I saw it’s possible to customize the value of the ...

# serialization

[bbaldino]

I saw it’s possible to customize the value of the type field when serializing polymorphic classes…I’m curious if it’s possible to customize the name of that field (type) via an annotation? Or would that require a custom serializer?

[ephemient]

https://kotlin.github.io/kotlinx.serialization/kotlinx-serialization-json/kotlinx.serialization.json/-json-class-discriminator/index.html

[ephemient]

or https://kotlin.github.io/kotlinx.serialization/kotlinx-serialization-json/kotlinx.serialization.json/-json-builder/class-discriminator.html for all types

[bbaldino]

thank you!

[bbaldino]

Hm, even with the experimental opt-in enabled, it doesn’t seem to be working for me.

[ephemient]

@Serializable
@JsonClassDiscriminator("kind")
sealed class Foo {
    @Serializable
    object One : Foo()
}
Json.encodeToString<Foo>(Foo.One) // => {"kind":"One"}

or

@Serializable
sealed class Bar {
    @Serializable
    object Two : Bar()
}
val json = Json {
    classDiscriminator = "kind"
}
json.encodeToString<Bar>(Bar.Two) // => {"kind":"Two"}

[bbaldino]

d’oh, i’m an idiot…put the annotation on the wrong class. thanks @ephemient.