CryptocurrencyRepository.kt

class CryptocurrencyRepository @Inject constructor(val apiInterface: ApiInterface,
    val cryptocurrenciesDao: CryptocurrenciesDao, val utils: Utils) {

  fun getCryptocurrencies(limit: Int, offset: Int): Observable<List<Cryptocurrency>> {
    val hasConnection = utils.isConnectedToInternet()
    var observableFromApi: Observable<List<Cryptocurrency>>? = null
    if (hasConnection){
      observableFromApi = getCryptocurrenciesFromApi()
    }
    val observableFromDb = getCryptocurrenciesFromDb(limit, offset)

    return if (hasConnection) Observable.concatArrayEager(observableFromApi, observableFromDb)
    else observableFromDb
  }

  //...rest of the code
}