private async Task ReceivePackets(CancellationToken cancellationToken)
{
MqttTrace.Information(nameof(MqttClient), "Start receiving packets.");
try
{
while (!cancellationToken.IsCancellationRequested)
{
var mqttPacket = await _adapter.ReceivePacketAsync(TimeSpan.Zero);
MqttTrace.Information(nameof(MqttClient), $"Received <<< {mqttPacket}");
#pragma warning disable CS4014 // Because this call is not awaited, execution of the current method continues before the call is completed
Task.Run(() => ProcessReceivedPacketAsync(mqttPacket), cancellationToken);
#pragma warning restore CS4014 // Because this call is not awaited, execution of the current method continues before the call is completed
}
}
catch (MqttCommunicationException exception)
{
MqttTrace.Warning(nameof(MqttClient), exception, "MQTT communication error while receiving packets.");
}
catch (Exception exception)
{
MqttTrace.Error(nameof(MqttClient), exception, "Error while receiving packets.");
}
finally
{
MqttTrace.Information(nameof(MqttClient), "Stopped receiving packets.");
await DisconnectInternalAsync();
}
}
private async Task ReceivePackets(CancellationToken cancellationToken)
{
MqttTrace.Information(nameof(MqttClient), "Start receiving packets.");
try
{
while (!cancellationToken.IsCancellationRequested)
{
var mqttPacket = await _adapter.ReceivePacketAsync(TimeSpan.Zero);
MqttTrace.Information(nameof(MqttClient), $"Received <<< {mqttPacket}");
Task.Run(() => ProcessReceivedPacket(mqttPacket), cancellationToken).Forget();
}
}
catch (MqttCommunicationException exception)
{
MqttTrace.Warning(nameof(MqttClient), exception, "MQTT communication error while receiving packets.");
}
catch (Exception exception)
{
MqttTrace.Error(nameof(MqttClient), exception, "Error while receiving packets.");
}
finally
{
MqttTrace.Information(nameof(MqttClient), "Stopped receiving packets.");
await DisconnectInternalAsync();
}
}
private async Task ReceivePacketsAsync(CancellationToken cancellationToken)
{
_logger.LogInformation("Start receiving packets.");
try
{
while (!cancellationToken.IsCancellationRequested)
{
_isReceivingPackets = true;
var packet = await _adapter.ReceivePacketAsync(TimeSpan.Zero, cancellationToken).ConfigureAwait(false);
if (cancellationToken.IsCancellationRequested)
{
return;
}
StartProcessReceivedPacket(packet, cancellationToken);
}
}
catch (OperationCanceledException)
{
if (cancellationToken.IsCancellationRequested)
{
return;
}
await DisconnectInternalAsync().ConfigureAwait(false);
}
catch (MqttCommunicationException exception)
{
if (cancellationToken.IsCancellationRequested)
{
return;
}
_logger.LogWarning(new EventId(), exception, "MQTT communication exception while receiving packets.");
await DisconnectInternalAsync().ConfigureAwait(false);
}
catch (Exception exception)
{
_logger.LogError(new EventId(), exception, "Unhandled exception while receiving packets.");
await DisconnectInternalAsync().ConfigureAwait(false);
}
finally
{
_logger.LogInformation(nameof(MqttClient), "Stopped receiving packets.");
}
}
public async Task RunAsync(string identifier, MqttApplicationMessage willApplicationMessage, IMqttCommunicationAdapter adapter)
{
if (adapter == null)
{
throw new ArgumentNullException(nameof(adapter));
}
_willApplicationMessage = willApplicationMessage;
try
{
_identifier = identifier;
Adapter = adapter;
_cancellationTokenSource = new CancellationTokenSource();
_messageQueue.Start(adapter);
while (!_cancellationTokenSource.IsCancellationRequested)
{
var packet = await adapter.ReceivePacketAsync(TimeSpan.Zero, _cancellationTokenSource.Token).ConfigureAwait(false);
