Task <string> IMqttStorageProvider.StoreMessage(InFlightMessage message)
{
Guid messageId = Guid.NewGuid();
inFlight.Add(messageId, new SimpleInFlightMessage(message.Topic, message.Payload));
return(Util.RunSynchronously <string>(() => messageId.ToString()));
}
private List <InFlightMessage> ChooseMsg()
{
lock (_inFlight)
{
_inFlight.RemoveAll(m => IdIsLessThanEqualOther(m.Message.PacketId, _lastReceivedAck));
// If any were resent, then dont send anything new
if (_inFlight.Count > 0)
{
DateTime now = DateTime.Now;
if (_inFlight.Any(m => GetTimeBetween(m.LastSent, now) > InFlightTimeout))
{
List <InFlightMessage> toResend = _inFlight.ToList();
Log.WarnFormat("{0} - Resending {1} packets from #{2}", Endpoint, toResend.Count, toResend[0].Message.PacketId);
return(toResend);
}
}
if (_inFlight.Count >= MaxInFlight)
{
return(null);
}
lock (_messageQueue)
{
if (_messageQueue.Any())
{
// create new message, send it and track it
var msg = new InFlightMessage(_messageQueue.Dequeue().WithPacketId(NextPacketId), 0); // TODO - should this be able to perform an ack?
_inFlight.Add(msg);
return(new List <InFlightMessage> {
msg
});
}
}
OutboundMessage obMsg = CompileNextMessage();
if (obMsg == null)
{
return(null);
}
uint ackId = 0;
lock (_lastSentAckLock)
{
bool shouldSend = _readyToAck > _lastSentAck;
if (shouldSend)
{
ackId = _readyToAck;
}
}
var newMsg = new InFlightMessage(obMsg.WithPacketId(NextPacketId), ackId);
_inFlight.Add(newMsg);
return(new List <InFlightMessage> {
newMsg
});
}
}
private void SendMessage(Socket socket, InFlightMessage msg)
{
byte[] body = CompileMessage(msg);
msg.LastSent = DateTime.Now;
try
{
socket.SendTo(body, SocketFlags.None, Endpoint);
}
catch (ObjectDisposedException)
{
Log.ErrorFormat("{0} - Discarding message due to socket being disposed", Endpoint);
// Mark as timed out. This will cause it to be cleaned up shortly
_lastReceivedTime = DateTime.MinValue;
OnDisconnect?.Invoke(this);
}
}
private byte[] CompileMessage(InFlightMessage msg)
{
byte opcode = CompileOpcode(msg.Message.Type, msg.LastSent != DateTime.MinValue);
if (msg.AckId.HasValue)
{
opcode |= (byte)ReceivedPacket.CommandCodeFlags.AckReply;
}
byte len1 = (byte)((ReceivedPacket.HeaderLength + msg.Message.Payload.Length) / 256 | opcode << 3); // opcode 0x08 + length
byte len2 = (byte)((ReceivedPacket.HeaderLength + msg.Message.Payload.Length) % 256);
byte[] buffer =
{
len1, len2, // Opcode & Length
(byte)(SessionId >> 8), (byte)SessionId, // session id
0x00, 0x00, // ACKed Pkt Id
0x00, 0x00, // Unknown
0x00, 0x00, // unknown2
(byte)(msg.Message.PacketId / 256), (byte)(msg.Message.PacketId % 256), // pkt id
};
if (msg.AckId.HasValue || msg.Message.Type == OutboundMessage.OutboundMessageType.Ack)
{
var ackId = msg.AckId.GetValueOrDefault(0);
// set ack id
buffer[4] = (byte)(ackId / 256);
buffer[5] = (byte)(ackId % 256);
// clear pkt id
if (msg.Message.Type == OutboundMessage.OutboundMessageType.Ack)
{
buffer[10] = buffer[11] = 0x00;
}
}
// If no payload, dont append it
if (msg.Message.Payload.Length == 0)
{
return(buffer);
}
return(buffer.Concat(msg.Message.Payload).ToArray());
}
