Backup and restore /etc/products.d (bsc#1219004)

[rtamalin]

The Distribution Migration System (DMS) implements a non-interactive
fully automated offline migration of systems by booting into a ISO
image that runs through the migration. In some cases, if a migration
from one product stream to another product stream fails, the normal
rollback handling doesn't always restore the products state correctly.

To address this we should include the /etc/products.d contents in the
backup that is created and restored.

Add changelog entry for upcoming v1.9.0 release stream, including the
bug tracking id.

Add unit test for the zypper Backup and Restore routines.

Also fixed two bugs found while developing the unit test:

• CreateTarball()'s check for potential tar arguments incorrectly
  checked under the local file system hierarchy, rather than under
  the specified root hierarchy, meaning it could skip backing up
  entries that might exist under the root if they didn't exist
  locally.

• The /var/adm/backup/system-upgrade directory created under the
  specified root hierarchy, and missing intermediary directories,
  were being created with no access permissions, meaning that only
  a privileged superuser could access them. In reality migrations
  are run as root so it didn't impact customer usage, but it did
  cause problems for the unit tests running as a non-privileged
  user.

Fixes: #231, #232

Co-authored-by: Felix Schnizlein [email protected]

[rtamalin]

During a migration I see that the templated repos.sh restore script has been updated to include the etc/products.d:

migration@localhost:~> sudo cat /system-root/var/adm/backup/system-upgrade/repos.sh 
#! /bin/sh
# change root to first parameter or use / as default
# it is needed to allow restore in installation
cd ${1:-/}
rm -rf etc/zypp/repos.d
rm -rf etc/zypp/credentials.d
rm -rf etc/zypp/services.d
rm -rf etc/products.d

tar xvf var/adm/backup/system-upgrade/repos.tar.gz --overwrite
# return back to original dir
cd -

Similarly the restore tarball includes the etc/products.d files:

...
drwxr-xr-x root/root         0 2024-04-29 16:51 etc/products.d/
lrwxrwxrwx root/root         0 2024-03-04 14:21 etc/products.d/baseproduct -> SLES_SAP.prod
-rw-r--r-- root/root      2937 2024-04-29 18:28 etc/products.d/SLES_SAP.prod
-rw-r--r-- root/root      2049 2017-11-23 10:28 etc/products.d/sle-module-public-cloud.prod
-rw-r--r-- root/root      2145 2019-10-18 19:21 etc/products.d/sle-module-legacy.prod
-rw-r--r-- root/root      2254 2017-11-23 10:48 etc/products.d/sle-module-web-scripting.prod
-rw-r--r-- root/root      2054 2017-11-23 10:25 etc/products.d/sle-module-adv-systems-management.prod
-rw-r--r-- root/root      1577 2019-08-29 10:03 etc/products.d/sle-module-containers.prod
-rw-r--r-- root/root      1814 2016-12-07 12:35 etc/products.d/sle-module-toolchain.prod
-rw-r--r-- root/root      2029 2017-04-20 23:14 etc/products.d/sle-module-hpc.prod
-rw-r--r-- root/root      2363 2019-10-18 11:58 etc/products.d/sle-sdk.prod
-rw-r--r-- root/root      1920 2019-09-02 10:54 etc/products.d/PackageHub.prod

[felixsch]

Can you please provide a test case how to test this change? Should be easy I assume but we have our internal ruling to try to provide at least one test case per pull request :)

[rtamalin]

Can you please provide a test case how to test this change? Should be easy I assume but we have our internal ruling to try to provide at least one test case per pull request :)

Do you mean a feature test or a unit test? There don't appear to be existing unit or feature tests for backup or restore, though I may not be grokking things in the Ruby testing stuff properly...

[felixsch]

lgtm 👍

How I reviewed this pull request:

• Ran a migration from 15.3 to 15.5 and checked that both:
  • /var/adm/backup/system-upgrade/repos.sh
  • /var/adm/backup/system-upgrade/repos.tar.gz exist
• Checked that repos.sh includes products.d directory
• Checked that repos.tar.gz includes products.d/ directory content
• Let the migration rollback and check that everything as been reset

As always, if you think I missed something I should test, please let me know!🚀