/// <remarks>
/// Use it at reorgs.
/// </remarks>
public void TryRemove(uint256 hash)
{
using (BlocksFolderLock.Lock())
using (BlocksToDownloadLock.Lock())
{
if (BlocksToDownload.Contains(hash))
{
BlocksToDownload.Remove(hash);
}
var filePaths = Directory.EnumerateFiles(BlocksFolderPath);
var fileNames = filePaths.Select(x => Path.GetFileName(x));
var hashes = fileNames.Select(x => new uint256(x));
if (hashes.Contains(hash))
{
File.Delete(Path.Combine(BlocksFolderPath, hash.ToString()));
}
}
}
public void Start()
{
Interlocked.Exchange(ref _running, 1);
Task.Run(async() =>
{
while (IsRunning)
{
try
{
// If stop was requested return.
if (IsRunning == false)
{
return;
}
// If no connection, wait then continue.
if (Nodes.ConnectedNodes.Count == 0)
{
await Task.Delay(10);
continue;
}
if (IsRunning == false)
{
return;
}
uint256 hash = null;
// If nothing to download, wait then continue.
using (BlocksToDownloadLock.Lock())
{
if (BlocksToDownload.Count == 0)
{
await Task.Delay(100);
continue;
}
else
{
hash = BlocksToDownload.First();
}
}
if (IsRunning == false)
{
return;
}
Node node = Nodes.ConnectedNodes.RandomElement();
if (node == default(Node))
{
await Task.Delay(10);
continue;
}
if (!node.IsConnected)
{
await Task.Delay(10);
continue;
}
Block block = null;
try
{
using (var cts = new CancellationTokenSource(TimeSpan.FromSeconds(32))) // ADSL 512 kbit/s 00:00:32
{
block = node.GetBlocks(new uint256[] { hash }, cts.Token)?.Single();
}
if (block == null)
{
Logger.LogInfo <BlockDownloader>($"Disconnected node, because couldn't parse received block.");
node.DisconnectAsync("Couldn't parse block.");
continue;
}
if (!block.Check())
{
Logger.LogInfo <BlockDownloader>($"Disconnected node, because block invalid block received.");
node.DisconnectAsync("Invalid block received.");
continue;
}
}
catch (TimeoutException)
{
Logger.LogInfo <BlockDownloader>($"Disconnected node, because block download took too long.");
node.DisconnectAsync("Block download took too long.");
continue;
}
catch (OperationCanceledException)
{
Logger.LogInfo <BlockDownloader>($"Disconnected node, because block download took too long.");
node.DisconnectAsync("Block download took too long.");
continue;
}
catch (Exception ex)
{
Logger.LogDebug <BlockDownloader>(ex);
Logger.LogInfo <BlockDownloader>($"Disconnected node, because block download failed: {ex.Message}");
node.DisconnectAsync("Block download failed.");
continue;
}
using (BlocksFolderLock.Lock())
using (BlocksToDownloadLock.Lock())
{
BlocksToDownload.Remove(hash);
var path = Path.Combine(BlocksFolderPath, hash.ToString());
await File.WriteAllBytesAsync(path, block.ToBytes());
}
}
catch (Exception ex)
{
Logger.LogDebug <BlockDownloader>(ex);
}
}
}
);
}