SpringBoot+SpringSession+Redis实现session共享及唯一登录

转载：https://blog.csdn.net/xjj1040249553/article/details/82658889

一、pom.xml配置 

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>
 
<dependency>
    <groupId>org.springframework.session</groupId>
    <artifactId>spring-session-data-redis</artifactId>
</dependency>

二、application.properties的redis配置

#redis
spring.redis.host=127.0.0.1
spring.redis.port=6379
spring.redis.password=123456
spring.redis.pool.max-idle=8
spring.redis.pool.min-idle=0
spring.redis.pool.max-active=8
spring.redis.pool.max-wait=-1
#超时一定要大于0
spring.redis.timeout=3000
spring.session.store-type=redis

在配置redis时需要确保redis安装正确，并且配置notify-keyspace-events Egx，spring.redis.timeout设置为大于0，我当时这里配置为0时springboot时启不起来。

三、编写登录状态拦截器RedisSessionInterceptor

//拦截登录失效的请求
public class RedisSessionInterceptor implements HandlerInterceptor
{
    @Autowired
    private StringRedisTemplate redisTemplate;
 
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception
    {
        //无论访问的地址是不是正确的，都进行登录验证，登录成功后的访问再进行分发，404的访问自然会进入到错误控制器中
        HttpSession session = request.getSession();
        if (session.getAttribute("loginUserId") != null)
        {
            try
            {
                //验证当前请求的session是否是已登录的session
                String loginSessionId = redisTemplate.opsForValue().get("loginUser:" + (long) session.getAttribute("loginUserId"));
                if (loginSessionId != null && loginSessionId.equals(session.getId()))
                {
                    return true;
                }
            }
            catch (Exception e)
            {
                e.printStackTrace();
            }
        }
 
        response401(response);
        return false;
    }
 
    private void response401(HttpServletResponse response)
    {
        response.setCharacterEncoding("UTF-8");
        response.setContentType("application/json; charset=utf-8");
 
        try
        {
            response.getWriter().print(JSON.toJSONString(new ReturnData(StatusCode.NEED_LOGIN, "", "用户未登录！")));
        }
        catch (IOException e)
        {
            e.printStackTrace();
        }
    }
 
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception
    {
 
    }
 
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception
    {
 
    }
}

四、配置拦截器

@Configuration
public class WebSecurityConfig extends WebMvcConfigurerAdapter
{
    @Bean
    public RedisSessionInterceptor getSessionInterceptor()
    {
        return new RedisSessionInterceptor();
    }
 
    @Override
    public void addInterceptors(InterceptorRegistry registry)
    {
        //所有已api开头的访问都要进入RedisSessionInterceptor拦截器进行登录验证，并排除login接口(全路径)。必须写成链式，分别设置的话会创建多个拦截器。
        //必须写成getSessionInterceptor()，否则SessionInterceptor中的@Autowired会无效
        registry.addInterceptor(getSessionInterceptor()).addPathPatterns("/api/**").excludePathPatterns("/api/user/login");
        super.addInterceptors(registry);
    }
}

五、登录控制器

@RestController
@RequestMapping(value = "/api/user")
public class LoginController
{
    @Autowired
    private UserService userService;
 
    @Autowired
    private StringRedisTemplate redisTemplate;
 
    @RequestMapping("/login")
    public ReturnData login(HttpServletRequest request, String account, String password)
    {
        User user = userService.findUserByAccountAndPassword(account, password);
        if (user != null)
        {
            HttpSession session = request.getSession();
            session.setAttribute("loginUserId", user.getUserId());
            redisTemplate.opsForValue().set("loginUser:" + user.getUserId(), session.getId());
 
            return new ReturnData(StatusCode.REQUEST_SUCCESS, user, "登录成功！");
        }
        else
        {
            throw new MyException(StatusCode.ACCOUNT_OR_PASSWORD_ERROR, "账户名或密码错误！");
        }
    }
 
    @RequestMapping(value = "/getUserInfo")
    public ReturnData get(long userId)
    {
        User user = userService.findUserByUserId(userId);
        if (user != null)
        {
            return new ReturnData(StatusCode.REQUEST_SUCCESS, user, "查询成功！");
        }
        else
        {
            throw new MyException(StatusCode.USER_NOT_EXIST, "用户不存在！");
        }
    }
}

六、效果

我在浏览器上登录，然后获取用户信息，再在postman上登录相同的账号，浏览器再获取用户信息，就会提示401错误了，浏览器需要重新登录才能获取得到用户信息，同样，postman上登录的账号就失效了。

浏览器：

postman：

七、核心原理详解

分布式session需要解决两个难点：1、正确配置redis让springboot把session托管到redis服务器。2、唯一登录。

1、redis：

redis需要能正确启动到出现如下效果才证明redis正常配置并启动

同时还要保证配置正确

@EnableCaching
@EnableRedisHttpSession(maxInactiveIntervalInSeconds = 30)//session过期时间(秒)
@Configuration
public class RedisSessionConfig
{
    @Bean
    public static ConfigureRedisAction configureRedisAction()
    {
        //让springSession不再执行config命令
        return ConfigureRedisAction.NO_OP;
    }
}

springboot启动后能在redis上查到缓存的session才能说明整个redis+springboot配置成功！

2、唯一登录：

1、用户登录时，在redis中记录该userId对应的sessionId，并将userId保存到session中。

HttpSession session = request.getSession();
session.setAttribute("loginUserId", user.getUserId());
redisTemplate.opsForValue().set("loginUser:" + user.getUserId(), session.getId());

2、访问接口时，会在RedisSessionInterceptor拦截器中的preHandle()中捕获，然后根据该请求发起者的session中保存的userId去redis查当前已登录的sessionId，若查到的sessionId与访问者的sessionId相等，那么说明请求合法，放行。否则抛出401异常给全局异常捕获器去返回给客户端401状态。

唯一登录经过我的验证后满足需求，暂时没有出现问题，也希望大家能看看有没有问题，有的话给我点好的建议！