Hey folks. I need to consume RxJS observables from...

# javascript

[John Fields]

Hey folks. I need to consume RxJS observables from KMP and wondering if anyone out there can offer advice or is aware of any samples, etc. I'm thinking about wrapping observerables in flows so they can be used higher in the stack in a standard fashion. I'm new to KMP and flows though, so don't know if there are any gotchas or if there's a better general approach.

[CLOVIS]

Something like this should get you started, but note that I can't test it at the moment.

fun Observable<T>.toFlow(): Flow<T> {
    val observable = this
    lateinit var subscription: Subscription

    return flow {
        subscription = observable.subscribe {
            emit(it)
        }
    }.onCompletion {
        subscription.unsubscribe()
    }
}

There is probably a nicer way to write this, but it should at least give you a starting point

[CLOVIS]

If anyone who knows coroutines more than I do wants to attempt this, here's what you need to know:

• Observable.subscribe takes a callback that is executed for each new element, starts immediately to process elements, and returns a Subscription
• Subscription.unsubscribe kills a subscription that is started

[John Fields]

Thanks @CLOVIS that looks like a good start. I'll give it a try!

[turansky]

For EventInstance we solve it via `Channel`, bacause emit requires suspend context.

[John Fields]

@turansky thank you. i was actually starting to look at channels.

[John Fields]

PS that repo looks like a treasure trove thanks for sharing that link!