I have defined the following classes : ```interface DeviceAttribute<T> { val name: String ...

# serialization

[jean]

I have defined the following classes :

interface DeviceAttribute<T> {
    val name: String
    val value: T
}

@SharedImmutable
internal val module = SerializersModule {
    polymorphic(baseClass = DeviceAttribute::class, baseSerializer = null) {
        subclass(AlarmEntryDevice::class)
        default { Unknown.serializer() }
    }
}

@Serializable
data class Device(
    val id: String,
    val name: String,
    val icon: String,
    val iconOptions: List<String>,
    val attributes: List<DeviceAttribute<*>> = emptyList(),
    val profiles: List<ActiveProfileMode>?,
)

But I get this error Serializer has not been found for type 'Any?'. To use context serializer as fallback, explicitly annotate type or property with @Contextual Adding the annotation doesn’t change anything though. What should I do?

[Dominaezzz]

You should remove the generics from your interface since you don't seem to need it.

[jean]

it’s used in other parts of my app, I just wrote the relevant classes to the issue here

[Dominaezzz]

Well, you can't quite mix generics and polymorphism like you've done there.

[Dominaezzz]

How many possible values of T are there? Maybe you can hard code them? Like StringDeviceAttribute

[jean]

It could be any primitive type but I can do without it, it would have just been a bit nicer code. thanks for the help 🙂

[Dominaezzz]

It's just not possible for kotlinx.serialization to know which value of T to use when deserialising.

[Dominaezzz]

Np

[jean]

I understand that, I though maybe I needed to have some more configuration in the SerializersModule to fix it

[ephemient]

https://github.com/Kotlin/kotlinx.serialization/issues/607
kotlinx.serialization doesn't handle this well currently