public MqttClientConnection(MqttConnectPacket connectPacket,
IMqttChannelAdapter channelAdapter,
MqttClientSession session,
MqttConnectionValidatorContext connectionValidatorContext,
IMqttServerOptions serverOptions,
MqttClientSessionsManager sessionsManager,
IMqttRetainedMessagesManager retainedMessagesManager,
IMqttNetLogger logger)
{
Session = session ?? throw new ArgumentNullException(nameof(session));
_serverOptions = serverOptions ?? throw new ArgumentNullException(nameof(serverOptions));
_sessionsManager = sessionsManager ?? throw new ArgumentNullException(nameof(sessionsManager));
_retainedMessagesManager = retainedMessagesManager ?? throw new ArgumentNullException(nameof(retainedMessagesManager));
_channelAdapter = channelAdapter ?? throw new ArgumentNullException(nameof(channelAdapter));
_connectionValidatorContext = connectionValidatorContext ?? throw new ArgumentNullException(nameof(connectionValidatorContext));
_dataConverter = _channelAdapter.PacketFormatterAdapter.DataConverter;
_endpoint = _channelAdapter.Endpoint;
ConnectPacket = connectPacket ?? throw new ArgumentNullException(nameof(connectPacket));
if (logger == null)
{
throw new ArgumentNullException(nameof(logger));
}
_logger = logger.CreateScopedLogger(nameof(MqttClientConnection));
_connectedTimestamp = DateTime.UtcNow;
LastPacketReceivedTimestamp = _connectedTimestamp;
_lastNonKeepAlivePacketReceivedTimestamp = LastPacketReceivedTimestamp;
}
public MqttClientConnection(
MqttConnectPacket connectPacket,
IMqttChannelAdapter channelAdapter,
MqttClientSession session,
IMqttServerOptions serverOptions,
MqttClientSessionsManager sessionsManager,
MqttRetainedMessagesManager retainedMessagesManager,
IMqttNetChildLogger logger)
{
Session = session ?? throw new ArgumentNullException(nameof(session));
_serverOptions = serverOptions ?? throw new ArgumentNullException(nameof(serverOptions));
_sessionsManager = sessionsManager ?? throw new ArgumentNullException(nameof(sessionsManager));
_retainedMessagesManager = retainedMessagesManager ?? throw new ArgumentNullException(nameof(retainedMessagesManager));
_channelAdapter = channelAdapter ?? throw new ArgumentNullException(nameof(channelAdapter));
_dataConverter = _channelAdapter.PacketFormatterAdapter.DataConverter;
_endpoint = _channelAdapter.Endpoint;
_connectPacket = connectPacket ?? throw new ArgumentNullException(nameof(connectPacket));
if (logger == null)
{
throw new ArgumentNullException(nameof(logger));
}
_logger = logger.CreateChildLogger(nameof(MqttClientConnection));
_keepAliveMonitor = new MqttClientKeepAliveMonitor(_connectPacket.ClientId, StopAsync, _logger);
_connectedTimestamp = DateTime.UtcNow;
_lastPacketReceivedTimestamp = _connectedTimestamp;
_lastNonKeepAlivePacketReceivedTimestamp = _lastPacketReceivedTimestamp;
}
public MqttClientSubscriptionsManager(MqttClientSession clientSession, MqttServerEventDispatcher eventDispatcher, IMqttServerOptions serverOptions)
{
_clientSession = clientSession ?? throw new ArgumentNullException(nameof(clientSession));
// TODO: Consider removing the server options here and build a new class "ISubscriptionInterceptor" and just pass it. The instance is generated in the root server class upon start.
