)
  res.status(204).send()
})

app.use('/api/items', router)

// 全局错误处理
app.use((err: Error, req: Request, res: Response, _next: NextFunction) => {
  console.error(err)
  res.status(500).json({ error: '服务器内部错误' })
})

app.listen(3000, () => console.log('🚀 服务运行在 http://localhost:3000'))
export default app

示例二：命令行工具 (CLI)

cli.js — 文件批量重命名工具

#!/usr/bin/env node
const fs = require('fs')
const path = require('path')

const [,, dir = '.', pattern = '', replacement = ''] = process.argv

if (!pattern) {
  console.log('用法: node cli.js [目录] [查找] [替换]')
  console.log('示例: node cli.js ./images IMG img')
  process.exit(0)
}

const files = fs.readdirSync(dir)
let count = 0

files.forEach(file => {
  if (!file.includes(pattern)) return
  const newName = file.replaceAll(pattern, replacement)
  fs.renameSync(path.join(dir, file), path.join(dir, newName))
  console.log(`✓ ${file} → ${newName}`)
  count++
})

console.log(`\n完成：重命名了 ${count} 个文件`)

示例三：WebSocket 实时通信

ws-server.js

const { WebSocketServer } = require('ws')

const wss = new WebSocketServer({ port: 8080 })
const clients = new Map()

wss.on('connection', (ws) => {
  const id = Date.now().toString(36)
  clients.set(id, ws)
  console.log(`客户端 ${id} 已连接，当前 ${clients.size} 人在线`)

  // 广播上线通知
  broadcast({ type: 'join', id, online: clients.size }, id)

  ws.on('message', (data) => {
    try {
      const msg = JSON.parse(data.toString())
      broadcast({ ...msg, from: id, time: new Date().toISOString() })
    } catch { /* 忽略非 JSON 消息 */ }
  })

  ws.on('close', () => {
    clients.delete(id)
    broadcast({ type: 'leave', id, online: clients.size })
  })
})

function broadcast(data, excludeId = null) {
  const msg = JSON.stringify(data)
  clients.forEach((ws, id) => {
    if (id !== excludeId && ws.readyState === 1) ws.send(msg)
  })
}

console.log('WebSocket 服务运行在 ws://localhost:8080')

💡

在 Trae 中开发 Node.js 时，安装 REST Client 插件，可以直接在 .http 文件中测试 API，无需切换到 Postman。