Hi everyone, I'm working with an API that requires...

# serialization

[Roberto Leinardi]

Hi everyone, I'm working with an API that requires sending a JSON like this as payload

{
  "draw": [
    {
      "dc": [
        28,
        4,
        3,
        "#FF0000"
      ]
    },
    {
      "dr": [
        20,
        4,
        4,
        4,
        "#0000FF"
      ]
    },
    {
      "dt": [
        0,
        0,
        "Hello",
        "#00FF00"
      ]
    }
  ]
}

where the dc, dr and dt can be in any order and amount inside the list, while their values are always the same amount and type (e.g. Int, Int, Int, String for dc and Int, Int, String, String for dt), but as a List.
I'm trying to use Maps and Sealed classes but so far I didn't get anywhere.
What would be the best and easiest way to generate this JSON with kotlinx.serialization? Btw, this is part of a way bigger JSON, but the rest of the JSON can be handled with a normal data class and some `List`s. Also, I only need to serialize it (send this as payload) and I do not have to deserialize it back, in case this could make things easier.

[Adam S]

it sounds like you're looking for tuples https://github.com/Kotlin/kotlinx.serialization/issues/1906

[Adam S]

if you're on JVM you can try ks3 - it has a helper function. See the test for an example https://github.com/Kantis/ks3/blob/v0.3.1/ks3-standard/src/jvmTest/kotlin/io/ks3/standard/TupleSerializerTest.kt

[Roberto Leinardi]

yeah I'm on JVM, I'll have a look thanks a lot for the hint 🙂

[Roberto Leinardi]

I got pretty close but, since I'm using sealed classes, I get this annoying type inside the JSON:

"draw":[
      {
         "dc":[
            "type":"io.ks3.Tuple(com.leinardi.kal.model.Draw.Circle)",
            28,
            4,
            3,
            "#FF0000"
         ]
      },
      {
         "dr":[
            "type":"io.ks3.Tuple(com.leinardi.kal.model.Draw.Rectangle)",
            20,
            4,
            4,
            4,
            "#0000FF"
         ]
      },
      {
         "dt":[
            "type":"io.ks3.Tuple(com.leinardi.kal.model.Draw.Text)",
            0,
            0,
            "Hello",
            "#00FF00"
         ]
      }
   ],

Does anyone know how could I get rid of it?

[Javier]

dc, dr and dt have always the same name?

[Roberto Leinardi]

@Javier yep, the name is always the same: https://blueforcer.github.io/awtrix-light/#/api?id=drawing-instructions

[Javier]

I would do custom serializers for that with simple data classes and using json objects and json arrays as implementation detail. The usage would be really simple compared to get the same with maps and sealed classes