Discourse stuck on loading screen after update (v2.4.0, Discourse 3.2.0)

[ari]

After the last update, I'm no longer able to view my forum. Restarting app didn't help.

When I load the app in browser, I see a loading indicator bouncing indefinitely. The browser console suggests that there is an issue with Ember (v5.5.0):

I took a look in my Cloudron app logs, and don't see any notable errors. Saw a few iterations of these two messages while on the loading screen, which I suspect is normal/expected, but wanted to mention just in case.

Feb 07 08:45:00 Redirected to <...>/login
Feb 07 08:45:00 Filter chain halted as :redirect_to_login_if_required rendered or redirected

(This Discourse is configured to put all functionality behind a login.)

[girish]

@ari so package 2.3.0 worked and only 2.4.0 is causing the above error?

[girish]

One thing is that in 2.4.0 we raised the memory limit to 4GB . Otherwise, it just runs out of memory at times. If you go to App -> Resources . Can you bump the memory even more and see if that helps?

[ari]

This post is deleted!

[ari]

@girish Looking at the Event Log tab, I see that I was running v2.2.3 until this week and then updated to 2.3 and then 2.4 in a day. So entirely possible this broke with v2.3.0.

[girish]

@ari If you clone from the 2.3.0 backup, it will help us narrow down the issue.

[Locutus]

I had the same problem as you did. Turning off the discourse-follow plugin resolved the issue for me. It could be either that or one of your other plugins.

[girish]

Yeah, discourse plugins are just cloned from git . At the same time, they aren't compatible between releases. This just breaks installations Best not to install plugins unless you are paying attention.

[ari]

@girish Rolling back now. Will report what I find.

[ari]

Rolling back to my 2.3.0 backup fixed the problem. Seems like the issue entered in 2.3.0=>2.4.0.

[ari]

I have four plugins installed, but only one is active. Could an inactive plugin still cause issues?

[girish]

The main difference in 2.4.0 is that they put some ember based asset building . Maybe one or more plugins are incompatible. I don't know if inactive plugins can cause problems.

[ari]

I just discovered Safe Mode, and that helped me narrow the source of the issue to either the theme and theme components that I'm using. Next step is tracking that down, but this helped considerably.

Wanted to share in case others run into the same issue! Visit <discourse_app>/safe-mode to toggle off three different potential sources of issues.

[ari]

Next step was visiting https://learning.aribadernatal.com/admin/customize/themes and checking for updates on the theme and each theme component. After installing all of the updates, I exited Safe Mode and visit in a new window. Discourse is accessible again!

[ari]

@girish Two ideas based on this experience for small additions to https://docs.cloudron.io/apps/discourse/

1. Would be great to mention Safe Mode as a useful debugging tool on this page.
2. Would be helpful to add a section on how to uninstall plugins. When I searched online, everything pointed to removing an entry from app.yml, which doesn't exist in the Cloudron setup. I'd imagine it's a modified version of the current section on installing plugins: removing a directory and perhaps re-running plugin:install_all_gems but that's just a guess.

[eddowding]

+1 on guidance how to uninstall plug-ins from the CLI please