Launching ua status → An unexpected error occurred: list index out of range

[Marco Trevisan (Treviño)]

[ Impact ]

If `apt` is masked by other helper tools, such as `nala`, as seen in the original description, `apt list --installed` will return data in a different format. This will cause the Pro Client to fail to parse the data, and break.

The Pro Client should not be relying on CLI output when there are Python bindings available to perform the same task - and python3-apt provides ways to list installed packages.

The fix to this bug is to rely on the programmatic integration with APT instead of calling the CLI.

[ Test Plan ]

Listing installed packages is part of the regular operation of the Pro Client in many scenarios covered by the integration / acceptance tests.

For this particular issue:
- Launch a container for the release to be tested
- install nala
- alias `apt` to `nala` in the system
- see it fail
- install the package from -proposed
- see it does not fail anymore

[ Where problems could occur ]

Switching from the CLI call to python3-apt brings the risk of wrong implementation of the integration, which would lead to a different package list to be returned by python3-apt. The regression potential is mitigated by extensive testing - unit, integration and acceptance tests rely on this functionality.

[ Original description ]

This is in 22.04

❯ ua status
An unexpected error occurred: list index out of range
For more details, see the log: /home/marco/.cache/ubuntu-pro/ubuntu-pro.log
If you think this is a bug, please run: ubuntu-bug ubuntu-advantage-tools

ProblemType: Bug
DistroRelease: Ubuntu 22.04
Package: ubuntu-advantage-tools 31.2.3~22.04
ProcVersionSignature: Ubuntu 6.8.0-35.35-generic 6.8.4
Uname: Linux 6.8.0-35-generic x86_64
ApportVersion: 2.20.11-0ubuntu82.5
Architecture: amd64
CasperMD5CheckResult: unknown
CurrentDesktop: ubuntu:GNOME
Date: Fri Jun 7 17:42:12 2024
InstallationDate: Installed on 2010-07-10 (5081 days ago)
InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release amd64 (20100429)
PackageArchitecture: all
RebootRequiredPkgs: Error: path contained symlinks.
SourcePackage: ubuntu-advantage-tools
UpgradeStatus: Upgraded to jammy on 2020-06-14 (1453 days ago)
cloud-id.txt-error: Invalid command specified 'cloud-id'.
jobs-status.json: {"metering": {"last_run": "2024-06-07T15:40:15.416242+00:00", "next_run": "2024-06-07T19:40:15.416242+00:00"}, "update_contract_info": null, "update_messaging": {"last_run": "2024-06-07T15:40:15.416242+00:00", "next_run": "2024-06-07T21:40:15.416242+00:00"}}
uaclient.conf:
 contract_url: https://contracts.canonical.com
 log_level: debug

[Renan Rodrigo (renanrodrigo)]

Hi Marco, thanks for reporting this

The parsing of `apt list --installed` is failing - we are trying to extract version information using the pattern, and it fails.

The root cause fix will be deployed next release. But to know what is happening here, could you please append the output of `apt list --installed`? Thanks

[Marco Trevisan (Treviño) (3v1n0)]

Oh... So, that's probably my local fault since I've a local script that overrides `apt` in my path so that I actually end up the nicer `nala` apt UI frontend...

So, I've fixed this locally.

However, I feel that it would be nicer if instead of calling apt, you should probably use always /usr/bin/apt, or even better use the python3-apt bindings instead of parsing apt results

[Renan Rodrigo (renanrodrigo)]

Nice! We have switched to python3-apt recently, and this will be not a problem anymore in v33.

[Launchpad Janitor (janitor)]

This bug was fixed in the package ubuntu-advantage-tools - 33

---------------
ubuntu-advantage-tools (33) oracular; urgency=medium

  * d/apparmor: adjust the esm_cache apparmor profile to allow reading of dpkg
    data directory (LP: #2067810) (GH: #3137)
  * New upstream release 33 (LP: #2069237)
    - apt: use Python bindings instead of apt CLI to query for installed
      packages (LP: #2060769) (LP: #2068744)
    - beta: drop support for beta services
    - contracts: add support for contracts which target a specific series
    - fips: change enable functionality to ensure all packages with a FIPS
      candidate are upgraded to the FIPS version (GH: #2667)
    - fix:
      + add the current_status field to the plan api return object
      + change recommended attach method to magic attach (GH: #3040)
    - livepatch: prefer the term 'coverage' instead of 'support' in messaging
      (GH: #3063)
    - realtime:
      + auto-select the raspi variant when appropriate
      + inform the user when auto-selecting a variant

 -- Renan Rodrigo <email address hidden> Thu, 13 Jun 2024 00:19:54 -0300

[Robie Basak (racb)]

Hello Marco, or anyone else affected,

Accepted ubuntu-advantage-tools into noble-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/ubuntu-advantage-tools/33~24.04 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, what testing has been performed on the package and change the tag from verification-needed-noble to verification-done-noble. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-noble. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

[Robie Basak (racb)]

Hello Marco, or anyone else affected,

Accepted ubuntu-advantage-tools into jammy-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/ubuntu-advantage-tools/33~22.04 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, what testing has been performed on the package and change the tag from verification-needed-jammy to verification-done-jammy. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-jammy. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

[Robie Basak (racb)]

Hello Marco, or anyone else affected,

Accepted ubuntu-advantage-tools into focal-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/ubuntu-advantage-tools/33~20.04 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, what testing has been performed on the package and change the tag from verification-needed-focal to verification-done-focal. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-focal. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

[Robie Basak (racb)]

Hello Marco, or anyone else affected,

Accepted ubuntu-advantage-tools into bionic-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/ubuntu-advantage-tools/33~18.04 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, what testing has been performed on the package and change the tag from verification-needed-bionic to verification-done-bionic. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-bionic. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

[Robie Basak (racb)]

Hello Marco, or anyone else affected,

Accepted ubuntu-advantage-tools into xenial-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/ubuntu-advantage-tools/33~16.04 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, what testing has been performed on the package and change the tag from verification-needed-xenial to verification-done-xenial. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-xenial. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.