/// <summary>
/// Handles post configuration setup
/// </summary>
public override void AfterConfigure()
{
base.AfterConfigure();
if (!Directory.Exists(SourceFolder))
{
Directory.CreateDirectory(SourceFolder);
}
m_filecache = new LRUCache <DateTime>(
sizelimit: MaxMirrorCacheSize,
countlimit: MaxMirrorCacheCount,
expirationHandler: TryDeleteAsync,
sizeHandler: TryFileSizeAsync
);
foreach (var f in Directory.EnumerateFiles(SourceFolder, "*", SearchOption.AllDirectories))
{
m_filecache.AddOrReplaceAsync(f, DateTime.Now + StartupMirrorCacheAgeSeconds).Wait();
}
m_404cache = new LRUCache <DateTime>(countlimit: Max404CacheCount);
}
/// <summary>
/// Downloads the file from the remote URL, signalling the progress task along the way
/// </summary>
/// <returns>An awaitable task.</returns>
/// <param name="context">The request context.</param>
/// <param name="localpath">The path to store the file at.</param>
private async Task DownloadRemoteFileAsync(IHttpContext context, string localpath, TaskCompletionSource <long> signal)
{
try
{
using (var resp = await GetRemoteStream(context))
{
lock (m_statuslock)
{
// Signal all others that we now know the full source length
m_activeTransferSizes[localpath] = resp.Size;
// And ensure the target folder exists
if (!Directory.Exists(Path.GetDirectoryName(localpath)))
{
Directory.CreateDirectory(Path.GetDirectoryName(localpath));
}
}
var pg = 0L;
using (var remote = resp.Stream)
using (var local = new FileStream(localpath, FileMode.Create, FileAccess.Write, FileShare.ReadWrite))
{
// Note: Since we write to the actual file,
// we may interfere with active downloads of
// the file...
int r;
var buffer = new byte[8 * 1024];
// Read some data
while ((r = await remote.ReadAsync(buffer, 0, buffer.Length)) > 0)
{
// Write it to the local file
await local.WriteAsync(buffer, 0, r);
await local.FlushAsync();
pg += r;
// Swap around and notify of the progress
var oldsignal = signal;
lock (m_statuslock)
m_activeTransfers[localpath] = (signal = new TaskCompletionSource <long>()).Task;
oldsignal.TrySetResult(pg);
}
}
// Update the file timestamp if possible
if (resp.LastModified.Ticks != 0)
{
try { File.SetLastWriteTime(localpath, resp.LastModified); }
catch { }
}
// Register that the file is now available as a normal file
await m_filecache.AddOrReplaceAsync(localpath, DateTime.Now);
// Now the cache returns the results, so we can unregister our callback
lock (m_statuslock)
{
m_activeTransferSizes.Remove(localpath);
m_activeTransfers.Remove(localpath);
}
// Prevent hanging followers
signal.TrySetResult(pg);
}
}
catch (Exception ex)
{
if (ex is HttpException he && he.StatusCode == HttpStatusCode.NotFound)
{
await m_404cache.AddOrReplaceAsync(localpath, DateTime.Now);
}
lock (m_statuslock)
{
m_activeTransferSizes.Remove(localpath);
m_activeTransfers.Remove(localpath);
}
signal.TrySetException(ex);
}
}