//public int Publish(string topic, MqttPayload payload, QoS qos, bool retained)
//{
// return 0;
//}
public int Publish(MqttParcel parcel)
{
ushort messageId = MessageId;
int index = 0;
int tmp = 0;
int fixedHeader = 0;
int varHeader = 0;
int payload = 0;
int remainingLength = 0;
int returnCode = 0;
byte[] buffer = null;
// Setup a UTF8 encoder
UTF8Encoding encoder = new UTF8Encoding();
// Encode the topic
byte[] utf8Topic = Encoding.UTF8.GetBytes(parcel.Topic);
// Some error checking
// Topic contains wildcards
if ((parcel.Topic.IndexOf('#') != -1) || (parcel.Topic.IndexOf('+') != -1))
{
//return Constants.TOPIC_WILDCARD_ERROR;
}
// Topic is too long or short
if ((utf8Topic.Length > Constants.MAX_TOPIC_LENGTH) || (utf8Topic.Length < Constants.MIN_TOPIC_LENGTH))
{
//return Constants.TOPIC_LENGTH_ERROR;
}
// Calculate the size of the var header
varHeader += 2; // Topic Name Length (MSB, LSB)
varHeader += utf8Topic.Length; // Length of the topic
// Calculate the size of the fixed header
fixedHeader++; // byte 1
// Calculate the payload
payload = parcel.Payload.ToString().Length;
// Calculate the remaining size
remainingLength = varHeader + payload;
// Check that remaining length will fit into 4 encoded bytes
if (remainingLength > Constants.MAXLENGTH)
{
//return Constants.MESSAGE_LENGTH_ERROR;
}
// Add space for each byte we need in the fixed header to store the length
tmp = remainingLength;
while (tmp > 0)
{
fixedHeader++;
tmp = tmp / 128;
};
// End of Fixed Header
// Build buffer for message
buffer = new byte[fixedHeader + varHeader + payload];
// Start of Fixed header
// Publish (3.3)
buffer[index++] = Constants.MQTT_PUBLISH_TYPE;
// Encode the fixed header remaining length
// Add remaining length
index = doRemainingLength(remainingLength, index, buffer);
// End Fixed Header
// Start of Variable header
// Length of topic name
buffer[index++] = (byte)(utf8Topic.Length / 256); // Length MSB
buffer[index++] = (byte)(utf8Topic.Length % 256); // Length LSB
// Topic
for (var i = 0; i < utf8Topic.Length; i++)
{
buffer[index++] = utf8Topic[i];
}
// End of variable header
// Start of Payload
// Message (Length is accounted for in the fixed header)
for (var i = 0; i < parcel.Payload.TrimmedBuffer.Length; i++)
{
buffer[index++] = (byte)parcel.Payload.TrimmedBuffer[i];
}
// End of Payload
try
{
returnCode = _socket.Send(buffer, buffer.Length, 0);
}
catch (Exception ex)
{
_logger.Error("Error on publish " + ex.Message);
}
if (returnCode < buffer.Length)
{
//return Constants.CONNECTION_ERROR;
}
return messageId;
}
private static void StayAlive(Object state)
{
var topic = String.Concat("SA", _settings.Key);
var parcel = new MqttParcel(topic, new MqttPayload(topic), QoS.BestEfforts, false);
_mqtt.Publish(parcel);
}
