public async Task <IActionResult> PostAuthor([FromBody] Author author)
        {
            if (!ModelState.IsValid)
            {
                return(BadRequest("Error verifique os campos e tente novamente mais tarde."));
            }

            var authorDb = await _authorsRepository.GetAuthorByNameAsync(author.Name);

            if (authorDb != null)
            {
                return(BadRequest("Já existe um autor com esse nome."));
            }

            await _authorsRepository.IncludeAsync(author);

            var uri = Url.Action("GetAuthor", new { id = author.Id });

            return(Created(uri, author));
        }