Add support for /home reuse to automatic partitioning

[rvykydal]

This is a draft, POC of an approach trying to follow the analysis by @poncovka and @vojtechtrefny which is linked in the https://issues.redhat.com/browse/INSTALLER-4020

It is extending autopartitioning (partitioning AUTOMATIC) with some mount point assignment (partitioning MANUAL) mechanisms.

Tested (supposed) to be working on all partitioning schemes (plain, btrfs, lvm, thinlv), reusing unencrypted autopart.

The idea is to just provide flexible enough mechanism (extending the automatic partitioning request structure), most of the logic, checks, assumptions about the OSs / partitions found should happen in the UI / client providing the feature. (Maybe adding some helper API later)

The backend logic assumes unique existing mount points (eg /home) for the requests (reuse/erase/remove). We could extend it with the device specification if/when we support multiple existing mount points and their selection in the UI (passing the device to the backend instead of mountpoint) but I am not sure we even want to support this case.

The kickstart API doesn't have to be public/published, now it is there just as ground for the discussion, tests, PartitioningRequest structure update and work on webui UI support.

Pykickstart support draft PR: pykickstart/pykickstart#499

Draft of kickstart tests: rhinstaller/kickstart-tests#1278

Webui draft PR: rhinstaller/anaconda-webui#424

TODO:

• we should handle bootloader partitions automagically - detect required partitions and check there is unambigous (efi or biosboot...) partition to delete (or preserve)
• check consistency of partitioning scheme
• reuse fstab mount options (/home is missing compression opts). I am afraid we don't have this data - but it must be the same for reusing /home via mount point assignment - need to check.
• update unit tests if needed, fix the tests
• ? check dual boot with Windows (currently only tested with multiple Fedora OSs)

[pep8speaks]

Hello @rvykydal! Thanks for updating this PR. We checked the lines you've touched for PEP 8 issues, and found:

• In the file tests/unit_tests/pyanaconda_tests/modules/storage/partitioning/test_module_part_automatic.py:

Line 422:100: E501 line too long (101 > 99 characters)
Line 693:100: E501 line too long (102 > 99 characters)
Line 694:100: E501 line too long (101 > 99 characters)

Comment last updated at 2024-10-08 12:18:05 UTC

[rvykydal]

Hello @vojtechtrefny, could you check if the solution makes sense?

[jkonecny12]

Thanks a lot and sorry for complicating this...

[rvykydal]

Thanks a lot and sorry for complicating this...

Thank you. My bad, the tests should have been already there in the PR

[rvykydal]

/kickstart-test --testtype smoke

[rvykydal]

I've added the unit tests, @jkonecny12 could you look at the PR again?

[jkonecny12]

This is great improvement! Thanks a lot!

[jkonecny12]

/packit build