What options exist for converting JSON schemas (not payloads) into Kotlin data classes? I have tested the JsonToKotlinClass plugin via IntelliJ which comes close, but it does not seem to interpret required / optional directives correctly. E.g. given a schema with two properties, one required and the other optional -

{
  "$schema": "<http://json-schema.org/draft-07/schema#>",
  "$id": "<https://abc.com/request.schema.json>",
  "title": "Request record",
  "type": "object",
  "properties": {
    "id": {
      "description": "The unique ID of a request",
      "type": "string"
    },
    "name": {
      "description": "The name of a request",
      "type": "string"
    }
  },
  "required": [
    "id"
  ]
}

I would expect to receive output like -

data class Request(
    val id: String,
    val name: String?
)

but instead, this is generated (both fields are marked as required) -

data class Request(
    val id: String,
    val name: String
)

Ideally I'd like to find a solution that can be implemented programatically too, rather than requiring a manual plugin (though that's not as important as getting the nullable part right).

Not that I know the answer, but out of curiosity want to ask a question: are json schemas a thing? Where do you encounter them in practice?

They're useful for defining the shape of data in projects where multiple systems will interact with the data (Kafka, spark, ML etc.) I think I found a way to make the plugin work, thanks for responding anyway.

Json schemas are a vital part of REST API Description and DDL technologies, like HATEOAS, OpenAPI, RAML, json:api, Apache Avro, etc. Moreover Json schemas should be used everywhere there is a Json data exchange, otherwise you’re missing the benefits of validation, versioning and elimination a whole class of bugs.

I’m curious of where they are used, not where they can be used. Do you have any big name REST API example that uses them?

all of Swagger and Open API ecosystem are based on it.

Example of it being <well-known-and-popular> REST API…?

Gotcha. It has many applications in practice - it's a large ecosystem including MSFT/AWS/Google all using it and having productized features around it in their various clouds.

Can you simply point to a website or webservice that uses it and which I can play with?

here's Stripe's open API spec. it uses/relies on JSON schema: https://github.com/stripe/openapi

@Sam Dozor will take a look for inspiration, thanks!