Android Question On EventMqtt_Connected (Success As Boolean) - Success = True and Mqtt.connected = False ?

[amorosik]

I am using the classic example to communicate via mqtt, and seeing in the EventMqtt_Connected(...) routine I would expect to have the agreement between the Success variable and the Connected property of the mqtt client, but it is not so

2021-10-09 17:51:43 410 - Mqtt.EventMqtt_Connected - Success = true - Mqtt_client.Connected = false

How is it possible that the Success variable (of EventMqtt_Connected sub) is True while the mqtt_client.connected property is False?

Private Sub EventMqtt_Connected (Success As Boolean)
    Log("Mqtt.EventMqtt_Connected - Success = " & Success & " - Mqtt_client.Connected=" & mqtt_client.Connected)
   
    Try
    If Success Then
            mqtt_client.Subscribe("consolle_to_applauncher", 0)
            mqtt_client.Publish2("applauncher_to_consolle", serializator.ConvertObjectToBytes(stringa_connected), 0, False)
           End If
    Catch
        Log(LastException)
    End Try
End Sub

2021-10-09 17:51:40 407 - Mqtt.EventMqtt_Connected - Success = true - Mqtt_client.Connected=true
2021-10-09 17:51:40 410 - Mqtt.EventMqtt_Connected: true
2021-10-09 17:51:40 771 Timer1sec_tick Mqtt Link: true
2021-10-09 17:51:41 379 - Mqtt.EventMqtt_Disconnected
2021-10-09 17:51:41 383 - Mqtt.EventMqtt_Connected - Success = true - Mqtt_client.Connected=false
2021-10-09 17:51:41 386 - Mqtt.EventMqtt_Connected: true
(MqttException) Client non connesso (32104)
2021-10-09 17:51:41 772 Timer1sec_tick Mqtt Link: false
2021-10-09 17:51:42 773 Timer1sec_tick Mqtt Link: false
2021-10-09 17:51:43 349 - Mqtt.Timer5sReconnectMqttEvent_Tick  mqtt_client.Connected=false
2021-10-09 17:51:43 351 - Mqtt.ConnectTo: tcp://1.2.3.4:63309 123456789
2021-10-09 17:51:43 376 - Mqtt.EventMqtt_Disconnected
2021-10-09 17:51:43 395 - Mqtt.EventMqtt_Connected - Success = true - Mqtt_client.Connected=true
2021-10-09 17:51:43 401 - Mqtt.EventMqtt_Connected: true
(MqttException) Client non connesso (32104)
2021-10-09 17:51:43 407 - Mqtt.EventMqtt_Disconnected
2021-10-09 17:51:43 410 - Mqtt.EventMqtt_Connected - Success = true - Mqtt_client.Connected=false
2021-10-09 17:51:43 413 - Mqtt.EventMqtt_Connected: true
(MqttException) Client non connesso (32104)
2021-10-09 17:51:43 774 Timer1sec_tick Mqtt Link: false
2021-10-09 17:51:44 775 Timer1sec_tick Mqtt Link: false
2021-10-09 17:51:45 775 Timer1sec_tick Mqtt Link: false
2021-10-09 17:51:46 350 - Mqtt.Timer5sReconnectMqttEvent_Tick  mqtt_client.Connected=false
2021-10-09 17:51:46 352 - Mqtt.ConnectTo: tcp://1.2.3.4:63309 123456789
2021-10-09 17:51:46 377 - Mqtt.EventMqtt_Disconnected
2021-10-09 17:51:46 396 - Mqtt.EventMqtt_Connected - Success = true - Mqtt_client.Connected=true
2021-10-09 17:51:46 399 - Mqtt.EventMqtt_Connected: true
(MqttException) Client non connesso (32104)
2021-10-09 17:51:46 409 - Mqtt.EventMqtt_Disconnected
2021-10-09 17:51:46 411 - Mqtt.EventMqtt_Connected - Success = true - Mqtt_client.Connected=false

 

[Erel]

It can happen if the connection was immediately broken. The event is raised from a different thread so there could be a few milliseconds between the time the connection was established and the time the event was executed.

 

[amorosik]

It can happen if the connection was immediately broken. The event is raised from a different thread so there could be a few milliseconds between the time the connection was established and the time the event was executed.

You mean that the event "EventMqtt_Connected" can be triggered even if the "mqtt_client.Connected" property is False, then after few millisecond also "mqtt_client.Connected" is set to True?
Than "mqtt_client.Connected" properties is not ALWAYS return the real connection state of mqtt channel?

 

[Erel]

No. I mean that there was a connection -> the event was sent to the message queue-> the connection was broken -> the event code was executed.

 

[josejad]

Than "mqtt_client.Connected" properties is not ALWAYS return the real connection state of mqtt channel?

Maybe related with this post?

Have you added the line number six to the "ConnectAndReconnect" Sub?

 Sleep(100)

 

[amorosik]

Maybe related with this post?

Have you added the line number six to the "ConnectAndReconnect" Sub?

 Sleep(100)

Yes, it is possible that the problem found is the same as you found
I followed your post and saw the change made lately
The routine I currently use is the latest version that appears on ConnectAndReconnect post, which also includes sleep (100)

 

[josejad]

Just for testing, have you try with the tcp://test.mosquitto.org server?

 

[amorosik]

Just for testing, have you try with the tcp://test.mosquitto.org server?

No, we use our Mosquitto on local pc