private static MqttBasePacket DecodeConnectPacket(IMqttPacketBodyReader body)
{
ThrowIfBodyIsEmpty(body);
var packet = new MqttConnectPacket();
var protocolName = body.ReadStringWithLengthPrefix();
var protocolVersion = body.ReadByte();
if (protocolName != "MQTT" && protocolVersion != 5)
{
throw new MqttProtocolViolationException("MQTT protocol name and version do not match MQTT v5.");
}
var connectFlags = body.ReadByte();
var cleanSessionFlag = (connectFlags & 0x02) > 0;
var willMessageFlag = (connectFlags & 0x04) > 0;
var willMessageQoS = (byte)(connectFlags >> 3 & 3);
var willMessageRetainFlag = (connectFlags & 0x20) > 0;
var passwordFlag = (connectFlags & 0x40) > 0;
var usernameFlag = (connectFlags & 0x80) > 0;
packet.CleanSession = cleanSessionFlag;
if (willMessageFlag)
{
packet.WillMessage = new MqttApplicationMessage
{
QualityOfServiceLevel = (MqttQualityOfServiceLevel)willMessageQoS,
Retain = willMessageRetainFlag
};
}
packet.KeepAlivePeriod = body.ReadTwoByteInteger();
var propertiesReader = new MqttV500PropertiesReader(body);
while (propertiesReader.MoveNext())
{
if (packet.Properties == null)
{
packet.Properties = new MqttConnectPacketProperties();
}
if (propertiesReader.CurrentPropertyId == MqttPropertyId.SessionExpiryInterval)
{
packet.Properties.SessionExpiryInterval = propertiesReader.ReadSessionExpiryInterval();
}
else if (propertiesReader.CurrentPropertyId == MqttPropertyId.AuthenticationMethod)
{
packet.Properties.AuthenticationMethod = propertiesReader.ReadAuthenticationMethod();
}
else if (propertiesReader.CurrentPropertyId == MqttPropertyId.AuthenticationData)
{
packet.Properties.AuthenticationData = propertiesReader.ReadAuthenticationData();
}
else if (propertiesReader.CurrentPropertyId == MqttPropertyId.ReceiveMaximum)
{
packet.Properties.ReceiveMaximum = propertiesReader.ReadReceiveMaximum();
}
else if (propertiesReader.CurrentPropertyId == MqttPropertyId.TopicAliasMaximum)
{
packet.Properties.TopicAliasMaximum = propertiesReader.ReadTopicAliasMaximum();
}
else if (propertiesReader.CurrentPropertyId == MqttPropertyId.MaximumPacketSize)
{
packet.Properties.MaximumPacketSize = propertiesReader.ReadMaximumPacketSize();
}
else if (propertiesReader.CurrentPropertyId == MqttPropertyId.RequestResponseInformation)
{
packet.Properties.RequestResponseInformation = propertiesReader.RequestResponseInformation();
}
else if (propertiesReader.CurrentPropertyId == MqttPropertyId.RequestProblemInformation)
{
packet.Properties.RequestProblemInformation = propertiesReader.RequestProblemInformation();
}
else if (propertiesReader.CurrentPropertyId == MqttPropertyId.UserProperty)
{
if (packet.Properties.UserProperties == null)
{
packet.Properties.UserProperties = new List <MqttUserProperty>();
}
propertiesReader.AddUserPropertyTo(packet.Properties.UserProperties);
}
else
{
propertiesReader.ThrowInvalidPropertyIdException(typeof(MqttConnectPacket));
}
}
packet.ClientId = body.ReadStringWithLengthPrefix();
if (packet.WillMessage != null)
{
var willPropertiesReader = new MqttV500PropertiesReader(body);
while (willPropertiesReader.MoveNext())
{
if (willPropertiesReader.CurrentPropertyId == MqttPropertyId.PayloadFormatIndicator)
{
packet.WillMessage.PayloadFormatIndicator = propertiesReader.ReadPayloadFormatIndicator();
}
else if (willPropertiesReader.CurrentPropertyId == MqttPropertyId.MessageExpiryInterval)
{
packet.WillMessage.MessageExpiryInterval = propertiesReader.ReadMessageExpiryInterval();
}
else if (willPropertiesReader.CurrentPropertyId == MqttPropertyId.TopicAlias)
{
packet.WillMessage.TopicAlias = propertiesReader.ReadTopicAlias();
}
else if (willPropertiesReader.CurrentPropertyId == MqttPropertyId.ResponseTopic)
{
packet.WillMessage.ResponseTopic = propertiesReader.ReadResponseTopic();
}
else if (willPropertiesReader.CurrentPropertyId == MqttPropertyId.CorrelationData)
{
packet.WillMessage.CorrelationData = propertiesReader.ReadCorrelationData();
}
else if (willPropertiesReader.CurrentPropertyId == MqttPropertyId.SubscriptionIdentifier)
{
if (packet.WillMessage.SubscriptionIdentifiers == null)
{
packet.WillMessage.SubscriptionIdentifiers = new List <uint>();
}
packet.WillMessage.SubscriptionIdentifiers.Add(propertiesReader.ReadSubscriptionIdentifier());
}
else if (willPropertiesReader.CurrentPropertyId == MqttPropertyId.ContentType)
{
packet.WillMessage.ContentType = propertiesReader.ReadContentType();
}
else if (willPropertiesReader.CurrentPropertyId == MqttPropertyId.WillDelayInterval)
{
// This is a special case!
packet.Properties.WillDelayInterval = propertiesReader.ReadWillDelayInterval();
}
else if (willPropertiesReader.CurrentPropertyId == MqttPropertyId.UserProperty)
{
if (packet.WillMessage.UserProperties == null)
{
packet.WillMessage.UserProperties = new List <MqttUserProperty>();
}
propertiesReader.AddUserPropertyTo(packet.Properties.UserProperties);
}
else
{
propertiesReader.ThrowInvalidPropertyIdException(typeof(MqttPublishPacket));
}
}
packet.WillMessage.Topic = body.ReadStringWithLengthPrefix();
packet.WillMessage.Payload = body.ReadWithLengthPrefix();
}
if (usernameFlag)
{
packet.Username = body.ReadStringWithLengthPrefix();
}
if (passwordFlag)
{
packet.Password = body.ReadWithLengthPrefix();
}
return(packet);
}
