Add upgrade status check - instances with assigned tasks

This check detects Trove instances in state other than Active
(identified by assigned None tasks), as such instances have some
kind of activity running, which requires communication between
the instance and Trove control plane.

Change-Id: I64901fd27dc97de8ee5e3bc693ec966d4f1a3346
Signed-off-by: Dariusz Krol <d.krol@samsung.com>

doc/source/cli/trove-status.rst

@@ -75,4 +75,8 @@ Upgrade
 
   **11.0.0 (Stein)**
 
-  * Placeholder to be filled in with checks as they are added in Stein.
+  * Checks if any Trove instance with assigned task is running.
+    The assigned tasks may fail during the upgrade process due to transient
+    unavailability of Trove control plane.
+    Upgrade should be postponed until all instances are in the Active state.
+

trove/cmd/status.py

@@ -18,17 +18,38 @@ from oslo_config import cfg
 from oslo_upgradecheck import upgradecheck
 
 from trove.common.i18n import _
+from trove import db
+from trove.instance.models import DBInstance
+from trove.instance.tasks import InstanceTasks
 
 
 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):
-        # This is just a placeholder for upgrade checks, it should be
-        # removed when the actual checks are added
+    def _check_instances_with_running_tasks(self):
+        """Finds Trove instances with running tasks.
+
+        Such instances need to communicate with Trove control plane to report
+        status. This may rise issues if Trove services are unavailable, e.g.
+        Trove guest agent may be left in a failed state due to communication
+        issues.
+        """
+
+        db_api = db.get_db_api()
+        db_api.configure_db(cfg.CONF)
+
+        query = DBInstance.query()
+        query = query.filter(DBInstance.task_status != InstanceTasks.NONE)
+        query = query.filter_by(deleted=False)
+        instances_with_tasks = query.count()
+
+        if instances_with_tasks:
+            return upgradecheck.Result(
+                upgradecheck.Code.WARNING,
+                _("Instances with running tasks exist."))
+
         return upgradecheck.Result(upgradecheck.Code.SUCCESS)
 
     # The format of the check functions is to return an
@@ -39,14 +60,15 @@ class Checks(upgradecheck.UpgradeCommands):
     # 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),
+        (_("instances_with_running_tasks"),
+         _check_instances_with_running_tasks),
     )
 
 
 def main():
     return upgradecheck.main(
-        cfg.CONF, project='trove', upgrade_command=Checks())
+        cfg.CONF, project="trove", upgrade_command=Checks())
+
 
 if __name__ == '__main__':
     sys.exit(main())

trove/tests/unittests/cmd/test_status.py

@@ -12,19 +12,38 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from mock import Mock
+from mock import patch
 from oslo_upgradecheck.upgradecheck import Code
 
 from trove.cmd import status
 from trove.tests.unittests import trove_testtools
 
 
-class TestUpgradeChecks(trove_testtools.TestCase):
-
+@patch("trove.cmd.status.db.get_db_api")
+@patch("trove.cmd.status.DBInstance")
+class TestUpgradeChecksInstancesWithTasks(trove_testtools.TestCase):
     def setUp(self):
-        super(TestUpgradeChecks, self).setUp()
+        super(TestUpgradeChecksInstancesWithTasks, self).setUp()
         self.cmd = status.Checks()
+        self.fake_db_api = Mock()
 
-    def test__check_placeholder(self):
-        check_result = self.cmd._check_placeholder()
-        self.assertEqual(
-            Code.SUCCESS, check_result.code)
+    def test__check_no_instances_with_tasks(self, mock_instance,
+                                            fake_get_db_api):
+        fake_get_db_api.return_value = self.fake_db_api
+
+        mock_instance.query.return_value.filter.return_value.filter_by.\
+            return_value.count.return_value = 0
+
+        check_result = self.cmd._check_instances_with_running_tasks()
+        self.assertEqual(Code.SUCCESS, check_result.code)
+
+    def test__check_instances_with_tasks(self, mock_instance,
+                                         fake_get_db_api):
+        fake_get_db_api.return_value = self.fake_db_api
+
+        mock_instance.query.return_value.filter.return_value.filter_by.\
+            return_value.count.return_value = 1
+
+        check_result = self.cmd._check_instances_with_running_tasks()
+        self.assertEqual(Code.WARNING, check_result.code)