public async Task <int> CountBlocksAsync()
{
using (await BlockFolderLock.LockAsync())
{
return(Directory.EnumerateFiles(BlocksFolderPath).Count());
}
}
/// <remarks>
/// Use it at reorgs.
/// </remarks>
public async Task DeleteBlockAsync(uint256 hash)
{
using (await BlockFolderLock.LockAsync())
{
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()));
}
}
}
/// <exception cref="OperationCanceledException"></exception>
public async Task <Block> GetOrDownloadBlockAsync(uint256 hash, CancellationToken cancel)
{
// Try get the block
using (await BlockFolderLock.LockAsync())
{
foreach (var filePath in Directory.EnumerateFiles(BlocksFolderPath))
{
var fileName = Path.GetFileName(filePath);
if (hash == new uint256(fileName))
{
var blockBytes = await File.ReadAllBytesAsync(filePath);
return(Block.Load(blockBytes, IndexDownloader.Network));
}
}
}
cancel.ThrowIfCancellationRequested();
// Download the block
Block block = null;
using (await BlockDownloadLock.LockAsync())
{
while (true)
{
cancel.ThrowIfCancellationRequested();
try
{
// If no connection, wait then continue.
while (Nodes.ConnectedNodes.Count == 0)
{
await Task.Delay(100);
}
Node node = Nodes.ConnectedNodes.RandomElement();
if (node == default(Node))
{
await Task.Delay(100);
continue;
}
if (!node.IsConnected && !(IndexDownloader.Network != Network.RegTest))
{
await Task.Delay(100);
continue;
}
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 <WalletService>($"Disconnected node, because couldn't parse received block.");
node.DisconnectAsync("Couldn't parse block.");
continue;
}
if (!block.Check())
{
Logger.LogInfo <WalletService>($"Disconnected node, because block invalid block received.");
node.DisconnectAsync("Invalid block received.");
continue;
}
}
catch (TimeoutException)
{
Logger.LogInfo <WalletService>($"Disconnected node, because block download took too long.");
node.DisconnectAsync("Block download took too long.");
continue;
}
catch (OperationCanceledException)
{
Logger.LogInfo <WalletService>($"Disconnected node, because block download took too long.");
node.DisconnectAsync("Block download took too long.");
continue;
}
catch (Exception ex)
{
Logger.LogDebug <WalletService>(ex);
Logger.LogInfo <WalletService>($"Disconnected node, because block download failed: {ex.Message}");
node.DisconnectAsync("Block download failed.");
continue;
}
break; // If got this far break, then we have the block, it's valid. Break.
}
catch (Exception ex)
{
Logger.LogDebug <WalletService>(ex);
}
}
}
// Save the block
using (await BlockFolderLock.LockAsync())
{
var path = Path.Combine(BlocksFolderPath, hash.ToString());
await File.WriteAllBytesAsync(path, block.ToBytes());
}
return(block);
}
