Kotlin coroutines adapter for google-maps-services-java (Google Maps API client)

GoogleMapsServicesCoroutineAdapter.kt

import com.google.maps.GeoApiContext
import com.google.maps.GeocodingApi
import com.google.maps.PendingResult
import kotlinx.coroutines.suspendCancellableCoroutine
import kotlin.coroutines.resume
import kotlin.coroutines.resumeWithException

/**
 * Coroutine adapter for Google Maps API future type [PendingResult]
 *
 * Can be used to perform asynchronous non-blocking calls to any Google Maps APIs
 *
 * Name of extension [awaitAsync] is chosen to avoid conflict with
 * a member method [PendingResult.await] which is a blocking API of [PendingResult]
 */
suspend fun <T> PendingResult<T>.awaitAsync(): T = suspendCancellableCoroutine { cont ->
    cont.invokeOnCancellation {
        cancel()
    }
    setCallback(object : PendingResult.Callback<T> {
        override fun onResult(result: T) {
            cont.resume(result)
        }

        override fun onFailure(e: Throwable) {
            cont.resumeWithException(e)
        }
    })
}

/**
 * Example of usage of [awaitAsync] extension to perform Geocoding request
 */
suspend fun main(args: Array<String>) {
    val apiKey = requireNotNull(args.elementAtOrNull(0)) {
        "First argument `API key` is not specified"
    }
    val address = requireNotNull(args.elementAtOrNull(1)) {
        "Second argument `Address` is not specified"
    }

    val result = GeocodingApi.geocode(
            GeoApiContext.Builder().apiKey(apiKey).build(),
            address
    ).awaitAsync().orEmpty()

    println(result.contentToString())
}