identifierRejected and a disconnection origin of none

[3gcodes]

I know there's a similar issue from 2018 that is closed, but I'm getting the same error. I'm using this as my example code...

https://medium.com/@emqtt/using-mqtt-in-the-flutter-project-6a5d90179c8b

Flutter version info:

Flutter 1.22.6 • channel stable • https://github.com/flutter/flutter.git
Framework • revision 9b2d32b605 (3 weeks ago) • 2021-01-22 14:36:39 -0800
Engine • revision 2f0af37152
Tools • Dart 2.10.5

And getting the following:

I/flutter ( 9784): 2-2021-02-12 20:25:05.602730 -- MqttConnectionHandlerBase::connect - server 192.168.0.34, port 1883
I/flutter ( 9784): 2-2021-02-12 20:25:05.603044 -- SynchronousMqttServerConnectionHandler::internalConnect entered
I/flutter ( 9784): 2-2021-02-12 20:25:05.603131 -- SynchronousMqttServerConnectionHandler::internalConnect - initiating connection try 0, auto reconnect in progress false
I/flutter ( 9784): 2-2021-02-12 20:25:05.603230 -- SynchronousMqttServerConnectionHandler::internalConnect - insecure TCP selected
I/flutter ( 9784): 2-2021-02-12 20:25:05.603668 -- SynchronousMqttServerConnectionHandler::internalConnect - calling connect
I/flutter ( 9784): 2-2021-02-12 20:25:05.603767 -- MqttNormalConnection::connect - entered
I/flutter ( 9784): 2-2021-02-12 20:25:05.662356 -- MqttServerConnection::_startListening
I/flutter ( 9784): 2-2021-02-12 20:25:05.662832 -- SynchronousMqttServerConnectionHandler::internalConnect - connection complete
I/flutter ( 9784): 2-2021-02-12 20:25:05.663126 -- SynchronousMqttServerConnectionHandler::internalConnect sending connect message
I/flutter ( 9784): 2-2021-02-12 20:25:05.663404 -- MqttConnectionHandlerBase::sendMessage - MQTTMessage of type MqttMessageType.connect
I/flutter ( 9784): Header: MessageType = MqttMessageType.connect, Duplicate = false, Retain = false, Qos = MqttQos.atMostOnce, Size = 0
I/flutter ( 9784): Connect Variable Header: ProtocolName=MQIsdp, ProtocolVersion=3, ConnectFlags=Connect Flags: Reserved1=false, CleanStart=true, WillFlag=true, WillQos=MqttQos.atLeastOnce, WillRetain=false, PasswordFlag=false, UserNameFlag=false, KeepAlive=60
I/flutter ( 9784): MqttConnectPayload - client identifier is : 
I/flutter ( 9784): 2-2021-02-12 20:25:05.666395 -- SynchronousMqttServerConnectionHandler::internalConnect - pre sleep, state = Connection status is connecting with return code of noneSpecified and a disconnection origin of none
I/flutter ( 9784): 2-2021-02-12 20:25:05.670081 -- MqttConnection::_onData
I/flutter ( 9784): 2-2021-02-12 20:25:05.670414 -- MqttServerConnection::_onData - message received MQTTMessage of type MqttMessageType.connectAck
I/flutter ( 9784): Header: MessageType = MqttMessageType.connectAck, Duplicate = false, Retain = false, Qos = MqttQos.atMostOnce, Size = 2
I/flutter ( 9784): Connect Variable Header: TopicNameCompressionResponse={0}, ReturnCode={MqttConnectReturnCode.identifierRejected}
I/flutter ( 9784): 2-2021-02-12 20:25:05.670585 -- MqttServerConnection::_onData - message available event fired
I/flutter ( 9784): 2-2021-02-12 20:25:05.671317 -- MqttConnectionHandlerBase::_connectAckProcessor
I/flutter ( 9784): 2-2021-02-12 20:25:05.671420 -- MqttConnectionHandlerBase::_connectAckProcessor connection rejected
I/flutter ( 9784): 2-2021-02-12 20:25:05.671510 -- MqttConnectionHandlerBase::_performConnectionDisconnect entered
I/flutter ( 9784): 2-2021-02-12 20:25:05.671632 -- MqttConnectionHandlerBase:: cancelling connect timer
I/flutter ( 9784): 2-2021-02-12 20:25:05.672389 -- MqttConnectionBase::_onDone - calling disconnected callback
I/flutter ( 9784): 2-2021-02-12 20:25:05.672538 -- SynchronousMqttServerConnectionHandler::internalConnect - post sleep, state = Connection status is disconnected with return code of identifierRejected and a disconnection origin of none
I/flutter ( 9784): 2-2021-02-12 20:25:05.672625 -- SynchronousMqttServerConnectionHandler::internalConnect - initiating connection try 1, auto reconnect in progress false
