redis 实现登陆次数限制的思路详解

title: redis-login-limitation 

利用 redis 实现登陆次数限制, 注解 + aop, 核心代码很简单.

基本思路

比如希望达到的要求是这样: 在 1min 内登陆异常次数达到5次, 锁定该用户 1h

那么登陆请求的参数中, 会有一个参数唯一标识一个 user, 比如 邮箱/手机号/userName

用这个参数作为key存入redis, 对应的value为登陆错误的次数, string 类型, 并设置过期时间为 1min. 当获取到的 value == "4" , 说明当前请求为第 5 次登陆异常, 锁定.

所谓的锁定, 就是将对应的value设置为某个标识符, 比如"lock", 并设置过期时间为 1h

核心代码

定义一个注解, 用来标识需要登陆次数校验的方法

package io.github.xiaoyureed.redispractice.anno;
import java.lang.annotation.*;
@documented
@Target({ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
public @interface RedisLimit {
  
  String identifier();
  
  long watch();
  
  long lock();
  
  int times();
}

编写切面, 在目标方法前后进行校验, 处理...

package io.github.xiaoyureed.redispractice.aop;
@Component
@Aspect
// Ensure that current advice is outer compared with ControllerAOP
// so we can handling login limitation Exception in this aop advice.
//@Order(9)
@Slf4j
public class RedisLimitAOP {
  @Autowired
  private StringRedisTemplate stringRedisTemplate;
  @Around("@annotation(io.github.xiaoyureed.redispractice.anno.RedisLimit)")
  public Object handleLimit(ProceedingJoinPoint joinPoint) {
    MethodSignature methodSignature = (MethodSignature) joinPoint.getSignature();
    final Method   method     = methodSignature.getMethod();
    final RedisLimit redisLimitAnno = method.getAnnotation(RedisLimit.class);// 貌似可以直接在方法参数中注入 todo
    final String identifier = redisLimitAnno.identifier();
    final long  watch   = redisLimitAnno.watch();
    final int  times   = redisLimitAnno.times();
    final long  lock    = redisLimitAnno.lock();
    // final ServletRequestAttributes att= (ServletRequestAttributes) RequestContextHolder.currentRequestAttributes();
    // final HttpServletRequest    request     = att.getRequest();
    // final String   identifierValue = request.getParameter(identifier);
    String identifierValue = null;
    try {
      final Object arg      = joinPoint.getArgs()[0];
      final Field declaredField = arg.getClass().getDeclaredField(identifier);
      declaredField.setAccessible(true);
      identifierValue = (String) declaredField.get(arg);
    } catch (NoSuchFieldException e) {
      log.error(">>> invalid identifier [{}], cannot find this field in request params", identifier);
    } catch (IllegalAccessException e) {
      e.printStackTrace();
    }
    if (StringUtils.isBlank(identifierValue)) {
      log.error(">>> the value of RedisLimit.identifier cannot be blank, invalid identifier: {}", identifier);
    }
    // check User locked
    final ValueOperations ssOps = stringRedisTemplate.opsForValue();
    final String      flag = ssOps.get(identifierValue);
    if (flag != null && "lock".contentEquals(flag)) {
      final baseResp result = new baseResp();
      result.setErrMsg("user locked");
      result.setCode("1");
      return new ResponseEntity<>(result, HttpStatus.OK);
    }
    ResponseEntity result;
    try {
      result = (ResponseEntity) joinPoint.proceed();
    } catch (Throwable e) {
      result = handleLoginException(e, identifierValue, watch, times, lock);
    }
    return result;
  }
  private ResponseEntity handleLoginException(Throwable e, String identifierValue, long watch, int times, long lock) {
    final baseResp result = new baseResp();
    result.setCode("1");
    if (e instanceof LoginException) {
      log.info(">>> handle login exception...");
      final ValueOperations ssOps = stringRedisTemplate.opsForValue();
      Boolean  exist = stringRedisTemplate.hasKey(identifierValue);
      // key doesn't exist, so it is the first login failure
      if (exist == null || !exist) {
 ssOps.set(identifierValue, "1", watch, TimeUnit.SECONDS);
 result.setErrMsg(e.getMessage());
 return new ResponseEntity<>(result, HttpStatus.OK);
      }
      String count = ssOps.get(identifierValue);
      // has been reached the limitation
      if (Integer.parseInt(count) + 1 == times) {
 log.info(">>> [{}] has been reached the limitation and will be locked for {}s", identifierValue, lock);
 ssOps.set(identifierValue, "lock", lock, TimeUnit.SECONDS);
 result.setErrMsg("user locked");
 return new ResponseEntity<>(result, HttpStatus.OK);
      }
      ssOps.increment(identifierValue);
      result.setErrMsg(e.getMessage() + "; you have try " + ssOps.get(identifierValue) + "times.");
    }
    log.error(">>> RedisLimitAOP cannot handle {}", e.getClass().getName());
    return new ResponseEntity<>(result, HttpStatus.OK);
  }
}

这样使用:

package io.github.xiaoyureed.redispractice.web;
@RestController
public class SessionResources {
  @Autowired
  private SessionService sessionService;
  
  @RedisLimit(identifier = "name", watch = 30, times = 5, lock = 10)
  @RequestMapping(value = "/session", method = RequestMethod.POST)
  public ResponseEntity login(@Validated @RequestBody LoginReq req) {
    return new ResponseEntity<>(sessionService.login(req), HttpStatus.OK);
  }
}

references

https://github.com/xiaoyureed/redis-login-limitation

总结

以上所述是小编给大家介绍的redis 实现登陆次数限制的思路详解,希望对大家有所帮助，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对考高分网网站的支持！
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