Finally, I found what causes the Exception and the issue address is flowing:

kotlin.coroutines.channels.awaitClose: JobCancellationException

Actually, awaitClose will not throw the JobCancellationException, because awaitClose is a cancellable suspended function. The offer method will throw JobCancellationException if the Job was canceled because offer is not a cancellable suspended function.

By the way, callbackFlow is an experimental API, so it may cause some bug, so when we use it, we need to be careful. Because it will not always ignore JobCancellationException when Job was canceled, and I don't think it's friendly to developers.

Now I have found 2 situations that will cause JobCancellationException so we need to try catch the exception.

1. async await, when we call the await method we need to try catch. And you can find and example in the Video.

2. callbackFlow offer, when we call the offer method we need to try catch. And you can find an example in the issue above.

I just saw the same problem. The issue was caused by the activity being finished manually before the job managed to complete.

class MyApp: Application() {

    override fun onCreate() {
        super.onCreate()
        System.setProperty(DEBUG_PROPERTY_NAME, DEBUG_PROPERTY_VALUE_ON)
       
    }

in this way you will be able to pinpoint the main cause of the issue an deal with it

I know I am late but you can just check Job Status before offering objects. Like this

if(isActive) offer(Resource.success(response))

isActive is Coroutine Scope

I have the same bug as you. So I try to write simple flow extensions like below:

fun <P> Flow<DataResult<P>>.safeStart(start: suspend FlowCollector<DataResult<P>>.() -> Unit)
        : Flow<DataResult<P>> =  onStart {
        if (!currentCoroutineContext().isActive) return@onStart
        start()
    }

fun <P> Flow<DataResult<P>>.safeCatch(onCatch: suspend FlowCollector<DataResult<P>>.(cause: Throwable) -> Unit)
        : Flow<DataResult<P>> = catch {
        if (!currentCoroutineContext().isActive) return@catch
        onCatch(it)
}

suspend inline fun <P> Flow<DataResult<P>>.safeCollect(crossinline onCollect: suspend (value: DataResult<P>) -> Unit)
        : Unit = collect {
    if (!currentCoroutineContext().isActive) return@collect
    onCollect(it)
}

I closed a ViewModel and a dialog and then started a Job. It led to this exception and HTTP-request cancellation: HTTP FAILED: java.io.IOException: Canceled.

close()
modelScope.launch {
    val response = withContext(Dispatchers.IO) {
        ...
    }
    response?.let { ... }
}

I simply moved close() to the end.

Had the same crash when I used callbackFlow with offer with coroutines version 1.3.5. Now instead of offer I use trySend and it's fixed.

Note: trySend method is available (and offer is deprecated) when you update coroutines version to:

org.jetbrains.kotlinx:kotlinx-coroutines-core:1.4.0