jwt后端鉴权

1.将用户信息存储到localStorage里
localStorage.setItem("user",JSON.stringify(res.data));

2.路由守卫
//路由守卫
router.beforeEach((to,from,next)=> {
if(to.path === '/login'){
next();
}
const user = localStorage.getItem("user");
if(!user && to.path !=='/login'){
return next("/login")
}
next();
})

3.jwt在后端鉴权
import org.springframework.context.annotation.Configuration;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.servlet.config.annotation.PathMatchConfigurer;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

@Configuration
public class WebConfig implements WebMvcConfigurer {
@Override
public void configurePathMatch(PathMatchConfigurer configurer){
//指定controller统一接口
configurer.addPathPrefix("/api",clazz ->clazz.isAnnotationPresent(RestController.class));
}
}

前端代码
const user = localStorage.getItem("user");
if(user){
config.headers['token'] = JSON.parse(user).token;
}

拦截器
package com.example.common;

import cn.hutool.core.util.StrUtil;
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.entity.Admin;
import com.example.exception.CustomException;
import com.example.service.AdminService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**

• 拦截器A
  */
  @Component
  public class JwtInterceptor implements HandlerInterceptor {
  private static final Logger log = LoggerFactory.getLogger(JwtInterceptor.class);

  @Resource
  private AdminService adminService;

  @Override
  public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler){

   // 让OPTIONS请求通过
   if (request.getMethod().equals("OPTIONS")) {
       response.setStatus(HttpServletResponse.SC_OK);
       return true;
   }
  
   // 获取token
   String token = request.getHeader("token");
   if (StrUtil.isBlank(token)){
       token = request.getParameter("token");
   }
  
   // 开始执行认证
   if (StrUtil.isBlank(token)){
       throw new CustomException("无token，请重新登录");
   }
   // 获取 token 中的adminId
   String adminId;
   Admin admin;
   try {
       adminId = JWT.decode(token).getAudience().get(0);
       // 根据token中的userid查询数据库
       admin = adminService.findById(Integer.parseInt(adminId));
   }catch (Exception e){
       String errMsg = "token验证失败，请重新登录";
       log.error(errMsg+",token = " + token,e);
       throw new CustomException(errMsg);
   }
   if (admin == null){
       throw new CustomException("用户不存在，请重新登录");
   }
   try {
       JWTVerifier jwtVerifier = JWT.require(Algorithm.HMAC256(admin.getPassword())).build();
       // 根据token中的userid查询数据库
      jwtVerifier.verify(token);
   }catch (JWTVerificationException e){
       throw new CustomException("token验证失败，请重新登录");
   }
   log.info("token验证成功，允许放行");
   return true;
  

  }
  }