Simple GET Request in Kotlin

app.kt

import com.squareup.moshi.JsonClass
import com.squareup.moshi.Moshi
import com.squareup.moshi.kotlin.reflect.KotlinJsonAdapterFactory
import okhttp3.OkHttpClient
import okhttp3.Request
import java.io.IOException

class ParseResponseWithMoshi {
    private val client = OkHttpClient()
    private val moshi = Moshi.Builder().add(KotlinJsonAdapterFactory()).build()
    private val gistJsonAdapter = moshi.adapter(Gist::class.java)

    fun run() {
        val request = Request.Builder()
            .url("https://api.nasa.gov/neo/rest/v1/neo/browse?api_key=DEMO_KEY")
            .build()
        client.newCall(request).execute().use { response ->
            if (!response.isSuccessful) throw IOException("Unexpected code $response")

            val gist = gistJsonAdapter.fromJson(response.body!!.source())

            for (key in gist!!.near_earth_objects!!) {
                println(key.name) // lists the name of every astronomical object near Earth
            }

        }
    }

    @JsonClass(generateAdapter = true)
    data class Gist(var near_earth_objects: List<GistFile>)

    @JsonClass(generateAdapter = true)
    data class GistFile(var name: String?)
}

fun main() {
    ParseResponseWithMoshi().run()
}