/// <summary>
/// Transfers a file from the source FTP Server to the destination FTP Server via the FXP protocol asynchronously.
/// </summary>
private async Task <bool> TransferFileFXPInternalAsync(string sourcePath, FtpClient remoteClient, string remotePath, bool createRemoteDir, FtpRemoteExists existsMode,
IProgress <FtpProgress> progress, CancellationToken token, FtpProgress metaProgress)
{
FtpReply reply;
long offset = 0;
bool fileExists = false;
long fileSize = 0;
var ftpFxpSession = await OpenPassiveFXPConnectionAsync(remoteClient, progress != null, token);
if (ftpFxpSession != null)
{
try {
ftpFxpSession.SourceServer.ReadTimeout = (int)TimeSpan.FromMinutes(30.0).TotalMilliseconds;
ftpFxpSession.TargetServer.ReadTimeout = (int)TimeSpan.FromMinutes(30.0).TotalMilliseconds;
// check if the file exists, and skip, overwrite or append
if (existsMode == FtpRemoteExists.AppendNoCheck)
{
offset = await remoteClient.GetFileSizeAsync(remotePath, token);
if (offset == -1)
{
offset = 0; // start from the beginning
}
}
else
{
fileExists = await remoteClient.FileExistsAsync(remotePath, token);
switch (existsMode)
{
case FtpRemoteExists.Skip:
if (fileExists)
{
LogStatus(FtpTraceLevel.Info, "Skip is selected => Destination file exists => skipping");
//Fix #413 - progress callback isn't called if the file has already been uploaded to the server
//send progress reports
if (progress != null)
{
progress.Report(new FtpProgress(100.0, 0, 0, TimeSpan.FromSeconds(0), sourcePath, remotePath, metaProgress));
}
return(true);
}
break;
case FtpRemoteExists.Overwrite:
if (fileExists)
{
await remoteClient.DeleteFileAsync(remotePath, token);
}
break;
case FtpRemoteExists.Append:
if (fileExists)
{
offset = await remoteClient.GetFileSizeAsync(remotePath, token);
if (offset == -1)
{
offset = 0; // start from the beginning
}
}
break;
}
}
fileSize = await GetFileSizeAsync(sourcePath, token);
// ensure the remote dir exists .. only if the file does not already exist!
if (createRemoteDir && !fileExists)
{
var dirname = remotePath.GetFtpDirectoryName();
if (!await remoteClient.DirectoryExistsAsync(dirname, token))
{
await remoteClient.CreateDirectoryAsync(dirname, token);
}
}
if (offset == 0 && existsMode != FtpRemoteExists.AppendNoCheck)
{
// send command to tell the source server to 'send' the file to the destination server
if (!(reply = await ftpFxpSession.SourceServer.ExecuteAsync($"RETR {sourcePath}", token)).Success)
{
throw new FtpCommandException(reply);
}
//Instruct destination server to store the file
if (!(reply = await ftpFxpSession.TargetServer.ExecuteAsync($"STOR {remotePath}", token)).Success)
{
throw new FtpCommandException(reply);
}
}
else
{
//tell source server to restart / resume
if (!(reply = await ftpFxpSession.SourceServer.ExecuteAsync($"REST {offset}", token)).Success)
{
throw new FtpCommandException(reply);
}
// send command to tell the source server to 'send' the file to the destination server
if (!(reply = await ftpFxpSession.SourceServer.ExecuteAsync($"RETR {sourcePath}", token)).Success)
{
throw new FtpCommandException(reply);
}
//Instruct destination server to append the file
if (!(reply = await ftpFxpSession.TargetServer.ExecuteAsync($"APPE {remotePath}", token)).Success)
{
throw new FtpCommandException(reply);
}
}
var transferStarted = DateTime.Now;
long lastSize = 0;
var sourceFXPTransferReply = ftpFxpSession.SourceServer.GetReplyAsync(token);
var destinationFXPTransferReply = ftpFxpSession.TargetServer.GetReplyAsync(token);
// while the transfer is not complete
while (!sourceFXPTransferReply.IsCompleted || !destinationFXPTransferReply.IsCompleted)
{
// send progress reports every 1 second
if (ftpFxpSession.ProgressServer != null)
{
// send progress reports
if (progress != null && fileSize != -1)
{
offset = await ftpFxpSession.ProgressServer.GetFileSizeAsync(remotePath, token);
if (offset != -1 && lastSize <= offset)
{
long bytesProcessed = offset - lastSize;
lastSize = offset;
ReportProgress(progress, fileSize, offset, bytesProcessed, DateTime.Now - transferStarted, sourcePath, remotePath, metaProgress);
}
}
}
await Task.Delay(FXPProgressInterval);
}
FtpTrace.WriteLine(FtpTraceLevel.Info, $"FXP transfer of file {sourcePath} has completed");
await NoopAsync(token);
await remoteClient.NoopAsync(token);
ftpFxpSession.Dispose();
return(true);
}
// Fix: catch all exceptions and dispose off the FTP clients if one occurs
catch (Exception ex) {
ftpFxpSession.Dispose();
throw ex;
}
}
else
{
FtpTrace.WriteLine(FtpTraceLevel.Error, "Failed to open FXP passive Connection");
return(false);
}
}