RxProxy

RxProxy is a simple way of creating Observables that can be fed values in a non-reactive way.

Build Status

Usage

Declare RxProxy as a member variable:

private final RxProxy<String> mTextStream = RxPublishProxy.create();

Publish on the proxy:

private void changeText(final String text) {
    mTextStream.publish(text);
}

Subscribe for the changes:

mTextStream.asObservable(Schedulers.computation())
           .filter(this::isValidText)
           .observeOn(AndroidSchedulers.mainThread())
           .subscribe(mTextView::setText);

Issues with Subjects

Subjects are really useful, but we have noticed some issues with them:

Publication and subscription do happen on the same thread. It does not matter if you are using subscribeOn. The subscription will be executed on the same thread from which onNext was called. This can be mitigated with observeOn but it changes the original pattern of the monad. RxProxy requires subscribers to define which Scheduler is used when receiving events from the proxy.
One can get confused when using onComplete and onError. Those can leave Subjects in a unusable state without making the user aware. In RxProxy a stream cannot be finished or report an error on its own. RxProxy just contains a publish method that is the equivalent of onNext.
Most Subjects do not support back-pressure. They immediately report an error whenever more items are delivered than requested. In RxProxy, each implementation has a small dedicated buffer that in the future we can control.

Credits

The project was inspired by reading a great series of blogs on RxJava by Dávid Karnok.

License

The MIT License (MIT)

Copyright (c) 2016 upday GmbH & Co. KG

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

keklikhasan / RxProxy