Apologies if this is in the worng channel ... I'm using kotlinx.serialization and

@Contextual

to de(serialize) Instant as a Long for my ktor server and I want to de(serialize) it as a Mongo Date for db operations. I am getting the expected behaviour when updating my document, but when I

insertOne

the documents instant is being serialized as a Long not a date (L22). When I later run

updateOne

the instant is being correctly serialised (L28). Any idea what I'm doing wrong here?

i had a similar issue not so long ago and wrote down what caused it for me, so you can take a look

I've got it to work as well but what's missing in my mental model, is where kmongo's instance of Json comes from? I explicitly configure contextual serializers for ktor, and so i understand why

call.recieve<T>()

can (de)serialize Instant <--> EpochMilliLong. But I don't see how to specify the contextual serializer for kmongo? Perhaps the

Json { ... }

configures a global singleton and so the ktor configuration block applies to both but then in that instant I would expect kmongo to serialize it as epoch milli 🤷 So how i have it working currently, is my ktor is configured as obove, I don't do anything to kmongo, and then I tag Instant as

@Contextual

which results in the desired behaviour