missing version dependency on distro-info

[James Troup]

[Impact]

If a user on xenial or on bionic has an old version of distro-info and then upgraded ubuntu-advantage-tools, they will get periodic tracebacks from our update_messaging systemd unit, and enabling services with ua will always fail.

The fix is to specify the required versions of distro-info that ubuntu-advantage-tools needs to function.

Backporting this fix is necessary to ensure xenial and bionic users who happen to have an older version of distro-info are able to enable ubuntu-advantage services without first finding this bug, then manually upgrading distro-info.

[Test Plan]

This should be tested on both xenial and bionic. These test steps assume that the proposed version of ua to release is available in ppa:ua-client/staging - check with the ubuntu-advantage-tools team before proceeding to make sure this is the case.

First reproduce the issue.

In a xenial container:
```
sudo apt install distro-info=0.14build1 distro-info-data=0.28
sudo apt install ubuntu-advantage-tools
sudo python3 /usr/lib/ubuntu-advantage/ua_update_messaging.py
# expect a traceback
sudo ua attach YOUR_TOKEN
# expect error messages
sudo ua detach
# expect error messages
```

In a bionic container:
```
sudo apt install distro-info=0.18 distro-info-data=0.37
sudo apt install ubuntu-advantage-tools
sudo python3 /usr/lib/ubuntu-advantage/ua_update_messaging.py
# expect a traceback
sudo ua attach YOUR_TOKEN
# expect error messages
sudo ua detach
# expect error messages
```

To see the fix in action, on both xenial and bionic:
```
sudo add-apt-repository ppa:ua-client/staging
sudo apt-get update
sudo apt install ubuntu-advantage-tools
sudo python3 /usr/lib/ubuntu-advantage/ua_update_messaging.py
# there should be no traceback or error
sudo ua attach YOUR_TOKEN
# expect success and no error messages
sudo ua detach
# expect success and no error messages
```

[Where problems could occur]

In order to require the correct versions for both xenial and bionic and later releases, the Depends line is somewhat complex. The same line is required under Build-Depends as well. So if there is a mistake, such as if the version constraints incorrectly include a version they shouldn't, then this could cause errors during build as well as during install.

[Other Info]

The complexity in the depends line is because of the following versions of distro-info. This list includes which release they are one and which ones will work as our dependency:

- xenial: 0.14build1 doesn't work
- xenial: 0.14ubuntu0.2 works
- bionic: 0.18 doesn't work
- bionic: 0.18ubuntu0.18.04.1 works

focal and later have higher version numbers than 0.18

So to grab the correct version across all versions, we need to set a minumum version of 0.18ubuntu0.18.04.1 OR get exactly 0.14ubuntu0.2, but nothing in between.

[Original Description]

27.0~16.04.1 on Xenial. ubuntu-advantage-tools was upgraded, the rest of the machine is painfully behind.

Resulted in this:

Jun 15 13:34:46 MAAS systemd[1]: Starting Ubuntu Advantage APT and MOTD Messages...
Jun 15 13:34:46 MAAS python3[15434]: Traceback (most recent call last):
Jun 15 13:34:46 MAAS python3[15434]: File "/usr/lib/ubuntu-advantage/ua_update_messaging.py", line 302, in <module>
Jun 15 13:34:46 MAAS python3[15434]: update_apt_and_motd_messages(cfg=cfg)
Jun 15 13:34:46 MAAS python3[15434]: File "/usr/lib/ubuntu-advantage/ua_update_messaging.py", line 284, in update_apt_and_motd_messages
Jun 15 13:34:46 MAAS python3[15434]: if not util.is_lts(series):
Jun 15 13:34:46 MAAS python3[15434]: File "/usr/lib/python3/dist-packages/uaclient/util.py", line 353, in is_lts
Jun 15 13:34:46 MAAS python3[15434]: out, _err = subp(["/usr/bin/ubuntu-distro-info", "--supported-esm"])
Jun 15 13:34:46 MAAS python3[15434]: File "/usr/lib/python3/dist-packages/uaclient/util.py", line 608, in subp
Jun 15 13:34:46 MAAS python3[15434]: out, err = _subp(args, rcs, capture, timeout, env=env)
Jun 15 13:34:46 MAAS python3[15434]: File "/usr/lib/python3/dist-packages/uaclient/util.py", line 565, in _subp
Jun 15 13:34:46 MAAS python3[15434]: stderr=err.decode("utf-8"),
Jun 15 13:34:46 MAAS python3[15434]: uaclient.util.ProcessExecutionError: Failed running command '/usr/bin/ubuntu-distro-info --supported-esm' [exit(1)]. Message: ubuntu-distro-info: unrecognized option `--supported-esm'
Jun 15 13:34:46 MAAS systemd[1]: ua-messaging.service: Main process exited, code=exited, status=1/FAILURE
Jun 15 13:34:46 MAAS systemd[1]: Failed to start Ubuntu Advantage APT and MOTD Messages.
Jun 15 13:34:46 MAAS systemd[1]: ua-messaging.service: Unit entered failed state.
Jun 15 13:34:46 MAAS systemd[1]: ua-messaging.service: Failed with result 'exit-code'.

