Migrate client.identify() calls to use CompletableFuture<T>

[erawhctim]

Is your feature request related to a problem? Please describe.
It'd be nice if the LD SDK used CompletableFuture<T> (or if the internal Future impl. types LDAwaitFuture<T>, etc, implemented CompletionStage<T>) so that Kotlin apps could leverage the built-in conversion functions from kotlinx.coroutines.future to convert Future's to suspend fn's.

Right now, clients have to do this conversion manually:

suspend fun identifyInternal(): Unit = suspendCancellableCoroutine { continuation ->
  val future = client.identify(/* build a context */)
  continuation.invokeOnCancellation { future.cancel(/* mayInterruptIfRunning = */ true) }

  try {
    future.get()
    continuation.resume(Unit)
  } catch (e: ExecutionException) {
    continuation.resumeWithException(e.cause ?: e)
  } catch (e: InterruptedException) {
    continuation.resumeWithException(e)
  }
}

Ultimately it's not a ton of work to do this manually, but it'd be convenient to eliminate some of this boilerplate conversion code (if supporting CompletableFuture<T> is easy to do on your end).

Describe the solution you'd like
Supporting one of the above types. This would allow Kotlin clients to use kotlinx conversion functions like this:

suspend fun identifyInternal(): Unit {
  return client.identify(/* build a context */).await()
}

Describe alternatives you've considered
Continue doing the hand-written/manual conversion listed above.

Additional context
N/A

[tanderson-ld]

Hi @erawhctim, thank you for the feedback. I'm generally in agreement with you that a built in completable future should be used. Android added support for CompletableFuture in API 24 and our minimum API at the moment is 21. Does that sound correct? If so, I believe we'll have to wait until our min API is at least 24 before integrating this change.

[erawhctim]

🤦‍♂️ I totally forgot about the Android support side of this problem, yeah that makes sense (and sounds correct to my knowledge)

[tanderson-ld]

No worries! I'll leave this open as an enhancement as I'm sure other users will find your code snippet useful.