Android Question MQTT with CA file

[August Jimenez]

HI,

I'm developing a MQTT client and I would like to know how to connect with a broker using a certificate file.

The connection must use mqtts/tls protocol.

Thanks

 

[udg]

In my Starter service, I use something like this:

Sub Process_Globals
  Private mqtt As MqttClient 
  Private ServerAndPort As String = "ssl://<your MQTT broker IP address>:<port number>"
  ...
End Sub

Public Sub Connect(ThisUser As TUser)
   CurrentUser = ThisUser    'this is a type used in my program, you can use a simple integer
   If mqtt.Connected Then mqtt.Close
   mqtt.Initialize("mqtt", ServerAndPort, CurrentUser.Name)
   Dim mo As MqttConnectOptions
   mo.Initialize(ThisUser.Name,ThisUser.Pwd)
   'this message will be sent if the client is disconnected unexpectedly.
   mo.SetLastWill("servizio/disconnect", CurrentUser.Name.GetBytes("UTF8"), 0, False)
   mqtt.Connect2(mo)
End Sub

Main calls Connect when needed.

My MQTT broker server resides on a cheap VPS server where I installed a free Let'sEncrypt certificate which I have to renew every three months.

 

[August Jimenez]

Thanks udg, but I need also to add a CA file. If not, I wil not connect with the broker.

Regards

 

[udg]

Sorry, I missed the "file" part of your question. Time for a coffe..

 

[Erel]

Do you need to authenticate the client or are you trying to avoid a SSL error?
Workaround for the later case: https://www.b4x.com/android/forum/t...g-into-ssl-throws-an-error.96390/#post-608320

 

[August Jimenez]

Udg, of course ;-)

Erel, I need to authenticate the client.

Thanks to both.

 

[Erel]

This is currently not supported.

 

[August Jimenez]

Thanks, Erel. I have used the second option you have mentioned, and it works, without specified the CA file.

I will open another thread about the publish method.

Regards