Hands-On Reactive Programming with Python

Operators – ref_count and share

There are cases wherein calling the connect method at the correct time is not easy, or is not necessary. In many cases, a cold observable can be converted to a hot observable whenever a first observer subscribes to it, as long as some subscriptions are ongoing. The ref_count operator does just that: it converts a cold observable to a hot observable as soon as a first subscription occurs. Its prototype is as follows:

ConnectableObservable.ref_count(self)

It is a method of the ConnectableObservable class. So, it must be used after a call to publish, as follows:

numbers = Observable.from_([1,2,3])pub_numbers = numbers.publish().ref_count()pub_numbers.subscribe(    on_next=lambda i: print("item: {}".format(i)), on_error=lambda ...