MailSendingLimiter.scala

// generate cyclic sending mail wiht rotation on chosen data 
  private def generateMailsSending(sentmails: Meter): Cancellable = {

    import sys.process._

    val getNextHeaderSet: () => ClientHeaders = {
      def b(): Stream[ClientHeaders] = headers.toStream #::: b
      var cyclicIterator: Stream[ClientHeaders] = b()
      () => {
        val tail = cyclicIterator.tail
        val result = tail.head
        cyclicIterator = tail
        result
      }
    }
// requires sendmail and unix os host
    context.system.scheduler.schedule(Config.MAILS_DURATION, Config.MAILS_DURATION) {
      "echo anything" #| s"sendmail ${getNextHeaderSet().msisdn}@[$BASE_IP]" !;
      sentmails.mark()
    }
  }