Pointer for those debugging web apps

vandys · 25 Jul 2017, 15:02

I of course mostly develop on my desktop Chromium browser, but every now and then I have a problem which only happens on my UBports browser. I found the file:

.cache/upstart/application-legacy-webbrowser-app-.log

which is the only place I've been able to find Javascript errors.

Also note that the browser is very, very clingy to JS source files, a reload of the overall app will often not update the contents of the JS source referenced from the app.

lduboeuf · 25 Jul 2017, 17:58

there is possibility to remotely debug browser webapps, if that helps: link

vandys · 25 Jul 2017, 18:59

@lduboeuf said in Pointer for those debugging web apps:

there is possibility to remotely debug browser webapps, if that helps: link

Nice! I never found that in any of my searches, and that's an awesome ability. It helps very much.

Note the launch command appears to have become ubuntu-app-launch instead of upstart-app-launch, but otherwise it works as advertised. My default browser is Firefox, which did not play well with this facility. Chromium on Debian works perfectly.

lduboeuf · 25 Jul 2017, 19:53

glad it helps :), might be usefull to write an up to date turorial for ubports community then

NeoTheThird · 25 Jul 2017, 23:25

<shameless stud>You can also use Logviewer to check the log and conveniently copy it to paste.ubuntu.com for later investigation, if you spot an error while you're on the go.</shameless stud>

NeoTheThird · 25 Jul 2017, 23:26

@lduboeuf said in Pointer for those debugging web apps:

write an up to date turorial for ubports community then

That would be very much appreciated! Feel free to post something on wiki.ubports.com

vandys · 26 Jul 2017, 00:01

@NeoTheThird said in Pointer for those debugging web apps:

@lduboeuf said in Pointer for those debugging web apps:

write an up to date turorial for ubports community then

That would be very much appreciated! Feel free to post something on wiki.ubports.com

Have a look at:
https://wiki.ubports.com/wiki/Web-Browser-app-debugging
and wordsmith it if you can think of nice changes. Thanks!

(BTW, not clear how to link it into the rest of the document hierarchy.)

Fla · 3 Oct 2020, 09:41

I'm discovering this thread. The tuto URL changed and now is http://docs.ubports.com/en/latest/appdev/webapp/webdebug.html

However, it looks like it doesn't work anymore. I did the 3 steps:

export QTWEBENGINE_REMOTE_DEBUGGING=0.0.0.0:9221
morph-browser --desktop_file_hint=/usr/share/applications/morph-browser.desktop [web_site_url]
Open http://YOUR_UT_IP_ADDRESS:9221 with chromium

And it says connection refused.

AppLee · 3 Oct 2020, 10:33

@Fla
IIRC 3 years ago the browser was not yet Morph.
So I guess a lot changed since.

Maybe someone know the modern way to debug webapps with Morph.
It might be better to open a new thread in this regard I guess

Fla · 3 Oct 2020, 11:36

I think the doc has been updated since then, as the command is morph-browser as stated above.

AppLee · 3 Oct 2020, 12:13

@Fla
Oh, right.
Sorry I didn't pay enough attention to the command lines.