文章目录
- 一、JWT是什么?
- 二、使用步骤
-
- 1.项目结构
- 2.相关依赖
- 3.数据库
- 4.相关代码
- 三、测试结果
一、JWT是什么?
在介绍JWT之前,我们先来回顾一下利用token进行用户身份验证的流程:
1、客户端使用用户名和密码请求登录
2、服务端收到请求,验证用户名和密码
3、验证成功后,服务端会签发一个token,再把这个token返回给客户端
4、客户端收到token后可以把它存储起来,比如放到cookie中
5、客户端每次向服务端请求资源时需要携带服务端签发的token,可以在cookie或者header中携带
6、服务端收到请求,然后去验证客户端请求里面带着的token,如果验证成功,就向客户端返回请求数据
这种基于token的认证方式相比传统的session认证方式更节约服务器资源,并且对移动端和分布式更加友好。其优点如下:
支持跨域访问:cookie是无法跨域的,而token由于没有用到cookie(前提是将token放到请求头中),所以跨域后不会存在信息丢失问题
无状态:token机制在服务端不需要存储session信息,因为token自身包含了所有登录用户的信息,所以可以减轻服务端压力
更适用CDN:可以通过内容分发网络请求服务端的所有资料
更适用于移动端:当客户端是非浏览器平台时,cookie是不被支持的,此时采用token认证方式会简单很多
无需考虑CSRF:由于不再依赖cookie,所以采用token认证方式不会发生CSRF,所以也就无需考虑CSRF的防御
而JWT就是上述流程当中token的一种具体实现方式,其全称是JSON Web Token,官网地址:https://jwt.io/
通俗地说,JWT的本质就是一个字符串,它是将用户信息保存到一个Json字符串中,然后进行编码后得到一个JWT token,并且这个JWT token带有签名信息,接收后可以校验是否被篡改,所以可以用于在各方之间安全地将信息作为Json对象传输。JWT的认证流程如下:
1、首先,前端通过Web表单将自己的用户名和密码发送到后端的接口,这个过程一般是一个POST请求。建议的方式是通过SSL加密的传输(HTTPS),从而避免敏感信息被嗅探
2、后端核对用户名和密码成功后,将包含用户信息的数据作为JWT的Payload,将其与JWT Header分别进行Base64编码拼接后签名,形成一个JWT Token,形成的JWT Token就是一个如同lll.zzz.xxx的字符串
3、后端将JWT Token字符串作为登录成功的结果返回给前端。前端可以将返回的结果保存在浏览器中,退出登录时删除保存的JWT Token即可
4、前端在每次请求时将JWT Token放入HTTP请求头中的Authorization属性中(解决XSS和XSRF问题)
5、后端检查前端传过来的JWT Token,验证其有效性,比如检查签名是否正确、是否过期、token的接收方是否是自己等等
6、验证通过后,后端解析出JWT Token中包含的用户信息,进行其他逻辑操作(一般是根据用户信息得到权限等),返回结果
最后:说白了,JWT:JSON Web Token,其实token就是一段字符串,由三部分组成:Header,Payload,Signature
二、使用步骤
1.项目结构
2.相关依赖
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.22</version>
</dependency>
<dependency>
<groupId>cn.hutool</groupId>
<artifactId>hutool-all</artifactId>
<version>5.7.21</version>
</dependency>
<dependency>
<groupId>com.baomidou</groupId>
<artifactId>mybatis-plus-boot-starter</artifactId>
<version>3.4.3.2</version>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.2.79</version>
</dependency>
<dependency>
<groupId>commons-beanutils</groupId>
<artifactId>commons-beanutils</artifactId>
<version>1.9.4</version>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.18.22</version>
</dependency>
<dependency>
<groupId>commons-io</groupId>
<artifactId>commons-io</artifactId>
<version>2.11.0</version>
</dependency>
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi-ooxml</artifactId>
<version>4.1.2</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.13.1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<version>2.3.8.RELEASE</version>
</dependency>
<dependency>
<groupId>com.auth0</groupId>
<artifactId>java-jwt</artifactId>
<version>3.18.3</version>
</dependency>
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-lang3</artifactId>
</dependency>
</dependencies>
3.数据库
这里进行测试,所以用户类只有用户名密码,自行创建
4.相关代码
1、annotation包
PassToken:
package com.geesun.annotation;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* @author :Mr.ZJW
* @date :Created 2022/2/28 10:26
* @description:用来跳过验证的 PassToken
*/
@Target({ElementType.METHOD, ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
public @interface PassToken {
boolean required() default true;
}
UserLoginToken:
package com.geesun.annotation;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* @author :Mr.ZJW
* @date :Created 2022/2/28 10:26
* @description:用于登录后才能操作的token
*/
/*RetentionPolicy.RUNTIME:这种类型的Annotations将被JVM保留,
所以他们能在运行时被JVM或其他使用反射机制的代码所读取和使用。*/
@Target({ElementType.METHOD, ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
public @interface UserLoginToken {
boolean required() default true;
}
2、common包
CodeMsg:
package com.geesun.common;
/**
* @author :Mr.ZJW
* @date :Created 2022/2/28 10:26
* @description:返回提示
*/
public class CodeMsg {
private int retCode;
private String message;
// 按照模块定义CodeMsg
// 通用异常
public static CodeMsg SUCCESS = new CodeMsg(0,"success");
public static CodeMsg SERVER_EXCEPTION = new CodeMsg(500100,"服务端异常");
public static CodeMsg PARAMETER_ISNULL = new CodeMsg(500101,"输入参数为空");
// 业务异常
public static CodeMsg USER_NOT_EXSIST = new CodeMsg(500102,"用户不存在");
