SpringBoot使用自定义注解+AOP+Redis实现接口限流的实例代码

    org.springframework.boot
    spring-boot-starter-aop



    org.springframework.boot
    spring-boot-starter-data-redis
       

@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface RateLimiter
{
    /**
     * 限流key
     */
     String key() default Constants.RATE_LIMIT_KEY;

    /**
     * 限流时间,单位秒
     */
     int time() default 60;

    /**
     * 限流次数
     */
    int count() default 100;

    /**
     * 限流类型
     */
    LimitType limitType() default LimitType.DEFAULT;

    /**
     * 限流后返回的文字
     */
    String limitMsg() default "访问过于频繁，请稍候再试";
}

@Aspect
@Component
public class RateLimiterAspect {

    private final static Logger log = LoggerFactory.getLogger(RateLimiterAspect.class);

    @Autowired
    private RedisUtils redisUtils;

    @Before("@annotation(rateLimiter)")
    public void doBefore(JoinPoint point, RateLimiter rateLimiter) throws Throwable
    {
        int time = rateLimiter.time();
        int count = rateLimiter.count();
        long total = 1L;

        String combineKey = getCombineKey(rateLimiter, point);
        try
        {
            if(redisUtils.hasKey(combineKey)){
                total = redisUtils.incr(combineKey,1);  //请求进来，对应的key加1
                if(total > count)
                    throw new ServiceRuntimeException(rateLimiter.limitMsg());
            }else{
                redisUtils.set(combineKey,1,time);  //初始化key
            }
        }
        catch (ServiceRuntimeException e)
        {
            throw e;
        }
        catch (Exception e)
        {
            throw new ServiceRuntimeException("网络繁忙，请稍候再试");
        }
    }

    /**
     * 获取限流key
     * @param rateLimiter
     * @param point
     * @return
     */
    public String getCombineKey(RateLimiter rateLimiter, JoinPoint point)
    {
        StringBuffer stringBuffer = new StringBuffer(rateLimiter.key());
        if (rateLimiter.limitType() == LimitType.IP)
        {
            stringBuffer.append(IpUtils.getIpAddr(ServletUtils.getRequest())).append("-");
        }
        MethodSignature signature = (MethodSignature) point.getSignature();
        Method method = signature.getMethod();
        Class targetClass = method.getDeclaringClass();
        stringBuffer.append(targetClass.getName()).append("-").append(method.getName());
        return stringBuffer.toString();
    }
}

@RestController
public class TestController {

    @RateLimiter(time = 60, count = 1, limitType = LimitType.IP, limitMsg = "一分钟内只能请求一次，请稍后重试")
    @GetMapping("/hello")
    public ResultMsg hello() {
        return ResultMsg.success("Hello World!");
    }
}

@RestControllerAdvice
public class GlobalExceptionHandler {
    private static final Logger log = LoggerFactory.getLogger(GlobalExceptionHandler.class);

    /**
     * 业务异常
     */
    @ExceptionHandler(ServiceRuntimeException.class)
    public ResultMsg handleServiceException(ServiceRuntimeException e, HttpServletRequest request)
    {
        return ResultMsg.error(e.getMessage());
    }

    /**
     * 系统异常
     */
    @ExceptionHandler(Exception.class)
    public ResultMsg handleException(Exception e, HttpServletRequest request)
    {
        return ResultMsg.error("系统异常");
    }
}