The cause appears to be multiple threads accessing the same SnapdClient object at the same time. This causes multiple requests to be sent at the same time and snapd-glib has a bug that doesn't handle the replies correctly. The solution in bug 1718170 is to make a SnapdClient for each thread, and avoids this issue.
-- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gnome-software in Ubuntu. https://bugs.launchpad.net/bugs/1721740 Title: Impossible to install snap: Unexpected change ID returned Status in gnome-software package in Ubuntu: Triaged Bug description: with core 16-2.28.1 from candidate Test Case 1. In gnome-software install a snap 2. When the polkit auth dialog shows up do nothing and wait for at least 5 minutes 3. After 5 minutes,, type your password and proceed with the installation Actual result The installation fails with this message: "Impossible to install snap: Unexpected change ID returned" Expected result Installation is successful 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: Fri Oct 6 12:19:23 2017 InstallationDate: Installed on 2014-07-23 (1170 days ago) InstallationMedia: Ubuntu 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.2) 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: Upgraded to artful on 2017-06-13 (114 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-software/+bug/1721740/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp

