static byte EncodeSubscribePacket(MqttSubscribePacket packet, MqttBufferWriter bufferWriter)
{
if (!packet.TopicFilters.Any())
{
throw new MqttProtocolViolationException("At least one topic filter must be set [MQTT-3.8.3-3].");
}
if (packet.PacketIdentifier == 0)
{
throw new MqttProtocolViolationException("Subscribe packet has no packet identifier.");
}
bufferWriter.WriteTwoByteInteger(packet.PacketIdentifier);
if (packet.TopicFilters?.Count > 0)
{
foreach (var topicFilter in packet.TopicFilters)
{
bufferWriter.WriteString(topicFilter.Topic);
bufferWriter.WriteByte((byte)topicFilter.QualityOfServiceLevel);
}
}
return(MqttBufferWriter.BuildFixedHeader(MqttControlPacketType.Subscribe, 0x02));
}
static byte EncodeSubAckPacket(MqttSubAckPacket packet, MqttBufferWriter bufferWriter)
{
if (packet.PacketIdentifier == 0)
{
throw new MqttProtocolViolationException("SubAck packet has no packet identifier.");
}
bufferWriter.WriteTwoByteInteger(packet.PacketIdentifier);
if (packet.ReasonCodes.Any())
{
foreach (var packetSubscribeReturnCode in packet.ReasonCodes)
{
if (packetSubscribeReturnCode == MqttSubscribeReasonCode.GrantedQoS0)
{
bufferWriter.WriteByte((byte)MqttSubscribeReturnCode.SuccessMaximumQoS0);
}
else if (packetSubscribeReturnCode == MqttSubscribeReasonCode.GrantedQoS1)
{
bufferWriter.WriteByte((byte)MqttSubscribeReturnCode.SuccessMaximumQoS1);
}
else if (packetSubscribeReturnCode == MqttSubscribeReasonCode.GrantedQoS2)
{
bufferWriter.WriteByte((byte)MqttSubscribeReturnCode.SuccessMaximumQoS2);
}
else
{
bufferWriter.WriteByte((byte)MqttSubscribeReturnCode.Failure);
}
}
}
return(MqttBufferWriter.BuildFixedHeader(MqttControlPacketType.SubAck));
}
static byte EncodeUnsubAckPacket(MqttUnsubAckPacket packet, MqttBufferWriter bufferWriter)
{
if (packet.PacketIdentifier == 0)
{
throw new MqttProtocolViolationException("UnsubAck packet has no packet identifier.");
}
bufferWriter.WriteTwoByteInteger(packet.PacketIdentifier);
return(MqttBufferWriter.BuildFixedHeader(MqttControlPacketType.UnsubAck));
}
static byte EncodePublishPacket(MqttPublishPacket packet, MqttBufferWriter bufferWriter)
{
ValidatePublishPacket(packet);
bufferWriter.WriteString(packet.Topic);
if (packet.QualityOfServiceLevel > MqttQualityOfServiceLevel.AtMostOnce)
{
if (packet.PacketIdentifier == 0)
{
throw new MqttProtocolViolationException("Publish packet has no packet identifier.");
}
bufferWriter.WriteTwoByteInteger(packet.PacketIdentifier);
}
else
{
if (packet.PacketIdentifier > 0)
{
throw new MqttProtocolViolationException("Packet identifier must be empty if QoS == 0 [MQTT-2.3.1-5].");
}
}
// The payload is the past part of the packet. But it is not added here in order to keep
// memory allocation low.
