Given a class `data class Node<T: Any>(val id: String, val type: String, val value: T)` , is i...

# serialization

[aarjav]

Given a class data class Node<T: Any>(val id: String, val type: String, val value: T) , is it possible to deserialize value based on the type field?

[gildor]

yes, see documentation for polymorphic deserialization
https://github.com/Kotlin/kotlinx.serialization/blob/master/docs/polymorphism.md

[aarjav]

Thanks for the quick response. Perhaps I'm reading it wrong but I don't see any examples matching my use case. I do not want multiple implementations of the Node class, and I do not control objects of type T (3rd party classes). So the type information of the value property I want to keep external to the instance.

[aarjav]

I would also like to later put them in a container class data class Graph<T: Any>(val nodes: List<Node<out T>>)

[gildor]

not sure that this use case supported directly, with generic List, but maybe you could have a base class Node<T> and particular implementation NodeFoo, NodeBar, it already supported with custom serializer registration

[gildor]

actually this looks like what you need:
https://github.com/Kotlin/kotlinx.serialization/blob/master/docs/polymorphism.md#polymorphism-and-generic-classes

[aarjav]

Thanks, I will try it out in unit test but I'm wondering how it will know the type without it being present in the json

[gildor]

But type is presented in Node, so parent will pass type to child serializer

[sandwwraith]

See also https://github.com/Kotlin/kotlinx.serialization/blob/master/docs/json.md#content-based-polymorphic-deserialization