后端Jwt实现Token编码、解码以及axios的request请求头的Token传输方式

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目录

一、什么是JWT：

二、Jwt的使用：

第一步：引入依赖：

第二步：配置拦截器：JwtInterceptor.java：

其中异常文件ServiceException配置如下：

全局异常文件GlobalException.java文件配置如下：

其中所需的Result配置如下：

第三步：配置拦截设置文件：InterceptorConfig.java：

第四步：配置Token工具类文件：TokenUtils.java：

request.js的axios封装文件为：

文件布局大致如下：

一、什么是JWT：

        JWT是token的一种实现方式，全称是：JSON Wwb Token。简单来讲，Jwt是一种字符串，可以根据用户信息进行相关的编码操作生成带有用户信息的JWT token，我们可以根据这个来判断其信息是否正确或者是否被篡改。

二、Jwt的使用：

首先是后端：

第一步：引入依赖：

 <dependency> <groupId>com.auth0</groupId> <artifactId>java-jwt</artifactId> <version>4.3.0</version> </dependency>

第二步：配置拦截器：JwtInterceptor.java：

import com.auth0.jwt.JWT; import com.auth0.jwt.JWTVerifier; import com.auth0.jwt.algorithms.Algorithm; import com.auth0.jwt.exceptions.JWTVerificationException; import com.example.cqcrhouduan.Utils.TokenUtils; import com.example.cqcrhouduan.exception.ServiceException; import com.example.cqcrhouduan.mapper.UserMapper; import io.micrometer.common.util.StringUtils; import jakarta.servlet.http.HttpServletRequest; import jakarta.servlet.http.HttpServletResponse; import lombok.extern.slf4j.Slf4j; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Component; import org.springframework.web.servlet.HandlerInterceptor; @Component @Slf4j public class JwtInterceptor implements HandlerInterceptor { @Autowired private UserMapper userMapper; @Override public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) { if(request.getMethod().equals("OPTIONS")) { return true; } String token = request.getHeader("token"); if (StringUtils.isEmpty(token)) { token = request.getParameter("token"); } token = token; // 执行认证 if (StringUtils.isEmpty(token)) { throw new ServiceException(401, "无token，请重新登录"); } // 获取 token 中的adminId String userId; User user; try { userId = JWT.decode(token).getAudience().get(0); //解码 // 根据token中的userid查询数据库 user = userMapper.getById(Integer.parseInt(userId)); user = user; } catch (Exception e) { String errMsg = "token验证失败，请重新登录"; log.error(errMsg + ", token=" + token, e); throw new ServiceException(401, errMsg); } if (user == null) { throw new ServiceException(401, "用户不存在，请重新登录"); } try { // 用户密码加签验证 token JWTVerifier jwtVerifier = JWT.require(Algorithm.HMAC256(user.getPassword())).build(); jwtVerifier.verify(token); // 验证token } catch (JWTVerificationException e) { throw new ServiceException(401, "token验证失败，请重新登录"); } return true; } }

其中异常文件ServiceException配置如下：

import com.example.cqcrhouduan.pojo.Result; import lombok.Data; @Data public class ServiceException extends RuntimeException { private int code; public ServiceException(String msg){ super(msg); this.code = 500; } public ServiceException(int code, String msg){ super(msg); this.code = code; } } 

全局异常文件GlobalException.java文件配置如下：

import com.example.cqcrhouduan.pojo.Result; import org.springframework.web.bind.annotation.ControllerAdvice; import org.springframework.web.bind.annotation.ExceptionHandler; import org.springframework.web.bind.annotation.ResponseBody; //自定义异常 @ControllerAdvice public class GlobalException { @ExceptionHandler(ServiceException.class) @ResponseBody public Result serviceException(ServiceException e){ return Result.error(e.getCode(),e.getMessage()); } } 

