public async Task DeleteFileAsync(string fileId)
{
AssertIdentityProvided(); // Quota is affected
var filePath = GetTargetFilePath(fileId);
var fileInfo = await Task.Run(() => new FileInfo(filePath));
var fileSize = fileInfo.Length;
await Task.Run(() => File.Delete(filePath));
if (_owner != null)
{
var lockEntry = ServerContext.ServiceTable[_owner].UserLock;
// Decrease user storage usage
await lockEntry.ObtainExclusiveWriteAsync();
var userManager = new WebUserManager(ServerContext);
var ownerData = await userManager.FindUserByUsernameAsync(_owner);
var prevStorageUsage = ownerData.StorageUsage;
ownerData.StorageUsage -= fileSize;
await userManager.UpdateUserInDatabaseAsync(ownerData);
lockEntry.ReleaseExclusiveWrite();
}
}
public async Task <FileUploadResult> HandleUploadAsync(string fileName, Stream stream)
{
AssertIdentityProvided(); // Quota is affected
var fileId = Guid.NewGuid().ToString();
var targetFile = GetTargetFilePath(fileId);
var uploadStreamFileSize = stream.Length;
try
{
// Write file (Wait for upload throttle)
await ServerContext.ServiceTable[_owner]
.UploadThrottle.WithResourceAsync(async() =>
{
using (var destinationStream = File.Create(targetFile))
{
await stream.CopyToAsync(destinationStream);
}
});
// Make sure user has enough space remaining
if (_owner != null)
{
var lockEntry = ServerContext.ServiceTable[_owner].UserLock;
await lockEntry.ObtainExclusiveWriteAsync();
var userManager = new WebUserManager(ServerContext);
var ownerData = await userManager.FindUserByUsernameAsync(_owner);
var afterUploadSpace = ownerData.StorageUsage + uploadStreamFileSize;
if (afterUploadSpace > ownerData.StorageQuota)
{
lockEntry.ReleaseExclusiveWrite();
// Throw exception, catch block will remove file and rethrow
throw new QuotaExceededException();
}
// Increase user storage usage
ownerData.StorageUsage += uploadStreamFileSize;
await userManager.UpdateUserInDatabaseAsync(ownerData);
lockEntry.ReleaseExclusiveWrite();
}
}
catch (QuotaExceededException)
{
// Roll back write
await Task.Run(() => File.Delete(targetFile));
throw;
}
return(new FileUploadResult
{
FileId = fileId,
Size = uploadStreamFileSize
});
}
