SpringBoot在一定时间内限制接口请求次数的实现示例_java

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


net.jodah
expiringmap
0.5.8

@Documented
@Target(ElementType.METHOD) // 说明该注解只能放在方法上面
@Retention(RetentionPolicy.RUNTIME)
public @interface LimitRequest {
long time() default 6000; // 限制时间 单位：毫秒
int count() default 1; // 允许请求的次数
}

@Aspect
@Component
public class LimitRequestAspect {
private static ConcurrentHashMap> book = new ConcurrentHashMap<>();
// 定义切点
// 让所有有@LimitRequest注解的方法都执行切面方法
@Pointcut("@annotation(limitRequest)")
public void excudeService(LimitRequest limitRequest) {
}
@Around("excudeService(limitRequest)")
public Object doAround(ProceedingJoinPoint pjp, LimitRequest limitRequest) throws Throwable {
// 获得request对象
RequestAttributes ra = RequestContextHolder.getRequestAttributes();
ServletRequestAttributes sra = (ServletRequestAttributes) ra;
HttpServletRequest request = sra.getRequest();

// 获取Map对象， 如果没有则返回默认值
// 第一个参数是key， 第二个参数是默认值
ExpiringMap uc = book.getOrDefault(request.getRequestURI(), ExpiringMap.builder().variableExpiration().build());
Integer uCount = uc.getOrDefault(request.getRemoteAddr(), 0);

if (uCount >= limitRequest.count()) { // 超过次数，不执行目标方法
return "接口请求超过次数";
} else if (uCount == 0){ // 第一次请求时，设置有效时间
// /** Expires entries based on when they were last accessed */
// ACCESSED,
// /** Expires entries based on when they were created */
// CREATED;
uc.put(request.getRemoteAddr(), uCount + 1, ExpirationPolicy.CREATED, limitRequest.time(), TimeUnit.MILLISECONDS);
} else { // 未超过次数， 记录加一
uc.put(request.getRemoteAddr(), uCount + 1);
}
book.put(request.getRequestURI(), uc);
// result的值就是被拦截方法的返回值
Object result = pjp.proceed();
return result;
}

}