ratelimit.scala

class ApiService[T] {
  // other code ...
  
  def cleanupRequests() {
    val now = LocalDateTime.now()
    if (now.isAfter(nextCleanupTime)) {
      requestQueue.removeIf((req) => {
        val expired = req.startDeadline.exists(now.isAfter)
        if (expired) {
          req.p.complete(Failure(new TimeoutException))
        }
        expired
      })
      nextCleanupTime = now.plusSeconds(cleanupTimeFrame.toSeconds)
    }
  }
  
  private def tryRequest(): Unit = this.synchronized {
    cleanupRequests()
    // other code ...
  }
  
}