private async Task InitFileReceiveEndpoints(IWebServer server, FileSendInfo fileInfo, FileSendProgressCalculator transferProgress)
{
await fileInfo.InitSlicingAsync();
fileSliceSender = new FileSliceSender(fileInfo);
transferProgress.AddFileSliceSender(fileSliceSender);
fileSliceSender.SliceRequested += transferProgress.SliceRequestReceived;
for (int i = 0; i < fileInfo.SlicesCount; i++)
{
server.AddResponseUrl($"/{fileInfo.UniqueKey}/{i}/", (Func <IWebServer, RequestDetails, Task <byte[]> >)fileSliceSender.GetFileSlice);
}
}
private static async Task <IFile> CreateFile(FileSendInfo fileInfo, Guid sessionKey, IFolder downloadFolder)
{
var file = await FileHelper.CreateFile(downloadFolder, fileInfo.FileName);
if (file.Name != fileInfo.FileName) //File already existed, so new name generated for it. We should update database now.
{
await DataStorageProviders.HistoryManager.OpenAsync();
DataStorageProviders.HistoryManager.UpdateFileName(sessionKey, fileInfo.FileName, file.Name, downloadFolder.Path);
DataStorageProviders.HistoryManager.Close();
}
return(file);
}
private async Task DownloadFile(FileSendInfo fileInfo, IFolder downloadRootFolder, string serverIp, Guid sessionKey, CancellationToken cancellationToken)
{
//TODO: Add a semaphore or sth to make sure two threads don't start writing on one file.
IFolder downloadFolder = await FileHelper.CreateDirectoryIfNecessary(downloadRootFolder, fileInfo.RelativePath);
await DataStorageProviders.HistoryManager.OpenAsync();
var origFile = DataStorageProviders.HistoryManager.GetFileFromOriginalName(guid: sessionKey, originalFileName: fileInfo.FileName, path: downloadFolder.Path);
DataStorageProviders.HistoryManager.Close();
IFile file;
uint firstSliceToReceive = 0;
if (origFile.DownloadStarted == false)
{
file = await CreateFile(fileInfo, sessionKey, downloadFolder);
}
else if (origFile.Completed == true)
{
return;
}
else
{
file = await FileHelper.GetFile(downloadFolder, origFile.Name);
var stats = await file.GetFileStats();
if (stats.Length == (long)(fileInfo.SlicesCount * fileInfo.SliceMaxLength + fileInfo.LastSliceSize))
{
//It's already finished.
await DataStorageProviders.HistoryManager.OpenAsync();
DataStorageProviders.HistoryManager.MarkFileAsCompleted(sessionKey, file.Name, downloadFolder.Path);
DataStorageProviders.HistoryManager.Close();
return;
}
else if (stats.Length % (long)fileInfo.SliceMaxLength != 0)
{
//Invalid size. Will start over.
await file.DeleteAsync();
file = await CreateFile(fileInfo, sessionKey, downloadFolder);
firstSliceToReceive = 0;
}
else
{
firstSliceToReceive = (uint)(stats.Length / (long)fileInfo.SliceMaxLength);
if (firstSliceToReceive > 0)
{
progressCalculator.SliceReceived(fileInfo, firstSliceToReceive - 1);
}
}
}
ulong totalBytesReceived = 0;
using (var stream = await file.OpenAsync(PCLStorage.FileAccess.ReadAndWrite))
{
stream.Seek(stream.Length, SeekOrigin.Begin);
await DataStorageProviders.HistoryManager.OpenAsync();
DataStorageProviders.HistoryManager.SetDownloadStarted(sessionKey, file.Name, downloadFolder.Path);
DataStorageProviders.HistoryManager.Close();
for (uint i = firstSliceToReceive; i < fileInfo.SlicesCount; i++)
{
string url = $"http://{serverIp}:{Constants.CommunicationPort}/{fileInfo.UniqueKey}/{i}/";
if (cancellationToken.IsCancellationRequested)
{
throw new ReceiveCancelledException();
}
byte[] buffer = await HttpHelper.DownloadDataFromUrl(url, cancellationToken : cancellationToken);
if (cancellationToken.IsCancellationRequested)
{
throw new ReceiveCancelledException();
}
int expectedLength;
if (i == (fileInfo.SlicesCount - 1))
{
expectedLength = (int)(fileInfo.FileSize % fileInfo.SliceMaxLength);
}
else
{
expectedLength = (int)fileInfo.SliceMaxLength;
}
if (buffer.Length != expectedLength)
{
Debug.WriteLine("Slice length violation! Will retry...");
i--;
continue;
}
await stream.WriteAsync(buffer, 0, buffer.Length);
await stream.FlushAsync();
totalBytesReceived += (ulong)expectedLength;
progressCalculator.SliceReceived(fileInfo, i);
}
}
await DataStorageProviders.HistoryManager.OpenAsync();
DataStorageProviders.HistoryManager.MarkFileAsCompleted(sessionKey, file.Name, downloadFolder.Path);
DataStorageProviders.HistoryManager.Close();
}
internal void SliceReceived(FileSendInfo file, uint receivedSlice)
{
SliceReceived(file.UniqueKey, receivedSlice);
}
