Developer setups for user D-Bus service files?

[Friedrich W. H. Kossebau]

Am Dienstag, 11. Januar 2022, 22:49:47 CET schrieb David Edmundson:
> >at least with systemd controlled start (but possibly also before
> 
> Since forever.

Okay, guessed so, as I had found decade old queries trying to solve similar 
challenges, though systemd also is that age, thus was not that sure :)

> >So, what standard approach should we take as developers here?
> 
> Personally I would say developers should avoid having a system
> installed KDE, you're only making life harder for yourself.

And for other users on the system (even one one's "safe" user account) which 
would like to only run released and packaged software :)

> For systemd services...

Myself not yet into systemd services, currently only trying to get D-Bus 
services working for user-local installs, but I guess this is related on 
systemd systems?

> ----
> I did start another idea.
> 
> If you populate the dev session environment variables *really* early
> must we even go through pam you can set your XDG_DATA_DIRS before DBus
> daemon has loaded it will then have the right stuff.
> I made a patch doing that: https://github.com/sddm/sddm/pull/1370
> which is merged but not released:

Is this something that could be achieved also by editing whatever config files 
for now? And again in a way that it only is applied for a certain user 
account?
Those X-SDDM-Env entries, they though also would be only global, so I would 
need a separate workspace session config file, which then appears also for 
everyone else as option on login, right? Not ideal for shared systems. And 
also not perfect for a system where a user just wants their custom-made 
utility software to run in their user account on the provided company 
computer, like person working in a lab.

FWIW, I was hoping there was a way to add some entries to the D-Bus config 
files, which would add a <servicedir> only for a certain user, or perhaps even 
an <include> only done for a certain user (perhaps relying on 
ignore_missing=yes).
But I found no such condition, and the <include> tags only works with final 
strings by what I saw in the code, no variable substitution (doc/busconfig.dtd 
is undocumented, boo).

Cheers
Friedrich