Hi! I try to make a request with a body of id’s. S...

# ktor

[dambakk]

Hi! I try to make a request with a body of id’s. So I have a serializable data class IdWrapper(val id: String) and set the body of the request to a list of IdWrapper instances. I though that should be it, but I get an exception saying “IdWrapper cannot be cast to String” when setting the `HttpRequestBuilder`’s body. Why is it expecting a String? Shouldn’t it accept Any serializable object?

[dambakk]

I have installed the JsonFeature and annotated the data class with Serializable. I have also tried to convert the list to json manually using Json.nonstrict.toJson(…) but this results in a JsonObject cannot be cast to String exception.

[corneil]

If you look at the specification HTTP bodies are String media type gives a hint of how to convert the string. A binary blob becomes base64 encoded string.

[dambakk]

I have already set Content-Type header to application/json. Anything else I should specify? All my other requests works fine, except this one which tries to set a List of objects as body.
@corneil

[dambakk]

I got it now… I had to wrap my list of objects in another object. E.g.:

data class IdObject(
  val id: String
)

data class IdList(
  val ids: List<IdObject>
)

Worked on first try 🙂

[dambakk]

(And write a custom serializer according to this: https://stackoverflow.com/questions/52971069/ktor-serialize-deserialize-json-with-list-as-root-in-multiplatform)