trait ServingError{
 val code: Int
 val description: String
}
case class FatalError(override val code: Int = 1, exceptionCause: String) extends ServingError {
 override val description: String =  s"Fatal Error code $code accrued"
}
case class InvalidRequestError(paramName: String, paramValue: String, override val code: Int = 2) extends ServingError{
 override val description: String = s"Invalid Request. Bad parameter: $paramName" + " " + s"with value: $paramValue"
}