Add encode/decodeUuid to Encoder/Decoder

[hfhbd]

What is your use-case and why do you need this feature?

The uuid representation is often format specific. Json/StringFormats often uses the hexString representation, while binary formats like CBOR or Protobuf use a format specific representation, not a common one.

Currently, it is not possible to encode/decode a uuid value in a format specific representation per format as a format author.

It is only possible to use a custom format specific serializer if the user annotated the usage of kotlin.uui.Uuid with @Contextual and provided a custom serializer via SerializerModule.

Describe the solution you'd like
In Encoder/CompositeEncoder/Decoder/CompositeDecoder add encode/decodeUuid, with a default implementation that uses the Uuid.serializer() as fallback.
This allows other formats to override the method to implement a format specific uuid encoder/decoder.

interface Encoder {
  fun encodeUuid(value: Uuid) { UuidSerializer.serialize(this, value) }
}

interface Decoder {
  fun decodeUuid(): Uuid = UuidSerializer.deserialize(decoder = this)
}

Related:
#2730
hfhbd/kotlinx-uuid#422

[sandwwraith]

A typical solution to this problem is to check for descriptor in encodeSerializableValue, how it is done in Protobuf and Cbor, for example:

kotlinx.serialization/formats/cbor/commonMain/src/kotlinx/serialization/cbor/internal/Encoder.kt

Line 47 in 15b249e

&& serializer.descriptor == ByteArraySerializer().descriptor

[pdvrieze]

Alternatively, if you can't adjust the format, you can have a custom serializer that checks the encoder/decoder type and adjust accordingly (just make sure you make the serialKind contextual if there are underlying differences in the structure).