Support upgrade checks

This adds the ``cloudkitty-status upgrade check`` command to CloudKitty.
For now, this tool checks the storage version and raises a warning in case
v1 is used.

Depends-On: https://review.openstack.org/#/c/615928/
Change-Id: I39dc98fb716392a22765f169e2da0d389b33b941
Story: 2003657
Task: 26124

cloudkitty/cli/status.py

@@ -0,0 +1,53 @@
+# Copyright 2018 Objectif Libre
+#
+#    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.
+#
+import sys
+
+from oslo_config import cfg
+from oslo_upgradecheck import upgradecheck
+
+from cloudkitty.i18n import _
+# Import needed to register storage options
+from cloudkitty import storage  # noqa
+
+
+CONF = cfg.CONF
+
+
+class CloudkittyUpgradeChecks(upgradecheck.UpgradeCommands):
+
+    def _storage_version(self):
+        if CONF.storage.version < 2:
+            return upgradecheck.Result(
+                upgradecheck.Code.WARNING,
+                'Storage version is inferior to 2. Support for v1 storage '
+                'will be dropped in a future release.',
+            )
+        return upgradecheck.Result(upgradecheck.Code.SUCCESS)
+
+    _upgrade_checks = (
+        (_('Storage version'), _storage_version),
+    )
+
+
+def main():
+    return upgradecheck.main(
+        conf=CONF,
+        project='cloudkitty',
+        upgrade_command=CloudkittyUpgradeChecks(),
+    )
+
+
+if __name__ == '__main__':
+    sys.exit(main())

cloudkitty/tests/cli/test_status.py

@@ -0,0 +1,39 @@
+# Copyright 2018 Objectif Libre
+#
+#    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 oslo_upgradecheck import upgradecheck
+
+from cloudkitty.cli import status
+from cloudkitty import tests
+
+
+class CloudKittyStatusCheckUpgradeTest(tests.TestCase):
+
+    def setUp(self):
+        super(CloudKittyStatusCheckUpgradeTest, self).setUp()
+        self._checks = status.CloudkittyUpgradeChecks()
+
+    def test_storage_version_with_v1(self):
+        self.conf.set_override('version', 1, 'storage')
+        self.assertEqual(
+            upgradecheck.Code.WARNING,
+            self._checks._storage_version().code,
+        )
+
+    def test_storage_version_with_v2(self):
+        self.conf.set_override('version', 2, 'storage')
+        self.assertEqual(
+            upgradecheck.Code.SUCCESS,
+            self._checks._storage_version().code,
+        )

doc/source/admin/cli/cloudkitty-status.rst

@@ -0,0 +1,85 @@
+=====================
+Cloudkitty Status CLI
+=====================
+
+This chapter documents :command:`cloudkitty-status`.
+
+For help on a specific :command:`cloudkitty-status` command, enter:
+
+.. code-block:: console
+
+   $ cloudkitty-status COMMAND --help
+
+cloudkitty-status
+=================
+
+:program:`cloudkitty-status` is a tool that provides routines for checking the
+status of a Cloudkitty deployment.
+
+The standard pattern for executing a :program:`cloudkitty-status` command is:
+
+.. code-block:: console
+
+    cloudkitty-status <category> <command> [<args>]
+
+Run without arguments to see a list of available command categories:
+
+.. code-block:: console
+
+    cloudkitty-status
+
+Categories are:
+
+* ``upgrade``
+
+Detailed descriptions are below.
+
+You can also run with a category argument such as ``upgrade`` to see a list of
+all commands in that category:
+
+.. code-block:: console
+
+    cloudkitty-status upgrade
+
+The following sections describe the available categories and arguments for
+:program:`cloudkitty-status`.
+
+cloudkitty-status upgrade
+=========================
+
+.. _cloudkitty-status-upgrade-check:
+
+cloudkitty-status upgrade check
+-------------------------------
+
+``cloudkitty-status upgrade check``
+  Performs a release-specific readiness check before restarting services with
+  new code. This command expects to have complete configuration and access
+  to the database.
+
+  **Return Codes**
+
+  .. list-table::
+     :widths: 20 80
+     :header-rows: 1
+
+     * - Return code
+       - Description
+     * - 0
+       - All upgrade readiness checks passed successfully and there is nothing
+         to do.
+     * - 1
+       - At least one check encountered an issue and requires further
+         investigation. This is considered a warning but the upgrade may be OK.
+     * - 2
+       - There was an upgrade status check failure that needs to be
+         investigated. This should be considered something that stops an
+         upgrade.
+     * - 255
+       - An unexpected error occurred.
+
+  **History of Checks**
+
+  **9.0.0 (Stein)**
+
+  * Checks that the storage interface version is 2 (which is default).

doc/source/admin/cli/index.rst

@@ -0,0 +1,10 @@
+Command-Line Interface Reference
+================================
+
+Information on the commands available through Cloudkitty's Command Line
+Interface (CLI) can be found in this section.
+
+.. toctree::
+   :maxdepth: 1
+
+   cloudkitty-status

doc/source/admin/index.rst

@@ -9,3 +9,4 @@ Administration Guide
    quick_deployment/index
    install/index
    configuration/index
+   cli/index

lower-constraints.txt

@@ -21,6 +21,7 @@ oslo.messaging==5.24.2 # Apache-2.0
 oslo.middleware==3.27.0 # Apache-2.0
 oslo.policy==0.5.0 # Apache-2.0
 oslo.utils==3.5.0 # Apache-2.0
+oslo.upgradecheck==0.1.1 # Apache-2.0
 SQLAlchemy==1.0.10 # MIT
 six==1.9.0 # MIT
 stevedore==1.5.0 # Apache-2.0

releasenotes/notes/status-upgrade-check-fdcf054643e071d8.yaml

@@ -0,0 +1,5 @@
+---
+features:
+  - |
+    A new ``cloudkitty-status upgrade check`` command has been added. It can be
+    used to validate a deployment before upgrading it from release N-1 to N.

requirements.txt

@@ -23,6 +23,7 @@ oslo.messaging>=5.24.2,!=9.0.0 # Apache-2.0
 oslo.middleware>=3.27.0 # Apache-2.0
 oslo.policy>=0.5.0 # Apache-2.0
 oslo.utils>=3.5.0 # Apache-2.0
+oslo.upgradecheck>=0.1.1 # Apache-2.0
 SQLAlchemy>=1.0.10,!=1.1.5,!=1.1.6,!=1.1.7,!=1.1.8 # MIT
 six>=1.9.0 # MIT
 stevedore>=1.5.0 # Apache-2.0

setup.cfg

@@ -28,6 +28,7 @@ console_scripts =
     cloudkitty-processor = cloudkitty.cli.processor:main
     cloudkitty-storage-init = cloudkitty.cli.storage:main
     cloudkitty-writer = cloudkitty.cli.writer:main
+    cloudkitty-status = cloudkitty.cli.status:main
 
 wsgi_scripts =
     cloudkitty-api = cloudkitty.api.app:build_wsgi_app