Is it possible to choose a `Serializer` to handle a `JsonObject` ? I would like to achieve `String`...

# serialization

[Daniel Perez]

Is it possible to choose a Serializer to handle a JsonObject ? I would like to achieve String -> JsonObject -> Logic with when statement -> *MyChosenClass* . Thank you.

[jw]

What type is the property in your model? MyChosenClass? or JsonObject?

It sounds like you're describing a normal delegating KSerializer<MyChosenClass> where the delegate is JsonObject.serializer()

[Daniel Perez]

MyChosenClass is the property I'm trying to get to after evaluating a typeId from its wrapper class. So

@Serializable(WrapperSerializer::class)
data class Wrapper(
    val typeId: Long,
    val myChosenClass: MyChosenClass,
)

The logic I mentioned is occurring inside the WrapperSerializer. I can get the JsonObject just fine, it's just after I've identified which serializer to use, I'm not sure how to apply it to a JsonObject

[Alex Rouse]

JsonContentPolymorphicSerializer may be what you are looking for https://kotlinlang.org/api/kotlinx.serialization/kotlinx-serialization-json/kotlinx.serialization.json/-json-content-polymorphic-serializer/

[Daniel Perez]

Maybe, I'm looking into that right now and have used it before, but maybe I just need to readjust my thinking.

As for what the path I was going down, I was trying to achieve this inside the serializer.

when(typeId) {
    1 -> Wrapper(typeId = typeId, myChosenClass = decoder.decode(MyChosenClass.Subclass1.serializer(jsonObject)))
}

[jw]

You don't want to use the Decoder because you're not reading from the original JSON but from a model object

[jw]

You want like json.decodeFromJsonElement(serializer, jsonObject)

[jw]

that is saying, use the same json format as the source, use the chosen serializer of the chosen subclass, and use jsonObject as the model from which to bind properties. There's no actual serialized JSON decoding happening here.

[Daniel Perez]

I think I see what you're saying. Will I have to manually bind the properties from jsonObject into my chosen subclass though? I was trying to avoid that since there's quite a few subclasses and I just wanted to select the serializer from the typeId .

[jw]

That call will give you back an instance of your chosen subclass

[Daniel Perez]

Gotcha, I was able to get this moving. Thanks a ton to both of you