Add cyborg-status upgrade check command framework

This adds basic framework for cyborg-status upgrade
check commands. For now it has only "check_placeholder"
check implemented.
Real checks can be added to this tool in the future.

Change-Id: I4a180f9a1b25c75489ad3cfee30a7b55506e0bbd
Story: 2003657
Task: 26126

cyborg/cmd/status.py

@@ -0,0 +1,50 @@
+# Copyright (c) 2018 NEC, Corp.
+#
+#    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_config import cfg
+from oslo_upgradecheck import upgradecheck
+
+from cyborg.common.i18n import _
+
+
+class Checks(upgradecheck.UpgradeCommands):
+
+    """Various upgrade checks should be added as separate methods in this class
+    and added to _upgrade_checks tuple.
+    """
+
+    def _check_placeholder(self):
+        # TODO(whoami-rajat):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 = (
+        # In the future there should be some real checks added here
+        (_('Placeholder'), _check_placeholder),
+    )
+
+
+def main():
+    return upgradecheck.main(
+        cfg.CONF, project='cyborg', upgrade_command=Checks())
+
+if __name__ == '__main__':
+    sys.exit(main())

cyborg/tests/unit/cmd/test_status.py

@@ -0,0 +1,30 @@
+# Copyright (c) 2018 NEC, Corp.
+#
+#    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
+
+from cyborg.cmd import status
+from cyborg.tests import base
+
+
+class TestUpgradeChecks(base.TestCase):
+
+    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)

doc/source/cli/cyborg-status.rst

@@ -0,0 +1,78 @@
+=============
+cyborg-status
+=============
+
+Synopsis
+========
+
+::
+
+  cyborg-status <category> <command> [<args>]
+
+Description
+===========
+
+:program:`cyborg-status` is a tool that provides routines for checking the
+status of a Cyborg deployment.
+
+Options
+=======
+
+The standard pattern for executing a :program:`cyborg-status` command is::
+
+    cyborg-status <category> <command> [<args>]
+
+Run without arguments to see a list of available command categories::
+
+    cyborg-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::
+
+    cyborg-status upgrade
+
+These sections describe the available categories and arguments for
+:program:`cyborg-status`.
+
+Upgrade
+~~~~~~~
+
+.. _cyborg-status-checks:
+
+``cyborg-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**
+
+  **2.0.0 (Stein)**
+
+  * Placeholder to be filled in with checks as they are added in Stein.

doc/source/cli/index.rst

@@ -0,0 +1,8 @@
+================================
+Command-Line Interface Reference
+================================
+
+.. toctree::
+   :maxdepth: 1
+
+   cyborg-status

doc/source/index.rst

@@ -41,6 +41,19 @@ API
 
    admin/api
 
+CLI Reference
+-------------
+
+Information on the commands available through Cyborg's Command Line
+Interface (CLI) can be found in this section of documentation.
+
+
+.. toctree::
+   :maxdepth: 1
+
+   cli/index
+
+
 Developer Documentation
 -----------------------
 

releasenotes/notes/cyborg-status-upgrade-check-framework-567f8df30b971f13.yaml

@@ -0,0 +1,13 @@
+---
+prelude: >
+    Added new tool ``cyborg-status upgrade check``.
+features:
+  - |
+    New framework for ``cyborg-status upgrade check`` command is added.
+    This framework allows adding various checks which can be run before a
+    Cyborg upgrade to ensure if the upgrade can be performed safely.
+upgrade:
+  - |
+    Operator can now use new CLI tool ``cyborg-status upgrade check``
+    to check if Cyborg deployment can be safely upgraded from
+    N-1 to N release.

requirements.txt

@@ -15,6 +15,7 @@ oslo.messaging>=5.29.0 # Apache-2.0
 oslo.concurrency>=3.26.0 # Apache-2.0
 oslo.service>=1.0.0,!=1.28.1 # Apache-2.0
 oslo.db>=4.1.0 # Apache-2.0
+oslo.upgradecheck>=0.1.0 # Apache-2.0
 oslo.utils>=3.33.0 # Apache-2.0
 oslo.versionedobjects>=1.31.2 # Apache-2.0
 oslo.policy>=0.5.0 # Apache-2.0

setup.cfg

@@ -38,6 +38,7 @@ console_scripts =
     cyborg-conductor = cyborg.cmd.conductor:main
     cyborg-dbsync = cyborg.cmd.dbsync:main
     cyborg-agent = cyborg.cmd.agent:main
+    cyborg-status = cyborg.cmd.status:main
 wsgi_scripts =
     cyborg-wsgi-api = cyborg.api.wsgi_app:init_application