byte fixedHeader = 0;
if (packet.Retain)
{
fixedHeader |= 0x01;
}
fixedHeader |= (byte)((byte)packet.QualityOfServiceLevel << 1);
if (packet.Dup)
{
fixedHeader |= 0x08;
}
return(MqttBufferWriter.BuildFixedHeader(MqttControlPacketType.Publish, fixedHeader));
}
static byte EncodeUnsubscribePacket(MqttUnsubscribePacket packet, MqttBufferWriter bufferWriter)
{
if (!packet.TopicFilters.Any())
{
throw new MqttProtocolViolationException("At least one topic filter must be set [MQTT-3.10.3-2].");
}
if (packet.PacketIdentifier == 0)
{
throw new MqttProtocolViolationException("Unsubscribe packet has no packet identifier.");
}
bufferWriter.WriteTwoByteInteger(packet.PacketIdentifier);
if (packet.TopicFilters?.Any() == true)
{
foreach (var topicFilter in packet.TopicFilters)
{
bufferWriter.WriteString(topicFilter);
}
}
return(MqttBufferWriter.BuildFixedHeader(MqttControlPacketType.Unsubscibe, 0x02));
}
byte EncodeConnectPacketV311(MqttConnectPacket packet, MqttBufferWriter bufferWriter)
{
ValidateConnectPacket(packet);
bufferWriter.WriteString("MQTT");
bufferWriter.WriteByte(4); // 3.1.2.2 Protocol Level 4
byte connectFlags = 0x0;
if (packet.CleanSession)
{
connectFlags |= 0x2;
}
if (packet.WillFlag)
{
connectFlags |= 0x4;
connectFlags |= (byte)((byte)packet.WillQoS << 3);
if (packet.WillRetain)
{
connectFlags |= 0x20;
}
}
if (packet.Password != null && packet.Username == null)
{
throw new MqttProtocolViolationException("If the User Name Flag is set to 0, the Password Flag MUST be set to 0 [MQTT-3.1.2-22].");
}
if (packet.Password != null)
{
connectFlags |= 0x40;
}
if (packet.Username != null)
{
connectFlags |= 0x80;
}
bufferWriter.WriteByte(connectFlags);
bufferWriter.WriteTwoByteInteger(packet.KeepAlivePeriod);
bufferWriter.WriteString(packet.ClientId);
if (packet.WillFlag)
{
bufferWriter.WriteString(packet.WillTopic);
bufferWriter.WriteBinaryData(packet.WillMessage);
}
if (packet.Username != null)
{
bufferWriter.WriteString(packet.Username);
}
if (packet.Password != null)
{
bufferWriter.WriteBinaryData(packet.Password);
}
return(MqttBufferWriter.BuildFixedHeader(MqttControlPacketType.Connect));
}
void Write(MqttPropertyId id, ushort value)
{
_bufferWriter.WriteByte((byte)id);
_bufferWriter.WriteTwoByteInteger(value);
}
byte EncodeConnectPacket(MqttConnectPacket packet)
{
if (string.IsNullOrEmpty(packet.ClientId) && !packet.CleanSession)
{
throw new MqttProtocolViolationException("CleanSession must be set if ClientId is empty [MQTT-3.1.3-7].");
}
_bufferWriter.WriteString("MQTT");
_bufferWriter.WriteByte(5); // [3.1.2.2 Protocol Version]
byte connectFlags = 0x0;
if (packet.CleanSession)
{
connectFlags |= 0x2;
}
if (packet.WillFlag)
{
connectFlags |= 0x4;
connectFlags |= (byte)((byte)packet.WillQoS << 3);
if (packet.WillRetain)
{
connectFlags |= 0x20;
}
}
if (packet.Password != null && packet.Username == null)
{
throw new MqttProtocolViolationException("If the User Name Flag is set to 0, the Password Flag MUST be set to 0 [MQTT-3.1.2-22].");
}
if (packet.Password != null)
{
connectFlags |= 0x40;
}
if (packet.Username != null)
{
connectFlags |= 0x80;
}
_bufferWriter.WriteByte(connectFlags);
_bufferWriter.WriteTwoByteInteger(packet.KeepAlivePeriod);
_propertiesWriter.WriteSessionExpiryInterval(packet.SessionExpiryInterval);
_propertiesWriter.WriteAuthenticationMethod(packet.AuthenticationMethod);
_propertiesWriter.WriteAuthenticationData(packet.AuthenticationData);
_propertiesWriter.WriteRequestProblemInformation(packet.RequestProblemInformation);
_propertiesWriter.WriteRequestResponseInformation(packet.RequestResponseInformation);
_propertiesWriter.WriteReceiveMaximum(packet.ReceiveMaximum);
_propertiesWriter.WriteTopicAliasMaximum(packet.TopicAliasMaximum);
_propertiesWriter.WriteMaximumPacketSize(packet.MaximumPacketSize);
_propertiesWriter.WriteUserProperties(packet.UserProperties);
_propertiesWriter.WriteTo(_bufferWriter);
_propertiesWriter.Reset();
_bufferWriter.WriteString(packet.ClientId);
if (packet.WillFlag)
{
_propertiesWriter.WritePayloadFormatIndicator(packet.WillPayloadFormatIndicator);
_propertiesWriter.WriteMessageExpiryInterval(packet.WillMessageExpiryInterval);
_propertiesWriter.WriteResponseTopic(packet.WillResponseTopic);
_propertiesWriter.WriteCorrelationData(packet.WillCorrelationData);
_propertiesWriter.WriteContentType(packet.WillContentType);
_propertiesWriter.WriteUserProperties(packet.WillUserProperties);
_propertiesWriter.WriteWillDelayInterval(packet.WillDelayInterval);
_propertiesWriter.WriteTo(_bufferWriter);
_propertiesWriter.Reset();
_bufferWriter.WriteString(packet.WillTopic);
_bufferWriter.WriteBinaryData(packet.WillMessage);
}
if (packet.Username != null)
{
_bufferWriter.WriteString(packet.Username);
}
if (packet.Password != null)
{
_bufferWriter.WriteBinaryData(packet.Password);
}
return(MqttBufferWriter.BuildFixedHeader(MqttControlPacketType.Connect));
}
