Is there anyway to know if a Job has been cancelled other than checking `isActive` or having a Cance...

# coroutines

[aerb]

Is there anyway to know if a Job has been cancelled other than checking isActive or having a CancellationException thrown?

[octylFractal]

what other way are you looking for?

[aerb]

A callback? Maybe I need to think more in coroutines. Bascially I want to subscribe to an Observable and keep the subscription until the Job is cancelled - after which is dispose.

[Zach Klippenstein (he/him) [MOD]]

you can call join(), which will suspend until the job completes or fails

[octylFractal]

there is invokeOnCompletion

[aerb]

right now I have a:

try {
delay(MAX_LONG)
} finally {
dispose()
}

[Zach Klippenstein (he/him) [MOD]]

but yea for that use case you probably want invokeOnCompletion

[octylFractal]

but depending on where the Observable comes from, there is well-tested adaptor libraries

[octylFractal]

https://github.com/Kotlin/kotlinx.coroutines/blob/master/reactive/README.md

[aerb]

I didn’t find anything in the kotlinx-reactive one

[Zach Klippenstein (he/him) [MOD]]

Where is the Job coming from?

[aerb]

Best i found was https://kotlin.github.io/kotlinx.coroutines/kotlinx-coroutines-rx2/kotlinx.coroutines.rx2/io.reactivex.-observable-source/open-subscription.html

But that does not appear to clean up correctly

[aerb]

It’s a Supervisor Job associated with a View

[Zach Klippenstein (he/him) [MOD]]

just turn it into a Flow and collect it from a coroutine that is a child of that job

[Zach Klippenstein (he/him) [MOD]]

openSubscription should work if you use consumeEach, but it is deprecated

[aerb]

I guess that is it

[Zach Klippenstein (he/him) [MOD]]

collect { } will cancel correctly if its coroutine is cancelled

[Zach Klippenstein (he/him) [MOD]]

and that will dispose the rx subscription

[aerb]

Thanks - Flow just didn’t feel like the right use-case here. The stream is not really lazy, but this will work.

[Zach Klippenstein (he/him) [MOD]]

and I believe asFlow() is stable as of coroutines 1.3.2

[aerb]

Oh I’m a couple versions behind 🙃

[aerb]

woops

[Zach Klippenstein (he/him) [MOD]]

Lazy or not, Flow is basically the official coroutines-friendly analogue to Rx now, so it’s probably the right use case.

[aerb]

Yeah - looks like it. 👍

[aerb]

I think you need to convert the Observable to Flowable first correct;/

[aerb]

I think you need to convert the Observable to a Flowable first correct?

[Zach Klippenstein (he/him) [MOD]]

Oh yea, that’s true