Bug 410040

Summary: music player prevent lock screen
Product: [Unmaintained] kscreenlocker Reporter: Guo Yunhe <i>
Component: generalAssignee: Plasma Bugs List <plasma-bugs-null>
Status: RESOLVED NOT A BUG    
Severity: normal CC: bshah, kde
Priority: NOR    
Version First Reported In: unspecified   
Target Milestone: ---   
Platform: Other   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description Guo Yunhe 2019-07-20 17:09:48 UTC 
SUMMARY
If music player (JuK) is playing, KDE will not lock screen after no user input for a long time.

I think music player should only prevent sleep, not lock screen. People may use bluetooth headphone, they are away from computer when listening to music. Preventing lock screen is dangerous. This is different from the use case of video player.

STEPS TO REPRODUCE
1. Start JuK.
2. Play music loop.
3. Wait until screen lock happen.

OBSERVED RESULT
Screen will never be locked.

EXPECTED RESULT
Screen should still be locked.

SOFTWARE/OS VERSIONS
Operating System: openSUSE Tumbleweed 20190717
KDE Plasma Version: 5.16.2
KDE Frameworks Version: 5.59.0
Qt Version: 5.13.0
Kernel Version: 5.1.16-1-default
OS Type: 64-bit
Processors: 8 × Intel® Core™ i7-8550U CPU @ 1.80GHz
Memory: 31.2 GiB

ADDITIONAL INFORMATION
Comment 1 David Edmundson 2019-07-20 17:48:29 UTC 
KDE Screensaver does not block because of music players.

/If/ that's happening it means the music player is explicitly requesting to block the screensaver.
Comment 2 Guo Yunhe 2019-07-20 18:10:20 UTC 
In JuK, I found the related code:

QDBusInterface *pmInterface = new QDBusInterface(
                                      QStringLiteral("org.kde.Solid.PowerManagement"),
                                      QStringLiteral("/org/freedesktop/PowerManagement/Inhibit"),
                                      QStringLiteral("org.freedesktop.PowerManagement.Inhibit"),
                                      QDBusConnection::sessionBus()
                                  );

It only inhibit power management.

Power management sets the automatic screen lock after N minutes. And it is inhibited. This will prevent everything: turn off screen, lock screen, sleep. But for music player, it only needs to prevent sleep. Do you know if such a DBus interface exists?