Hello All, I might be missing something but what i...

# flow

[jozefdransfield]

Hello All, I might be missing something but what is the difference between a flow generated from flow { … } and a ReceiveChannel.receiveAsFlow() im seeing some behavour i dont understand, namely if i create multiple new flows based on filters, the regular flow one receives all the messages, this isnt the case when they come from a receive channel.
I have a unit test to replicate what im seeing if it helps?

[Nick Allen]

When you write flow { emit(1); emit(2) } you are creating something that will run that lambda every time anything calls collect. Every collector will run code that emits a 1 and a 2.

When you call myChannel.receiveAsFlow(), it's the basically

flow {
    for(item in myChannel) {
        emit(item)
    }
}

Every collector is running the same code, but items are removed from the Channel as they are received so each collector gets its own separate items.

Consider:

var x = 0
val f = flow { x++; emit(x) }

Every collector would get a different value as x increases.

If you want to "share" the items of the Channel, you can share the resulting Flow :

myChannel.consumeAsFlow()
    .shareIn(scope, SharingStarted.WhileSubscribed())

which will only collect from the channel once. You'll want to adjust the started and replay params to fit your needs.