update-manager should recommend not depend on ubuntu-advantage-tools

[Max]

During latest update of Ubuntu-20.04 focal the following conflict appeared: either ubuntu-advantage-tools must be installed or ttf-mscorefonts-installer must be removed. Such dependence should not be hard, I do not mind (indirect) "recommends" relation.

Since I have no intention to subscribe to ESM or to kernel live patch (sorry, I am not a source of profit for Canonical, at least direct one), I removed ubuntu-advantage-tools and it was working smoothly till the last update.

    apt upgrade

attempted to install new package ubuntu-advantage-tools. I tried to set `Pin-Priority: -1` to this package (I do not recommend such recipe, so no config snippet here). The result is:

    The following packages have been kept back:
      python3-update-manager

I do not expect upgrade till next year, so I tried to remove packages necessary for dist-upgrade

    apt purge update-manager-core
    The following packages will be REMOVED:
      ttf-mscorefonts-installer* update-manager-core* update-notifier-common*

Removing of ttf-mscorefonts-installer is against my goal. I would prefer to keep the fonts.

1. ttf-mscorefonts-installer should not depend on update-notifier-common. I noticed /var/lib/update-notifier/package-data-downloads/ directory in /var/lib/dpkg/info/ttf-mscorefonts-installer.postinst If it is the only reason of dependency, the package may create the directory itself.

2. I hope, there is a way to avoid stale ubutu-advantage-tools without hard dependency in update-manager-core (e.g. "recommends" and some conflicts to earlier versions).

I do not know the full story, I found lp:1926361, but fixes released several months ago. I have no idea why the problem appeared on my machine this week.

It seems, there 2 independent issues that are quite harmless while isolated but their combination causes a problem. Please, disentangle ttf-mscorefonts-installer and ubuntu-advantage-tools.

[Julian Andres Klode (juliank)]

WRT mscorefonts depending on update-notifier-common, this is necessary, update-notifier-common has centralized downloading of addons like htis.

[Paride Legovini (paride)]

Hello Max and thanks for this bug report.

I don't think there's anything that could be done about this on the ubuntu-advantage-tools side, as the dependency is in the other direction, so I'm marking the u-a-t task as Invalid.

I had a look at the update-manager-core and at first glance it seems to me that the current implementation of the check for UA being enabled should handle ua being absent, so the Depends *could* maybe be relaxed to a Recommends, with extra care. In any case this is almost certainly not SRU material.

[Max (m-gorodok)]

Paride Legovini (paride) wrote in comment #2
> In any case this is almost certainly not SRU material.

I added ubuntu-advantage-tools package to this bug expecting pressure from that side to issue an urgent update of update-manager-core to LTS. It is sour that dependency added in *LTS update* can not be corrected to a more flexible value in a following update.

Julian Andres Klode (juliank) wrote in comment #1
> WRT mscorefonts depending on update-notifier-common, this is necessary

I am going to try whether installing a package from Debian may be a workaround. Anyway updates of mscorefonts are unlikely.
https://packages.debian.org/bullseye/ttf-mscorefonts-installer

[Max (m-gorodok)]

A workaround applicable for LTS:

apt install equivs

create ubuntu-advantage-tools-dummy.equivs file:
---- >8 ----
Package: ubuntu-advantage-tools
Version: 99:99
Maintainer: Your Name <email address hidden>
Architecture: all
Description: Dummy ubuntu-advantage-tools replacement.
 Workaround for lp:1945794
---- 8< ----

equivs-build ubuntu-advantage-tools-dummy.equivs
dpkg -i ubuntu-advantage-tools_99_all.deb

[Launchpad Janitor (janitor)]

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