其中所需的Result配置如下：

import lombok.AllArgsConstructor; import lombok.Data; import lombok.NoArgsConstructor; @Data @NoArgsConstructor @AllArgsConstructor public class Result { private Integer code; private String msg; private Object data; public static Result success(Object data){ return new Result(200,"success",data); } public static Result success(){ return new Result(200,"success",null); } public static Result error(String msg){ return new Result(500,msg,null); } public static Result error(Integer Code ,String msg){ return new Result(Code,msg,null); } } 

第三步：配置拦截设置文件：InterceptorConfig.java：

import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import org.springframework.web.servlet.config.annotation.InterceptorRegistry; import org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport; @Configuration public class InterceptorConfig extends WebMvcConfigurationSupport { // 加自定义拦截器JwtInterceptor，设置拦截规则 @Override protected void addInterceptors(InterceptorRegistry registry) { registry.addInterceptor(jwtInterceptor()) .addPathPatterns("/") .excludePathPatterns("/login","/register"); super.addInterceptors(registry); } @Bean public JwtInterceptor jwtInterceptor(){ return new JwtInterceptor(); } } 

第四步：配置Token工具类文件：TokenUtils.java：

import com.auth0.jwt.JWT; import com.auth0.jwt.algorithms.Algorithm; import com.example.cqcrhouduan.mapper.UserMapper; import com.example.cqcrhouduan.pojo.User; import jakarta.annotation.PostConstruct; import jakarta.annotation.Resource; import jakarta.servlet.http.HttpServletRequest; import lombok.extern.slf4j.Slf4j; import org.apache.commons.lang3.StringUtils; import org.springframework.stereotype.Component; import org.springframework.web.context.request.RequestContextHolder; import org.springframework.web.context.request.ServletRequestAttributes; @Component @Slf4j public class TokenUtils { private static UserMapper staticAdminService; @Resource private UserMapper adminService; @PostConstruct public void setUserService() { staticAdminService = adminService; } / * 生成token * * @return */ public static String genToken(int adminId, String sign) { return JWT.create().withAudience(Integer.toString(adminId)) // 将 user id 保存到 token 里面,作为载荷 .withExpiresAt(DateUtil.offsetHours(new Date(), 2)) // 2小时后token过期 .sign(Algorithm.HMAC256(sign)); // 以 password 作为 token 的密钥 } / * 获取当前登录的用户信息 * * @return user对象 * /admin?token=xxxx */ public static User getCurrentAdmin() { String token = null; try { HttpServletRequest request = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getRequest(); token = request.getHeader("token"); if (StringUtils.isNotBlank(token)) { token = request.getParameter("token"); } if (StringUtils.isBlank(token)) { log.error("获取当前登录的token失败， token: {}", token); return null; } String userId = JWT.decode(token).getAudience().get(0); return staticAdminService.getById(Integer.valueOf(userId)); } catch (Exception e) { log.error("获取当前登录的管理员信息失败, token={}", token, e); return null; } } } 

然后是前端axios配置： 

request.js的axios封装文件为：

import axios from "axios"; import router from "../modules/router.js"; const request = axios.create({ baseURL:'http://localhost:8080/', //自己的请求地址 timeout:30000, }) // Add a request interceptor request.interceptors.request.use((config) => { config.headers['Content-Type'] = 'application/json;charset=utf-8'; let user = JSON.parse(localStorage.getItem("userToken") || '{}') // console.log(user.token) //查看token config.headers['token'] = user.token // config.headers.Authorization = localStorage.getItem("userToken") console.log("ok") // Do something before request is sent return config; }, error => { console.log('request error' + error) // Do something with request error return Promise.reject(error); }); // Add a response interceptor request.interceptors.response.use(response => { let res = response.data; if (typeof res === 'string'){ res = res ? JSON.parse(res) : res } // if(res.code === 401){ //自动跳转 // router.push('/') // } // Any status code that lie within the range of 2xx cause this function to trigger // Do something with response data return res; }, function (error) { // Any status codes that falls outside the range of 2xx cause this function to trigger // Do something with response error console.log('response error' + error) return Promise.reject(error); }); export default request 

文件布局大致如下：