Is there any way to define a serializer for a top-...

# serialization

[Shan]

Is there any way to define a serializer for a top-level list as a contextual serializer in a SerializersModule?

[Shan]

My options right now seem to be:
• wrap the list in a data class and then add that data class's serializer to the module
• check if it's a list in my stringify() call and use the built in .list extension function, but that would require reflection with how I'm doing it

[sandwwraith]

you need serializer for List<@Contextual MyData>? try ContextualSerializer(MyData::class).list

[Shan]

I have a Serializers Module like this:

internal val fooModule = SerializersModule {
    contextual(Foo::class, Foo.serializer())
    contextual(Bar::class, Bar.serializer())
    //etc
}

And I need to serialize a body that is a top-level list when I make a server request. My serialize function searches the serialization context I have defined in my library like so:

internal inline fun <reified T : Any> serialize(obj: T) = json.stringify(serializationContext.getContextualOrThrow(), obj)

internal val serializationContext = SerializersModule {
    include(
        fooModule + otherModule + otherModule2 //etc
    )
}

I can create a separate function for serializing a top-level list by adding it's specific serializer().list, but I was wondering if there is a way to add it to my SerializersModule using it's list serializer.

[Shan]

Right now I am doing this:

@Serializable
data class FooList(
    val foos: List<Foo>
) {
    @Serializer(FooList::class)
    companion object : KSerializer<FooList> {
        override val descriptor: SerialDescriptor = StringDescriptor.withName("FooList")

        override fun serialize(encoder: Encoder, obj: FooList) {
            Foo.serializer().list.serialize(encoder, obj.foos)
        }

        override fun deserialize(decoder: Decoder): FooList {
            return FooList(Foo.serializer().list.deserialize(decoder))
        }
    }
}

@Serializable
data class Foo(
    val name: String,
    val id: Int
)

And then adding both FooList and Foo serializers to my SerializersModule. It's just a bit tedious for anytime I want to serialize a top-level list.