SpringBoot+JWT实现注册、登录、状态续签流程分析-编程学习网

一、实现流程

1.注册

2.登录

3.登录保持【状态续签】

二、实现方法

项目结构

1.引入依赖

<!-- spring-web -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- mysql连接器 -->
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
</dependency>
<!-- Mybatis Plus -->
<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>mybatis-plus-boot-starter</artifactId>
    <version>3.4.3.4</version>
</dependency>
<!-- druid -->
<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid-spring-boot-starter</artifactId>
    <version>1.2.8</version>
</dependency>
<!-- jwt -->
<dependency>
    <groupId>com.auth0</groupId>
    <artifactId>java-jwt</artifactId>
    <version>3.10.3</version>
</dependency>

2.application配置文件

spring:
  application:
    name: jwtLogin   # 应用名称
  datasource:
    druid:
      url: jdbc:mysql://192.168.0.111:3306/login_test?useSSL=false&serverTimezone=UTC
      username: samon
      password: 123456
      driver-class-name: com.mysql.jdbc.Driver
server:
  port: 8848   # 应用服务 WEB 访问端口

3.mysql建表

用户表

4.Bean

1.bean/user.java
用户bean

package com.cxstar.bean;
import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
import lombok.Data;
import java.util.Date;
@Data
public class User {
    // 自增长id
    @TableId(type = IdType.AUTO)
    private Integer id;
    private String userName;
    private String passWord;
    private Date createTime;
    private Date lastLogin;
    public  User() {}
    public User(Integer id, String userName) {
        this.id = id;
        this.userName = userName;
    }
}

2.bean/ServiceRes.java
统一Service返回类

package com.cxstar.bean;
import lombok.Data;
@Data
public class ServiceRes {
    private Integer code;
    private String msg;
    private String jwt;
    private ServiceRes() {}
    public ServiceRes(Integer code, String msg) {
        this.code = code;
        this.msg = msg;
    }
    public ServiceRes(Integer code, String msg, String jwt) {
        this.code = code;
        this.msg = msg;
        this.jwt = jwt;
    }
}

3.bean/ControllerRes.java
统一Controller返回类

package com.cxstar.bean;
import lombok.Data;
@Data
public class ControllerRes {
    private Integer code;
    private String msg;
    public ControllerRes(Integer code, String msg) {
        this.code = code;
        this.msg = msg;
    }
}

5.Mapper mapper/UserMapper.java
继承MP

package com.cxstar.mapper;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.cxstar.bean.User;
import org.apache.ibatis.annotations.Mapper;
@Mapper
public interface UserMapper extends BaseMapper<User> {
}

6.service service.userService.interface
登录、注册、改密业务【状态续签测试】

package com.cxstar.service;
import com.cxstar.bean.ServiceRes;
import com.cxstar.bean.User;
public interface userService {
    // 注册
    ServiceRes register(User user);
    // 登录
    ServiceRes login(User user);
    // 改密【带权限业务，用于状态续签测试】
    ServiceRes changePassWord(User user);
}

service.impl.UserServiceImpl.java
登录、注册、改密业务【状态续签测试】

package com.cxstar.service.impl;
import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.cxstar.bean.ServiceRes;
import com.cxstar.bean.User;
import com.cxstar.mapper.UserMapper;
import com.cxstar.service.userService;
import com.cxstar.utils.JwtUtil;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.util.DigestUtils;
import java.nio.charset.StandardCharsets;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
@Slf4j
@Service
public class UserServiceImpl implements userService {
    @Autowired
    UserMapper userMapper;
    
    @Override
    public ServiceRes register(User user) {
        // 判断用户名是否唯一
        if(this.checkUserNameIsUnique(user)) {
            // 判断用户名密码是否合法
            if(this.checkUserNameAndPassword(user)) {
                // 密码MD5加密
                user.setPassWord(this.MD5Code(user.getPassWord()));
                // 加入创建时间
                user.setCreateTime(new Date());
                // 入库
                userMapper.insert(user);
                return new ServiceRes(1, "注册成功");
            } else return new ServiceRes(-1, "用户名或密码不合法");
        } else return new ServiceRes(-1, "用户名已存在");
    }
    
