This repository contains an example of the Circuit Breaker pattern implementation in Android applications. You can also find the iOS implementation at RxCircuitBreaker-iOS
We have CircuitBreaker as a main component in the pattern, like this:
public class CircuitBreaker {
...
private CircuitBreaker(Builder builder) {
...
}
public <T> Single<T> callService(Single<T> service) {
switch (this.status) {
case OPEN:
return openActions();
case HALF_OPEN:
return halfOpenActions(service);
case CLOSED:
return closeActions(service);
default:
return service;
}
}
...
}For demonstration purposes, the events (reset - success) are separated in the half-open and closed states. However, the reader may notice that they are events that can be unified.
You also have the Rx wrapper for the service:
private Single<String> service(String typeSimulation) {
return Single.create(emitter ->
functions
.getHttpsCallable("simulateResponses?typeSimulation=" + typeSimulation)
.call()
.continueWith(task -> (String) Objects.requireNonNull(task.getResult()).getData())
.addOnCompleteListener(task -> {
if (task.isSuccessful()) {
emitter.onSuccess(Objects.requireNonNull(task.getResult()));
} else {
emitter.onError(Objects.requireNonNull(task.getException()));
}
}));
}Calling from the client, you could use something like this:
private void callServiceWithCircuitBreaker(String typeSimulation) {
...
CircuitBreaker circuitBreaker = circuitBreakerManager.getCircuitBreaker("circuit-breaker-9", localPersistence);
compositeDisposable.add(
CircuitBreakersManager.callWithCircuitBreaker(this.service(typeSimulation), circuitBreaker)
.subscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread())
.subscribe(response -> {
logs(response, circuitBreaker.getStatus().toString(), true);
...
},
throwable -> {
logs(throwable.getMessage(), circuitBreaker.getStatus().toString(), false);
...
}));
}
- Android Studio 4.1.1 - Java 8
- RxJava 3 - RxAndroid 3
- Activities - Layouts