[Rx] RxFirebaseRemoteConfig

RxFirebaseRemoteConfig.java

package com.milanuncios.milanunciosandroid.common.remoteconfig;

import com.alexsimo.toolbelt.optional.Optional;
import com.google.firebase.remoteconfig.FirebaseRemoteConfig;
import com.google.firebase.remoteconfig.FirebaseRemoteConfigSettings;
import com.milanuncios.milanunciosandroid.BuildConfig;
import java.util.Map;
import rx.AsyncEmitter;
import rx.Observable;

public class RxFirebaseRemoteConfig {

  private final Optional<Integer> defaultConfigurationFile;
  private final Optional<Map<String, Object>> defaultConfigurationMap;
  private FirebaseRemoteConfig remoteConfig;

  public RxFirebaseRemoteConfig(FirebaseRemoteConfigSettings settings, Integer defaultConfig) {
    this.defaultConfigurationFile = Optional.of(defaultConfig);
    this.defaultConfigurationMap = Optional.absent();
    init(settings);
  }

  public RxFirebaseRemoteConfig(FirebaseRemoteConfigSettings settings,
      Map<String, Object> defaultConfig) {
    this.defaultConfigurationFile = Optional.absent();
    this.defaultConfigurationMap = Optional.of(defaultConfig);
    init(settings);
  }

  public Observable<Boolean> refresh() {
    return Observable.fromEmitter(emitter -> remoteConfig.fetch(calculateCacheExpiration())
        .addOnSuccessListener(success -> refreshSuccess(emitter))
        .addOnFailureListener(emitter::onError), AsyncEmitter.BackpressureMode.LATEST);
  }

  public Observable<Boolean> getFreshBoolean(String key) {
    return refresh()
        .filter(refreshed -> refreshed)
        .flatMap(filtered -> getBoolean(key));
  }

  public Observable<Boolean> getBoolean(String key) {
    return Observable.fromCallable(() -> remoteConfig.getBoolean(key));
  }

  public Observable<String> getString(String key) {
    return Observable.fromCallable(() -> remoteConfig.getString(key));
  }

  public Observable<Long> getLong(String key) {
    return Observable.fromCallable(() -> remoteConfig.getLong(key));
  }

  private void init(FirebaseRemoteConfigSettings settings) {
    remoteConfig = FirebaseRemoteConfig.getInstance();
    remoteConfig.setConfigSettings(settings);
    defaultConfigurationPrecondition();
    setDefaultConfiguration();
  }

  private void refreshSuccess(AsyncEmitter<Boolean> emitter) {
    remoteConfig.activateFetched();
    emitter.onNext(true);
    emitter.onCompleted();
  }

  private void defaultConfigurationPrecondition() {
    if (noDefaultConfigurationAvailable()) {
      throw new IllegalArgumentException(
          "You need to specify at least one default configuration parameter");
    }
  }

  private boolean noDefaultConfigurationAvailable() {
    return !defaultConfigurationFile.isPresent() && !defaultConfigurationMap.isPresent();
  }

  private void setDefaultConfiguration() {
    if (defaultConfigurationFile.isPresent()) {
      remoteConfig.setDefaults(defaultConfigurationFile.get());
    } else {
      remoteConfig.setDefaults(defaultConfigurationMap.get());
    }
  }

  private long calculateCacheExpiration() {
    int ONE_MINUTE = 3600;
    long cacheExpiration = ONE_MINUTE;
    if (remoteConfig.getInfo().getConfigSettings().isDeveloperModeEnabled()) {
      cacheExpiration = 0;
    }
    return cacheExpiration;
  }

Done! Thanks for the notice @FireZenk!