phoebus: provide a settings.ini as template in the package

[vnadot]

Phoebus is most of the time started with the -settings $path_to_settings. It would be nice if the software package could contain a settings.ini example so we can easily use it to create our own one. This would be really useful when you don't have internet.

[Synthetica9]

Ideally we'd have free-form phoebus settings and a programs.phoebus.enable nixos setting

[minijackson]

We'd love to have a programs.phoebus.settings NixOS options, but there's a catch. Phoebus remembers settings, so if we apply:

org.phoebus.applications.alarm/server = my-alarm-server

Then launch Phoebus, then comment the setting:

#org.phoebus.applications.alarm/server = my-alarm-server

The setting will not revert back to its default value, and will still point to my-alarm-server. This is very confusing, and quite different from how other config files work.

We're looking with some Phoebus contributor colleagues if there's a possible fix or workaround (@katysaintin, @lcaouen)

[minijackson]

So @lcaouen asked around to see if there was a way to not save / load saved settings. Georg Weiss was very helpful in pointing us to the --clean argument, which removes all settings.

However, this also means that restarting Phoebus doesn't restore the previous session…

[minijackson]

Note: in the next release of Phoebus, the issue should be gone and we'll be able to have a programs.phoebus set of option without having to clear the previous session.

Let's wait for the next Phoebus release, then.