public void ReceivedHeartBeat(Address sender, TCPHearBeat hrtBeat)
{
Message rspMsg;
switch (hrtBeat.Type)
{
case TCPHearBeat.HEART_BEAT:
if (_enclosingInstance.Stack.NCacheLog.IsInfoEnabled)
{
_enclosingInstance.Stack.NCacheLog.Info("ConnectionKeepAlive.ReceivedHeartBeat", "received heartbeat from ->:" + sender.ToString());
}
lock (_idleConnections.SyncRoot)
{
_idleConnections.Remove(sender);
}
break;
case TCPHearBeat.SEND_HEART_BEAT:
rspMsg = new Message(sender, null, new byte[0]);
rspMsg.putHeader(HeaderType.KEEP_ALIVE, new TCPHearBeat(TCPHearBeat.HEART_BEAT));
if (_enclosingInstance.Stack.NCacheLog.IsInfoEnabled)
{
_enclosingInstance.Stack.NCacheLog.Info("ConnectionKeepAlive.ReceivedHeartBeat", "seding heartbeat to ->:" + sender.ToString());
}
_enclosingInstance.sendUnicastMessage(rspMsg, false, rspMsg.Payload, Priority.High);
break;
case TCPHearBeat.ARE_YOU_ALIVE:
rspMsg = new Message(sender, null, new byte[0]);
TCPHearBeat rsphrtBeat = (_enclosingInstance.isClosing || _enclosingInstance._leaving) ? new TCPHearBeat(TCPHearBeat.I_AM_LEAVING) : new TCPHearBeat(TCPHearBeat.I_AM_NOT_DEAD);
rsphrtBeat = _enclosingInstance.isStarting ? new TCPHearBeat(TCPHearBeat.I_AM_STARTING) : rsphrtBeat;
rspMsg.putHeader(HeaderType.KEEP_ALIVE, rsphrtBeat);
if (_enclosingInstance.Stack.NCacheLog.IsInfoEnabled)
{
_enclosingInstance.Stack.NCacheLog.Info("ConnectionKeepAlive.ReceivedHeartBeat", "seding status" + rsphrtBeat + " to ->:" + sender.ToString());
}
_enclosingInstance.sendUnicastMessage(rspMsg, false, rspMsg.Payload, Priority.High);
break;
case TCPHearBeat.I_AM_STARTING:
case TCPHearBeat.I_AM_LEAVING:
case TCPHearBeat.I_AM_NOT_DEAD:
lock (_status_mutex)
{
if (_currentSuspect != null && _currentSuspect.Equals(sender))
{
_statusReceived = hrtBeat;
Monitor.Pulse(_status_mutex);
}
}
break;
}
}
/// <summary>
/// Checks the status of a node whether he is running or not. We send a status request
/// message and wait for the response for a particular timeout. If the node is alive
/// it sends backs its status otherwise timeout occurs and we consider hime DEAD.
/// </summary>
private void CheckStatus()
{
while (_statusCheckingThread != null)
{
lock (_checkStatusList.SyncRoot)
{
if (_checkStatusList.Count > 0)
{
_currentSuspect = _checkStatusList[0] as Address;
_checkStatusList.Remove(_currentSuspect);
}
else
{
_currentSuspect = null;
}
if (_currentSuspect == null)
{
_statusCheckingThread = null;
continue;
}
}
lock (_status_mutex)
{
try
{
NodeStatus nodeStatus = null;
if (_enclosingInstance.ct.ConnectionExist(_currentSuspect))
{
Message msg = new Message(_currentSuspect, null, new byte[0]);
msg.putHeader(HeaderType.KEEP_ALIVE, new TCPHearBeat(TCPHearBeat.ARE_YOU_ALIVE));
if (_enclosingInstance.Stack.NCacheLog.IsInfoEnabled)
{
_enclosingInstance.Stack.NCacheLog.Info("ConnectionKeepAlive.CheckStatus", "sending status request to " + _currentSuspect);
}
_enclosingInstance.sendUnicastMessage(msg, false, msg.Payload, Priority.High);
_statusReceived = null;
//wait for the result or timeout occurs first;
Monitor.Wait(_status_mutex, _statusTimeout);
if (_statusReceived != null)
{
TCPHearBeat status = _statusReceived as TCPHearBeat;
if (_enclosingInstance.Stack.NCacheLog.IsInfoEnabled)
{
_enclosingInstance.Stack.NCacheLog.Info("ConnectionKeepAlive.CheckStatus", "received status " + status + " from " + _currentSuspect);
}
if (status.Type == TCPHearBeat.I_AM_NOT_DEAD)
{
nodeStatus = new NodeStatus(_currentSuspect, NodeStatus.IS_ALIVE);
}
else if (status.Type == TCPHearBeat.I_AM_LEAVING)
{
nodeStatus = new NodeStatus(_currentSuspect, NodeStatus.IS_LEAVING);
}
else if (status.Type == TCPHearBeat.I_AM_STARTING)
{
nodeStatus = new NodeStatus(_currentSuspect, NodeStatus.IS_DEAD);
}
}
else
{
nodeStatus = new NodeStatus(_currentSuspect, NodeStatus.IS_DEAD);
if (_enclosingInstance.Stack.NCacheLog.IsInfoEnabled)
{
_enclosingInstance.Stack.NCacheLog.Info("ConnectionKeepAlive.CheckStatus", "did not receive status from " + _currentSuspect + "; consider him DEAD");
}
}
}
else
{
if (_enclosingInstance.Stack.NCacheLog.IsInfoEnabled)
{
_enclosingInstance.Stack.NCacheLog.Info("ConnectionKeepAlive.CheckStatus", "no connection exists for " + _currentSuspect);
}
nodeStatus = new NodeStatus(_currentSuspect, NodeStatus.IS_DEAD);
}
Event statusEvent = new Event(Event.GET_NODE_STATUS_OK, nodeStatus);
_enclosingInstance.passUp(statusEvent);
}
catch (Exception e)
{
_enclosingInstance.Stack.NCacheLog.Error("ConnectionKeepAlive.CheckStatus", e.ToString());
}
finally
{
_currentSuspect = null;
_statusReceived = null;
}
}
}
}
