Add placement-status upgrade check command

This adds the basic framework for the
placement-status upgrade check command which
is a community-wide goal for the Stein release.

A simple placeholder check is added which should
be replaced later when we have a real upgrade
check.

Change-Id: I9291386fe7fcbfc035c104ea9fdbe5eb875c4776
Story: 2003657
Task: 27518

doc/source/cli/index.rst

@@ -22,4 +22,5 @@ utilities:
    :maxdepth: 1
 
    placement-manage
+   placement-status
 

doc/source/cli/placement-status.rst

@@ -0,0 +1,91 @@
+..
+      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.
+
+================
+placement-status
+================
+
+Synopsis
+========
+
+::
+
+  placement-status <category> <command> [<args>]
+
+Description
+===========
+
+:program:`placement-status` is a tool that provides routines for checking the
+status of a Placement deployment.
+
+Options
+=======
+
+The standard pattern for executing a :program:`placement-status` command is::
+
+    placement-status <category> <command> [<args>]
+
+Run without arguments to see a list of available command categories::
+
+    placement-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::
+
+    placement-status upgrade
+
+These sections describe the available categories and arguments for
+:program:`placement-status`.
+
+Upgrade
+~~~~~~~
+
+.. _placement-status-checks:
+
+``placement-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 databases and services.
+
+  **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**
+
+  **1.0.0 (Stein)**
+
+  * Placeholder to be filled in with checks as they are added in Stein.

doc/source/index.rst

@@ -198,9 +198,10 @@ The following sub-sections provide notes on upgrading to a given target release.
 
 .. note::
 
-   As a reminder, the `nova-status upgrade check`_ tool can be used to help
-   determine the status of your deployment and how ready it is to perform an
-   upgrade.
+   As a reminder, the
+   :ref:`placement-status upgrade check <placement-status-checks>` tool can be
+   used to help determine the status of your deployment and how ready it is to
+   perform an upgrade.
 
 Ocata (15.0.0)
 ~~~~~~~~~~~~~~
@@ -312,7 +313,6 @@ Stein (19.0.0)
 * The default configuration value of ``[placement]/policy_file`` is changed
   from ``placement-policy.yaml`` to ``policy.yaml``
 
-.. _`nova-status upgrade check`: https://docs.openstack.org/nova/latest/cli/nova-status.html
 .. _`its own repository`: https://git.openstack.org/cgit/openstack/placement
 
 REST API

lower-constraints.txt

@@ -90,6 +90,7 @@ oslo.reports==1.18.0
 oslo.rootwrap==5.8.0
 oslo.serialization==2.18.0
 oslo.service==1.24.0
+oslo.upgradecheck==0.1.1
 oslo.utils==3.37.0
 oslo.versionedobjects==1.31.2
 oslo.vmware==2.17.0

placement/cmd/status.py

@@ -0,0 +1,55 @@
+#    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 placement.i18n import _
+
+
+class Checks(upgradecheck.UpgradeCommands):
+    """Checks for the ``placement-status upgrade check`` command.
+
+    Various upgrade checks should be added as separate methods in this class
+    and added to _upgrade_checks tuple.
+    """
+
+    def _check_placeholder(self):
+        # This is just a placeholder for upgrade checks, it should be
+        # removed when the actual checks are added
+        return upgradecheck.Result(upgradecheck.Code.SUCCESS)
+
+    # The format of the check functions is to return an
+    # oslo_upgradecheck.upgradecheck.Result
+    # object with the appropriate
+    # oslo_upgradecheck.upgradecheck.Code and details set.
+    # If the check hits warnings or failures then those should be stored
+    # in the returned Result's "details" attribute. The
+    # summary will be rolled up at the end of the check() method.
+    _upgrade_checks = (
+        # TODO(mriedem) In the future there should be some real checks added
+        # here, for example, making sure all resource providers have a
+        # root_provider_id set before the nested RPs compatibility code is
+        # removed. See bug 1799892 for details.
+        (_('Placeholder'), _check_placeholder),
+    )
+
+
+def main():
+    return upgradecheck.main(
+        cfg.CONF, project='placement', upgrade_command=Checks())
+
+
+if __name__ == '__main__':
+    sys.exit(main())

placement/tests/unit/cmd/test_status.py

@@ -0,0 +1,32 @@
+#    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.upgradecheck import Code
+import testtools
+
+from placement.cmd import status
+
+
+class TestUpgradeChecks(testtools.TestCase):
+    """Basic tests for the upgrade check framework.
+
+    The heavy lifting is done in the oslo.upgradecheck library and the
+    tests here do not attempt to test the internals of the library code.
+    """
+    def setUp(self):
+        super(TestUpgradeChecks, self).setUp()
+        self.cmd = status.Checks()
+
+    def test_check_placeholder(self):
+        check_result = self.cmd._check_placeholder()
+        self.assertEqual(
+            Code.SUCCESS, check_result.code)

releasenotes/notes/placement-status-upgrade-check-3aa412fd6cb1e4bc.yaml

@@ -0,0 +1,6 @@
+---
+upgrade:
+  - |
+    A ``placement-status upgrade check`` command is added which can be used
+    to check the readiness of a placement deployment before initiating an
+    upgrade.

requirements.txt

@@ -21,6 +21,7 @@ oslo.db>=4.40.0 # Apache-2.0
 oslo.policy>=1.35.0 # Apache-2.0
 oslo.i18n>=3.15.3 # Apache-2.0
 oslo.middleware>=3.31.0 # Apache-2.0
+oslo.upgradecheck>=0.1.1 # Apache-2.0
 oslo.versionedobjects>=1.31.2 # Apache-2.0
 os-traits>=0.4.0 # Apache-2.0
 microversion-parse>=0.2.1 # Apache-2.0

setup.cfg

@@ -41,8 +41,8 @@ oslo.policy.policies =
     placement = placement.policies:list_rules
 
 console_scripts =
-    # TODO(cdent): We will need some kind of placement-status, eventually
     placement-manage = placement.cmd.manage:main
+    placement-status = placement.cmd.status:main
 wsgi_scripts =
     placement-api = placement.wsgi:init_application