Scala : Converting object having UUID field to Json returns blank

Question

Here is my case class that i want to convert to Json

case class Cart(cart_id :UUID, cart_entries :Map[String,CartEntry]){
}

I am using net.liftweb.json._

implicit val formats = UUID
val json = write(cart) //cart is Cart object with values for both attributes cart_id = 68eb787f-746c-4320-9ef4-8b5c7f0d7e21
println(json)

the json returns somthing like :

{"cart_id":{},"cart_entries":[{"_1":"ABC","_2":{"sku_id":"ABC","quantity":12,"price":{"bigDecimal":{},"mc":{}}}}]}

notice the value for cart_id is blank {} , I expect something like :

{"cart_id":{68eb787f-746c-4320-9ef4-8b5c7f0d7e21},"cart_entries":[{"_1":"ABC","_2":{"sku_id":"ABC","quantity":12,"price":{"bigDecimal":{},"mc":{}}}}]}

I have used other api's like fasterxml all return "" for UUID . How do i fix this ?

Answer 1

While your Cart is a case class composed of types for which lift-json provides serializers, the UUID class probably isn't (I assume you use java.util.UUID). Therefore you need to write your own serializer & deserializer, with something like this (untested):

     def serialize(implicit format: Formats): PartialFunction[Any, JValue] = {
       case x: UUID => JString(x.toString)
     }