Without network, gnome-software does not list installed snap packages

[Jean-Baptiste Lallement]

Test Case:
1. Without network (link down or behind a captive portal) go the installed packages tab and search for an installed snap

Expected result
Installed snaps should be listed and be removed

Actual result
No snap is listed. Furthermore, they are still not listed when network comes back and a restart of gnome-software is required.

ProblemType: Bug
DistroRelease: Ubuntu 17.10
Package: gnome-software 3.26.0-0ubuntu3
ProcVersionSignature: Ubuntu 4.13.0-12.13-generic 4.13.3
Uname: Linux 4.13.0-12-generic x86_64
ApportVersion: 2.20.7-0ubuntu2
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Mon Oct 9 15:02:37 2017
InstallationDate: Installed on 2013-09-03 (1496 days ago)
InstallationMedia: Ubuntu 13.10 "Saucy Salamander" - Alpha amd64 (20130902)
InstalledPlugins:
 gnome-software-plugin-flatpak N/A
 gnome-software-plugin-limba N/A
 gnome-software-plugin-snap 3.26.0-0ubuntu3
ProcEnviron:
 TERM=screen-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=fr_FR.UTF-8
 SHELL=/bin/bash
SourcePackage: gnome-software
UpgradeStatus: No upgrade log present (probably fresh install)

[Robert Ancell (robert-ancell)]

They're not listed because we fail to get icons for them (almost not snaps provide a local icon and we get them from the store - not available without network). GNOME Software doesn't allow apps without icons (an upstream decision, and not ideal for our case).

We do provide a default icon for snaps, but for some reason it seems to have stopped working. So one solution is to fix why that is. Another solution is to cache the store icon information (we already cache the icon data) so that it is still usable when office. I believe the snap team is also planning to cache store information locally, which will be a better long term fix for this.

[Robert Ancell (robert-ancell)]

The reconnection issue is part of a wider problem we have that snapd doesn't provide any notifications of changes and GNOME Software doesn't consider network status to affect the app information. We probably need to do some workarounds in GNOME Software for this and again snapd might better handle this long term.