Testrepo

class MainRepoImpl(private val api: ApiService) : IMainRepo {
    val TAG: String = javaClass.simpleName
    var isFirst = false
    var cache = Observable.empty<Message>()

    override
    fun loadData(): Observable<Message> {
        if (!isFirst) {
            cache = api.loadIp()
                    .subscribeOn(Schedulers.io())
                    .filter { (origin) -> origin.isNotEmpty() }
                    .observeOn(AndroidSchedulers.mainThread())
                    .doOnError { t -> Log.d(TAG, t.message) }
                    .cache()
            isFirst = true
        }
        return cache
    }

}