groupon/grox

Grox helps to maintain the state of Java / Android apps.

grox's Issues

Make snapshot deployment work with travis.

I have fixed the same issue in dependency-injection-checks in this commit:
groupon/dependency-injection-checks@234f330

travis secret is creating a bash environment variable, you need to reference that in gradle to make uploadArchives work.

Add full License

The license file we use is the short header for source files.
We should also have a long license which won't be checked by the license plugin.

explore using nebula plugins

core-rx and core-rx2 have class name collision when used in same project

Surprising as it may sound, I have a project with RxJava1/Grox Rx1 in one module, and RxJava2/Grox Rx2 in another. They work fine on their own, but when bringing them together, there's a collision as grox-core-rx and grox-core-rx2 use the same package and class name.

Most libraries solve this evolution problem by namespacing the Rx related classes under rx1 or rx2. Would this be something Grox would be willing to support?

setup code coverage

Would be nice to use https://codecov.io/ instead of coverall, at least give it a try.

Use KeepAChangelog v1.0.0 for CHANGELOG.md

http://keepachangelog.com/en/1.0.0/

Add grox icon to samples

to replace the default android app logo

Add maven badge to README

Change the sample to use concat instead of startWith

There is a subtle problem in your use of startWith() in LoginCommand.java: you use startWith() on the io() scheduler: that means, that the LogInProgressAction will not be emitted right away: so when you use this initial state to disable the login button, there is a possibility that the user presses the button twice.

So we should use concat:

Observable
  .just(LogInProgressAction)
  .concatWith( loginApiClient
    …
  )

clarify propagation and version number for release

It is working well but we have multiple version numbers in many build files, let's clean that up

StateChangeListener being called after unsubscribing [concurrency]

onStateChanged method from a StateChangeListener can be called after it has unsubscribe d.

Steps:

1. We have a Store S and Listener L.
2. In Thread 1, S starts notifying listeners using NotifySubscribersMiddleware .
3. CopyOnWriteArrayList is used to keep the listeners. Therefore, we iterate using a copy of the list that won't be changed during the iterator loop.
4. In Thread 2, L calls unsubscribe to unsubscribe from the Store S. This happens before step 3 is over and L is notified.
5. S notifies L calling onStateChanged, even thought it is already unsubscribed.

The scenario looks difficult to reproduce, however the consequences can be fatal.

Commands should return an Observable<? extends Action>

So we can have constructs like:

return qaDiscussionApiClient.getDiscussions(dealId)
            .map(UpdateQaPostCountAction::new)
            .onErrorResumeNext(empty());

State modification is visible too early to subscribers

if there are 2 subscribers (S0 & S1), and S0 modifies the state of the store in its RxChain, then S1 will see the state after modification by S1.

It shouldn't be llike this.
--> S0 & S1 should both see the original state and they both see the modified state after.

Grox doesn't notify anyone when an action produces an error when trying to change the state

Grox store don't call any listener / "subscriber of the states(store)" when an error happens during the action's newState method. The errors seem to just be swallowed by Grox.

Here is an example stackTrace:

