Cinder Tempest plugin tests: Switch to stable interface

All the cinder tempest plugin tests are inherited from tempest/api/volume/base.py
which is not stable class and can be changed anytime by tempest.

One recent case where some changes in base class on tempest side could
have break the cinder tests-
 http://logs.openstack.org/07/522707/3/check/legacy-tempest-dsvm-full-devstack-plugin-ceph/a92cd60/logs/testr_results.html.gz

This commit switch cinder tests to use test.py which is stable interface
for plugin and create a base class with commonly used function & variable.

Change-Id: I0edda1fa23aed0b3d25691d5f4440a7234decc9a
Closes-Bug: #1734821
diff --git a/cinder/tests/tempest/api/volume/base.py b/cinder/tests/tempest/api/volume/base.py
new file mode 100644
index 0000000..b3765e0
--- /dev/null
+++ b/cinder/tests/tempest/api/volume/base.py
@@ -0,0 +1,170 @@
+# Copyright 2017 NEC Corporation.
+# 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.api.volume import api_microversion_fixture
+from tempest.common import compute
+from tempest.common import waiters
+from tempest import config
+from tempest.lib.common import api_version_utils
+from tempest.lib.common.utils import data_utils
+from tempest.lib.common.utils import test_utils
+from tempest.lib import exceptions
+from tempest import test
+
+CONF = config.CONF
+
+
+class BaseVolumeTest(api_version_utils.BaseMicroversionTest,
+                     test.BaseTestCase):
+    """Base test case class for all Cinder API tests."""
+
+    _api_version = 2
+    credentials = ['primary']
+
+    @classmethod
+    def skip_checks(cls):
+        super(BaseVolumeTest, cls).skip_checks()
+
+        if not CONF.service_available.cinder:
+            skip_msg = ("%s skipped as Cinder is not available" % cls.__name__)
+            raise cls.skipException(skip_msg)
+        if cls._api_version == 2:
+            if not CONF.volume_feature_enabled.api_v2:
+                msg = "Volume API v2 is disabled"
+                raise cls.skipException(msg)
+        elif cls._api_version == 3:
+            if not CONF.volume_feature_enabled.api_v3:
+                msg = "Volume API v3 is disabled"
+                raise cls.skipException(msg)
+        else:
+            msg = ("Invalid Cinder API version (%s)" % cls._api_version)
+            raise exceptions.InvalidConfiguration(msg)
+
+        api_version_utils.check_skip_with_microversion(
+            cls.min_microversion, cls.max_microversion,
+            CONF.volume.min_microversion, CONF.volume.max_microversion)
+
+    @classmethod
+    def setup_clients(cls):
+        super(BaseVolumeTest, cls).setup_clients()
+        if cls._api_version == 3:
+            cls.backups_client = cls.os_primary.backups_v3_client
+            cls.volumes_client = cls.os_primary.volumes_v3_client
+        else:
+            cls.backups_client = cls.os_primary.backups_v2_client
+            cls.volumes_client = cls.os_primary.volumes_v2_client
+
+        cls.snapshots_client = cls.os_primary.snapshots_v2_client
+
+    @classmethod
+    def setup_credentials(cls):
+        cls.set_network_resources()
+        super(BaseVolumeTest, cls).setup_credentials()
+
+    def setUp(self):
+        super(BaseVolumeTest, self).setUp()
+        self.useFixture(api_microversion_fixture.APIMicroversionFixture(
+            self.request_microversion))
+
+    @classmethod
+    def resource_setup(cls):
+        super(BaseVolumeTest, cls).resource_setup()
+        cls.request_microversion = (
+            api_version_utils.select_request_microversion(
+                cls.min_microversion,
+                CONF.volume.min_microversion))
+
+    @classmethod
+    def create_volume(cls, wait_until='available', **kwargs):
+        """Wrapper utility that returns a test volume.
+
+           :param wait_until: wait till volume status.
+        """
+        if 'size' not in kwargs:
+            kwargs['size'] = CONF.volume.volume_size
+
+        if 'imageRef' in kwargs:
+            image = cls.os_primary.image_client_v2.show_image(
+                kwargs['imageRef'])
+            min_disk = image['min_disk']
+            kwargs['size'] = max(kwargs['size'], min_disk)
+
+        if 'name' not in kwargs:
+            name = data_utils.rand_name(cls.__name__ + '-Volume')
+            kwargs['name'] = name
+
+        volume = cls.volumes_client.create_volume(**kwargs)['volume']
+        cls.addClassResourceCleanup(
+            cls.volumes_client.wait_for_resource_deletion, volume['id'])
+        cls.addClassResourceCleanup(test_utils.call_and_ignore_notfound_exc,
+                                    cls.volumes_client.delete_volume,
+                                    volume['id'])
+        waiters.wait_for_volume_resource_status(cls.volumes_client,
+                                                volume['id'], wait_until)
+        return volume
+
+    @classmethod
+    def create_snapshot(cls, volume_id=1, **kwargs):
+        """Wrapper utility that returns a test snapshot."""
+        if 'name' not in kwargs:
+            name = data_utils.rand_name(cls.__name__ + '-Snapshot')
+            kwargs['name'] = name
+
+        snapshot = cls.snapshots_client.create_snapshot(
+            volume_id=volume_id, **kwargs)['snapshot']
+        cls.addClassResourceCleanup(
+            cls.snapshots_client.wait_for_resource_deletion, snapshot['id'])
+        cls.addClassResourceCleanup(test_utils.call_and_ignore_notfound_exc,
+                                    cls.snapshots_client.delete_snapshot,
+                                    snapshot['id'])
+        waiters.wait_for_volume_resource_status(cls.snapshots_client,
+                                                snapshot['id'], 'available')
+        return snapshot
+
+    def create_backup(self, volume_id, backup_client=None, **kwargs):
+        """Wrapper utility that returns a test backup."""
+        if backup_client is None:
+            backup_client = self.backups_client
+        if 'name' not in kwargs:
+            name = data_utils.rand_name(self.__class__.__name__ + '-Backup')
+            kwargs['name'] = name
+
+        backup = backup_client.create_backup(
+            volume_id=volume_id, **kwargs)['backup']
+        self.addCleanup(backup_client.delete_backup, backup['id'])
+        waiters.wait_for_volume_resource_status(backup_client, backup['id'],
+                                                'available')
+        return backup
+
+    def create_server(self, wait_until='ACTIVE', **kwargs):
+        name = kwargs.pop(
+            'name',
+            data_utils.rand_name(self.__class__.__name__ + '-instance'))
+
+        tenant_network = self.get_tenant_network()
+        body, _ = compute.create_test_server(
+            self.os_primary,
+            tenant_network=tenant_network,
+            name=name,
+            wait_until=wait_until,
+            **kwargs)
+
+        self.addCleanup(test_utils.call_and_ignore_notfound_exc,
+                        waiters.wait_for_server_termination,
+                        self.os_primary.servers_client, body['id'])
+        self.addCleanup(test_utils.call_and_ignore_notfound_exc,
+                        self.os_primary.servers_client.delete_server,
+                        body['id'])
+        return body