    @Override
    public ServiceRes login(User user) {
        // 判断用户名密码是否合法
        if(this.checkUserNameAndPassword(user)) {
            // 密码MD5加密
            user.setPassWord(this.MD5Code(user.getPassWord()));
            // 检查用户是否存在
            User curUser = this.checkUserIsExit(user);
            if(curUser!=null) {
                // 更新用户最后登录时间
                curUser.setLastLogin(new Date());
                userMapper.updateById(curUser);
                // 生成jwt
                Map<String, String> payload = new HashMap<>();
                payload.put("userId", curUser.getId().toString()); // 加入一些非敏感的用户信息
                payload.put("userName", curUser.getUserName());    // 加入一些非敏感的用户信息
                String jwt = JwtUtil.generateToken(payload);
                return new ServiceRes(1, "登录成功", jwt);
            } else return new ServiceRes(-1, "用户名或密码错误");
        } else return new ServiceRes(-1, "用户名或密码不合法");
    }
    
    @Override
    public ServiceRes changePassWord(User user) {
        if(this.updatePassWord(user)) return new ServiceRes(1, "改密成功");
        else return new ServiceRes(-1, "改密失败");
    }
    
    private String MD5Code(String text) {
        return DigestUtils.md5DigestAsHex(text.getBytes(StandardCharsets.UTF_8));
    }
    
    private Boolean updatePassWord(User user) {
        // 密码非对称加密
        user.setPassWord(this.MD5Code(user.getPassWord()));
        // 更新密码
        return userMapper.updateById(user)>0;
    }
    
    private User checkUserIsExit(User user) {
        LambdaQueryWrapper<User> lqw = new LambdaQueryWrapper<>();
        lqw.eq(User::getUserName, user.getUserName());
        lqw.eq(User::getPassWord, user.getPassWord());
        return userMapper.selectOne(lqw);
    }
    
    private Boolean checkUserNameIsUnique(User user) {
        LambdaQueryWrapper<User> lqw = new LambdaQueryWrapper<>();
        lqw.eq(User::getUserName, user.getUserName());
        List<User> userList = userMapper.selectList(lqw);
        return userList.size() == 0;
    }
    
    private Boolean checkUserNameAndPassword(User user) {
        String regex = "^[_a-z0-9A-Z]+$";
        return user.getUserName().matches(regex) && user.getPassWord().matches(regex);
    }

}

6.Controller controller/UserController.java
登录、注册、改密业务【状态续签测试】

package com.cxstar.controller;
import com.cxstar.bean.ControllerRes;
import com.cxstar.bean.ServiceRes;
import com.cxstar.bean.User;
import com.cxstar.service.userService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.PutMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@Slf4j
@Controller
@ResponseBody
@RequestMapping("/user")
public class UserController {
    @Autowired
    userService userService;
    @PostMapping("/register")
    public ControllerRes register(User user) {
        // 注册
        ServiceRes serviceRes = userService.register(user);
        return new ControllerRes(serviceRes.getCode(), serviceRes.getMsg());
    }
    @PostMapping("/login")
    public ControllerRes login(User user, HttpServletResponse response) {
        // 登录
        ServiceRes serviceRes = userService.login(user);
        // 登录成功后往响应头插入jwt
        if(serviceRes.getJwt() != null) response.addHeader("access-token", serviceRes.getJwt());
        return new ControllerRes(serviceRes.getCode(), serviceRes.getMsg());
    }
    @PutMapping("/pwd")
    public ControllerRes changePassWord(User user, HttpServletRequest request) {
        // 取出jwt中的用户
        User jwtUser = (User)request.getAttribute("jwt-user");
        // 合并jwt中用户的用户名与传入用户的新密码
        // 此处不能直接使用传入的用户名，防止恶意修改其他用户的密码
        user.setId(jwtUser.getId());
        // 改密
        ServiceRes serviceRes = userService.changePassWord(user);
        return new ControllerRes(serviceRes.getCode(), serviceRes.getMsg());
    }
}

