Node.js JWT认证教程

1. 项目介绍

JSON Web Token (JWT) 是一种安全的跨域身份验证解决方案，在现代Web应用中广泛使用。本教程将详细讲解如何在Node.js中实现JWT认证。

2. 项目准备

2.1 初始化项目

# 创建项目目录
mkdir nodejs-jwt-auth
cd nodejs-jwt-auth# 初始化项目
npm init -y# 安装依赖
npm install express jsonwebtoken bcryptjs body-parser

2.2 项目依赖说明

• express: Web应用框架
• jsonwebtoken: JWT生成与验证
• bcryptjs: 密码加密
• body-parser: 解析请求体

3. 项目结构

nodejs-jwt-auth/
│
├── config/
│   └── database.js
├── models/
│   └── user.js
├── middleware/
│   └── auth.js
├── routes/
│   └── auth.js
├── server.js
└── package.json

4. 详细实现

4.1 数据库配置 (config/database.js)

module.exports = {secret: 'your_jwt_secret_key',database: 'mongodb://localhost:27017/jwt-auth-demo'
};

4.2 用户模型 (models/user.js)

const mongoose = require('mongoose');
const bcrypt = require('bcryptjs');const UserSchema = new mongoose.Schema({username: {type: String,required: true,unique: true},password: {type: String,required: true}
});// 密码加密中间件
UserSchema.pre('save', function(next) {if (!this.isModified('password')) return next();bcrypt.genSalt(10, (err, salt) => {if (err) return next(err);bcrypt.hash(this.password, salt, (err, hash) => {if (err) return next(err);this.password = hash;next();});});
});// 密码验证方法
UserSchema.methods.comparePassword = function(candidatePassword) {return bcrypt.compareSync(candidatePassword, this.password);
};module.exports = mongoose.model('User', UserSchema);

4.3 认证中间件 (middleware/auth.js)

const jwt = require('jsonwebtoken');
const config = require('../config/database');module.exports = (req, res, next) => {const token = req.headers['authorization'];if (!token) {return res.status(403).json({ success: false, message: '未提供认证Token' });}jwt.verify(token, config.secret, (err, decoded) => {if (err) {return res.status(401).json({ success: false, message: 'Token无效' });}req.userId = decoded.id;next();});
};

4.4 路由 (routes/auth.js)

const express = require('express');
const jwt = require('jsonwebtoken');
const router = express.Router();
const User = require('../models/user');
const config = require('../config/database');
const authMiddleware = require('../middleware/auth');// 用户注册
router.post('/register', async (req, res) => {try {const { username, password } = req.body;const existingUser = await User.findOne({ username });if (existingUser) {return res.status(400).json({ success: false, message: '用户已存在' });}const user = new User({ username, password });await user.save();res.status(201).json({ success: true, message: '注册成功' });} catch (error) {res.status(500).json({ success: false, message: '服务器错误' });}
});// 用户登录
router.post('/login', async (req, res) => {try {const { username, password } = req.body;const user = await User.findOne({ username });if (!user) {return res.status(401).json({ success: false, message: '用户不存在' });}const isMatch = user.comparePassword(password);if (!isMatch) {return res.status(401).json({ success: false, message: '密码错误' });}const token = jwt.sign({ id: user._id }, config.secret, { expiresIn: '24h' });res.json({ success: true, token: `Bearer ${token}` });} catch (error) {res.status(500).json({ success: false, message: '服务器错误' });}
});// 受保护的路由
router.get('/profile', authMiddleware, async (req, res) => {try {const user = await User.findById(req.userId).select('-password');res.json({ success: true, user });} catch (error) {res.status(500).json({ success: false, message: '服务器错误' });}
});module.exports = router;

4.5 服务器入口 (server.js)

const express = require('express');
const mongoose = require('mongoose');
const bodyParser = require('body-parser');
const config = require('./config/database');
const authRoutes = require('./routes/auth');const app = express();// 数据库连接
mongoose.connect(config.database, {useNewUrlParser: true,useUnifiedTopology: true
});// 中间件
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: true }));// 路由
app.use('/api/auth', authRoutes);const PORT = process.env.PORT || 3000;
app.listen(PORT, () => {console.log(`服务器运行在 ${PORT} 端口`);
});

5. 使用说明

5.1 注册用户

POST /api/auth/register
{"username": "testuser","password": "123456"
}

5.2 用户登录

POST /api/auth/login
{"username": "testuser","password": "123456"
}

5.3 访问受保护路由

GET /api/auth/profile
Authorization: Bearer <token>

6. 安全建议

1. 使用HTTPS保护传输
2. 定期更新JWT密钥
3. 设置合理的Token过期时间
4. 对敏感操作进行二次验证

7. 注意事项

• 生产环境中应使用环境变量管理密钥
• 建议使用更强的加密算法
• 根据实际需求调整Token过期策略