object ServingError{
// we are adding a method modification content method, to be used by the modification traits  def modifyContent(error: ServingError, content: String): ServingError = {
   error match {
     case f: FatalError => FatalError(exceptionCause = f.exceptionCause, content = content)
     case i: InvalidRequestError => InvalidRequestError(i.paramName, i.paramValue, content = content)
   }
 }
}

trait JsonTransformer extends Sender {
 import ServingError._
 abstract override def send(event: ServingError): Unit = {
   super.send(modifyContent(event, {
     val date = event match {
       case d: DateTimestampedMessage => "\"date\":" + d.date
       case _ => ""
     }
     val cause = event match {
       case f: FatalError => "\"cause\":" + f.exceptionCause
       case i: InvalidRequestError => "\"cause\":" + i.paramName +":" +i.paramValue
     }
     s""" { "code:"${event.code}, $date $cause } """
   }))
 }
}
trait CsVTransformer extends Sender {
 import ServingError._
 abstract override def send(event: ServingError): Unit = {
   super.send(modifyContent(event, {
     val date = event match {
       case d: DateTimestampedMessage => d.date
       case _ => ""
     }
     val cause = event match {
       case f: FatalError => f.exceptionCause
       case i: InvalidRequestError => i.paramName +"," +i.paramValue
     }
     s"""${event.code},$date$cause"""
   }))
 }
}

trait Timestamp {
 val date: Date = new Date()
}