public DistributedHost(
IWorkQueue workQueue,
ushort listenPort,
bool isListener = true,
int disconnectTimeout = -1,
INetLogger logger = null)
{
Contract.Requires(listenPort != 0);
ListenPort = listenPort;
this.workQueue = workQueue;
this.logger = logger;
// determine our IP
// hat tip https://stackoverflow.com/questions/6803073/get-local-ip-address
IPHostEntry host = Dns.GetHostEntry(Dns.GetHostName());
IPAddress ipv4Address = host
.AddressList
.FirstOrDefault(ip => ip.AddressFamily == AddressFamily.InterNetwork);
SocketAddress = new SerializedSocketAddress(new IPEndPoint(ipv4Address, listenPort).Serialize());
netManager = new NetManager(new Listener(this))
{
BroadcastReceiveEnabled = true,
UnconnectedMessagesEnabled = true
};
if (disconnectTimeout != -1)
{
netManager.DisconnectTimeout = disconnectTimeout;
}
netPacketProcessor = new NetPacketProcessor();
RegisterType <SerializedSocketAddress>();
RegisterType <DistributedId>();
netPacketProcessor.SubscribeReusable <AnnounceMessage, IPEndPoint>(OnAnnounceReceived);
netPacketProcessor.SubscribeReusable <AnnounceResponseMessage, IPEndPoint>(OnAnnounceResponseReceived);
netDataWriter = new NetDataWriter();
bool managerStarted;
if (isListener)
{
managerStarted = netManager.Start(ListenPort);
}
else
{
managerStarted = netManager.Start();
}
if (!managerStarted)
{
throw new PeerException("Could not start netManager");
}
}
/// <summary>
/// Get the proxies that are owned by this peer.
/// </summary>
public IReadOnlyDictionary <DistributedId, IDistributedObject> ProxiesForPeer(SerializedSocketAddress serializedSocketAddress)
{
Contract.Requires(netManager.ConnectedPeerList.Any(peer =>
{
SerializedSocketAddress peerAddress = new SerializedSocketAddress(peer);
bool addressesAreEqual = peerAddress.Equals(serializedSocketAddress);
return(addressesAreEqual);
}));
Contract.Requires(proxies.ContainsKey(serializedSocketAddress));
return(proxies[serializedSocketAddress]);
}
/// <summary>
/// Handle a disconnected peer by deleting all that peer's proxies' local objects, and dropping
/// all the proxies.
/// </summary>
public void OnPeerDisconnected(NetPeer netPeer, DisconnectInfo disconnectInfo)
{
SerializedSocketAddress peerAddress = new SerializedSocketAddress(netPeer);
if (Host.proxies.TryGetValue(peerAddress, out Dictionary <DistributedId, IDistributedObject> peerObjects))
{
// detach them all
foreach (IDistributedObject proxy in peerObjects.Values)
{
proxy.OnDetach();
}
// and drop the whole collection of proxies
Host.proxies.Remove(peerAddress);
}
}
/// <summary>
/// An announcement has been received (via broadcast); react accordingly.
/// </summary>
private void OnAnnounceReceived(AnnounceMessage message, IPEndPoint endpoint)
{
// heed only ipv4 for now... TBD what to do about this
if (endpoint.AddressFamily == AddressFamily.InterNetwork)
{
// is this actually our own announcement!?
SerializedSocketAddress incomingAddress = new SerializedSocketAddress(endpoint.Serialize());
if (incomingAddress == this.SocketAddress)
{
// ignore this, we're talking to ourselves
return;
}
PeerAnnounceCount++;
// do we know this peer already?
// (could happen in race scenario)
if (netManager.ConnectedPeerList.Any(peer => peer.EndPoint.Equals(endpoint)))
{
return;
}
// did we already respond to this peer?
if (AnnouncedEndPoints.Contains(endpoint))
{
return;
}
// did this peer know us already? (typical scenario given re-announcements)
if (message.KnownPeers.Contains(SocketAddress))
{
return;
}
logger?.WriteNet(NetLogLevel.Trace, $"DistributedHost.OnAnnounceReceived({endpoint}) -- responding. {ConnectionsStatusString()}]");
// send announce response
AnnounceResponseMessage response = new AnnounceResponseMessage {
};
SendUnconnectedMessage(response, endpoint);
}
}
private void OnDelete(NetPeer netPeer, DistributedId id, bool isRequest)
{
SerializedSocketAddress peerAddress = new SerializedSocketAddress(netPeer);
if (isRequest)
{
// owner id may or may not still exist; it's OK if it doesn't.
if (!owners.ContainsKey(id))
{
// do nothing; ignore the delete request altogether
}
else
{
// we will accept this request... for testing purposes.
// TBD if this is the right thing in general!
IDistributedObject distributedObject = owners[id];
// and tell all proxies
foreach (NetPeer proxyPeer in NetPeers)
{
distributedObject.DistributedType.SendDeleteMessageInternal(proxyPeer, false);
}
owners.Remove(id);
distributedObject.OnDelete();
}
}
else
{
// this is an authoritative delete message from the owner.
// we expect strong consistency here so the id should still exist.
Contract.Requires(proxies[peerAddress].ContainsKey(id));
IDistributedObject proxy = proxies[peerAddress][id];
proxies[peerAddress].Remove(id);
proxy.Delete();
}
}
/// <summary>
/// This is a new proxy being created on this peer, owned by netPeer.
/// </summary>
private void AddProxy(SerializedSocketAddress peerAddress, IDistributedObject proxy)
{
Contract.Requires(!proxy.IsOwner);
proxies[peerAddress].Add(proxy.Id, proxy);
}
