/// <summary>
/// The actual functionality to download with optional hash verification
/// subclasses that wish to return the contents of the downloaded file
/// or do something else with it can override this instead of RunWithReturn.
/// </summary>
/// <param name="success"></param>
/// <returns></returns>
protected virtual NPath RunDownload(bool success)
{
Exception exception = null;
var attempts = 0;
bool result = false;
var partialFile = TargetDirectory.Combine(Filename + ".partial");
TargetDirectory.EnsureDirectoryExists();
do
{
exception = null;
if (Token.IsCancellationRequested)
{
break;
}
try
{
Logger.Trace($"Download of {Url} to {Destination} Attempt {attempts + 1} of {RetryCount + 1}");
using (var destinationStream = fileSystem.OpenWrite(partialFile, FileMode.Append))
{
result = Downloader.Download(Logger, Url, destinationStream,
(value, total) =>
{
UpdateProgress(value, total);
return(!Token.IsCancellationRequested);
});
}
if (result)
{
partialFile.Move(Destination);
}
}
catch (Exception ex)
{
exception = ex;
result = false;
}
} while (!result && attempts++ < RetryCount);
if (!result)
{
Token.ThrowIfCancellationRequested();
throw new DownloadException("Error downloading file", exception);
}
return(Destination);
}
