async Task TryReceivePacketsAsync(CancellationToken cancellationToken)
{
try
{
_logger.Verbose("Start receiving packets.");
while (!cancellationToken.IsCancellationRequested)
{
var packet = await _adapter.ReceivePacketAsync(TimeSpan.Zero, cancellationToken).ConfigureAwait(false);
if (cancellationToken.IsCancellationRequested)
{
return;
}
if (packet == null)
{
if (!DisconnectIsPending())
{
await DisconnectInternalAsync(_packetReceiverTask, null, null).ConfigureAwait(false);
}
return;
}
await TryProcessReceivedPacketAsync(packet, cancellationToken).ConfigureAwait(false);
}
}
catch (Exception exception)
{
if (_cleanDisconnectInitiated)
{
return;
}
if (exception is OperationCanceledException)
{
}
else if (exception is MqttCommunicationException)
{
_logger.Warning(exception, "Communication error while receiving packets.");
}
else
{
_logger.Error(exception, "Error while receiving packets.");
}
_packetDispatcher.Dispatch(exception);
if (!DisconnectIsPending())
{
await DisconnectInternalAsync(_packetReceiverTask, exception, null).ConfigureAwait(false);
}
}
finally
{
_logger.Verbose("Stopped receiving packets.");
}
}
private async Task ReceivePacketsAsync(CancellationToken cancellationToken)
{
_logger.Verbose("Start receiving packets.");
try
{
while (!cancellationToken.IsCancellationRequested)
{
var packet = await _adapter.ReceivePacketAsync(TimeSpan.Zero, cancellationToken).ConfigureAwait(false);
if (packet != null)
{
await ProcessReceivedPacketAsync(packet, cancellationToken).ConfigureAwait(false);
}
}
}
catch (Exception exception)
{
if (_cleanDisconnectInitiated)
{
return;
}
if (exception is OperationCanceledException)
{
_logger.Verbose("MQTT OperationCanceled exception while receiving packets.");
}
else if (exception is MqttCommunicationException)
{
_logger.Warning(exception, "MQTT communication exception while receiving packets.");
}
else
{
_logger.Error(exception, "Unhandled exception while receiving packets.");
}
_packetDispatcher.Dispatch(exception);
if (_disconnectReason.TrySetException(exception))
{
await DisconnectInternalAsync(_packetReceiverTask, exception).ConfigureAwait(false);
}
}
finally
{
_logger.Verbose("Stopped receiving packets.");
}
}
private async Task ProcessReceivedPacketAsync(MqttBasePacket packet)
{
try
{
_logger.Info <MqttClient>("Received <<< {0}", packet);
if (packet is MqttPublishPacket publishPacket)
{
await ProcessReceivedPublishPacketAsync(publishPacket).ConfigureAwait(false);
return;
}
if (packet is MqttPingReqPacket)
{
await SendAsync(new MqttPingRespPacket()).ConfigureAwait(false);
return;
}
if (packet is MqttDisconnectPacket)
{
await DisconnectAsync().ConfigureAwait(false);
return;
}
if (packet is MqttPubRelPacket pubRelPacket)
{
await ProcessReceivedPubRelPacket(pubRelPacket).ConfigureAwait(false);
return;
}
_packetDispatcher.Dispatch(packet);
}
catch (Exception exception)
{
_logger.Error <MqttClient>(exception, "Unhandled exception while processing received packet.");
}
}