public static CodeMsg ONLINE_USER_OVER = new CodeMsg(500103,"在线用户数超出允许登录的最大用户限制。");
public static CodeMsg SESSION_NOT_EXSIST = new CodeMsg(500104,"不存在离线session数据");
public static CodeMsg NOT_FIND_DATA = new CodeMsg(500105,"查找不到对应数据");
public static CodeMsg USER_OR_PASS_ERROR = new CodeMsg(500102,"账号或者密码错误,请重试!");
private CodeMsg(int retCode, String message) {
this.retCode = retCode;
this.message = message;
}
public int getRetCode() {
return retCode;
}
public String getMessage() {
return message;
}
public void setMessage(String message) {
this.message = message;
}
}
Result:
package com.geesun.common;
/**
* @author :Mr.ZJW
* @date :Created 2022/2/28 10:26
* @description:返回统一结果集
*/
public class Result<T> {
private String message;
private int retCode;
private T data;
private Result(T data) {
this.retCode = 200;
this.message = "成功";
this.data = data;
}
private Result(CodeMsg cm) {
if(cm == null){
return;
}
this.retCode = cm.getRetCode();
this.message = cm.getMessage();
}
/**
* 成功时候的调用
* @return
*/
public static <T> Result<T> success(T data){
return new Result<T>(data);
}
/**
* 成功,不需要传入参数
* @return
*/
@SuppressWarnings("unchecked")
public static <T> Result<T> success(){
return (Result<T>) success("");
}
/**
* 失败时候的调用
* @return
*/
public static <T> Result<T> error(CodeMsg cm){
return new Result<T>(cm);
}
/**
* 失败时候的调用,扩展消息参数
* @param cm
* @param msg
* @return
*/
public static <T> Result<T> error(CodeMsg cm,String msg){
cm.setMessage(cm.getMessage()+"--"+msg);
return new Result<T>(cm);
}
public T getData() {
return data;
}
public String getMessage() {
return message;
}
public int getRetCode() {
return retCode;
}
}
3、config包
InterceptorConfig:
package com.geesun.config;
import com.geesun.Interceptor.AuthenticationInterceptor;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.format.FormatterRegistry;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.validation.MessageCodesResolver;
import org.springframework.validation.Validator;
import org.springframework.web.method.support.HandlerMethodArgumentResolver;
import org.springframework.web.method.support.HandlerMethodReturnValueHandler;
import org.springframework.web.servlet.HandlerExceptionResolver;
import org.springframework.web.servlet.config.annotation.*;
import java.util.List;
/**
* @author :Mr.ZJW
* @date :Created 2022/2/28 10:25
* @description:新建Token拦截器
*/
@Configuration
public class InterceptorConfig implements WebMvcConfigurer {
@Override
public void addInterceptors(InterceptorRegistry registry) {
registry.addInterceptor(authenticationInterceptor())
.addPathPatterns("/**"); // 拦截所有请求,通过判断是否有 @LoginRequired 注解 决定是否需要登录
}
@Bean
public AuthenticationInterceptor authenticationInterceptor() {
return new AuthenticationInterceptor();
}
@Override
public void addArgumentResolvers(List<HandlerMethodArgumentResolver> arg0) {
// TODO Auto-generated method stub
}
@Override
public void addCorsMappings(CorsRegistry arg0) {
// TODO Auto-generated method stub
}
@Override
public void addFormatters(FormatterRegistry arg0) {
// TODO Auto-generated method stub
}
@Override
public void addResourceHandlers(ResourceHandlerRegistry arg0) {
// TODO Auto-generated method stub
}
@Override
public void addReturnValueHandlers(List<HandlerMethodReturnValueHandler> arg0) {
// TODO Auto-generated method stub
}
@Override
public void addViewControllers(ViewControllerRegistry arg0) {
// TODO Auto-generated method stub
}
@Override
public void configureAsyncSupport(AsyncSupportConfigurer arg0) {
// TODO Auto-generated method stub
}
@Override
public void configureContentNegotiation(ContentNegotiationConfigurer arg0) {
// TODO Auto-generated method stub
}
@Override
public void configureDefaultServletHandling(DefaultServletHandlerConfigurer arg0) {
// TODO Auto-generated method stub
}
@Override
public void configureHandlerExceptionResolvers(List<HandlerExceptionResolver> arg0) {