at com.groupon.newdealdetails.local.grox.RefreshDealAction.newState(RefreshDealAction.java:47)
                                                                      at com.groupon.newdealdetails.local.grox.RefreshDealAction.newState(RefreshDealAction.java:16)
                                                                      at com.groupon.grox.Store$CallReducerMiddleware.intercept(Store.java:186)
                                                                      at com.groupon.grox.RealMiddlewareChain.proceed(RealMiddlewareChain.java:76)
                                                                      at com.groupon.misc.DebugMiddlewareChain.logStateAndAction(DebugMiddlewareChain.java:44)
                                                                      at com.groupon.misc.DebugMiddlewareChain.intercept(DebugMiddlewareChain.java:31)
                                                                      at com.groupon.grox.RealMiddlewareChain.proceed(RealMiddlewareChain.java:76)
                                                                      at com.groupon.grox.Store$NotifySubscribersMiddleware.intercept(Store.java:198)
                                                                      at com.groupon.grox.RealMiddlewareChain.proceed(RealMiddlewareChain.java:76)
                                                                      at com.groupon.grox.Store.emitSequentially(Store.java:86)
                                                                      at com.groupon.grox.Store.dispatch(Store.java:79)
                                                                      at com.groupon.newdealdetails.local.LocalDealDetailsFragment$$Lambda$10.call(Unknown Source:4)
                                                                      at rx.internal.util.ActionSubscriber.onNext(ActionSubscriber.java:39)
                                                                      at rx.observers.SafeSubscriber.onNext(SafeSubscriber.java:134)
                                                                      at rx.internal.operators.OnSubscribeOnAssembly$OnAssemblySubscriber.onNext(OnSubscribeOnAssembly.java:124)
                                                                      at rx.observers.SerializedObserver.onNext(SerializedObserver.java:91)
                                                                      at rx.observers.SerializedSubscriber.onNext(SerializedSubscriber.java:94)
                                                                      at rx.internal.operators.OnSubscribeConcatMap$ConcatMapSubscriber.innerNext(OnSubscribeConcatMap.java:182)
                                                                      at rx.internal.operators.OnSubscribeConcatMap$ConcatMapInnerSubscriber.onNext(OnSubscribeConcatMap.java:335)
                                                                      at rx.internal.operators.OnSubscribeOnAssembly$OnAssemblySubscriber.onNext(OnSubscribeOnAssembly.java:124)
                                                                      at rx.internal.producers.SingleProducer.request(SingleProducer.java:65)
                                                                      at rx.internal.producers.ProducerArbiter.setProducer(ProducerArbiter.java:126)
                                                                      at rx.internal.operators.OnSubscribeConcatMap$ConcatMapInnerSubscriber.setProducer(OnSubscribeConcatMap.java:329)
                                                                      at rx.Subscriber.setProducer(Subscriber.java:205)
                                                                      at rx.internal.operators.SingleLiftObservableOperator$WrapSubscriberIntoSingle.onSuccess(SingleLiftObservableOperator.java:76)
                                                                      at rx.internal.operators.OnSubscribeOnAssemblySingle$OnAssemblySingleSubscriber.onSuccess(OnSubscribeOnAssemblySingle.java:70)
                                                                      at rx.internal.operators.SingleOnErrorReturn$OnErrorReturnsSingleSubscriber.onSuccess(SingleOnErrorReturn.java:61)
                                                                      at rx.internal.operators.OnSubscribeOnAssemblySingle$OnAssemblySingleSubscriber.onSuccess(OnSubscribeOnAssemblySingle.java:70)
                                                                      at rx.internal.operators.SingleOnSubscribeMap$MapSubscriber.onSuccess(SingleOnSubscribeMap.java:74)
                                                                      at rx.internal.operators.OnSubscribeOnAssemblySingle$OnAssemblySingleSubscriber.onSuccess(OnSubscribeOnAssemblySingle.java:70)
                                                                      at rx.internal.operators.SingleDoOnEvent$SingleDoOnEventSubscriber.onSuccess(SingleDoOnEvent.java:63)
                                                                      at rx.internal.operators.OnSubscribeOnAssemblySingle$OnAssemblySingleSubscriber.onSuccess(OnSubscribeOnAssemblySingle.java:70)
                                                                      at rx.Single$13$1$1.onSuccess(Single.java:2021)
                                                                      at rx.internal.operators.OnSubscribeOnAssemblySingle$OnAssemblySingleSubscriber.onSuccess(OnSubscribeOnAssemblySingle.java:70)
                                                                      at rx.internal.operators.SingleFromCallable.call(SingleFromCallable.java:48)
                                                                      at rx.internal.operators.SingleFromCallable.call(SingleFromCallable.java:29)
                                                                      at rx.internal.operators.OnSubscribeOnAssemblySingle.call(OnSubscribeOnAssemblySingle.java:47)
                                                                      at rx.internal.operators.OnSubscribeOnAssemblySingle.call(OnSubscribeOnAssemblySingle.java:28)
                                                                      at rx.Single.subscribe(Single.java:1967)
                                                                      at rx.Single$13$1.call(Single.java:2039)
                                                                      at rx.internal.schedulers.CachedThreadScheduler$EventLoopWorker$1.call(CachedThreadScheduler.java:230)
                                                                      at rx.internal.schedulers.ScheduledAction.run(ScheduledAction.java:55)
                                                                      at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:457)
                                                                        at java.util.concurrent.Futu

Relicense to AL2

Action should be queued

Following a fix for issue

Setup travis CI

Generic Commands?

I am curious why Command does not make use of generics like Action does. Wouldn't it be better to define Command like this?

public interface Command<STATE> {
  Observable<? extends Action<STATE> actions();
}