public NodesGroup(
Network network,
NodeConnectionParameters connectionParameters = null,
NodeRequirement requirements = null)
{
AllowSameGroup = false;
MaximumNodeConnection = 8;
_Network = network;
cs = new object();
_ConnectedNodes = new NodesCollection();
_ConnectionParameters = connectionParameters ?? new NodeConnectionParameters();
_ConnectionParameters = _ConnectionParameters.Clone();
_Requirements = requirements ?? new NodeRequirement();
_Disconnect = new CancellationTokenSource();
}
/// <summary>
/// Try to connect to a single endpoint
/// The connected endpoint will be added to the nodes collection
/// </summary>
/// <param name="force">Connect even if MaximumNodeConnection limit was reached</param>
/// <returns>A connected node or null</returns>
public Node TryConnectNode(IPEndPoint endPoint, bool force = false)
{
// this is not expected to be performance critical so
// only use a single lock. placing a lock before the
// check should avoid connecting to a node already connected
lock (tcs)
{
// first look for the node maybe its already connected
var node = this.ConnectedNodes.FindByEndpoint(endPoint);
if (node != null)
{
return(node);
}
if (!force && _ConnectedNodes.Count >= MaximumNodeConnection)
{
return(null);
}
var scope = _Trace.Open();
NodeServerTrace.Information("Connected nodes : " + _ConnectedNodes.Count + "/" + MaximumNodeConnection);
var parameters = _ConnectionParameters.Clone();
parameters.TemplateBehaviors.Add(new NodesGroupBehavior(this));
parameters.ConnectCancellation = _Disconnect.Token;
try
{
node = Node.Connect(_Network, endPoint, parameters);
var timeout = CancellationTokenSource.CreateLinkedTokenSource(_Disconnect.Token);
timeout.CancelAfter(5000);
node.VersionHandshake(_Requirements, timeout.Token);
NodeServerTrace.Information("Node successfully connected to and handshaked");
}
catch (OperationCanceledException ex)
{
if (_Disconnect.Token.IsCancellationRequested)
{
throw;
}
NodeServerTrace.Error("Timeout for picked node", ex);
if (node != null)
{
node.DisconnectAsync("Handshake timeout", ex);
}
}
catch (SocketException)
{
_ConnectionParameters.ConnectCancellation.WaitHandle.WaitOne(500);
}
catch (Exception ex)
{
NodeServerTrace.Error("Error while connecting to node", ex);
if (node != null)
{
node.DisconnectAsync("Error while connecting", ex);
}
}
finally
{
scope?.Dispose();
}
return(node);
}
}
internal void DiscoverPeers(Network network, NodeConnectionParameters parameters)
{
int peerToFind = 1000;
TraceCorrelation traceCorrelation = new TraceCorrelation(NodeServerTrace.Trace, "Discovering nodes");
int found = 0;
using (traceCorrelation.Open())
{
while (found < peerToFind)
{
parameters.ConnectCancellation.ThrowIfCancellationRequested();
NodeServerTrace.PeerTableRemainingPeerToGet(-found + peerToFind);
List <NetworkAddress> peers = new List <NetworkAddress>();
peers.AddRange(this.GetAddr());
if (peers.Count == 0)
{
PopulateTableWithDNSNodes(network, peers);
PopulateTableWithHardNodes(network, peers);
peers = new List <NetworkAddress>(peers.OrderBy(a => RandomUtils.GetInt32()));
}
CancellationTokenSource peerTableFull = new CancellationTokenSource();
CancellationToken loopCancel = CancellationTokenSource.CreateLinkedTokenSource(peerTableFull.Token, parameters.ConnectCancellation).Token;
try
{
Parallel.ForEach(peers, new ParallelOptions()
{
MaxDegreeOfParallelism = 5,
CancellationToken = loopCancel,
}, p =>
{
CancellationTokenSource timeout = new CancellationTokenSource(TimeSpan.FromSeconds(5));
var cancelConnection = CancellationTokenSource.CreateLinkedTokenSource(timeout.Token, loopCancel);
Node n = null;
try
{
var param2 = parameters.Clone();
param2.ConnectCancellation = cancelConnection.Token;
var addrman = param2.TemplateBehaviors.Find <AddressManagerBehavior>();
param2.TemplateBehaviors.Clear();
param2.TemplateBehaviors.Add(addrman);
n = Node.Connect(network, p.Endpoint, param2);
n.VersionHandshake(cancelConnection.Token);
n.MessageReceived += (s, a) =>
{
var addr = (a.Message.Payload as AddrPayload);
if (addr != null)
{
Interlocked.Add(ref found, addr.Addresses.Length);
if (found >= peerToFind)
{
peerTableFull.Cancel();
}
}
};
n.SendMessageAsync(new GetAddrPayload());
loopCancel.WaitHandle.WaitOne(2000);
}
catch
{
}
finally
{
if (n != null)
{
n.DisconnectAsync();
}
}
if (found >= peerToFind)
{
peerTableFull.Cancel();
}
else
{
NodeServerTrace.Information("Need " + (-found + peerToFind) + " more peers");
}
});
}
catch (OperationCanceledException)
{
if (parameters.ConnectCancellation.IsCancellationRequested)
{
throw;
}
}
}
}
}
internal void StartConnecting()
{
if (_Disconnect.IsCancellationRequested)
{
return;
}
if (_ConnectedNodes.Count >= MaximumNodeConnection)
{
return;
}
if (_Connecting)
{
return;
}
Task.Factory.StartNew(() =>
{
if (Monitor.TryEnter(cs))
{
_Connecting = true;
TraceCorrelationScope scope = null;
try
{
while (!_Disconnect.IsCancellationRequested && _ConnectedNodes.Count < MaximumNodeConnection)
{
scope = scope ?? _Trace.Open();
NodeServerTrace.Information("Connected nodes : " + _ConnectedNodes.Count + "/" + MaximumNodeConnection);
var parameters = _ConnectionParameters.Clone();
parameters.TemplateBehaviors.Add(new NodesGroupBehavior(this));
parameters.ConnectCancellation = _Disconnect.Token;
var addrman = AddressManagerBehavior.GetAddrman(parameters);
if (addrman == null)
{
addrman = _DefaultAddressManager;
AddressManagerBehavior.SetAddrman(parameters, addrman);
}
Node node = null;
try
{
node = Node.Connect(_Network, parameters, AllowSameGroup ? null : _ConnectedNodes.Select(n => n.RemoteSocketAddress).ToArray());
var timeout = CancellationTokenSource.CreateLinkedTokenSource(_Disconnect.Token);
timeout.CancelAfter(5000);
node.VersionHandshake(_Requirements, timeout.Token);
NodeServerTrace.Information("Node successfully connected to and handshaked");
}
catch (OperationCanceledException ex)
{
if (_Disconnect.Token.IsCancellationRequested)
{
throw;
}
NodeServerTrace.Error("Timeout for picked node", ex);
if (node != null)
{
node.DisconnectAsync("Handshake timeout", ex);
}
}
catch (Exception ex)
{
NodeServerTrace.Error("Error while connecting to node", ex);
if (node != null)
{
node.DisconnectAsync("Error while connecting", ex);
}
}
}
}
finally
{
Monitor.Exit(cs);
_Connecting = false;
if (scope != null)
{
scope.Dispose();
}
}
}
}, TaskCreationOptions.LongRunning);
}