_serverOptions = serverOptions ?? throw new ArgumentNullException(nameof(serverOptions));
_eventDispatcher = eventDispatcher ?? throw new ArgumentNullException(nameof(eventDispatcher));
}
public void EnqueueApplicationMessage(MqttClientSession senderClientSession, MqttPublishPacket publishPacket)
{
if (publishPacket == null)
{
throw new ArgumentNullException(nameof(publishPacket));
}
_messageQueue.Add(new MqttEnqueuedApplicationMessage(senderClientSession, publishPacket), _cancellationToken);
}
public MqttClientPendingPacketsQueue(IMqttServerOptions options, MqttClientSession clientSession, IMqttNetChildLogger logger)
{
if (logger == null)
{
throw new ArgumentNullException(nameof(logger));
}
_options = options ?? throw new ArgumentNullException(nameof(options));
_clientSession = clientSession ?? throw new ArgumentNullException(nameof(clientSession));
_logger = logger.CreateChildLogger(nameof(MqttClientPendingPacketsQueue));
}
private async Task <GetOrCreateClientSessionResult> GetOrCreateClientSessionAsync(MqttConnectPacket connectPacket)
{
await _semaphore.WaitAsync().ConfigureAwait(false);
try
{
var isSessionPresent = _sessions.TryGetValue(connectPacket.ClientId, out var clientSession);
if (isSessionPresent)
{
if (connectPacket.CleanSession)
{
_sessions.Remove(connectPacket.ClientId);
await clientSession.StopAsync().ConfigureAwait(false);
clientSession.Dispose();
clientSession = null;
_logger.Trace <MqttClientSessionsManager>("Stopped existing session of client '{0}'.", connectPacket.ClientId);
}
else
{
_logger.Trace <MqttClientSessionsManager>("Reusing existing session of client '{0}'.", connectPacket.ClientId);
}
}
var isExistingSession = true;
if (clientSession == null)
{
isExistingSession = false;
clientSession = new MqttClientSession(connectPacket.ClientId, _options, _retainedMessagesManager, _logger)
{
ApplicationMessageReceivedCallback = DispatchApplicationMessageAsync
};
clientSession.SubscriptionsManager.TopicSubscribedCallback = ClientSubscribedTopicCallback;
clientSession.SubscriptionsManager.TopicUnsubscribedCallback = ClientUnsubscribedTopicCallback;
_sessions[connectPacket.ClientId] = clientSession;
_logger.Trace <MqttClientSessionsManager>("Created a new session for client '{0}'.", connectPacket.ClientId);
}
return(new GetOrCreateClientSessionResult {
IsExistingSession = isExistingSession, Session = clientSession
});
}
finally
{
_semaphore.Release();
}
}
private MqttApplicationMessage InterceptApplicationMessage(MqttClientSession senderClientSession, MqttApplicationMessage applicationMessage)
{
if (_options.ApplicationMessageInterceptor == null)
{
return(applicationMessage);
}
var interceptorContext = new MqttApplicationMessageInterceptorContext(
senderClientSession.ClientId,
applicationMessage);
_options.ApplicationMessageInterceptor(interceptorContext);
return(interceptorContext.ApplicationMessage);
}
private MqttApplicationMessageInterceptorContext InterceptApplicationMessage(MqttClientSession sender, MqttApplicationMessage applicationMessage)
{
var interceptor = _options.ApplicationMessageInterceptor;
if (interceptor == null)
{
return(null);
}
var interceptorContext = new MqttApplicationMessageInterceptorContext(sender?.ClientId, applicationMessage);
interceptor(interceptorContext);
return(interceptorContext);
}
public void EnqueueApplicationMessage(MqttClientSession senderClientSession, MqttPublishPacket publishPacket)
{
if (publishPacket == null)
{
throw new ArgumentNullException(nameof(publishPacket));
}
var checkSubscriptionsResult = _subscriptionsManager.CheckSubscriptions(publishPacket.Topic, publishPacket.QualityOfServiceLevel);
if (!checkSubscriptionsResult.IsSubscribed)
{
return;
}
publishPacket = new MqttPublishPacket
{
Topic = publishPacket.Topic,
Payload = publishPacket.Payload,
QualityOfServiceLevel = checkSubscriptionsResult.QualityOfServiceLevel,
Retain = false,
Dup = false
};
if (publishPacket.QualityOfServiceLevel > 0)
{
publishPacket.PacketIdentifier = _packetIdentifierProvider.GetNewPacketIdentifier();
}
if (_options.ClientMessageQueueInterceptor != null)
{
var context = new MqttClientMessageQueueInterceptorContext(
senderClientSession?.ClientId,
ClientId,
publishPacket.ToApplicationMessage());
_options.ClientMessageQueueInterceptor?.Invoke(context);
if (!context.AcceptEnqueue || context.ApplicationMessage == null)
{
return;
}
publishPacket.Topic = context.ApplicationMessage.Topic;
publishPacket.Payload = context.ApplicationMessage.Payload;
publishPacket.QualityOfServiceLevel = context.ApplicationMessage.QualityOfServiceLevel;
}
