void TryMaintainConnection(MqttClientConnection connection, DateTime now) { try { if (connection.Status != MqttClientConnectionStatus.Running) { // The connection is already dead or just created so there is no need to check it. return; } if (connection.ConnectPacket.KeepAlivePeriod == 0) { // The keep alive feature is not used by the current connection. return; } if (connection.IsReadingPacket) { // The connection is currently reading a (large) packet. So it is obviously // doing something and thus "connected". return; } // Values described here: [MQTT-3.1.2-24]. // If the client sends 5 sec. the server will allow up to 7.5 seconds. // If the client sends 1 sec. the server will allow up to 1.5 seconds. var maxDurationWithoutPacket = connection.ConnectPacket.KeepAlivePeriod * 1.5D; var secondsWithoutPackage = (now - connection.LastPacketReceivedTimestamp).TotalSeconds; if (secondsWithoutPackage < maxDurationWithoutPacket) { // A packet was received before the timeout is affected. return; } _logger.Warning(null, "Client '{0}': Did not receive any packet or keep alive signal.", connection.ClientId); // Execute the disconnection in background so that the keep alive monitor can continue // with checking other connections. // We do not need to wait for the task so no await is needed. // Also the internal state of the connection must be swapped to "Finalizing" because the // next iteration of the keep alive timer happens. var _ = connection.StopAsync(MqttDisconnectReasonCode.KeepAliveTimeout); } catch (Exception exception) { _logger.Error(exception, "Client {0}: Unhandled exception while checking keep alive timeouts.", connection.ClientId); } }
async Task <MqttApplicationMessageInterceptorContext> InterceptApplicationMessageAsync(IMqttServerApplicationMessageInterceptor interceptor, MqttClientConnection senderConnection, MqttApplicationMessage applicationMessage) { string senderClientId; IDictionary <object, object> sessionItems; var messageIsFromServer = senderConnection == null; if (messageIsFromServer) { senderClientId = _options.ClientId; sessionItems = _serverSessionItems; } else { senderClientId = senderConnection.ClientId; sessionItems = senderConnection.Session.Items; } var interceptorContext = new MqttApplicationMessageInterceptorContext(senderClientId, sessionItems, applicationMessage); await interceptor.InterceptApplicationMessagePublishAsync(interceptorContext).ConfigureAwait(false); return(interceptorContext); }
public void DispatchApplicationMessage(MqttApplicationMessage applicationMessage, MqttClientConnection sender) { if (applicationMessage == null) { throw new ArgumentNullException(nameof(applicationMessage)); } _messageQueue.Add(new MqttEnqueuedApplicationMessage(applicationMessage, sender)); }