// TODO Auto-generated method stub
}
@Override
public void configureMessageConverters(List<HttpMessageConverter<?>> arg0) {
// TODO Auto-generated method stub
}
@Override
public void configurePathMatch(PathMatchConfigurer arg0) {
// TODO Auto-generated method stub
}
@Override
public void configureViewResolvers(ViewResolverRegistry arg0) {
// TODO Auto-generated method stub
}
@Override
public void extendHandlerExceptionResolvers(List<HandlerExceptionResolver> arg0) {
// TODO Auto-generated method stub
}
@Override
public void extendMessageConverters(List<HttpMessageConverter<?>> arg0) {
// TODO Auto-generated method stub
}
@Override
public MessageCodesResolver getMessageCodesResolver() {
// TODO Auto-generated method stub
return null;
}
@Override
public Validator getValidator() {
// TODO Auto-generated method stub
return null;
}
}
4、Interceptor包
AuthenticationInterceptor:
package com.geesun.Interceptor;
import com.auth0.jwt.JWT;
import com.auth0.jwt.JWTVerifier;
import com.auth0.jwt.algorithms.Algorithm;
import com.auth0.jwt.exceptions.JWTDecodeException;
import com.auth0.jwt.exceptions.JWTVerificationException;
import com.geesun.annotation.PassToken;
import com.geesun.annotation.UserLoginToken;
import com.geesun.pojo.User;
import com.geesun.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.lang.reflect.Method;
/**
* @author :Mr.ZJW
* @date :Created 2022/2/28 10:24
* @description:拦截器
*/
public class AuthenticationInterceptor implements HandlerInterceptor {
@Autowired
UserService userService;
@Override
public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object object) throws Exception {
String token = httpServletRequest.getHeader("token");// 从 http 请求头中取出 token
// 如果不是映射到方法直接通过
if(!(object instanceof HandlerMethod)){
return true;
}
HandlerMethod handlerMethod=(HandlerMethod)object;
Method method=handlerMethod.getMethod();
//检查是否有passtoken注释,有则跳过认证
if (method.isAnnotationPresent(PassToken.class)) {
PassToken passToken = method.getAnnotation(PassToken.class);
if (passToken.required()) {
return true;
}
}
//检查有没有需要用户权限的注解
if (method.isAnnotationPresent(UserLoginToken.class)) {
UserLoginToken userLoginToken = method.getAnnotation(UserLoginToken.class);
if (userLoginToken.required()) {
// 执行认证
if (token == null) {
throw new RuntimeException("无token,请重新登录");
}
// 获取 token 中的 user id
String userId;
try {
userId = JWT.decode(token).getAudience().get(0);
} catch (JWTDecodeException j) {
throw new RuntimeException("401");
}
User user = userService.findUserById(userId);
if (user == null) {
throw new RuntimeException("用户不存在,请重新登录");
}
// 验证 token
JWTVerifier jwtVerifier = JWT.require(Algorithm.HMAC256(user.getPassword())).build();
try {
jwtVerifier.verify(token);
} catch (JWTVerificationException e) {
throw new RuntimeException("401");
}
return true;
}
}
return true;
}
@Override
public void postHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, ModelAndView modelAndView) throws Exception {
}
@Override
public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) throws Exception {
}
}
5、utils包
TokenUtil:
package com.geesun.utils;
import com.auth0.jwt.JWT;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import javax.servlet.http.HttpServletRequest;
/**
* @author :Mr.ZJW
* @date :Created 2022/2/28 10:24
* @description:
*/
public class TokenUtil {
public static String getTokenUserId() {
String token = getRequest().getHeader("token");// 从 http 请求头中取出 token
String userId = JWT.decode(token).getAudience().get(0);
return userId;
}
/**
* 获取request
* @return
*/
public static HttpServletRequest getRequest() {
ServletRequestAttributes requestAttributes = (ServletRequestAttributes) RequestContextHolder
.getRequestAttributes();
return requestAttributes == null ? null : requestAttributes.getRequest();
}
}
6、pojo包
User:
package com.geesun.pojo;
import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableField;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import java.io.Serializable;
