Background portal

[joshuamegnauth54]

Requires the access portal to be enabled or else it does nothing

I based my implementation on the official specs as well as code from GNOME, KDE, Xapp (Xfce), and Pantheon (elementary). KDE's immaculately readable codebase served as this implementation's primary inspiration.

Like KDE, I intend to show a dialog, so the user may choose whether to grant privileges to an application. I will also provide an option to bypass the dialog for greater choice especially considering that GNOME automatically grants permissions.

According to the docs, the Autostart method is deprecated. However, I think I still need to implement it because background requests aren't routed to the COSMIC portal unless it's available. Autostart is implemented

Closes: #49

[ids1024]

According to the docs, the Autostart method is deprecated. However, I think I still need to implement it because background requests aren't routed to the COSMIC portal unless it's available.

Looks like it was deprecated in May (flatpak/xdg-desktop-portal@458560c) and the last release was in April. So presumably it's still required on released versions of xdg-desktop-portal, but won't in the next.

[joshuamegnauth54]

Their reasoning makes sense. Every portal backend I checked implements autostart the same way (which, in a way, was really nice because it made it easier to implement here 😂 ).

This is finally done and it works too! I learned a lot in the process as well.

[Drakulix]

I don't think this is right. A toplevel is a window, this state seems to describe applications without a window. So the logic should be: If any toplevel exists, then the app is either Running or Active. We currently don't have a protocol to enumerate applications without a window.

I would think the portal would have to track apps launched in the background.

[joshuamegnauth54]

Thanks for the review and help!

I checked how GNOME handles GetAppState. GNOME exposes a D-Bus interface that allows retrieving the list of running applications. It also has a signal for app updates.

Its Background portal uses that interface to check app statuses. An app that is running without windows is in the background. Apps with windows have their toplevel status checked (active, running).

KDE doesn't seem to check if a program is in the background at all. 🤔 I find this confusing.

The code for the GNOME background portal is pretty straightforward, but I'll have to check if there is a way to get running apps easily via COSMIC.

[Drakulix]

There isn't because we don't track "running applications" (which KDE probably also isn't doing), because doing so isn't exactly easy. Any running binary could be an "app".

I assume what Gnome is doing internally is:

1. Handle flatpaks as apps
2. Use app-scopes to identify apps it launched through one of it's interfaces (still doesn't help with stuff started e.g. via a terminal).

You can do similar things on cosmic, as we also set the corresponding app-scopes. (e.g. systemctl --user list-units -t scope | grep -e "app-flatpak" -e "app-cosmic")

You would use the systemd dbus interface in the portal to enumerate the scopes, filter for app-cosmic and app-flatpak and pull the app_id from the name (the third component). Afterwards you can lookup the desktop-file, if you need anything more.