Add zone instance in fabric in RSD 2.3

Change-Id: If272e36756e1d64ca7e380e6b2f7f8f78a95b1ba

rsd_lib/resources/v2_3/fabric/fabric.py

@@ -19,6 +19,7 @@ from sushy import exceptions
 from sushy.resources import base
 
 from rsd_lib.resources.v2_3.fabric import endpoint
+from rsd_lib.resources.v2_3.fabric import zone
 from rsd_lib import utils as rsd_lib_utils
 
 LOG = logging.getLogger(__name__)
@@ -51,6 +52,8 @@ class Fabric(base.ResourceBase):
 
     _endpoints = None  # ref to EndpointCollection instance
 
+    _zones = None  # ref to ZoneCollection instance
+
     def __init__(self, connector, identity, redfish_version=None):
         """A class representing a Fabric
 
@@ -84,9 +87,32 @@ class Fabric(base.ResourceBase):
 
         return self._endpoints
 
+    def _get_zone_collection_path(self):
+        """Helper function to find the ZoneCollection path"""
+        zone_col = self.json.get('Zones')
+        if not zone_col:
+            raise exceptions.MissingAttributeError(attribute='Zones',
+                                                   resource=self._path)
+        return rsd_lib_utils.get_resource_identity(zone_col)
+
+    @property
+    def zones(self):
+        """Property to provide reference to `ZoneCollection` instance
+
+        It is calculated once when it is queried for the first time. On
+        refresh, this property is reset.
+        """
+        if self._zones is None:
+            self._zones = zone.ZoneCollection(
+                self._conn, self._get_zone_collection_path(),
+                redfish_version=self.redfish_version)
+
+        return self._zones
+
     def refresh(self):
         super(Fabric, self).refresh()
         self._endpoints = None
+        self._zones = None
 
 
 class FabricCollection(base.ResourceCollectionBase):

rsd_lib/tests/unit/resources/v2_3/fabric/test_fabric.py

@@ -21,6 +21,7 @@ from sushy import exceptions
 
 from rsd_lib.resources.v2_3.fabric import endpoint
 from rsd_lib.resources.v2_3.fabric import fabric
+from rsd_lib.resources.v2_3.fabric import zone
 
 
 class FabricTestCase(testtools.TestCase):
@@ -107,6 +108,66 @@ class FabricTestCase(testtools.TestCase):
         self.assertIsInstance(self.fabric_inst.endpoints,
                               endpoint.EndpointCollection)
 
+    def test__get_zone_collection_path(self):
+        expected = '/redfish/v1/Fabrics/NVMeoE/Zones'
+        result = self.fabric_inst._get_zone_collection_path()
+        self.assertEqual(expected, result)
+
+    def test__get_zone_collection_path_missing_attr(self):
+        self.fabric_inst._json.pop('Zones')
+        self.assertRaisesRegex(
+            exceptions.MissingAttributeError, 'attribute Zones',
+            self.fabric_inst._get_zone_collection_path)
+
+    def test_zones(self):
+        # check for the underneath variable value
+        self.assertIsNone(self.fabric_inst._zones)
+        # | GIVEN |
+        self.conn.get.return_value.json.reset_mock()
+        with open('rsd_lib/tests/unit/json_samples/v2_3/'
+                  'zone_collection.json', 'r') as f:
+            self.conn.get.return_value.json.return_value = json.loads(f.read())
+        # | WHEN |
+        actual_zones = self.fabric_inst.zones
+        # | THEN |
+        self.assertIsInstance(actual_zones,
+                              zone.ZoneCollection)
+        self.conn.get.return_value.json.assert_called_once_with()
+
+        # reset mock
+        self.conn.get.return_value.json.reset_mock()
+        # | WHEN & THEN |
+        # tests for same object on invoking subsequently
+        self.assertIs(actual_zones,
+                      self.fabric_inst.zones)
+        self.conn.get.return_value.json.assert_not_called()
+
+    def test_zones_on_refresh(self):
+        # | GIVEN |
+        with open('rsd_lib/tests/unit/json_samples/v2_3/'
+                  'zone_collection.json', 'r') as f:
+            self.conn.get.return_value.json.return_value = json.loads(f.read())
+        # | WHEN & THEN |
+        self.assertIsInstance(self.fabric_inst.zones,
+                              zone.ZoneCollection)
+
+        # On refreshing the fabric instance...
+        with open('rsd_lib/tests/unit/json_samples/v2_3/'
+                  'fabric.json', 'r') as f:
+            self.conn.get.return_value.json.return_value = json.loads(f.read())
+        self.fabric_inst.refresh()
+
+        # | WHEN & THEN |
+        self.assertIsNone(self.fabric_inst._zones)
+
+        # | GIVEN |
+        with open('rsd_lib/tests/unit/json_samples/v2_3/'
+                  'zone_collection.json', 'r') as f:
+            self.conn.get.return_value.json.return_value = json.loads(f.read())
+        # | WHEN & THEN |
+        self.assertIsInstance(self.fabric_inst.zones,
+                              zone.ZoneCollection)
+
 
 class FabricCollectionTestCase(testtools.TestCase):