/// <summary>
/// The actual downloader
/// </summary>
/// <param name="fileDownloadInfo">Info of the file to download</param>
/// <returns>Exception, null if none</returns>
private void Download(FileDownloadInfo fileDownloadInfo)
{
var directoryName = Path.GetDirectoryName(fileDownloadInfo.LocalFile.ToString());
if (!Directory.Exists(directoryName))
{
Directory.CreateDirectory(directoryName);
}
var client = new WebClient();
try
{
client.DownloadFile(fileDownloadInfo.Url, fileDownloadInfo.LocalFile.ToString());
Logger.Info("Successfully downloaded {0} to {1}", fileDownloadInfo.Url, fileDownloadInfo.LocalFile);
return;
}
catch (Exception e)
{
if (fileDownloadInfo.Retries > 0)
{
Logger.TraceException(string.Format("Error while downloading {0} to {1}.", fileDownloadInfo.Url, fileDownloadInfo.LocalFile), e);
throw new FileDownloadRetryException();
}
else
{
Logger.ErrorException(string.Format("Error while downloading {0} to {1}. Giving up.", fileDownloadInfo.Url, fileDownloadInfo.LocalFile), e);
throw;
}
}
}
/// <summary>
/// Add a file to download to the queue
/// You have to subscribe to the <see cref="DownloadProgressNotification"/> event to get notified when the download is finished.
/// </summary>
/// <param name="uri">File to download</param>
/// <param name="localFile">Local path to download to</param>
/// <param name="identifier">Arbitrary identifier</param>
/// <param name="overwriteExistingFile">Overwrite an already existing file</param>
/// <param name="retries">Number of times to retry the download until we fail</param>
/// <param name="priority">Priority for the WorkItem</param>
public void AddDownload(Uri uri, FileInfo localFile, object identifier, bool overwriteExistingFile, int retries, WorkItemPriority priority)
{
var fileDownloadInfo = new FileDownloadInfo{ Url = uri, Identifier = identifier, LocalFile = localFile, Priority = priority, Retries = retries, OverwriteExistingFile = overwriteExistingFile };
lock (downloadThreadPoolLockObject)
{
downloadThreadPool.QueueWorkItem(this.DoWork, fileDownloadInfo, priority);
}
}
/// <summary>
/// Do it!
/// </summary>
/// <param name="fileDownloadInfo">Info of the file to download</param>
private void DoWork(FileDownloadInfo fileDownloadInfo)
{
Exception resultException = null;
try
{
if (fileDownloadInfo.LocalFile.Exists && !fileDownloadInfo.OverwriteExistingFile)
{
Logger.Warn("File {0} already exists. Skipping.", fileDownloadInfo.LocalFile);
resultException = new FileDownloadExistsException();
}
else
{
try
{
this.Download(fileDownloadInfo);
}
catch (FileDownloadRetryException)
{
lock (downloadThreadPoolLockObject)
{
downloadThreadPool.QueueWorkItem(this.DoWork, fileDownloadInfo, fileDownloadInfo.Priority);
}
return;
}
catch (Exception e)
{
resultException = e;
}
}
}
catch (Exception e)
{
resultException = e;
}
var eventArgs = new FileDownloadProgressEventArgs(fileDownloadInfo, resultException);
DownloadProgressNotification(this, eventArgs);
}
public FileDownloadProgressEventArgs(FileDownloadInfo fileDownloadInfo, Exception e)
{
this.FileDownloadInfo = fileDownloadInfo;
this.Exception = e;
}