KT-API-4-CompleteMultipleAsync.kt

fun main(args: Array<String>) {
    val methodTime = measureTimeMillis {
        val apiResult = runBlocking(Dispatchers.Default) {
            val asyncResult1 = async { callApi() }
            val asyncResult2 = async { callApi() }
            val asyncResult3 = async { callApi() }
            listOf(asyncResult1, asyncResult2, asyncResult3).awaitAll()
        }
        println(apiResult)
    }

    println("Time: ${methodTime}ms")
}

fun callApi(): String {
    val client = OkHttpClient()

    val okRequest = Request.Builder()
        .url("https://httpbin.org/get")
        .build()
    val responseResource: Response = client.newCall(okRequest).execute()

    return responseResource.use {
        responseResource.body?.string()!!
    };
}