New method to calculate replicas for armada apps

Introduces _num_replicas_for_platform_app as a replacement
for _num_provisioned_controllers which is used to set the
number of replicas used by an platform armada application.

The new method will use the same unrderlying logic but will
never return a value less than 1. This will prevent having
the replicas set to 0 when there are no provisioned
controllers.

Tested with unit tests and by checking the replica count
after a host lock/unlock cycle.

Partial-Bug: 1922278
Signed-off-by: Isac Souza <IsacSacchi.Souza@windriver.com>
Change-Id: If322ff5d02996c9b853bc350244899c5e22431a2

sysinv/sysinv/sysinv/sysinv/helm/base.py

@@ -240,6 +240,20 @@ class BaseHelm(object):
                                   constants.AVAILABILITY_DEGRADED],
                     vim_progress_status=constants.VIM_SERVICES_ENABLED)
 
+    def _num_replicas_for_platform_app(self):
+        """
+        Returns the number of replicas that should be used by
+        platform managed applications. This method will return
+        the number of provisioned controllers, with a minimum of 1.
+
+        It takes care of the case where one controller is provisioned
+        and the other is installed but not provisioned. When the second
+        controller is provisioned, the unlock will check if the
+        overrides are different and reapply platform managed
+        applications appropriately
+        """
+        return max(1, self._num_provisioned_controllers())
+
     def _get_address_by_name(self, name, networktype):
         """
         Retrieve an address entry by name and scoped by network type

sysinv/sysinv/sysinv/sysinv/tests/helm/test_base.py

@@ -0,0 +1,32 @@
+# Copyright (c) 2021 Wind River Systems, Inc.
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+import mock
+
+from sysinv.helm.base import BaseHelm
+from sysinv.helm.helm import HelmOperator
+
+from sysinv.tests import base as test_base
+
+
+class TestHelmBase(test_base.TestCase):
+    def test_num_replicas_for_platform_app_0_controllers(self):
+        self.check_num_replicas_for_platform_app(num_provisioned_controllers=0, expected_replicas=1)
+
+    def test_num_replicas_for_platform_app_1_controllers(self):
+        self.check_num_replicas_for_platform_app(num_provisioned_controllers=1, expected_replicas=1)
+
+    def test_num_replicas_for_platform_app_2_controllers(self):
+        self.check_num_replicas_for_platform_app(num_provisioned_controllers=2, expected_replicas=2)
+
+    def check_num_replicas_for_platform_app(self, num_provisioned_controllers, expected_replicas):
+        mock_operator = mock.MagicMock(spec=HelmOperator)
+        mock_operator.dbapi = mock.MagicMock()
+        mock_operator.dbapi.count_hosts_matching_criteria.return_value = num_provisioned_controllers
+
+        base = BaseHelm(mock_operator)
+        actual_replicas = base._num_replicas_for_platform_app()
+
+        self.assertEqual(actual_replicas, expected_replicas)