VERY basic feature gaps. What am I missing? Can't connect, can't debug, can't stop reconnect attempts,, etc. :(

[MrPeteH]

I've got MQTTX desktop installed. Have had a running EMQX server for 2 years. Trying to diagnose a problem in a separate subscribe app. This seemed a good way to dig in...

a) On first time open of app I set up a connection.
BUG? Once I hit "connect", I got endless "Connect failed" every 4 seconds. Even after disabling auto-reconnect. And there's no button to turn OFF the connect attempts???
BUG? I turned on DEBUG logging. I got a DEBUG log message that the connection closed immediately. Zero other info. AND, on reload of the app, DEBUG logging doesn't do anything at all. No debug log lines no matter what I've tried. :(

QUESTION: is this as-intended, that there's no button to stop the auto-reconnects? Can enable but not disable connection attempts?

b) I was hoping to find a log that would explain why the connect failed. A hint at least ;)... Could NOT find the log for several minutes.
SUGGESTION: Include the log viewer in the top View menu.
I eventually discovered the side bar menu. Not at all obvious. Found nothing anywhere leading me to the log-view icon.

c) How to debug my issue?

• I now see the log. I can make connect attempts. Wireshark shows the same packet pattern as I see in my other app.
• The only info I'm getting from MQTTX is "Connect failed".
• QUESTION: Can MQTTX provide any assistance in diagnosing connection failures? I would love to see an interpretation of the handshakes and responses!
  - How do y'all debug these things?

d) BUG: MQTTX doesn't implement Websockets properly

• As part of working through this, I tried downgrading from WSS to WS - this also fails but wireshark shows the issue:
  • In MQTTX my connection is configured as ws://foo.example.com
  • Wireshark shows the request URI is http://foo.example.com:8083/... not ws://foo.example.com...
    (AFAIK, that's incorrect? I'm not an expert, perhaps this is ok?)

[MrPeteH]

I have made very significant progress. NOT in original order:
a) First-time use BUG confirmed
b) I still would suggest including the log in the top-line menu ;)
d) Websockets BUG confirmed. And this also helps explain the lack of debug info in the log
c) Significant finding for debugging:

• Even if what you want is websockets, begin with use of plain HTTP then HTTPS (TLS)
• Plain HTTP ensures you can connect in the simplest case
• Simple HTTPS ensures all is well with TLS connections, including certificates etc
• Once HTTPS is functioning, most likely the switch to web sockets will go smoothly

In my use case, the HTTPS test in MQTTX revealed an error message not seen elsewhere: my TLS certificate had expired! Fixing that took care of everything :)