I/flutter ( 9784): 2-2021-02-12 20:25:05.672687 -- SynchronousMqttServerConnectionHandler::internalConnect - insecure TCP selected
I/flutter ( 9784): 2-2021-02-12 20:25:05.672755 -- SynchronousMqttServerConnectionHandler::internalConnect - calling connect
I/flutter ( 9784): 2-2021-02-12 20:25:05.672805 -- MqttNormalConnection::connect - entered
I/flutter ( 9784): 2-2021-02-12 20:25:05.689565 -- MqttServerConnection::_startListening
I/flutter ( 9784): 2-2021-02-12 20:25:05.690119 -- SynchronousMqttServerConnectionHandler::internalConnect - connection complete
I/flutter ( 9784): 2-2021-02-12 20:25:05.690352 -- SynchronousMqttServerConnectionHandler::internalConnect sending connect message
I/flutter ( 9784): 2-2021-02-12 20:25:05.690550 -- MqttConnectionHandlerBase::sendMessage - MQTTMessage of type MqttMessageType.connect
I/flutter ( 9784): Header: MessageType = MqttMessageType.connect, Duplicate = false, Retain = false, Qos = MqttQos.atMostOnce, Size = 38
I/flutter ( 9784): Connect Variable Header: ProtocolName=MQIsdp, ProtocolVersion=3, ConnectFlags=Connect Flags: Reserved1=false, CleanStart=true, WillFlag=true, WillQos=MqttQos.atLeastOnce, WillRetain=false, PasswordFlag=false, UserNameFlag=false, KeepAlive=60
I/flutter ( 9784): MqttConnectPayload - client identifier is : 
I/flutter ( 9784): 2-2021-02-12 20:25:05.692258 -- SynchronousMqttServerConnectionHandler::internalConnect - pre sleep, state = Connection status is connecting with return code of noneSpecified and a disconnection origin of none
I/flutter ( 9784): 2-2021-02-12 20:25:05.695322 -- MqttConnection::_onData
I/flutter ( 9784): 2-2021-02-12 20:25:05.695474 -- MqttServerConnection::_onData - message received MQTTMessage of type MqttMessageType.connectAck
I/flutter ( 9784): Header: MessageType = MqttMessageType.connectAck, Duplicate = false, Retain = false, Qos = MqttQos.atMostOnce, Size = 2
I/flutter ( 9784): Connect Variable Header: TopicNameCompressionResponse={0}, ReturnCode={MqttConnectReturnCode.identifierRejected}
I/flutter ( 9784): 2-2021-02-12 20:25:05.695566 -- MqttServerConnection::_onData - message available event fired
I/flutter ( 9784): 2-2021-02-12 20:25:05.695650 -- MqttConnectionHandlerBase::_connectAckProcessor
I/flutter ( 9784): 2-2021-02-12 20:25:05.695708 -- MqttConnectionHandlerBase::_connectAckProcessor connection rejected
I/flutter ( 9784): 2-2021-02-12 20:25:05.695777 -- MqttConnectionHandlerBase::_performConnectionDisconnect entered
I/flutter ( 9784): 2-2021-02-12 20:25:05.695836 -- MqttConnectionHandlerBase:: cancelling connect timer
I/flutter ( 9784): 2-2021-02-12 20:25:05.696047 -- MqttConnectionBase::_onDone - calling disconnected callback
I/flutter ( 9784): 2-2021-02-12 20:25:05.696120 -- SynchronousMqttServerConnectionHandler::internalConnect - post sleep, state = Connection status is disconnected with return code of identifierRejected and a disconnection origin of none
I/flutter ( 9784): 2-2021-02-12 20:25:05.696170 -- SynchronousMqttServerConnectionHandler::internalConnect - initiating connection try 2, auto reconnect in progress false
I/flutter ( 9784): 2-2021-02-12 20:25:05.696574 -- SynchronousMqttServerConnectionHandler::internalConnect - insecure TCP selected
I/flutter ( 9784): 2-2021-02-12 20:25:05.696646 -- SynchronousMqttServerConnectionHandler::internalConnect - calling connect
I/flutter ( 9784): 2-2021-02-12 20:25:05.696697 -- MqttNormalConnection::connect - entered
I/flutter ( 9784): 2-2021-02-12 20:25:05.708657 -- MqttServerConnection::_startListening
I/flutter ( 9784): 2-2021-02-12 20:25:05.708823 -- SynchronousMqttServerConnectionHandler::internalConnect - connection complete
I/flutter ( 9784): 2-2021-02-12 20:25:05.708878 -- SynchronousMqttServerConnectionHandler::internalConnect sending connect message
I/flutter ( 9784): 2-2021-02-12 20:25:05.708960 -- MqttConnectionHandlerBase::sendMessage - MQTTMessage of type MqttMessageType.connect
