What is wrong w/ this CBOR code (1.0.0-RC, kotlin ...

# serialization

[TwoClocks]

What is wrong w/ this CBOR code (1.0.0-RC, kotlin ver : 1.4.10)
Throws the exception on the decode: kotlinx.serialization.cbor.internal.CborDecodingException: Expected start of array, but found BF

@Serializable
sealed class BaseClass()

@Serializable
data class TypeOne(val name:String) : BaseClass()

@Serializable
data class TypeTwo(val num:Int) : BaseClass()


@ExperimentalSerializationApi
fun main(args: Array<String>) {
    
    val bb = Cbor.encodeToByteArray(TypeOne("my name is mud"))

    val msg = Cbor.decodeFromByteArray<BaseClass>( bb )
    
    println(msg)

}

[TwoClocks]

actually, this doesn't work for json either.

fun main(args: Array<String>) {

    val bb = Json.encodeToString(TypeOne("my name is mud"))

    println(bb)

    val msg = Json.decodeFromString<BaseClass>( bb )

    println(msg)

}

throws kotlinx.serialization.json.internal.JsonDecodingException: Polymorphic serializer was not found for missing class discriminator ('null')

[TwoClocks]

do sealed classes, or something just not work at all? is there a workaround?

[TwoClocks]

nope... changed it to from sealed to open ... failure.

[TwoClocks]

it's not even trying to encode the type. do hierarchies just not work at all?

[TwoClocks]

getting major "amateur hour" vibes from this thing. Is this just a toy?

[Vampire]

No, it works fine. But if you need polymorphism you have to do explicitly afair. Did you read the docs about polymorphism?

[TwoClocks]

yes. the code looks pretty much identical. except for the use of data classes

[TwoClocks]

https://github.com/Kotlin/kotlinx.serialization/blob/1.0.0-RC/guide/example/example-poly-04.kt

[TwoClocks]

what's different?

[TwoClocks]

I just to this code :

[TwoClocks]

https://github.com/Kotlin/kotlinx.serialization/blob/1.0.0-RC/guide/example/example-poly-07.kt

[TwoClocks]

And altered one line `

val list = listOf(TextResponse("OK"))

and all the type information is gone.

[TwoClocks]

it's just [{"Test":"OK}}

[TwoClocks]

WTF....

[TwoClocks]

for polymorphic you must serialize no less than two in order for it to work?

[TwoClocks]

I can't use a SerializerModule because BaseClass or Response (from the docs) class is sealed / abstract.

[TwoClocks]

so.... not sure what you mean by "it works fine" except that it doesn't work fine.

[TwoClocks]

figured it out. You have to cast it to the base class.

[Vsevolod Tolstopyatov [JB]]

instead of cast, you also can use a (opionated) slightly more readable Cbor.encodeToByteArray<BaseClass>(TypeOne("my name is mud"))