Adding broken PPA doesn't show it or report an error

[Gary Lasker]

(This bug may be masked by bug 782953, where even non-broken PPAs don't appear when added.)

software-center version 2.0.2

After attempting to add a PPA using Edit->Software Sources..., the PPA did not appear in the navigation tree in the left panel and no error indication of any kind was displayed. It appears that the PPA was exhibiting some kind of authentication problem that caused it not to be added. Unfortunately, I can no longer reproduce this as the failing PPA has since been deleted.

By all indications it appears to have been a rare condition that caused this as we've had no other reports to date of a problem of this type. Nevertheless, we should make sure we handle this kind of error if it occurs. Even just a simple error dialog would probably suffice to let the user know a problem was detected with the PPA being added.

For the record, the failing PPA was ppa:nisshh/ppa. It contained a single package: pytask.

[Gary Lasker (gary-lasker)]

Here's the output when launching software-center from the command line. The key processing output occurs immediately after adding the source:

$ software-center
/usr/share/software-center/softwarecenter/apt/aptcache.py:40: GtkWarning: gtk_container_add: assertion `GTK_IS_CONTAINER (container)' failed
  gtk.main_iteration()
Executing: gpg --ignore-time-conflict --no-options --no-default-keyring --secret-keyring /etc/apt/secring.gpg --trustdb-name /etc/apt/trustdb.gpg --keyring /etc/apt/trusted.gpg --primary-keyring /etc/apt/trusted.gpg --keyserver keyserver.ubuntu.com --recv 58D821F29320562A8CA853F293D6696927F02699
gpg: Total number processed: 1
gpg: unchanged: 1

[Gary Lasker (gary-lasker)]

After adding the source, the package in the PPA is visible as shown:

$ apt-cache policy pytask
pytask:
  Installed: (none)
  Candidate: 0.3.0-public1
  Version table:
     0.3.0-public1 0
        500 http://ppa.launchpad.net/nisshh/ppa/ubuntu/ lucid/main Packages

However, attempting to install the package shows the following auth warning:

$ sudo apt-get install pytask
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
  intel-gpu-tools
Use 'apt-get autoremove' to remove them.
The following NEW packages will be installed:
  pytask
0 upgraded, 1 newly installed, 0 to remove and 13 not upgraded.
Need to get 24.5kB of archives.
After this operation, 197kB of additional disk space will be used.
WARNING: The following packages cannot be authenticated!
  pytask
Install these packages without verification [y/N]?

[Gary Lasker (gary-lasker)]

I did notice a problem with the files in /var/lib/apt/lists that correspond to the broken PPA. A working PPA will have three files in this directory as shown:

ppa.launchpad.net_docky-core_ppa_ubuntu_dists_lucid_main_binary-i386_Packages
ppa.launchpad.net_docky-core_ppa_ubuntu_dists_lucid_Release
ppa.launchpad.net_docky-core_ppa_ubuntu_dists_lucid_Release.gpg

However, the broken PPA had only the single file:

ppa.launchpad.net_nisshh_ppa_ubuntu_dists_lucid_main_binary-i386_Packages