I/flutter ( 9784): Header: MessageType = MqttMessageType.connect, Duplicate = false, Retain = false, Qos = MqttQos.atMostOnce, Size = 38
I/flutter ( 9784): Connect Variable Header: ProtocolName=MQIsdp, ProtocolVersion=3, ConnectFlags=Connect Flags: Reserved1=false, CleanStart=true, WillFlag=true, WillQos=MqttQos.atLeastOnce, WillRetain=false, PasswordFlag=false, UserNameFlag=false, KeepAlive=60
I/flutter ( 9784): MqttConnectPayload - client identifier is : 
I/flutter ( 9784): 2-2021-02-12 20:25:05.709719 -- SynchronousMqttServerConnectionHandler::internalConnect - pre sleep, state = Connection status is connecting with return code of noneSpecified and a disconnection origin of none
I/flutter ( 9784): 2-2021-02-12 20:25:05.713511 -- MqttConnection::_onData
I/flutter ( 9784): 2-2021-02-12 20:25:05.713653 -- MqttServerConnection::_onData - message received MQTTMessage of type MqttMessageType.connectAck
I/flutter ( 9784): Header: MessageType = MqttMessageType.connectAck, Duplicate = false, Retain = false, Qos = MqttQos.atMostOnce, Size = 2
I/flutter ( 9784): Connect Variable Header: TopicNameCompressionResponse={0}, ReturnCode={MqttConnectReturnCode.identifierRejected}
I/flutter ( 9784): 2-2021-02-12 20:25:05.713730 -- MqttServerConnection::_onData - message available event fired
I/flutter ( 9784): 2-2021-02-12 20:25:05.713811 -- MqttConnectionHandlerBase::_connectAckProcessor
I/flutter ( 9784): 2-2021-02-12 20:25:05.713867 -- MqttConnectionHandlerBase::_connectAckProcessor connection rejected
I/flutter ( 9784): 2-2021-02-12 20:25:05.713920 -- MqttConnectionHandlerBase::_performConnectionDisconnect entered
I/flutter ( 9784): 2-2021-02-12 20:25:05.713973 -- MqttConnectionHandlerBase:: cancelling connect timer
I/flutter ( 9784): 2-2021-02-12 20:25:05.716320 -- MqttConnectionBase::_onDone - calling disconnected callback
I/flutter ( 9784): 2-2021-02-12 20:25:05.716455 -- SynchronousMqttServerConnectionHandler::internalConnect - post sleep, state = Connection status is disconnected with return code of identifierRejected and a disconnection origin of none
I/flutter ( 9784): 2-2021-02-12 20:25:05.716550 -- SynchronousMqttServerConnectionHandler::internalConnect failed
I/flutter ( 9784): Exception: mqtt-client::NoConnectionException: The maximum allowed connection attempts ({3}) were exceeded. The broker is not responding to the connection request message correctly The return code is MqttConnectReturnCode.identifierRejected
I/flutter ( 9784): 2-2021-02-12 20:25:05.716842 -- MqttConnectionHandlerBase::disconnect - entered
I/flutter ( 9784): 2-2021-02-12 20:25:05.716915 -- MqttConnectionHandlerBase::_performConnectionDisconnect entered
I/flutter ( 9784): Disconnected

[shamblett]

You are getting a connect ack back with a reason code of 'identifier rejected'.

Looking at the logs you are not setting a client identifier -

I/flutter ( 9784): MqttConnectPayload - client identifier is : 

This will affect some brokers, which broker are you using?

You don't say what number the closed issue is however this seems to not be an error with the client.

[3gcodes]

Thanks for the info. However, I am setting the client id.

MqttServerClient client = MqttServerClient.withPort('192.168.0.34', 'client-1', 1883);

I even tried

client.clientIdentifier = "client-1";

I have tried hivemq and emqx, but giving the same results. I can connect to both using MQTT X. The old issue number is https://github.com/ThomDietrich/miflora-mqtt-daemon/issues/55.

[3gcodes]

Okay, I figured it out. I had to add .withClientIdentifier("client-1") to my MqttConnectionMessage. But I'm unsure why, if I've set it on the client itself.

[shamblett]

Yep, if you supply your own connect message the client identifier you specify in the constructor isn't used, you are expected to supply this yourself as you have discovered. I think this is misleading, its not obvious you need to do this, I'll put a fix in so people don't get caught by this again.

[3gcodes]

Terrific! Thanks.

[shamblett]

Complete, package re published at version 9.1.0.