def search = Action(parse.json) { request =>
    val sR = request.body.validate[SearchRequest]
    sR.fold(
      errors => {
        BadRequest(Json.obj("status" -> "KO", "message" -> JsError.toJson(errors)))
      },
      searchRequest => {
        Logger.debug(s"searchRequest is $searchRequest")
        val sr = SearchResults(10)
        Ok(Json.toJson(sr))
      }
    )
  }

IsGreaThan
IsLessThan
EqualTo

case class SearchRequest(operator: String)

object SearchOperator extends Enumeration {
  type SearchOperator = Value

  val IsGreaThan = Value("IsGreaThan")
  val IsLessThan = Value("IsLessThan")
  val EqualTo = Value("EqualTo")
}

case class SearchRequest(lhs: Int, operator: SearchOperator, rhs:Int)

object SearchRequestJson {
  implicit val soReads = Reads.enumNameReads(SearchOperator)
  implicit val srReads = Json.reads[SearchRequest]
}

{ "lhs": 42, "operator": "NotEqualTo", "rhs": 44 }

JsError(
  List(
    (/operator, List(
      ValidationError(
        List(error.expected.enumstring),
        WrappedArray()
      )
    ))
  )
)