@Data
@AllArgsConstructor
@NoArgsConstructor
@TableName(value = "`user`")
public class User implements Serializable {
@TableId(value = "id", type = IdType.NONE)
private String id;
@TableField(value = "username")
private String username;
@TableField(value = "password")
private String password;
private static final long serialVersionUID = 1L;
}
7、controller包
UserController:
package com.geesun.controller;
import cn.hutool.json.JSONObject;
import com.geesun.annotation.UserLoginToken;
import com.geesun.common.CodeMsg;
import com.geesun.common.Result;
import com.geesun.pojo.User;
import com.geesun.service.UserService;
import com.geesun.service.impl.TokenService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletResponse;
/**
* @author :Mr.ZJW
* @date :Created 2022/2/26 10:47
* @description:
*/
@RestController
@RequestMapping("/user")
public class UserController {
@Autowired
private UserService userService;
@Autowired
private TokenService tokenService;
/**
* 查询用户信息
* @return
*/
@UserLoginToken
@GetMapping("/list")
public Result<Object> list(){
return Result.success(userService.list());
}
/**
* 登录验证
* @param user
* @param response
* @return
*/
@RequestMapping(value = "/login" ,method = RequestMethod.GET)
public Result<Object> login(User user, HttpServletResponse response) {
JSONObject jsonObject = new JSONObject();
//获取用户账号密码
User userForBase = new User();
userForBase.setId(userService.findByUsername(user).getId());
userForBase.setUsername(userService.findByUsername(user).getUsername());
userForBase.setPassword(userService.findByUsername(user).getPassword());
//判断账号或密码是否正确
if (!userForBase.getPassword().equals(user.getPassword())) {
return Result.error(CodeMsg.USER_OR_PASS_ERROR);
} else {
String token = tokenService.getToken(userForBase);
jsonObject.put("token", token);
Cookie cookie = new Cookie("token", token);
cookie.setPath("/");
response.addCookie(cookie);
return Result.success(jsonObject);
}
}
}
8、service包
UserService接口:
package com.geesun.service;
import com.baomidou.mybatisplus.extension.service.IService;
import com.geesun.pojo.User;
public interface UserService extends IService<User> {
int deleteByIds(Long[] ids);
int addUser(User user);
User findByUsername(User user);
User findUserById(String userId);
}
UserServiceImpl实现类:
package com.geesun.service.impl;
import cn.hutool.core.util.ArrayUtil;
import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.geesun.mapper.UserMapper;
import com.geesun.pojo.User;
import com.geesun.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.Arrays;
@Service
public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements UserService {
@Autowired
private UserMapper userMapper;
/**
* 判断用户名
* @param user
* @return
*/
public User findByUsername(User user){
return userMapper.selectOne(new LambdaQueryWrapper<User>().eq(User::getUsername,user.getUsername()));
}
public User findUserById(String userId) {
return userMapper.selectById(userId);
}
}
TokenService:
package com.geesun.service.impl;
import com.auth0.jwt.JWT;
import com.auth0.jwt.algorithms.Algorithm;
import com.geesun.pojo.User;
import org.springframework.stereotype.Service;
import java.util.Date;
/**
* @author :Mr.ZJW
* @date :Created 2022/2/28 10:20
* @description:
*/
@Service
public class TokenService {
public String getToken(User user) {
Date start = new Date();
long currentTime = System.currentTimeMillis() + 60* 60 * 1000;//一小时有效时间
Date end = new Date(currentTime);
String token = "";
token = JWT.create().withAudience(user.getId()).withIssuedAt(start).withExpiresAt(end)
.sign(Algorithm.HMAC256(user.getPassword()));
return token;
}
}
9、mapper包
package com.geesun.mapper;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.geesun.pojo.User;
public interface UserMapper extends BaseMapper<User> {
}
三、测试结果
1、登录验证
2、查询用户信息
这个方法加上了@UserLoginToken,所以要token才能查询
3、不加上Token进行测试就会出错提示
出错提示: