Is there anyway to override the default polymorphic serialization for sealed classes? I’d like to re...

# serialization

[Sam Garfinkel]

Is there anyway to override the default polymorphic serialization for sealed classes? I’d like to redefine how subclasses are disambiguated.

[edenman]

on a global basis, not that i know of

[edenman]

on a one-off basis, certainly

[edenman]

@Serializable(with = MyCustomSerializer::class)

[edenman]

in my case, the trick with doing custom sealed class deserialization was to decode as a raw JsonObject, then check which class implementation is present, then decode that one

[edenman]

val input =
      decoder as? JsonInput ?: throw SerializationException("This class can be loaded only by Json")
    val tree =
      input.decodeJson() as? JsonObject ?: throw SerializationException("Expected JsonObject")
    fieldNameToSerializer.forEach { (name, serializer) ->
      if (tree.containsKey(name)) {
        return input.json.fromJson(serializer, tree)
      }
    }
    return unknown

[edenman]

(handling protobuf oneof over json where there’s no type field, just a “one of these fields will be set” approach)

[Sam Garfinkel]

Gotcha, thanks