gnome-software cannot install classic snaps if a channel is selected

[fcole90]

I tried installing Android Studio from gnome-software. In the top right dropdown, it asks for the source. For Andoid Studio it displays Ubuntu. I was suspicious of it being a deb and not a snap. So I clicked on it and it shown me 3 Snap channel options. I selected latest/stable. The source changed according to my selection. Then I tried installing it but it failed saying:

Unable to install "Android Studio": snap "android-studio" requires classic confinement

I was puzzled. So I went back to the search menu, I clicked again on Android Studio and the source was now again on Ubuntu (note that this is not an option available in the dropdown). I checked the details and indeed it's the snap package from channel latest/stable, just the source is somehow misleading. Now it installed the software without issues.

What doesn't work:
- Source dropdown (top-right) shows "Ubuntu" instead of the snap channel
- Selecting a channel breaks the install functionality for classic snaps (it seems like it attempts to install them without --classic)

Workaround:
Do not select any channel, just use what is provided, and it works. If needing to use a different channel, use the command line (or perhaps check if this works in the Snap Store, if it has not the same issue).

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: gnome-software 3.36.0-0ubuntu3
ProcVersionSignature: Ubuntu 5.4.0-28.32-generic 5.4.30
Uname: Linux 5.4.0-28-generic x86_64
ApportVersion: 2.20.11-0ubuntu27
Architecture: amd64
CasperMD5CheckResult: skip
CurrentDesktop: GNOME
Date: Tue May 5 11:09:26 2020
InstallationDate: Installed on 2020-04-03 (31 days ago)
InstallationMedia: Ubuntu 20.04 LTS "Focal Fossa" - Beta amd64 (20200401)
InstalledPlugins:
 gnome-software-plugin-flatpak 3.36.0-0ubuntu3
 gnome-software-plugin-snap 3.36.0-0ubuntu3
SourcePackage: gnome-software
UpgradeStatus: No upgrade log present (probably fresh install)
modified.conffile..etc.apport.crashdb.conf: [modified]
mtime.conffile..etc.apport.crashdb.conf: 2020-05-04T10:26:46.106768

[Sebastien Bacher (seb128)]

Confirmed on focal

- open snap-store
- search for android
- click on android studio
- click on the top right selector
- click on the already select stable to close the popdown
- select install

-> the installation fail

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Tony Thuitai (tonythuitai-deactivatedaccount)]

Bug also occurs on gnome software in groovy

[FelipeAF (felipealexandref)]

Here often gnome software cannot update Gitkraken snap, it shows an error message that Gitkraken uses classic confinement.

[Danilo Alculete (alculete)]

I have the same bug

[Robert Ancell (robert-ancell)]

The cause is `gs_plugin_add_alternates` doesn't set the `snap::confinement` metadata item, so the channels other than the default aren't detected as classic.

[Robert Ancell (robert-ancell)]

https://gitlab.gnome.org/GNOME/gnome-software/-/merge_requests/577
https://gitlab.gnome.org/Community/Ubuntu/gnome-software/-/merge_requests/33

[Ken VanDine (ken-vandine)]

This is now fixed in the stable channel.