From 4f2da1cc1d24cbc47025cc8613c0d3ec287a20f9 Mon Sep 17 00:00:00 2001 From: Daniel Watkins Date: Tue, 17 Nov 2020 16:37:29 -0500 Subject: introduce an upgrade framework and related testing (#659) This commit does the following: * introduces the `cloudinit.persistence` module, containing `CloudInitPickleMixin` which provides lightweight versioning of objects' pickled representations (and associated testing) * introduces a basic upgrade testing framework (in `cloudinit.tests.test_upgrade`) which unpickles pickles from previous versions of cloud-init (stored in `tests/data/old_pickles`) and tests invariants that the current cloud-init codebase expects * uses the versioning framework to address an upgrade issue where `Distro.networking` could get into an unexpected state, and uses the upgrade testing framework to confirm that the issue is addressed --- cloudinit/tests/test_upgrade.py | 45 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) create mode 100644 cloudinit/tests/test_upgrade.py (limited to 'cloudinit/tests/test_upgrade.py') diff --git a/cloudinit/tests/test_upgrade.py b/cloudinit/tests/test_upgrade.py new file mode 100644 index 00000000..f79a2536 --- /dev/null +++ b/cloudinit/tests/test_upgrade.py @@ -0,0 +1,45 @@ +# Copyright (C) 2020 Canonical Ltd. +# +# Author: Daniel Watkins +# +# This file is part of cloud-init. See LICENSE file for license information. + +"""Upgrade testing for cloud-init. + +This module tests cloud-init's behaviour across upgrades. Specifically, it +specifies a set of invariants that the current codebase expects to be true (as +tests in ``TestUpgrade``) and then checks that these hold true after unpickling +``obj.pkl``s from previous versions of cloud-init; those pickles are stored in +``tests/data/old_pickles/``. +""" + +import operator +import pathlib + +import pytest + +from cloudinit.stages import _pkl_load +from cloudinit.tests.helpers import resourceLocation + + +class TestUpgrade: + @pytest.fixture( + params=pathlib.Path(resourceLocation("old_pickles")).glob("*.pkl"), + scope="class", + ids=operator.attrgetter("name"), + ) + def previous_obj_pkl(self, request): + """Load each pickle to memory once, then run all tests against it. + + Test implementations _must not_ modify the ``previous_obj_pkl`` which + they are passed, as that will affect tests that run after them. + """ + return _pkl_load(str(request.param)) + + def test_networking_set_on_distro(self, previous_obj_pkl): + """We always expect to have ``.networking`` on ``Distro`` objects.""" + assert previous_obj_pkl.distro.networking is not None + + def test_blacklist_drivers_set_on_networking(self, previous_obj_pkl): + """We always expect Networking.blacklist_drivers to be initialised.""" + assert previous_obj_pkl.distro.networking.blacklist_drivers is None -- cgit v1.2.3