_pendingPacketsQueue.Enqueue(publishPacket);
}
private async Task <MqttClientConnection> CreateConnectionAsync(IMqttChannelAdapter channelAdapter, MqttConnectPacket connectPacket)
{
await _createConnectionGate.WaitAsync(_cancellationToken).ConfigureAwait(false);
try
{
var isSessionPresent = _sessions.TryGetValue(connectPacket.ClientId, out var session);
var isConnectionPresent = _connections.TryGetValue(connectPacket.ClientId, out var existingConnection);
if (isConnectionPresent)
{
await existingConnection.StopAsync().ConfigureAwait(false);
}
if (isSessionPresent)
{
if (connectPacket.CleanSession)
{
session = null;
_logger.Verbose("Deleting existing session of client '{0}'.", connectPacket.ClientId);
}
else
{
_logger.Verbose("Reusing existing session of client '{0}'.", connectPacket.ClientId);
}
}
if (session == null)
{
session = new MqttClientSession(connectPacket.ClientId, _eventDispatcher, _options, _logger);
_logger.Verbose("Created a new session for client '{0}'.", connectPacket.ClientId);
}
var connection = new MqttClientConnection(connectPacket, channelAdapter, session, _options, this, _retainedMessagesManager, _logger);
_connections[connection.ClientId] = connection;
_sessions[session.ClientId] = session;
return(connection);
}
finally
{
_createConnectionGate.Release();
}
}
public async Task DispatchApplicationMessageAsync(MqttClientSession senderClientSession, MqttApplicationMessage applicationMessage)
{
try
{
var interceptorContext = InterceptApplicationMessage(senderClientSession, applicationMessage);
if (interceptorContext.CloseConnection)
{
await senderClientSession.StopAsync().ConfigureAwait(false);
}
if (interceptorContext.ApplicationMessage == null || !interceptorContext.AcceptPublish)
{
return;
}
if (applicationMessage.Retain)
{
await _retainedMessagesManager.HandleMessageAsync(senderClientSession?.ClientId, applicationMessage).ConfigureAwait(false);
}
ApplicationMessageReceivedCallback?.Invoke(senderClientSession?.ClientId, applicationMessage);
}
catch (Exception exception)
{
_logger.Error <MqttClientSessionsManager>(exception, "Error while processing application message");
}
await _semaphore.WaitAsync().ConfigureAwait(false);
try
{
foreach (var clientSession in _sessions.Values)
{
await clientSession.EnqueueApplicationMessageAsync(applicationMessage);
}
}
finally
{
_semaphore.Release();
}
}
async Task <MqttClientConnection> CreateClientConnectionAsync(MqttConnectPacket connectPacket, MqttConnectionValidatorContext connectionValidatorContext, IMqttChannelAdapter channelAdapter, Func <Task> onStart, Func <MqttClientDisconnectType, Task> onStop)
{
using (await _createConnectionGate.WaitAsync(_cancellationToken).ConfigureAwait(false))
{
var isSessionPresent = _sessions.TryGetValue(connectPacket.ClientId, out var session);
var isConnectionPresent = _connections.TryGetValue(connectPacket.ClientId, out var existingConnection);
if (isConnectionPresent)
{
await existingConnection.StopAsync(true).ConfigureAwait(false);
}
if (isSessionPresent)
{
if (connectPacket.CleanSession)
{
session = null;
_logger.Verbose("Deleting existing session of client '{0}'.", connectPacket.ClientId);
}
else
{
_logger.Verbose("Reusing existing session of client '{0}'.", connectPacket.ClientId);
}
}
if (session == null)
{
session = new MqttClientSession(connectPacket.ClientId, connectionValidatorContext.SessionItems, _eventDispatcher, _options, _retainedMessagesManager, _logger);
_logger.Verbose("Created a new session for client '{0}'.", connectPacket.ClientId);
}
var connection = new MqttClientConnection(connectPacket, channelAdapter, session, _options, this, _retainedMessagesManager, onStart, onStop, _logger);
_connections[connection.ClientId] = connection;
_sessions[session.ClientId] = session;
return(connection);
}
}
private PrepareClientSessionResult PrepareClientSession(MqttConnectPacket connectPacket)
{
lock (_sessions)
{
var isSessionPresent = _sessions.TryGetValue(connectPacket.ClientId, out var clientSession);
if (isSessionPresent)
{
if (connectPacket.CleanSession)
{
_sessions.Remove(connectPacket.ClientId);
clientSession.Stop(MqttClientDisconnectType.Clean);
clientSession.Dispose();
clientSession = null;
_logger.Verbose("Stopped existing session of client '{0}'.", connectPacket.ClientId);
}
else
{
_logger.Verbose("Reusing existing session of client '{0}'.", connectPacket.ClientId);
}
}
var isExistingSession = true;
if (clientSession == null)
{
isExistingSession = false;
clientSession = new MqttClientSession(connectPacket.ClientId, _options, this, _retainedMessagesManager, _logger);
_sessions[connectPacket.ClientId] = clientSession;
