/// <summary>
/// Loop thread that processes messages received from UDP receiver.
/// </summary>
/// <param name="data"></param>
private void UdpReceiverListenerThreadImpl(object data)
{
_threadStatus.IsThreadActive = true;
logger.Info("[" + _description + "-T] UdpReceiverListener active");
while (_threadStatus.IsThreadEnabled)
{
try
{
_threadStatus.ThreadHealthDate = DateTime.Now;
//check if there are any messages
if (_udpReceiver.CountMessagesInBuffer() > 0)
{
//dequeue message
NiawaNetDatagram message = _udpReceiver.GetNextMessageFromBuffer();
/*when receive UDP handshake, pass session data to TCP session manager*/
//check for handshake message
if (message.MessageType == MessageContent.HandshakeMessageContent.MESSAGE_CONTENT_TYPE)
{
//handshake message
MessageContent.HandshakeMessageContent remoteServerData = new MessageContent.HandshakeMessageContent(message.MessageContents);
logger.Info("[" + _description + "-T] Received handshake message from [" + remoteServerData.IpAddress + "]");
_evtRaiser.RaiseEvent("Session", "Received handshake message from [" + remoteServerData.IpAddress + "]", null, _threadStatus.NodeID, _threadStatus.ParentNodeID);
//find session
if (_tcpSessionManager.TcpSessions.ContainsKey(remoteServerData.IpAddress))
{
//we already have something relating to this session data
logger.Warn("[" + _description + "-T] UdpReceiverListener received a handshake message for existing session [" + remoteServerData.IpAddress + "]");
//check if any of the information has changed
TcpSession existingSession = _tcpSessionManager.TcpSessions[remoteServerData.IpAddress];
bool invalidateSession = false;
//check this existing session for any reasons that would invalidate the session
invalidateSession = ReceivedHandshakeExistingSessionValidations(existingSession, remoteServerData);
if (invalidateSession)
{
//invalidate session and create new one
logger.Info("[" + _description + "-T] UdpReceiverListener removing invalidated session before creating a new session for [" + remoteServerData.IpAddress + "]");
_evtRaiser.RaiseEvent("Session", "Removing invalidated session before creating a new session for [" + remoteServerData.IpAddress + "]", null, _threadStatus.NodeID, _threadStatus.ParentNodeID);
//remove old session
_tcpSessionManager.RemoveSession(remoteServerData.IpAddress, false);
//create a session with the remote session data, and then receive the session initialization from the remote
MessageContent.SessionInitMessageContent localSession = _tcpSessionManager.CreateNewSession(remoteServerData.IpAddress, remoteServerData.Hostname, remoteServerData.HandshakePort);
//transmit session initialization to the remote
_tcpSessionManager.TransmitSessionInitialization(remoteServerData.IpAddress, remoteServerData.HandshakePort, remoteServerData.Hostname, localSession);
}
else
{
//existing session is still valid; don't do anything
logger.Info("[" + _description + "-T] UdpReceiverListener ignoring handshake message for existing session [" + remoteServerData.IpAddress + "]");
_evtRaiser.RaiseEvent("Session", "Ignoring handshake message for existing session [" + remoteServerData.IpAddress + "]", null, _threadStatus.NodeID, _threadStatus.ParentNodeID);
}
}
else
{
/*we don't have anything relating to this sesion data yet*/
//create a session with the remote session data, and then receive the session initialization from the remote
MessageContent.SessionInitMessageContent localSession = _tcpSessionManager.CreateNewSession(remoteServerData.IpAddress, remoteServerData.Hostname, remoteServerData.HandshakePort);
//transmit session initialization to the remote
_tcpSessionManager.TransmitSessionInitialization(remoteServerData.IpAddress, remoteServerData.HandshakePort, remoteServerData.Hostname, localSession);
}
}
else if (message.MessageType == MessageContent.PingMessageContent.MESSAGE_CONTENT_TYPE_PING)
{
//ping message
MessageContent.PingMessageContent pingData = new MessageContent.PingMessageContent(message.MessageContents);
logger.Info("[" + _description + "-T] Received ping message from [" + pingData.IpAddress + "]");
_evtRaiser.RaiseEvent("Message", "Received ping message from [" + pingData.IpAddress + "]", null, _threadStatus.NodeID, _threadStatus.ParentNodeID);
//send a reply
TransmitPingMessage(true, message.SerialID.ToString());
}
