lvm: lvm_pv on RHEL 8, role fixes, Molecule scenario and Python 3.6 unit tests - #399
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… module runs on RHEL 8 The vendored upstream module starts with `from __future__ import annotations`, which platform-python 3.6 on RHEL 8 rejects with "SyntaxError: future feature annotations is not defined" before the module runs. Use the preamble of the other in-house plugins instead and record the local patch in the vendored-plugins list.
Drive main() with a fake run_command that keeps the PV state in memory: create (with and without force), resize, remove, check mode, and the sysfs rescan path of SCSI, whole-disk and NVMe devices.
Modules run on the managed node, where RHEL 8 uses platform-python 3.6. The controller matrix (3.9+) cannot catch syntax 3.6 does not know, as lvm_pv showed. Enable the py36-target tox env and add a CI job that runs the module and module_utils tests in UBI 8: - the tests import the module_utils of ansible-core 2.16, the last series that supports Python 3.6 on the managed node, i.e. what the controller ships to a RHEL 8 host. ansible-core itself needs Python 3.10, so it is installed without dependencies on the runner and put on PYTHONPATH in the container. Dependabot keeps it on the latest 2.16 release. - pytest comes from a hash-pinned lockfile compiled under Python 3.6 (pytest 6.2.5, the last release for 3.6), which Dependabot does not watch, since it would pick releases without Python 3.6 support - conftest.py skips the plugin loader when the controller part of ansible-core cannot be imported - skipsdist for tox 3, since tox 4 does not run on Python 3.6 - ruff targets py37 for managed-node code and its tests, so the formatter no longer produces parenthesized context managers, and test_sqlite_query drops them
.github/unit-tests-py36/requirements.txt pins pytest 6.2.5 and, via importlib-metadata, zipp 3.6.0. Dependency Review fails on GHSA-6w46-j5rx-g56g (pytest) and GHSA-jfmj-5v4g-7637 (zipp). The fixed releases require Python 3.10 and 3.8, while the test runner has to run on the Python 3.6 of the modules under test. The pytest advisory needs other local users on the machine and the zipp one a crafted ZIP file opened with zipp.Path; the throwaway UBI 8 container has neither. Allowlist both, as monitoring-plugins does for its py39 lockfile. The remaining pins have no active advisory; the one against py 1.11.0 is withdrawn.
Hosts installed without LVM, e.g. from a cloud image, lack the LVM tools, and lvm_pv failed with "No such file or directory: pvs".
lvol refuses to shrink an LV without force=true, and the lvcreate/lvextend task never passed it, so `shrink: true` always aborted. Pass the LV's `force` subkey; shrinking needs both, like removing. In the present state lvol only uses force to allow shrinking.
…without size
subelements("pvs") failed on a VG entry with `state: absent` and no
`pvs`, and the label of the size check read `size`, which an LV entry
with `state: absent` does not need.
Owner and mode were set on the directory before mounting, where the mounted file system's root hides them. The second run then set them on that root and reported a change. ansible.posix.mount creates a missing mount point itself, so set owner and mode after mounting.
Debian cloud images have no mkfs.xfs, and XFS is the role's default, so creating a file system failed there. Install e2fsprogs and xfsprogs for the ext2/3/4 and xfs LVs in the inventory. The other fstypes of community.general.filesystem are left to the admin, since they are untested and not every supported distribution ships them.
On Debian and Ubuntu there is no restorecon, so mounting an LV failed. Check for "enabled" rather than "not disabled": without the SELinux Python bindings, the fact reads "Missing selinux Python library".
…sion in the lvm_pv comment For an existing LV, lvol takes N% of the space that is free in the VG right now as the new absolute size, instead of adding it to the LV. lvm_pv first shipped in community.general 11.0.0 (version_added and the first tag containing 367b28d76), not 12.2.0, as CONTRIBUTING.md already says. Also fix the typo in the second line of that comment.
prepare.yml builds a starting layout on three additional disks and converge changes it: growpart and PV grow on a partition, pesize, vgextend, removing a VG that holds an LV, lvextend with resizefs, 100%FREE and 100%VG, ext4 shrink, LV removal, mount options, owner, mode and SELinux labels, and the rejection of relative sizes. Runs on Debian 12/13, Rocky 8/9/10 and Ubuntu 22.04/24.04/26.04. The mount group is daemon, since Debian and Ubuntu call the nobody group nogroup, and the SELinux label check only runs where SELinux is enabled. Green on all eight systems, so lvm is marked as proven on all of them in COMPATIBILITY.md.
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On RHEL 8,
pvcreate / pvresizein thelvmrole failed withSyntaxError: future feature annotations is not defined. The vendoredlvm_pvmodule starts withfrom __future__ import annotations, which the platform-python 3.6 that Ansible picks on RHEL 8 does not know. A Molecule scenario written to reproduce it turned up five more bugs in the role.What changes
lvm_pvruns on RHEL 8. The module uses the preamble of the other in-house plugins, and the vendored-plugins list in CONTRIBUTING.md records the local patch.The module tests also run on Python 3.6. The controller matrix (3.9+) cannot catch syntax that only 3.6 rejects. A new job in
Linuxfabrik: Unit Testsruns the module and module_utils tests in UBI 8 on Python 3.6, against the module_utils of ansible-core 2.16 (the last series that supports Python 3.6 on the managed node, i.e. what the controller ships to a RHEL 8 host). Dependabot keeps it on the latest 2.16 release.tox -e py36-targetdoes the same locally. ruff treats managed-node code and its tests aspy37, so the formatter can no longer bring back syntax that 3.6 does not know.lvm_pvgets unit tests.Role fixes.
lvm2is installed; hosts deployed from a cloud image lackedpvs.mkfs.xfs.restorecononly runs where SELinux is enabled.shrink: truenever worked, becauselvolrefuses to shrink withoutforce: true. Shrinking now needs both, like removing.pvsor an LV withoutsize(state: absent) aborted the run.mount_owner,mount_groupandmount_modewere set on the directory underneath the mount and only took effect on the second run, which reported a change.README.
forceis required to remove or shrink an LV, andN%FREEon an existing LV sets it to N% of the space that is free right now.Testing
A new
lvmscenario builds a starting layout on three additional disks and changes it: growpart and PV grow on a partition,pesize, vgextend, removing a VG that still holds an LV, lvextend with resizefs,100%FREEand100%VG, ext4 shrink, LV removal, mount options, owner, mode, SELinux labels and the rejection of relative sizes. Green on Debian 12/13, Rocky 8/9/10 and Ubuntu 22.04/24.04/26.04, including idempotence. Before the fix, the same scenario reproduced theSyntaxErroron Rocky 8.The Python 3.6 unit-test job was run locally with podman in UBI 8 (124 tests); this PR is its first run on GitHub.
pre-commitis clean.Not tested: NVMe devices, check mode.