public async Task UpdateBookAsync(string userId, int bookId, BookUpdateDto model)
{
Book book = null;
Stream bookStream = null;
using (var transaction = await _context.Database.BeginTransactionAsync())
{
try
{
book = await GetBookForUserAsync(userId, bookId);
if (!String.IsNullOrEmpty(model.Author) || !String.IsNullOrEmpty(model.Title) ||
(model.PublishingDate != null && model.PublishingDate.HasValue))
{
bookStream = await DownloadBookAsync(userId, bookId, book.FileName);
bookStream.Position = 0;
var mobiDocument = await MobiService.GetMobiDocument(bookStream);
var editedBookStream = await UpdateMobiMetadata(mobiDocument, model);
editedBookStream.Position = 0;
await _storageService.UploadBookAsync(editedBookStream, userId, bookId, book.FileName);
book.HasBeenEdited = true;
book.LastEditDate = DateTime.Now.ToUniversalTime();
}
await UpdateBookDb(book, model);
transaction.Commit();
}
catch (DbException e)
{
transaction.Rollback();
bookStream.Position = 0;
var mobiDocument = await MobiService.GetMobiDocument(bookStream);
var editedBookStream = await UpdateMobiMetadata(mobiDocument, new BookUpdateDto { Title = book.Title, Author = book.Author });
await _storageService.UploadBookAsync(editedBookStream, userId, book.Id, book.FileName);
_logger.LogCritical(e.ToString());
throw;
}
}
}
private static async Task <MobiMetadaDto> GetMobiMetadataAsync(Stream stream)
{
MobiMetadaDto mobiMetada = new MobiMetadaDto();
var mobiDocument = await MobiService.GetMobiDocument(stream);
mobiMetada.Author = mobiDocument.Author;
mobiMetada.Title = mobiDocument.Title;
mobiMetada.PublishingDate = (mobiDocument.PublishingDate.HasValue) ?
mobiDocument.PublishingDate?.ToUniversalTime() :
null;
mobiMetada.Isbn = mobiDocument.ISBN;
var coverStream = mobiDocument.CoverExtractor.Extract();
if (coverStream != null)
{
mobiMetada.CoverStream = coverStream;
}
return(mobiMetada);
}