// Method: Get booklist from json (url) and Search for book by title or author, return list of Book
        public async Task <IEnumerable <IBook> > GetBooksAsync(string searchString)
        {
            var uri = "https://raw.githubusercontent.com/contribe/contribe/dev/arbetsprov-net/books.json";

            using (HttpClient httpClient = new HttpClient())
            {
                var response = await httpClient.GetAsync(uri);

                var jsonData = await response.Content.ReadAsStringAsync();

                BookCollection books = new BookCollection();

                if (!string.IsNullOrEmpty(jsonData))
                {
                    // Convert jsondata to a serie of objects
                    books = JsonConvert.DeserializeObject <BookCollection>(jsonData);
                }
                IEnumerable <IBook> searchResults = null;
                if (!String.IsNullOrWhiteSpace(searchString))
                {
                    searchResults = GetBookByTitleOrAuthor(searchString, books);
                }
                string session = JsonConvert.SerializeObject(searchResults);
                System.Web.HttpContext.Current.Session["searchResultsInSession"] = session;
                return(searchResults);
            }
        }
        // Method: Filter books by search string
        public IEnumerable <IBook> GetBookByTitleOrAuthor(string searchString, BookCollection bookstore)
        {
            IEnumerable <IBook> searchResults = null;

            if (!String.IsNullOrEmpty(searchString))
            {
                searchResults = bookstore.Books.Where(s => (s.Title.ToLower().Contains(searchString.ToLower())) || (s.Author.ToLower().Contains(searchString.ToLower()))).ToList();
            }
            return(searchResults);
        }