else if (message.MessageType == MessageContent.PingMessageContent.MESSAGE_CONTENT_TYPE_PINGREPLY)
{
//ping message
MessageContent.PingMessageContent pingData = new MessageContent.PingMessageContent(message.MessageContents);
logger.Info("[" + _description + "-T] Received ping reply message from [" + pingData.IpAddress + "] for ping SerialID [" + pingData.ReplySerialID + "]");
_evtRaiser.RaiseEvent("Message", "Received ping reply from [" + pingData.IpAddress + "] for ping SerialID [" + pingData.ReplySerialID + "]", null, _threadStatus.NodeID, _threadStatus.ParentNodeID);
}
else
{
//message is not valid - not a handshake message
//throw away other data
logger.Warn("[" + _description + "-T] UdpReceiverListener ignoring unexpected message type [" + message.MessageType + "]");
_evtRaiser.RaiseEvent("Error", "UdpReceiverListener: Ignoring unexpected message type [" + message.MessageType + "]", null, _threadStatus.NodeID, _threadStatus.ParentNodeID);
}
}
else
{
//there are no messages
}
}
catch (System.Threading.ThreadAbortException) // ex1)
{
//thread was aborted
logger.Debug("[" + _description + "-T] Thread aborted");
break;
}
catch (System.Threading.ThreadInterruptedException) // ex1)
{
//thread was interrupted
logger.Debug("[" + _description + "-T] Thread interrupted");
break;
}
catch (Exception ex)
{
//exception
logger.Error("[" + _description + "-T] Error while listening to UdpReceiver: " + ex.Message + "]", ex);
//ipcLoggerMsg.Write("ReceiveMessageError", "[" + _logInstanceName + "]: " + "Error: " + ex.Message);
_evtRaiser.RaiseEvent("Error", "Error while listening to UdpReceiver [" + ex.Message + "]", null, _threadStatus.NodeID, _threadStatus.ParentNodeID);
_threadStatus.ErrorCount += 1;
System.Threading.Thread.Sleep(100);
}
System.Threading.Thread.Sleep(50);
}
//done working
_threadStatus.IsThreadActive = false;
}
/// <summary>
/// Transmits the UDP ping or ping reply message configured for this instance of NiawaAdHocNetworkAdapter.
/// </summary>
/// <param name="isReplyMessage">True if ping reply message; False if ping message</param>
public void TransmitPingMessage(bool isReplyMessage, string replySerialID)
{
try
{
if(!isReplyMessage )
{
logger.Info("[" + _description + "-M] Transmitting ping message");
//send message
_evtRaiser.RaiseEvent("Message", "Transmitting ping message", null, _threadStatus.NodeID, _threadStatus.ParentNodeID);
_threadStatus.MessageCount += 1;
/*broadcast UDP ping when requested by implementor*/
if (!_started) throw new Exception("[" + _description + "-M] Could not transmit ping message: NiawaAdHocNetworkAdapter is not started");
if (_tcpHandshakePort == 0) throw new Exception("[" + _description + "-M] Could not transmit ping message: HandshakePort [" + _tcpHandshakePort + "] is not valid.");
//create message
MessageContent.PingMessageContent pingMessage = new MessageContent.PingMessageContent(_ipAddress, _hostname, string.Empty);
NiawaNetDatagram message = new NiawaNetDatagram(_ipAddress, _udpPort, Guid.NewGuid(), _hostname, _applicationName, MessageContent.PingMessageContent.MESSAGE_CONTENT_TYPE_PING, pingMessage.ToJson());
//send message
_udpTransmitter.SendMessage(message);
}
else
{
logger.Info("[" + _description + "-M] Transmitting ping reply message");
//send message
_evtRaiser.RaiseEvent("Message", "Transmitting ping reply message", null, _threadStatus.NodeID, _threadStatus.ParentNodeID);
_threadStatus.MessageCount += 1;
/*broadcast UDP ping reply when requested by implementor*/
if (!_started) throw new Exception("[" + _description + "-M] Could not transmit ping reply message: NiawaAdHocNetworkAdapter is not started");
if (_tcpHandshakePort == 0) throw new Exception("[" + _description + "-M] Could not transmit ping reply message: HandshakePort [" + _tcpHandshakePort + "] is not valid.");
//create message
MessageContent.PingMessageContent pingMessage = new MessageContent.PingMessageContent(_ipAddress, _hostname, replySerialID);
NiawaNetDatagram message = new NiawaNetDatagram(_ipAddress, _udpPort, Guid.NewGuid(), _hostname, _applicationName, MessageContent.PingMessageContent.MESSAGE_CONTENT_TYPE_PINGREPLY, pingMessage.ToJson());
//send message
_udpTransmitter.SendMessage(message);
}
}
catch (Exception ex)
{
logger.Error("[" + _description + "-M] Error while transmitting ping/ping reply message: " + ex.Message, ex);
throw ex;
}
}
