1.X: Why is CompletableSubscriber not a Subscription?

[bryant1410]

I see that CompletableSubscriber is not a Subscription, but Subcription is. So, when I use Completable#subscribe(CompletableSubscriber), I cannot then unsubscribe if I want to.

[akarnokd]

CompletableSubscriber was designed along the Reactive-Streams pattern where cancellation support is injected via onSubscribe call. Consumers extending CompletableSubscriber then can decide individually if they want to expose this cancellation support to the outside world by implementing Subscription themselves. In contrast, Subscriber can never revoke its ability to be unsubscribed externally.

If you are using subscribe() or the lambda versions of subscribe, you get a Subscription back. As for the subscribe(CompletableSubscriber), indeed we don't have a supporting class for it (as far as I remember). I'll post a PR for it today.

[akarnokd]

Closing via #4020.