I’m reading official documentation on GitHub, and ...

# serialization

[Eugen Martynov]

I’m reading official documentation on GitHub, and it looks like I need to add SerialName to all implementations to serialise the sealed interface. However, when I try to test it, I see that serialiset is not found for the discriminator. Does it mean I have to define all subclasses when defining the serializable module?

[Dominaezzz]

You don't need to add it but it's good practice to do so. If the discriminator is missing then you're using the wrong serializer.

[Eugen Martynov]

There is class with this discriminator that serialiser looks like can not find

[Dominaezzz]

Do you have a code snippet?

[Eugen Martynov]

@Serializable
internal sealed class SocketMessage : BaseSocketMessage {...

@Serializable
@SerialName("typing")
internal data class TypingSocketMessage(...)

Error:

Polymorphic serializer was not found for class discriminator 'typing'

[Dominaezzz]

Shouldn't TypingSocketMessage extend SocketMessage ?

[Eugen Martynov]

It does

[Dominaezzz]

How are you serializing?

[Eugen Martynov]

private fun parseMessage(json: String): SocketMessage {
    return json.decodeFromString(json)

[Dominaezzz]

Nothing seems wrong from the snippets and messages. Create an issue with a reproducer.

[Eugen Martynov]

Super thank you for the validation

[Paul Woitaschek]

Can you try with an explicit SocketMessage.serializer()
It might be related to the serializer module

[Eugen Martynov]

I will try it tomorrow

[Eugen Martynov]

@Dominaezzz You were right the class was extending the different interface - we have around 35 these messages and this one only one was different

[Dominaezzz]

Ah nice! Glad you found the issue.