Api.java

public static Observable<String> getUserInfo(final Context context,
                                             final String userId) {
	return Observable.create(new ObservableOnSubscribe<String>() {
		@Override
		public void subscribe(ObservableEmitter<String> subscriber) throws Exception {
			try {
				HttpUrl url = new HttpUrl.Builder()
						.scheme(SCHEME_HTTPS)
						.host(API_HOST)
						.addPathSegment(API_VERSION).addPathSegment(MODULE_NAME).addPathSegment(PATH_GET_USER_INFO)
						.addQueryParameter(User.FIELD_USER_ID, userId)
						.build();
				subscriber.onNext(ApiService.get(context, url));
			}
			catch (Exception e) {
				subscriber.onError(e);
			}
		}
	});
}

ApiService.java

public static String get(Context context, HttpUrl url) throws IOException {
	Request request = ApiService.createRequestBuilder(context)
			.url(url)
			.build();
	return ((GlobalContext) context.getApplicationContext())
			.getHttpClientDebug(HttpLoggingInterceptor.Level.BODY)
			.newCall(request)
			.execute().body().string();
}

GlobalContext.java

public OkHttpClient getHttpClientDebug(HttpLoggingInterceptor.Level debugLevel) {
	if (isDebugMode())
		return new OkHttpClient.Builder()
				.addInterceptor(new HttpLoggingInterceptor().setLevel(debugLevel))
				.addNetworkInterceptor(new StethoInterceptor())
				.build();
	else
		return getHttpClient();
}