System-wide gsettings override do not work in gnome3

[dasj19]

Describe the bug
I just installed nixos unstable in a virtual machine and I was fiddling with configuration.nix
And whenever I try to set
services.xserver.desktopManager.gnome3.extraGSettingsOverrides values they do not get applied at all

To Reproduce
Steps to reproduce the behavior:
0. Get the value of gsettings get org.gnome.desktop.input-source sources to compare it to the updated one later.

1. Add the following to configuration.nix

services.xserver.desktopManager.gnome3.extraGSettingsOverrides = ''
  [org.gnome.desktop.input-source]
  sources=[('xkb','es'), ('xkb', 'ro')]
'';

2. nixos-rebuild switch
3. Notice that the value of gsettings get org.gnome.desktop.input-source sources is the same as before

Expected behavior
gsettings value to change for the entire system.

Additional context
I am trying to make available multiple keyboard layouts within gnome for the entire system.

Running gsettings set org.gnome.desktop.input-sources sources "[('xkb', 'es'), ('xkb', 'ro')]" manually as the user i logged in in gnome3 works fine.
When running the same command as root user I get the following error:
(process:10981): dconf-WARNING **: 08:46:30.177: failed to commit changes to dconf: Error spawning command line “dbus-launch --autolaunch=a76d5ca823e24f30b8988dd6683568bb --binary-syntax --close-stderr”: Child process exited with code 1
When I run the same command as root user over ssh it succeds.

Metadata

• system: "x86_64-linux"
• host os: Linux 4.19.66, NixOS, 19.09pre188498.4557b9f1f50 (Loris)
• multi-user?: yes
• sandbox: yes
• version: nix-env (Nix) 2.2.2
• nixpkgs: /nix/var/nix/profiles/per-user/root/channels/nixos

Maintainer information:

# a list of nixpkgs attributes affected by the problem
attribute:
# a list of nixos modules affected by the problem
module:

[worldofpeace]

cc @jtojnar

[jtojnar]

extraGSettingsOverrides option relies on GSettings overrides mechanism, therefore only overrides default values. Once a configuration value is set, the value declared in extraGSettingsOverrides no longer applies.

gnome-settings-daemon reads the default value of org.gnome.desktop.input-source.sources listed in the schema and sets the current value to that when no value is set in the configuration database at login.

If you call gsettings reset org.gnome.desktop.input-sources sources and re-login, you will get the correct language settings.

For a proper configuration, we need #54150.

As for the root user, GSettings use dconf backend by default, which needs D-Bus. Though, it probably does not make sense to try to set the setting, as you are not supposed to run graphical environment as root.

[stale]

Thank you for your contributions.

This has been automatically marked as stale because it has had no activity for 180 days.

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[variadico]

I ran into this myself.

And a quick look at Discourse shows others too:
https://discourse.nixos.org/t/gnome3-settings-via-configuration-nix/5121

services.xserver.desktopManager.gnome3.extraGSettingsOverrides = ''
[org.gnome.desktop.background]
picture-uri='file://home/alexey/my-background.jpg'
'';

[jtojnar]

Nothing changed from above. Since the option can only change the defaults, you need to clear the current value of the setting from the configuration database using dconf reset /org/gnome/desktop/background/picture-uri for the default to be used.

For a proper configuration, we need #54150.

[stale]

I marked this as stale due to inactivity. → More info