public Envelope <NewsItemDto> GetAllNewsitems(int pageNumber, int pageSize)
        {
            var newsItems = _newsItemRepository.GetAllNewsItems().ToList();

            newsItems.ForEach(r => {
                var authorIds   = _newsItemRepository.GetAllAuthorIdByNewsItemId(r.Id).ToList();
                var categoryIds = _categoryRepository.GetAllCategoriesIdByNewsItemId(r.Id).ToList();

                r.Links.AddReference("self", $"api/{r.Id}");
                r.Links.AddReference("edit", $"api/{r.Id}");
                r.Links.AddReference("delete", $"api/{r.Id}");
                authorIds.ForEach(s => {
                    r.Links.AddReference("authors", $"api/authors/{s}");
                });
                categoryIds.ForEach(s => {
                    r.Links.AddReference("categories", $"api/authors/{s}");
                });
            });


            var envelope = new Envelope <NewsItemDto>(pageNumber, pageSize, newsItems);

            return(envelope);
        }