Add test for Ceph backup snapshot cleanup option

This adds a new test for the Ceph backup snapshot cleanup
option. It tests a special situation in which a requested
incremental backup should become a full backup instead.

Depends-On: https://review.opendev.org/c/openstack/cinder/+/810457
Depends-On: https://review.opendev.org/c/openstack/devstack/+/860812
Signed-off-by: Jan Hartkopf <jhartkopf@inovex.de>
Change-Id: I8e539f58cc7c8b2a1d2c3036520cad9092a48638

.zuul.yaml

@@ -18,6 +18,7 @@
         - nova-ceph-multistore:
             voting: false
         - cinder-tempest-plugin-cbak-ceph
+        - cinder-tempest-plugin-ceph-cleanup
         - cinder-tempest-plugin-cbak-s3
         # As per the Tempest "Stable Branch Support Policy", Tempest will only
         # support the "Maintained" stable branches and not the "Extended Maintained"
@@ -218,6 +219,21 @@
       devstack_services:
         c-bak: true
 
+- job:
+    name: cinder-tempest-plugin-ceph-cleanup
+    parent: cinder-tempest-plugin-cbak-ceph
+    description: |
+      Integration test that runs the Ceph snapshot cleanup test.
+    vars:
+      devstack_local_conf:
+        test-config:
+          $TEMPEST_CONFIG:
+            volume-feature-enabled:
+              backup_keep_snapshots_option: True
+      devstack_localrc:
+        CINDER_BAK_CEPH_KEEP_SNAPSHOTS_COUNT: 1
+      tempest_test_regex: 'test_backup_snapshot_cleanup_incremental_forces_full_backup'
+
 - job:
     name: cinder-tempest-plugin-cbak-ceph-zed
     parent: cinder-tempest-plugin-cbak-ceph

cinder_tempest_plugin/config.py

@@ -22,6 +22,10 @@ cinder_option = [
     cfg.BoolOpt('volume_revert',
                 default=False,
                 help='Enable to run Cinder volume revert tests'),
+    cfg.BoolOpt('backup_keep_snapshots_option',
+                default=False,
+                help='Enable to run Cinder test for Ceph driver with '
+                     'backup_ceph_max_snapshots config option')
 ]
 
 # The barbican service is discovered by config_tempest [1], and will appear

cinder_tempest_plugin/scenario/test_ceph_backup_keep_snapshots_option.py

@@ -0,0 +1,81 @@
+# Copyright (c) 2022 inovex GmbH
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+from tempest import config
+from tempest.lib import decorators
+
+from cinder_tempest_plugin.api.volume import base
+
+CONF = config.CONF
+
+
+class VolumesBackupsTest(base.BaseVolumeTest):
+
+    @classmethod
+    def skip_checks(cls):
+        super(VolumesBackupsTest, cls).skip_checks()
+
+        if not CONF.volume_feature_enabled.backup_keep_snapshots_option:
+            raise cls.skipException("backup_ceph_max_snapshots "
+                                    "option not enabled")
+
+    @decorators.idempotent_id('10c43668-808e-48b6-bd37-92531f59183b')
+    def test_backup_snapshot_cleanup_incremental_forces_full_backup(self):
+        """Test incremental backup forces full backup after manual deletion."""
+
+        # Assume backup_ceph_max_snapshots is set to 1
+        # Create volume
+        volume = self.create_volume()
+
+        # Create base backup
+        self.create_backup(volume_id=volume['id'])
+
+        # Create 2 incremental backup snapshots
+        snapshots = []
+        for _ in range(2):
+            backup_incr = self.create_backup(
+                volume_id=volume['id'],
+                incremental=True)
+            snapshots.append(backup_incr)
+
+        # Snapshots are returned in reverse order of creation time
+        listed_snaps = self.backups_client.list_backups(detail=True)
+
+        self.assertEqual(listed_snaps['backups'][0]['id'], snapshots[1]['id'])
+        self.assertEqual(listed_snaps['backups'][1]['id'], snapshots[0]['id'])
+        self.assertTrue(listed_snaps['backups'][0]['is_incremental'])
+        self.assertFalse(listed_snaps['backups'][0]['has_dependent_backups'])
+
+        # Manually delete latest backup snapshot; this should force the next
+        # incremental backup to become a full backup.
+        # (At least backup_ceph_max_snapshots backup snapshots must be
+        # deleted to achieve this situation, which is 1 in our case, so 1
+        # deletion is sufficient.)
+        self.backups_client.delete_backup(snapshots[1]['id'])
+        self.backups_client.wait_for_resource_deletion(snapshots[1]['id'])
+
+        # Try to create incremental backup. As there are no base backups
+        # available anymore (one deleted by us, one by Ceph driver),
+        # this should automatically become a full backup.
+        backup_incr = self.create_backup(
+            volume_id=volume['id'],
+            incremental=True)
+
+        listed_snaps = self.backups_client.list_backups(detail=True)
+        self.assertEqual(listed_snaps['backups'][0]['id'], backup_incr['id'])
+
+        # Assert that, even though incremental backup was requested,
+        # a full backup was created
+        self.assertFalse(listed_snaps['backups'][0]['is_incremental'])