Is there a suggested way how to deal with one stat...

# ktor

[Florian]

Is there a suggested way how to deal with one status code having multiple possible response bodies in the openapi generator? E.g. 400 having data class TooManyParameters(val limit: Int = 0) and data class CustomReason(val reason: String)

Can I document the response twice and the generator merges it into a oneOf?

[Jonas]

I think you need to use a sealed hierarchy for that to work, something like that:

@Serializable
sealed interface BadRequestBody

@Serializable @SerialName("too-many-parameters")
data class TooManyParameters(val limit: Int = 0) : BadRequestBody

@Serializable @SerialName("custom-reason")
data class CustomReason(val reason: String) : BadRequestBody

[Aleksei Tirman [JB]]

To solve the problem, you can construct a JsonSchema explicitly with an oneOf . Here is an example:

get("/400") {
    call.respond(HttpStatusCode.BadRequest)
}.describe {
    responses {
        HttpStatusCode.BadRequest {
            schema = JsonSchema(oneOf = listOf(
                ReferenceOr.Value(jsonSchema<TooManyParameters>()),
                ReferenceOr.Value(jsonSchema<CustomReason>()),
            ))
        }
    }
}

[Florian]

Yeah the sealed hierarchy thing i did for 403, but for 400 documenting all BadRequest responses for every route would not describe my routes very well.

[Florian]

I guess then I'll use the .describe api (the KDoc one just reads a bit nicer)