Sample.kt

import io.ktor.application.Application
import io.ktor.application.call
import io.ktor.application.install
import io.ktor.features.ContentNegotiation
import io.ktor.gson.gson
import io.ktor.request.receive
import io.ktor.routing.post
import io.ktor.routing.routing

fun Application.module() {

  install(ContentNegotiation) {
         gson { setPrettyPrinting() }
     }
     routing{
          post("items"){
              val items = call.receive<List<Item>>()
              val item = items[0]
          }
     }
}

data class Item(val name: String)