:wave: Playing around with Values4k and http4k. S...

# http4k

[MrNiamh]

👋 Playing around with Values4k and http4k. Say I have quite a few IDs in my system, all done like this

class NoteId(value: UUID): AbstractValue<UUID>(value)

This seems to kind of work, however now it's returning in my API as:

"id" : {
         "value" : "00000000-0000-0000-0000-000000000000"
       }

Instead of what i'd prefer which is

"id" : "00000000-0000-0000-0000-000000000000"

I am trying to avoid adding each ID to my ConfigurableJackson as there's potentially quite a few. I tried to see where the AbstractValue was being auto-converted but couldn't see it anywhere in the ConfigurableJackson .

Not sure if i'm missing something obvious here.

[Andrew O'Hara]

Sadly, registering them all individually in your ConfigurableJackson is the best way I know of.

[James Richardson]

tbh - i tend to just list them - even if there are quite a few. doesn't take long. I also write a test that serializing all types that are a stringvalue that are in use don't put "value" in the json, so its all tested.

[dave]

You need to register them with the value() method in the JSON config. Also - each microtype should extend the relevant ValueTypeFactory for maximum ease.

[MrNiamh]

Dang that's unfortunate, well if I must - thanks

[Andrew O'Hara]

Yes, if you're extending the ValueFactory properly, you should have something like this:

class UserId private constructor(value: UUID): UuidValue(value) {
    companion object: UuidValueFactory<UserId>(::UserId)
}

val myJson = Jackson.custom {
    value(UserId)
}

[dave]

The ValueFactory is pretty important for taking advantage of validation and masking. Also - the main constructor should be private to enforce the usage of the UserId.of() for construction

[dave]

I've actually been thinking about it and wondering if there is a possibility that we could write a generic adapter to catch all of the value types. Will think a bit harder and see if it's possible...

[Andrew O'Hara]

If it's possible, it would allow me to delete almost all my custom marshallers!

[MrNiamh]

Haha i'm glad it troubles you too @dave, it felt like I was able to get something close but not quite there