7.JWT工具类 utils/JwtUtil.java
生成和解析 token 的方法

package com.cxstar.utils;
import com.auth0.jwt.JWT;
import com.auth0.jwt.JWTCreator;
import com.auth0.jwt.algorithms.Algorithm;
import com.auth0.jwt.interfaces.DecodedJWT;
import com.auth0.jwt.interfaces.JWTVerifier;
import java.util.Calendar;
import java.util.Date;
import java.util.Map;
public class JwtUtil {
    // 签名密钥
    private static final String SECRET = "hello JWT *%$#$&";
    
    public static String generateToken(Map<String,String> payload){
        // 指定token过期时间
        Calendar calendar = Calendar.getInstance();
        calendar.add(Calendar.HOUR, 24);  // 24小时
        JWTCreator.Builder builder = JWT.create();
        // 构建payload
        payload.forEach(builder::withClaim);
        // 指定签发时间、过期时间 和 签名算法，并返回token
        String token = builder.withIssuedAt(new Date()).withExpiresAt(calendar.getTime()).sign(Algorithm.HMAC256(SECRET));
        return token;
    }

    
    public static DecodedJWT decodeToken(String token){
        JWTVerifier jwtVerifier = JWT.require(Algorithm.HMAC256(SECRET)).build();
        DecodedJWT decodedJWT = jwtVerifier.verify(token);
        return decodedJWT;
    }
}

8.HandlerInterceptor拦截器 interceptor.java
拦截器业务实现

package com.cxstar.interceptor;

import com.alibaba.fastjson.JSONObject;
import com.auth0.jwt.exceptions.JWTDecodeException;
import com.auth0.jwt.exceptions.TokenExpiredException;
import com.auth0.jwt.interfaces.DecodedJWT;
import com.cxstar.bean.ControllerRes;
import com.cxstar.bean.User;
import com.cxstar.utils.JwtUtil;
import lombok.extern.slf4j.Slf4j;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;


@Slf4j
public class PermisssionInterceptor implements HandlerInterceptor {

    // 目标方法执行前调用
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws IOException {

        // 检查用户JWT
        String jwt = request.getHeader("access-token");

        // 校验并取出私有信息
        try {

            // token 解码
            DecodedJWT dj = JwtUtil.decodeToken(jwt);

            // 取出基本用户信息加入请求头 --------------------------------------------------------------------------------
            String userId = dj.getClaim("userId").asString();
            String userName = dj.getClaim("userName").asString();
            // jwt校验合格的，将 jwt 中存的用户信息加入请求头，不合格的，请求头存个空用户
            request.setAttribute("jwt-user", userId!=null?new User(Integer.valueOf(userId), userName):new User());
            // -------------------------------------------------------------------------------------------------------

            // 计算当前时间是否超过过期时间的一半，如果是就帮用户续签 --------------------------
            // 此处并不是永久续签，只是为 大于过期时间的一半 且 小于过期时间 的 token 续签
            Long expTime = dj.getExpiresAt().getTime();
            Long iatTime = dj.getIssuedAt().getTime();
            Long nowTime = new Date().getTime();
            if((nowTime-iatTime) > (expTime-iatTime)/2) {
                // 生成新的jwt
                Map<String, String> payload = new HashMap<>();
                payload.put("userId", userId); // 加入一些非敏感的用户信息
                payload.put("userName", userName);    // 加入一些非敏感的用户信息
                String newJwt = JwtUtil.generateToken(payload);
                // 加入返回头
                response.addHeader("access-token", newJwt);
            }
            // -----------------------------------------------------------------------

            return true;

        } catch (JWTDecodeException e) {
            log.error("令牌错误");
            addResBody(response, new ControllerRes(-1, "令牌错误"));  // 新增返回体
            return false;

        } catch (TokenExpiredException e) {
            log.error("令牌过期");
            addResBody(response, new ControllerRes(-1, "令牌过期"));  // 新增返回体
            return false;
        }

    }

    // 目标方法执行后调用
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        HandlerInterceptor.super.postHandle(request, response, handler, modelAndView);
    }

    // 页面渲染前调用
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        HandlerInterceptor.super.afterCompletion(request, response, handler, ex);
    }

    private void addResBody(HttpServletResponse response, ControllerRes res) throws IOException {

        response.setStatus(HttpServletResponse.SC_FORBIDDEN);        // 设置状态码

        response.setCharacterEncoding("UTF-8");
        response.setContentType("application/json; charset=utf-8");
        PrintWriter out = response.getWriter();
        out.write(JSONObject.toJSONString(res));
        out.flush();
        out.close();

    }

}

config/PermissionWebConfig.java
拦截器拦截规则

package com.cxstar.config;
import com.cxstar.interceptor.PermisssionInterceptor;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
@Configuration
public class PermissionWebConfig implements WebMvcConfigurer {
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(new PermisssionInterceptor())
                .addPathPatterns("/**")    // 拦截哪些页面
                .excludePathPatterns("/user/login", "/user/register");   // 放行哪些页面
    }
}