arktype•2mo ago

type for valid JSON value?

Is there a built-in or easy way to make sure a given input is a valid JSON value? Basically the opposite of type("string.json.parse") I guess

16 Replies

GenshiiOP•2mo ago

wait im blind object.json.stringify

ssalbdivad•2mo ago

Isn't it object.json

GenshiiOP•2mo ago

yeah idk how i missed that lol ty

ssalbdivad•2mo ago

No problem, always better when the solution already exists anyways 😅

GenshiiOP•2mo ago

Hmm this isn't working how I would expect

const jsonSchema = type("object.json")
const shouldBeArkErrors = jsonSchema(new Map())
if (shouldBeArkErrors instanceof type.errors) console.log(shouldBeArkErrors.summary)
// doesn't log

const jsonSchema = type("object.json")
const shouldBeArkErrors = jsonSchema(new Map())
if (shouldBeArkErrors instanceof type.errors) console.log(shouldBeArkErrors.summary)
// doesn't log

ssalbdivad•2mo ago

Hmm that's probably because new Map() doesn't have keys that don't belong to the prototype We could potentially add some restriction on a jsonifiable object that it has a prototype of null Object or Array- maybe open a GitHub issue? Because if you think about how an object is validated, it just iterates over its own keys, so in a case like that it would essentially be treating it as an empty object Would be pretty easy to add a .narrow shallowly but since it's recursive, probably easier to address internally

GenshiiOP•2mo ago

Yeah I think anything that's not assignable to the internal Json type should be rejected by object.json I'll open an issue

ssalbdivad•2mo ago

Yeah the difference is TS is checking the prototype as well whereas generally in validation this doesn't makes sense to do, but I can see how for this case it would be useful

GenshiiOP•2mo ago

Sort of related, but how do you feel about allowing json primitives? Currently object.json rejects something like 10 but that is also a valid Json value.

ssalbdivad•2mo ago

Well it definitely shouldn't be allowed for object.json But maybe I could provide the broader JSON type externally (it already exists internally)

GenshiiOP•2mo ago

oh right, thats for objects specifically yeah that would be awesome

ssalbdivad•2mo ago

Mostly just a matter of figuring out how I'd want to name/group the keyword Could add a top-level json I suppose

GenshiiOP•2mo ago

yeah i could see there being a json and json.stringify keyword

ssalbdivad•2mo ago

Feel free to open a request for that as well would be trivial to add

GenshiiOP•2mo ago

Can you point me to where this is? can't find it in the source