SpringBoot登录功能和登录拦截

一：登录功能

1.前端输入用户名和密码校验通过之后发送异步请求，并传递参数

handleSubmit2(ev) {
    this.$refs.ruleForm2.validate((valid) => {
      if (valid) {
        this.logining = true; //显示加载框
        var loginParams = {
          userName: this.ruleForm2.account,
          password: this.ruleForm2.checkPass,
        };

        this.$http.post("/login",loginParams).then(res=>{
          if(res.data.success){//登录成功
            //跳转到后台首页
            this.$router.push({ path: '/echarts' });
            //关闭加载框
            this.logining = false;
          }else{//登录失败
            this.logining = false;
            this.$message.error(res.data.message);
          }
        }).catch(res=>{
          this.$message.warning("系统繁忙，请稍后重试!");
        })
      } else {
        this.$message.warning("表单验证未通过");
      }
    });
}

2.后端接收数据并编写登录业务

    a.SystemController
        //后端怎么接收多个数据：对象【自定义对象 + Map】
        @PostMapping("/login")
        public AjaxResult login(@RequestBody Map<String,String> map){
            try {
                SysUser sysUser = sysUserService.login(map);
                return new AjaxResult();
            } catch (BusinessException e) {
                return new AjaxResult(false,e.getMessage());
            } catch (Exception e) {
                e.printStackTrace();
                return new AjaxResult(false,"系统繁忙，请稍后重试!");
            }
        }
    b.登录业务
        @Override
        public SysUser login(Map<String, String> map) {
            String userName = map.get("userName");
            String password = map.get("password");

            //一：判空，前端虽然做了校验，后端也要校验，前端的代码不安全容易被禁用
            if(StrUtil.isEmptyIfStr(userName) || StrUtil.isEmptyIfStr(password)){
                throw new BusinessException("信息不能为空");
            }

//二：判断用户名
            SysUser sysUser = sysUserMapper.findByUserName(userName);
            if(sysUser == null){
                throw new BusinessException("用户名不存在");
            }
            //三：校验密码，要保证添加数据或注册的时候也要用SecureUtil.md5进行加密
            if(!sysUser.getPassword().equals(SecureUtil.md5(password))){
                throw new BusinessException("密码不正确");
            }
            return sysUser;
        }
    c.SysUserMapper.xml
        
        <select id="findByUserName" resultType="cn.itsource.domain.SysUser">
            select * from sys_user where user_name=#{userName}
        </select>

二：前端显示用户名

三：登录拦截

    登录拦截的目的：防止不登录就访问受限资源
    登录拦截的业务：判断session中是否有登录信息，有放行，如果没有跳转到登录页面
    登录拦截实现：
        1.登录成功将登录信息放在session中
            session.setAttribute("user_in_session",sysUser);
        2.写一个类实现HandlerInterceptor接口，实现一个preHandler方法
            @Component
            public class LoginInterceptor implements HandlerInterceptor {
                @Override
                public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
                    HttpSession session = request.getSession();
                    Object obj = session.getAttribute("user_in_session");
                    if(obj == null){//没有登录或登录过期了
                        //跳转到登录页面
                        System.out.println("跳转到登录页面");
                        //拦截
                        return false;
                    }
                    //放行
                    return true;
                }
            }
        3.配置
            @Configuration
            public class LoginConfig implements WebMvcConfigurer {
                @Autowired
                private LoginInterceptor loginInterceptor;
                @Override
                public void addInterceptors(InterceptorRegistry registry) {

                    registry.addInterceptor(loginInterceptor)
                            .addPathPatterns("/**")
                            //只要跟登录，注册，测试相关的都要排除调
                            .excludePathPatterns("/login");
                }
            }
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问题：前后端分离项目无法自动传递Cookie，需要配置
在main.js中配置：axios.defaults.withCredentials = true; //当前请求为跨域类型时，是否在请求中协带cookie