Standardizing Qt logging categories used in KF

[Friedrich W. H. Kossebau]

Hi,

while going through the KF modules to adapt to the new 
ecm_qt_install_logging_categories() macro* to auto-generate KDebugSettings 
.categories (& .renamecategories) files I once more found there is no real 
naming pattern for the logging categories.
* https://api.kde.org/ecm/module/ECMQtDeclareLoggingCategory.html

Examples:
org.kde.attica
org.kde.pim.kcalcore
kf5.kconfig.core
kf5.kconfigwidgets
sonnet.core
sonnet.plugins.aspell
kf5.kemoticons.plugin_adium

As a result one cannot "calculate" the name which would be used for a given 
library (or feature), but has to first look that up (or relying on 
kdebugsettings & maintained .categories file). Also am I missing the ability 
from KDebug times where there was the option to control debug output per 
certain feature across libraries/KF modules.

My proposal would be to switch to use these patterns:

    "kf".<module>[.<library>][.<internalfeature>]
    "kf".<module>.<type-of-plugins>.<plugin>[.<internalfeature>]
    "kf".<module>.<demon/tool>[.<internalfeature>]
    "kf".<module>.<publicfeature>[.<othercode>]

So the examples would become:
kf.attica
kf.calendarcore
kf.config.core
kf.configwidgets
kf.sonnet.core
kf.sonnet.clients.aspell
kf.emoticons.adium

If people agree on such standardization, I would propose to do that renaming 
already now and not only at KF6 time. Given the categories being rather 
undocumented, usually only looked up when needed and kdebugsettings also 
supporting renames, I would think we can improve the situation already now.
Having clear and known categories also might help once reaching work on KF6, 
when logged debugging might be more used during the Qt6 porting and other 5->6 
work.


Please head over to
	https://phabricator.kde.org/T12716
for a detailed description and reasoning of the current proposal to the 
problem, and join the discussion over there, so we have a central place to 
collect and track comments/ideas/work.

Cheers
Friedrich