Allow setting sdwdate gateway via qvm-features/qvm-prefs

[mzpqnxow]

I'm not sure if this should be seriously considered as it's a pretty niche use-case

However, there is a documented manual process for this so maybe it should be considered as something users need more hand holding on

The problem you're addressing (if any)

When a user renames the sys-whonix qube or has multiple Whonix Gateways - basically, any time a user uses a Whomix Gateway that is not named sys-whonix - they must manually update sdwdate settings as described here

The steps aren't hard once it's clear that they're necessary

The file /usr/local/etc/sdwdate-gui.d/50_user.conf must be created like so:

sudo mkdir -p /usr/local/etc/sdwdate-gui.d && echo "gateway=<whonix gateway vm name>" | sudo tee /usr/local/etc/sdwdate-gui.d/50_user.conf

If I understand correctly this (at least) allows the sdwdate GUI in the dom0 taskbar to work properly. It may have a more substantial impact as well, I'm not too knowledgeable about Whonix Gateway/Workstation so I'm not certain

This step is easy to automate and impossible to forget if it's being built using salt, but otherwise it's both clunky, obscure and easy to forget. It's not obvious that it's even "a thing" unless you explicitly look into Qubes forums or the linked Whonix docs for this specific configuration

The solution you'd like

To make it easier, it would be nice if there was a way to set this value without manually editing the AppVM. Perhaps this could be done via qvm-prefs?

It would also be nice to have some mechanism to notify the user that they need to take this step. This could be some sort of blocking behavior when the gateway starts or (at least) some warning. I don't know a way to do either of these so I can't propose an elegant or reliable way

The value to a user, and who that user might be

It would save users who experiment with multiple whonix gateways or rename sys-whonix time trying to diagnose "weird" or broken behavior

Completion criteria checklist