await HandleIncomingPacketAsync(packet).ConfigureAwait(false);
}
}
catch (MqttCommunicationException)
{
}
catch (Exception exception)
{
MqttTrace.Error(nameof(MqttClientSession), exception, "Client '{0}': Unhandled exception while processing client packets.", _identifier);
}
finally
{
if (willApplicationMessage != null)
{
_publishPacketReceivedCallback(this, _willApplicationMessage.ToPublishPacket());
}
_messageQueue.Stop();
_cancellationTokenSource.Cancel();
Adapter = null;
MqttTrace.Information(nameof(MqttClientSession), "Client '{0}': Disconnected.", _identifier);
}
}
private async Task ReceivePackets(CancellationToken cancellationToken)
{
MqttTrace.Information(nameof(MqttClient), "Start receiving packets.");
try
{
while (!cancellationToken.IsCancellationRequested)
{
var packet = await _adapter.ReceivePacketAsync(TimeSpan.Zero, cancellationToken).ConfigureAwait(false);
if (cancellationToken.IsCancellationRequested)
{
return;
}
StartProcessReceivedPacket(packet, cancellationToken);
}
}
catch (TaskCanceledException)
{
}
catch (MqttCommunicationException exception)
{
if (cancellationToken.IsCancellationRequested)
{
return;
}
MqttTrace.Warning(nameof(MqttClient), exception, "MQTT communication exception while receiving packets.");
await DisconnectInternalAsync().ConfigureAwait(false);
}
catch (Exception exception)
{
MqttTrace.Error(nameof(MqttClient), exception, "Unhandled exception while receiving packets.");
await DisconnectInternalAsync().ConfigureAwait(false);
}
finally
{
MqttTrace.Information(nameof(MqttClient), "Stopped receiving packets.");
}
}
private async Task ReceivePacketsAsync(IMqttCommunicationAdapter adapter, CancellationToken cancellationToken)
{
try
{
while (!cancellationToken.IsCancellationRequested)
{
var packet = await adapter.ReceivePacketAsync(TimeSpan.Zero, cancellationToken).ConfigureAwait(false);
await ProcessReceivedPacketAsync(adapter, packet, cancellationToken).ConfigureAwait(false);
}
}
catch (OperationCanceledException)
{
}
catch (MqttCommunicationException exception)
{
_logger.LogWarning(new EventId(), exception, "Client '{0}': Communication exception while processing client packets.", ClientId);
await StopAsync();
}
catch (Exception exception)
{
_logger.LogError(new EventId(), exception, "Client '{0}': Unhandled exception while processing client packets.", ClientId);
await StopAsync();
}
}
public async Task RunClientSessionAsync(IMqttCommunicationAdapter clientAdapter, CancellationToken cancellationToken)
{
var clientId = string.Empty;
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 clientSession = await GetOrCreateClientSessionAsync(connectPacket);
await clientAdapter.SendPacketsAsync(_options.DefaultCommunicationTimeout, cancellationToken, new MqttConnAckPacket
{
ConnectReturnCode = connectReturnCode,
IsSessionPresent = clientSession.IsExistingSession
}).ConfigureAwait(false);
ClientConnected?.Invoke(this, new MqttClientConnectedEventArgs(new ConnectedMqttClient
{
ClientId = clientId,
ProtocolVersion = clientAdapter.PacketSerializer.ProtocolVersion
}));
using (_logger.BeginScope(clientId))
{
await clientSession.Session.RunAsync(connectPacket.WillMessage, clientAdapter).ConfigureAwait(false);
}
}
catch (Exception exception)
{
_logger.LogError(new EventId(), exception, exception.Message);
}
finally
{
try
{
await clientAdapter.DisconnectAsync(_options.DefaultCommunicationTimeout).ConfigureAwait(false);
}
catch (Exception)
{
// ignored
}
ClientDisconnected?.Invoke(this, new MqttClientDisconnectedEventArgs(new ConnectedMqttClient
{
ClientId = clientId,
ProtocolVersion = clientAdapter.PacketSerializer.ProtocolVersion
}));
}
}