public Task <IEnumerable <IBook> > GetRandomBooks(int nubmerOfBooks)
        {
            var books = Task.Run(() => DataObjectFactory.Create <IBookDataObject>().GetRandomBooks(nubmerOfBooks));

            return(books);
        }
        public Task <IEnumerable <IBook> > GetBooksAsync(string searchString)
        {
            var books = Task.Run(() => DataObjectFactory.Create <IBookDataObject>().GetAllBooks(searchString));

            return(books);
        }
        public Task <Book> GetBooksAsync(int bookId)
        {
            var books = Task.Run(() => DataObjectFactory.Create <IBookDataObject>().Get(bookId));

            return(books);
        }
        public Task <IEnumerable <Book> > GetBooksAsync()
        {
            var books = Task.Run(() => DataObjectFactory.Create <IBookDataObject>().GetAll());

            return(books);
        }