openSAP HANA 7 exercise 4.4 - websocket connection immediately closes upon loading the url

[FranklinAsis]

Hi,

Installation scenario: Hana express edition on preconfigured VM on my laptop.

Issue: upon running the web module and accessing /exerciseAsync, the message "Websocket Connection Closed" appears immediately. Pressing the buttons does nothing.

I believe the message is coded in the App.controller.js. Unfortunately i couldn't debug whats happening, i am getting a "could not connect to websockets" error when trying to debug(i have raised that question here as well).

Best,

Frank

[thomas_jung]

So it sounds like web sockets in general aren't working on your system since trying to debug is also giving a similar websockets error. HANA Express uses a self signed certificate. Are you getting a certificate exception or security warning in your browser? How are you getting around those security messages? Most likely the websockets are facing a similar security situation with the self signed certificate, but there is no interactive way for you to say its OK. That is why I personally always add the HANA Express certificate to the trusted root of the certificate store in the browser so that all the access methods then trust the certificate.

[FranklinAsis]

Hi Thomas,

Sorry for putting this in 2 places.

Anyway, after looking at the browser's dev tools, it does say NET::ERR_CERT_AUTHORITY_INVALID error.

How are you getting around those security messages? -> I didn't get any except for my antivirus' warning about ARP Cache Poisoning attack from HXE's Ip address - to which i added to the exception list of my antivirus.

I tried this link to export/import the certificate to the 'trusted root certification authorities' of my browser - it does say import was successful but it looks like it wasn't because i couldnt find what i just uploaded - which i think is another thing on its own..

Anyway, if you have other ways to do it, please let me know. I've been an ABAP Dev for most of my developer career and i've just began learning new development languages outside ABAP, I am enjoying it, but there are a lot of struggles along the way as expected. Having said that, I really appreciate you taking the time looking at my issues and helping me out.

Best,

Frank

[FranklinAsis]

Hi Thomas,

I noticed that the hxe certificate looks weirdly incomplete:

I'm thinking that, this could be the reason why exporting and importing this to the Trusted Root CA of my browser doesn't help.

Is there a way to regenerate the certificate from XS command line? Please advise. Thanks!

Best,

Frank