Bug 482154 - uninstalling plasma-discover results in MANY warnings: "kf.service.services: KApplicationTrader: mimeType "x-scheme-handler/appstream" not found"
Summary: uninstalling plasma-discover results in MANY warnings: "kf.service.services: ...
Status: REPORTED
Alias: None
Product: frameworks-kservice
Classification: Frameworks and Libraries
Component: general (show other bugs)
Version: 6.0.0
Platform: Fedora RPMs Linux
: NOR normal
Target Milestone: ---
Assignee: KIO Bugs
URL:
Keywords: qt6
: 482634 (view as bug list)
Depends on:
Blocks:
 
Reported: 2024-03-01 13:50 UTC by Jayes
Modified: 2024-03-25 01:33 UTC (History)
8 users (show)

See Also:
Latest Commit:
Version Fixed In:
Sentry Crash Report:


Attachments
attachment-2588254-0.html (1.09 KB, text/html)
2024-03-02 12:44 UTC, Jayes
Details
attachment-599507-0.html (691 bytes, text/html)
2024-03-07 13:17 UTC, Jayes
Details

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Description Jayes 2024-03-01 13:50:39 UTC
SUMMARY
***
After emoving plasma-discover (6.0, which I could not select) from Fedora 40 my system log shows long rows of the same warning:
kf.service.services: KApplicationTrader: mimeType "x-scheme-handler/appstream" not found
After reinstalling the application the warnings disappear.
***

STEPS TO REPRODUCE
Run Fedora 40
Uninstall discover
Check the system log

OBSERVED RESULT
Many, many warnings

EXPECTED RESULT
No warnings

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma: Fedora 40
(available in About System)
KDE Plasma Version: 6.0.0
KDE Frameworks Version: 6.0.0
Qt Version: 6.6.2

ADDITIONAL INFORMATION
A similar bug was supposedly fixed:
https://bugs.kde.org/show_bug.cgi?id=477138
Comment 1 Nate Graham 2024-03-01 21:19:13 UTC
Well that makes sense: Discover is an AppStream handler. If you remove it, there's like no app left on the system to handle appstream:// links, so apps that try to open them fail, and this error is shown.

Bug 477138 is about correcting an issue where something was using appstream but it didn't need to be because there was another way to do what it wanted to so. But *some* things will always need to use it, and will break when there's no appstream:// URI handler installed.
Comment 2 Jayes 2024-03-02 12:44:25 UTC
Created attachment 166299 [details]
attachment-2588254-0.html

Graham,

Thanks for your explanation.

I have not seen this on plasma 5. Apparently it is specific for plasma 6 
(In addition to Fedora 40  I checked KDE Neon and it also showed this 
behavior). It is the sheer number of these warnings that made me think 
it was not intentional. I see over 60 of these warnings right after 
starting plasma. After a while there are hundreds.

regards,


On 01-03-2024 22:19, Nate Graham wrote:
> But*some*  things will always need to use it, and will break when there's no
> appstream:// URI handler installed.
Comment 3 Nicolas Fella 2024-03-07 11:27:53 UTC
*** Bug 482634 has been marked as a duplicate of this bug. ***
Comment 4 Nicolas Fella 2024-03-07 11:28:57 UTC
We should avoid the warnings
Comment 5 Nicolas Fella 2024-03-07 11:30:14 UTC
This is possibly caused by https://invent.kde.org/plasma/plasma-workspace/-/merge_requests/3556
Comment 6 Jayes 2024-03-07 13:17:34 UTC
Created attachment 166584 [details]
attachment-599507-0.html

Other distros allow complete removal of AppStream. I believe Neon does 
(for plasma 6).

If nothing handles AppStream after removal of Discover, why not allow 
removal of AppStream as well?


On 3/7/24 12:28, Nicolas Fella wrote:
> We should avoid the warnings
Comment 7 Guilherme Silva 2024-03-09 18:01:29 UTC
It'd be great to have those removed. I don't know exactly where they're coming from (I don't have Discover installed at all), but my system journal is getting constantly spammed with those:

> $ journalctl -b -o cat --no-pager | grep 'mimeType "x-scheme-handler/appstream" not found' | wc -l
> 1246
> $ uptime
> 15:00:34 up 10:41,  1 user,  load average: 0,90, 0,91, 0,82

That's 1246 messages in only 10 hours of uptime.
Comment 8 Frederick Schaefer 2024-03-24 04:04:35 UTC
I can reproduce this at will.

Baseline: Garuda KDE "Dr460nized" (Using breeze dark global theme) with Nvidia, KDE discover not installed,
plasma-desktop 6.0.2-4; kwin 6.0.2-3

Repro: mouseover any item in the Krunner menu

Result:
X session - same warnings as OP
Wayland session - same warnings as OP, (plasmashell coredumps on any panel mouseover for ... other reasons I'm trying to pinpoint).
Comment 9 Guilherme Silva 2024-03-24 07:49:35 UTC
As a workaround, I've manually disabled all warnings from kf.service.services by creating this file:

~/.config/QtProject/qtlogging.ini

With this content:

[rules]
kf.service.services.warning=false
Comment 10 Harald Sitter 2024-03-25 01:33:12 UTC
Moving to kservice since this isn't really a discover bug. Also I'm not convinced we support plasma without discover anyway.