_logger.Verbose("Created a new session for client '{0}'.", connectPacket.ClientId);
}
return(new PrepareClientSessionResult {
IsExistingSession = isExistingSession, Session = clientSession
});
}
}
public async Task DispatchApplicationMessageAsync(MqttClientSession senderClientSession, MqttApplicationMessage applicationMessage)
{
try
{
applicationMessage = InterceptApplicationMessage(senderClientSession, applicationMessage);
if (applicationMessage == null)
{
return;
}
if (applicationMessage.Retain)
{
await _retainedMessagesManager.HandleMessageAsync(senderClientSession?.ClientId, applicationMessage).ConfigureAwait(false);
}
_server.OnApplicationMessageReceived(senderClientSession?.ClientId, applicationMessage);
}
catch (Exception exception)
{
_logger.Error <MqttClientSessionsManager>(exception, "Error while processing application message");
}
await _semaphore.WaitAsync().ConfigureAwait(false);
try
{
foreach (var clientSession in _sessions.Values)
{
await clientSession.EnqueueApplicationMessageAsync(applicationMessage);
}
}
finally
{
_semaphore.Release();
}
}
public MqttClientSubscriptionsManager(MqttClientSession clientSession, MqttServerEventDispatcher eventDispatcher, IMqttServerOptions serverOptions)
{
_clientSession = clientSession ?? throw new ArgumentNullException(nameof(clientSession));
_options = serverOptions ?? throw new ArgumentNullException(nameof(serverOptions));
_eventDispatcher = eventDispatcher ?? throw new ArgumentNullException(nameof(eventDispatcher));
}
public MqttClientSessionStatus(MqttClientSessionsManager sessionsManager, MqttClientSession session)
{
_sessionsManager = sessionsManager;
_session = session;
}
public async Task RunSessionAsync(IMqttChannelAdapter clientAdapter, CancellationToken cancellationToken)
{
var clientId = string.Empty;
MqttClientSession clientSession = null;
try
{
if (!(await clientAdapter.ReceivePacketAsync(_options.DefaultCommunicationTimeout, cancellationToken).ConfigureAwait(false) is MqttConnectPacket connectPacket))
{
throw new MqttProtocolViolationException("The first packet from a client must be a 'CONNECT' packet [MQTT-3.1.0-1].");
}
clientId = connectPacket.ClientId;
// Switch to the required protocol version before sending any response.
clientAdapter.PacketSerializer.ProtocolVersion = connectPacket.ProtocolVersion;
var connectReturnCode = ValidateConnection(connectPacket);
if (connectReturnCode != MqttConnectReturnCode.ConnectionAccepted)
{
await clientAdapter.SendPacketsAsync(_options.DefaultCommunicationTimeout, cancellationToken, new MqttConnAckPacket
{
ConnectReturnCode = connectReturnCode
}).ConfigureAwait(false);
return;
}
var result = await GetOrCreateClientSessionAsync(connectPacket).ConfigureAwait(false);
clientSession = result.Session;
await clientAdapter.SendPacketsAsync(_options.DefaultCommunicationTimeout, cancellationToken, new MqttConnAckPacket
{
ConnectReturnCode = connectReturnCode,
IsSessionPresent = result.IsExistingSession
}).ConfigureAwait(false);
ClientConnectedCallback?.Invoke(new ConnectedMqttClient
{
ClientId = clientId,
ProtocolVersion = clientAdapter.PacketSerializer.ProtocolVersion
});
await clientSession.RunAsync(connectPacket, clientAdapter).ConfigureAwait(false);
}
catch (Exception exception)
{
_logger.Error <MqttClientSessionsManager>(exception, exception.Message);
}
finally
{
try
{
await clientAdapter.DisconnectAsync(_options.DefaultCommunicationTimeout).ConfigureAwait(false);
}
catch (Exception)
{
// ignored
}
ClientDisconnectedCallback?.Invoke(new ConnectedMqttClient
{
ClientId = clientId,
ProtocolVersion = clientAdapter.PacketSerializer.ProtocolVersion,
PendingApplicationMessages = clientSession?.PendingMessagesQueue.Count ?? 0
});
}
}
public MqttClientPendingMessagesQueue(IMqttServerOptions options, MqttClientSession clientSession, IMqttNetLogger logger)
{
_options = options ?? throw new ArgumentNullException(nameof(options));
_clientSession = clientSession ?? throw new ArgumentNullException(nameof(clientSession));
_logger = logger ?? throw new ArgumentNullException(nameof(logger));
}
MqttClientConnection CreateConnection(MqttConnectPacket connectPacket, IMqttChannelAdapter channelAdapter, MqttClientSession session, MqttConnectionValidatorContext connectionValidatorContext)
{
return(new MqttClientConnection(
connectPacket,
channelAdapter,
session,
connectionValidatorContext,
_options,
this,
_retainedMessagesManager,
_rootLogger));
}
public MqttEnqueuedApplicationMessage(MqttClientSession sender, MqttPublishPacket publishPacket)
{
Sender = sender;
PublishPacket = publishPacket;
}