private byte Serialize(MqttConnectPacket packet, MqttPacketWriter writer)
{
ValidateConnectPacket(packet);
// Write variable header
writer.Write(0x00, 0x04); // 3.1.2.1 Protocol Name
if (ProtocolVersion == MqttProtocolVersion.V311)
{
writer.Write(ProtocolVersionV311Name);
writer.Write(0x04); // 3.1.2.2 Protocol Level (4)
}
else
{
writer.Write(ProtocolVersionV310Name);
writer.Write(0x64, 0x70, 0x03); // Protocol Level (0x03)
}
var connectFlags = new ByteWriter(); // 3.1.2.3 Connect Flags
connectFlags.Write(false); // Reserved
connectFlags.Write(packet.CleanSession);
connectFlags.Write(packet.WillMessage != null);
if (packet.WillMessage != null)
{
connectFlags.Write((int)packet.WillMessage.QualityOfServiceLevel, 2);
connectFlags.Write(packet.WillMessage.Retain);
}
else
{
connectFlags.Write(0, 2);
connectFlags.Write(false);
}
connectFlags.Write(packet.Password != null);
connectFlags.Write(packet.Username != null);
writer.Write(connectFlags);
writer.Write(packet.KeepAlivePeriod);
writer.WriteWithLengthPrefix(packet.ClientId);
if (packet.WillMessage != null)
{
writer.WriteWithLengthPrefix(packet.WillMessage.Topic);
writer.WriteWithLengthPrefix(packet.WillMessage.Payload);
}
if (packet.Username != null)
{
writer.WriteWithLengthPrefix(packet.Username);
}
if (packet.Password != null)
{
writer.WriteWithLengthPrefix(packet.Password);
}
return(MqttPacketWriter.BuildFixedHeader(MqttControlPacketType.Connect));
}
private static byte Serialize(MqttSubAckPacket packet, MqttPacketWriter writer)
{
writer.Write(packet.PacketIdentifier);
if (packet.SubscribeReturnCodes?.Any() == true)
{
foreach (var packetSubscribeReturnCode in packet.SubscribeReturnCodes)
{
writer.Write((byte)packetSubscribeReturnCode);
}
}
return(MqttPacketWriter.BuildFixedHeader(MqttControlPacketType.SubAck));
}
private byte Serialize(MqttConnAckPacket packet, MqttPacketWriter writer)
{
var connectAcknowledgeFlags = new ByteWriter();
if (ProtocolVersion == MqttProtocolVersion.V311)
{
connectAcknowledgeFlags.Write(packet.IsSessionPresent);
}
writer.Write(connectAcknowledgeFlags);
writer.Write((byte)packet.ConnectReturnCode);
return(MqttPacketWriter.BuildFixedHeader(MqttControlPacketType.ConnAck));
}
private static byte Serialize(MqttUnsubscribePacket packet, MqttPacketWriter writer)
{
if (!packet.TopicFilters.Any())
{
throw new MqttProtocolViolationException("At least one topic filter must be set [MQTT-3.10.3-2].");
}
writer.Write(packet.PacketIdentifier);
if (packet.TopicFilters?.Any() == true)
{
foreach (var topicFilter in packet.TopicFilters)
{
writer.WriteWithLengthPrefix(topicFilter);
}
}
return(MqttPacketWriter.BuildFixedHeader(MqttControlPacketType.Unsubscibe, 0x02));
}
private static byte Serialize(MqttSubscribePacket packet, MqttPacketWriter writer)
{
if (!packet.TopicFilters.Any())
{
throw new MqttProtocolViolationException("At least one topic filter must be set [MQTT-3.8.3-3].");
}
writer.Write(packet.PacketIdentifier);
if (packet.TopicFilters?.Count > 0)
{
foreach (var topicFilter in packet.TopicFilters)
{
writer.WriteWithLengthPrefix(topicFilter.Topic);
writer.Write((byte)topicFilter.QualityOfServiceLevel);
}
}
return(MqttPacketWriter.BuildFixedHeader(MqttControlPacketType.Subscribe, 0x02));
}
private static byte Serialize(MqttPublishPacket packet, MqttPacketWriter writer)
{
ValidatePublishPacket(packet);
writer.WriteWithLengthPrefix(packet.Topic);
if (packet.QualityOfServiceLevel > MqttQualityOfServiceLevel.AtMostOnce)
{
writer.Write(packet.PacketIdentifier);
}
else
{
if (packet.PacketIdentifier > 0)
{
throw new MqttProtocolViolationException("Packet identifier must be empty if QoS == 0 [MQTT-2.3.1-5].");
}
}
if (packet.Payload?.Length > 0)
{
writer.Write(packet.Payload);
}
byte fixedHeader = 0;
if (packet.Retain)
{
fixedHeader |= 0x01;
}
fixedHeader |= (byte)((byte)packet.QualityOfServiceLevel << 1);
if (packet.Dup)
{
fixedHeader |= 0x08;
}
return(MqttPacketWriter.BuildFixedHeader(MqttControlPacketType.Publish, fixedHeader));
}
private static byte SerializeEmptyPacket(MqttControlPacketType type)
{
return(MqttPacketWriter.BuildFixedHeader(type));
}
private static byte Serialize(IMqttPacketWithIdentifier packet, BinaryWriter writer)
{
writer.Write(packet.PacketIdentifier);
return(MqttPacketWriter.BuildFixedHeader(MqttControlPacketType.UnsubAck));
}
private static byte Serialize(MqttPubCompPacket packet, MqttPacketWriter writer)
{
writer.Write(packet.PacketIdentifier);
return(MqttPacketWriter.BuildFixedHeader(MqttControlPacketType.PubComp));
}
