Allow missing `local_gb` property

Failure to detect ``local_gb`` fails the Redfish inspection.
But ideally it shouldn't fail, for instance the node can be a
disk-less node.

Allow Redfish inspect operation now to ignore missing ``local_gb``
property and set it to 0 in such cases.

Change-Id: I96fa83b81372333e626cca0e64fefcd0aeabe031
Story: 2004622
Task: 28542

doc/source/admin/drivers/redfish.rst

@@ -128,6 +128,12 @@ into the introspection ramdisk.
    Redfish specification. Not all Redfish-compliant BMCs might serve the
    required information, in which case bare metal node inspection will fail.
 
+.. note::
+
+   The ``local_gb`` property cannot always be discovered, for example, when a
+   node does not have local storage or the Redfish implementation does not
+   support the required schema. In this case the property will be set to 0.
+
 .. _Redfish: http://redfish.dmtf.org/
 .. _Sushy: https://git.openstack.org/cgit/openstack/sushy
 .. _TLS: https://en.wikipedia.org/wiki/Transport_Layer_Security

ironic/drivers/modules/redfish/inspect.py

@@ -115,6 +115,8 @@ class RedfishInspect(base.InspectInterface):
         simple_storage_size = 0
 
         try:
+            LOG.debug("Attempting to discover system simple storage size for "
+                      "node %(node)s", {'node': task.node.uuid})
             if (system.simple_storage and
                     system.simple_storage.disks_sizes_bytes):
                 simple_storage_size = [
@@ -132,6 +134,8 @@ class RedfishInspect(base.InspectInterface):
         storage_size = 0
 
         try:
+            LOG.debug("Attempting to discover system storage volume size for "
+                      "node %(node)s", {'node': task.node.uuid})
             if system.storage and system.storage.volumes_sizes_bytes:
                 storage_size = [
                     size for size in system.storage.volumes_sizes_bytes
@@ -145,6 +149,23 @@ class RedfishInspect(base.InspectInterface):
                       "for node %(node)s: %(err)s", {'node': task.node.uuid,
                                                      'err': ex})
 
+        try:
+            if not storage_size:
+                LOG.debug("Attempting to discover system storage drive size "
+                          "for node %(node)s", {'node': task.node.uuid})
+                if system.storage and system.storage.drives_sizes_bytes:
+                    storage_size = [
+                        size for size in system.storage.drives_sizes_bytes
+                        if size >= 4 * units.Gi
+                    ] or [0]
+
+                    storage_size = storage_size[0]
+
+        except sushy.exceptions.SushyError as ex:
+            LOG.debug("No storage drive information discovered "
+                      "for node %(node)s: %(err)s", {'node': task.node.uuid,
+                                                     'err': ex})
+
         # NOTE(etingof): pick the smallest disk larger than 4G among available
         if simple_storage_size and storage_size:
             local_gb = min(simple_storage_size, storage_size)
@@ -161,10 +182,11 @@ class RedfishInspect(base.InspectInterface):
 
         if local_gb:
             inspected_properties['local_gb'] = str(local_gb)
-
         else:
             LOG.warning("Could not provide a valid storage size configured "
-                        "for node %(node)s", {'node': task.node.uuid})
+                        "for node %(node)s. Assuming this is a disk-less node",
+                        {'node': task.node.uuid})
+            inspected_properties['local_gb'] = '0'
 
         valid_keys = self.ESSENTIAL_PROPERTIES
         missing_keys = valid_keys - set(inspected_properties)

ironic/tests/unit/drivers/modules/redfish/test_inspect.py

@@ -123,18 +123,6 @@ class RedfishInspectTestCase(db_base.DbTestCase):
             task.driver.inspect.inspect_hardware(task)
             self.assertEqual(expected_properties, task.node.properties)
 
-    @mock.patch.object(redfish_utils, 'get_system', autospec=True)
-    def test_inspect_hardware_fail_missing_local_gb(self, mock_get_system):
-        system_mock = self.init_system_mock(mock_get_system.return_value)
-        system_mock.simple_storage.disks_sizes_bytes = None
-        system_mock.storage.volumes_sizes_bytes = None
-
-        with task_manager.acquire(self.context, self.node.uuid,
-                                  shared=True) as task:
-            task.node.properties.pop('local_gb')
-            self.assertRaises(exception.HardwareInspectionFailure,
-                              task.driver.inspect.inspect_hardware, task)
-
     @mock.patch.object(redfish_utils, 'get_system', autospec=True)
     def test_inspect_hardware_ignore_missing_local_gb(self, mock_get_system):
         system_mock = self.init_system_mock(mock_get_system.return_value)
@@ -145,7 +133,7 @@ class RedfishInspectTestCase(db_base.DbTestCase):
                                   shared=True) as task:
             expected_properties = {
                 'cpu_arch': 'mips', 'cpus': '8',
-                'local_gb': '10', 'memory_mb': '2048'
+                'local_gb': '0', 'memory_mb': '2048'
             }
             task.driver.inspect.inspect_hardware(task)
             self.assertEqual(expected_properties, task.node.properties)