trait with only case objects custom implementation in spray json

Question

Given I have the following declaration:

sealed trait Color
case object DColor extends Color
case object CColor extends Color
case object VColor extends Color

And then I use them In a case class like so:

case class CustomColor(c: Color)
CustomColor(VColor)

Now I want this to produce a JSON like so:

{c:"v_color"}

is your question about how to convert this case class to JSON or how to use that serializer in Spray? — yǝsʞǝla, Aug 06 '16 at 01:27

score 4 · Accepted Answer · answered Aug 06 '16 at 02:03

Should define a custom format:

object MyJsonProtocol extends DefaultJsonProtocol {
    implicit object ColorJsonFormat extends RootJsonFormat[Color] {
               def write(c: Color) = c match {
                  case VColor => JsString("v_color")
                  case _ => JsString("foo")
               }

               def read(value: JsValue) = ???
    }

    implicit val customColorFormat = jsonFormat1(CustomColor.apply)
}

Then

alex-alex@ import MyJsonProtocol._
alex-alex@ CustomColor(VColor).toJson
res18: JsValue = {"c":"v_color"}

trait with only case objects custom implementation in spray json

1 Answers1