Installed distro-info was 0.14build1 ; upgrading to current fixed it.

[Thiago Martins (martinx)]

Hi,

I also see this problem with fresh installed Xenial.

It's interesting to see that it's a bit tricky to reproduce this problem. I have to upgrade "ubuntu-advantage-tools" shortly after installing Xenial.

Cheers!

[Chad Smith (chad.smith)]

https://github.com/canonical/ubuntu-advantage-client/pull/1684 landed with proper explicit versioned dependencies distro-info defined. Expect to see this in ubuntu-advantage-tools v. 27.3.

Right on unique failure reproduce is a base original release of xenial with an immediate upgrade of ubuntu-advantage-tolls. If daily APT updates run first before the ua-tools upgrade, this should be resolved by the fact that the version of distro-info in xenial-updates or bionic-updates is sufficient enough that this doesn't pose a problem.

[Launchpad Janitor (janitor)]

This bug was fixed in the package ubuntu-advantage-tools - 27.2~21.10.1

---------------
ubuntu-advantage-tools (27.2~21.10.1) impish; urgency=medium

  * d/control:
    - add comments to explain complex build-depends
    - add version requirement to distro-info (LP: #1932028)
  * d/tools.postinst:
    - run status.json schema patch script to avoid non-root status errors
  * New upstream release 27.2:
    - attach: print contract server reason for 403 (GH: #1630)
    - cli: add ua config set, unset and show subcommands
    - config:
      + add default ua_config setting values
      + only allow some fields to be set by envvar
      + use defaults for contract and security url
    - docs:
      + add proxy config options to man page
      + add instructions to generate MOTD messages
      + add support matrix info
      + remove broken api link
    - enable: allow downgrading packages during enable (GH: #1659)
    - fips:
      + add focal test for fips-updates
      + alert if wrong fips package installed on gov clouds
      + install correct fips package on gov clouds
      + only install conditional_packages if necessary and available
    - logs: log env vars that affect config on cli runs
    - proxy:
      + add config options to set proxies
      + print message when setting proxy
      + support configuring apt proxies
      + support configuring snap and livepatch proxies
      + support setting proxy for web requests
      + validate urls before setting as proxies
    - refresh: support refreshing config and contract separately
    - status
      + add config info to json output
      + add env vars to json output
      + do not show unavailable services in json output
      + support yaml format with same content as json format
      + update account info in json output
      + update contract info in json output
      + update root level keys of json output
    - refactor:
      + remove side effects from can_enable (GH: #1654, #1571)
      + use DatetimeAwareJSONDecoder to parse date strings
    - tests:
      + add additional enable test for incompatible services
      + add flag to enable proposed pocket
      + add test to check and print version being tested
      + drop trusty specific tests

 -- Grant Orndorff <email address hidden> Fri, 09 Jul 2021 13:07:23 -0400

[Grant Orndorff (orndorffgrant)]

I have verified the version of ubuntu-advantage-tools in -proposed fixes this bug. The logs of my tests are attached here.

[Launchpad Janitor (janitor)]

This bug was fixed in the package ubuntu-advantage-tools - 27.2.1~21.04.1

---------------
ubuntu-advantage-tools (27.2.1~21.04.1) hirsute; urgency=medium

  * Backport new upstream release: (LP: #1934902) to hirsute

 -- Chad Smith <email address hidden> Fri, 16 Jul 2021 12:49:23 -0600

[Launchpad Janitor (janitor)]

This bug was fixed in the package ubuntu-advantage-tools - 27.2.1~20.04.1

---------------
ubuntu-advantage-tools (27.2.1~20.04.1) focal; urgency=medium

  * Backport new upstream release: (LP: #1934902) to focal

 -- Chad Smith <email address hidden> Fri, 16 Jul 2021 12:48:51 -0600

[Launchpad Janitor (janitor)]

This bug was fixed in the package ubuntu-advantage-tools - 27.2.1~18.04.1

---------------
ubuntu-advantage-tools (27.2.1~18.04.1) bionic; urgency=medium

  * Backport new upstream release: (LP: #1934902) to bionic

 -- Chad Smith <email address hidden> Fri, 16 Jul 2021 12:48:22 -0600

[Launchpad Janitor (janitor)]

This bug was fixed in the package ubuntu-advantage-tools - 27.2.1~16.04.1

---------------
ubuntu-advantage-tools (27.2.1~16.04.1) xenial; urgency=medium

  * Backport new upstream release: (LP: #1934902) to xenial

 -- Chad Smith <email address hidden> Fri, 16 Jul 2021 12:47:53 -0600