尝试移除模板代码

template code.scala

// utils
class FromJsonQueryStringBindable[T] ()(implicit decoder: Decoder[T],
                                        encoder: Encoder[T]) extends QueryStringBindable[T] {
  implicit val binder: QueryStringBindable[Json] = JsonQueryStringBindable
  override def bind(key: String, params: Map[String, Seq[String]]): Option[Either[String, T]] =
    binder.bind(key, params).map(_.flatMap(_.as[T].left.map(_.message)))

  override def unbind(key: String, value: T): String = s"$key=${value.asJson}"
}

object JsonQueryStringBindable extends QueryStringBindable[Json] {
  override def bind(key: String, params: Map[String, Seq[String]]): Option[Either[String, Json]] =
    params.get(key).flatMap(_.headOption).map(parse(_).left.map(_.message))

  override def unbind(key: String, value: Json): String = s"$key=${value.toString}"
}

// models
case class CandidateFilter()
object CandidateFilter {
  implicit def queryStringBindable = new FromJsonQueryStringBindable[CandidateFilter]
}

case class Order[T]()
object Order {
  implicit def queryStringBindable[T] = new FromJsonQueryStringBindable[Order[T]]
}

case class Paging (size: Int = 10, number: Int = 1)
object Paging {
  implicit def queryStringBindable = new FromJsonQueryStringBindable[Paging]
}

//routes
GET     /api/open-candidates/           controllers.CandidateController.list(filter: models.CandidateFilter ?= new models.CandidateFilter, order: models.Order[com.mesoor.models.TenantTables.CandidateRow] ?= new models.Order[com.mesoor.models.TenantTables.CandidateRow], paging: models.Paging ?= new models.Paging()