Follow-up to 27c725c to move up `cache_clear`

Move up ``cache_clear()`` to ``ResourceBase._do_refresh()``
method. It saves on a lot of ``_do_refresh()`` overrides in
subclasses.

Also change to ``Sequence`` (from ``Iterable``) in the caching
implementation.

Follow-up of Change: I7404a15beb029cb282ac6b84bb8b8fdb97ebcd4c

Change-Id: Id6c6afcd9142bed0a7f59b9f8893fb86975a65bb

sushy/resources/base.py

@@ -316,12 +316,20 @@ class ResourceBase(object):
         resource specific refresh operations to be performed. This is a
         primitive method in the paradigm of Template design pattern.
 
+        As for the base implementation of this method the approach taken is:
+        On refresh, all sub-resources are marked as stale. That means
+        invalidate (or undefine) the exposed attributes for nested resources
+        for fresh evaluation in subsequent calls to those exposed attributes.
+        In other words greedy-refresh is not done for them, unless forced by
+        ``force`` argument.
+
         :param force: should force refresh the resource and its sub-resources,
             if set to True.
         :raises: ResourceNotFoundError
         :raises: ConnectionError
         :raises: HTTPError
         """
+        utils.cache_clear(self, force_refresh=force)
 
     def invalidate(self, force_refresh=False):
         """Mark the resource as stale, prompting refresh() before getting used.
@@ -400,13 +408,3 @@ class ResourceCollectionBase(ResourceBase):
         :returns: A list of ``_resource_type`` objects
         """
         return [self.get_member(id_) for id_ in self.members_identities]
-
-    def _do_refresh(self, force):
-        """Do refresh related activities.
-
-        Invalidate / Undefine the cache attributes here for fresh evaluation
-        in subsequent calls to `get_members()` method. Other similar activities
-        can also follow in future, if needed.
-        """
-        super(ResourceCollectionBase, self)._do_refresh(force=force)
-        utils.cache_clear(self, force)

sushy/resources/manager/manager.py

@@ -87,10 +87,6 @@ class Manager(base.ResourceBase):
         """
         super(Manager, self).__init__(connector, identity, redfish_version)
 
-    def _do_refresh(self, force):
-        super(Manager, self)._do_refresh(force=force)
-        utils.cache_clear(self, force)
-
     def get_supported_graphical_console_types(self):
         """Get the supported values for Graphical Console connection types.
 

sushy/resources/sessionservice/sessionservice.py

@@ -76,16 +76,6 @@ class SessionService(base.ResourceBase):
             self._conn, self._get_sessions_collection_path(),
             redfish_version=self.redfish_version)
 
-    def _do_refresh(self, force):
-        """Do custom resource specific refresh activities
-
-        On refresh, all sub-resources are marked as stale, i.e.
-        greedy-refresh not done for them unless forced by ``force``
-        argument.
-        """
-        super(SessionService, self)._do_refresh(force=force)
-        utils.cache_clear(self, force)
-
     def close_session(self, session_uri):
         """This function is for closing a session based on its id.
 

sushy/resources/system/bios.py

@@ -147,13 +147,3 @@ class Bios(base.ResourceBase):
                                           'OldPassword': old_password,
                                           'PasswordName': password_name})
         LOG.info('BIOS password %s is being changed', self.identity)
-
-    def _do_refresh(self, force=False):
-        """Do custom resource specific refresh activities
-
-        On refresh, all sub-resources are marked as stale, i.e.
-        greedy-refresh not done for them unless forced by ``force``
-        argument.
-        """
-        super(Bios, self)._do_refresh(force=force)
-        utils.cache_clear(self, force)

sushy/resources/system/ethernet_interface.py

@@ -73,13 +73,3 @@ class EthernetInterfaceCollection(base.ResourceCollectionBase):
                 if eth.status.health == res_cons.HEALTH_OK:
                     mac_dict[eth.mac_address] = eth.status.state
         return mac_dict
-
-    def _do_refresh(self, force=False):
-        """Do custom resource specific refresh activities
-
-        On refresh, all sub-resources are marked as stale, i.e.
-        greedy-refresh not done for them unless forced by ``force``
-        argument.
-        """
-        super(EthernetInterfaceCollection, self)._do_refresh(force)
-        utils.cache_clear(self, force)

sushy/resources/system/processor.py

@@ -142,13 +142,3 @@ class ProcessorCollection(base.ResourceCollectionBase):
         """
         super(ProcessorCollection, self).__init__(connector, path,
                                                   redfish_version)
-
-    def _do_refresh(self, force=False):
-        """Do custom resource specific refresh activities
-
-        On refresh, all sub-resources are marked as stale, i.e.
-        greedy-refresh not done for them unless forced by ``force``
-        argument.
-        """
-        super(ProcessorCollection, self)._do_refresh(force=force)
-        utils.cache_clear(self, force)

sushy/resources/system/simple_storage.py

@@ -83,7 +83,3 @@ class SimpleStorageCollection(base.ResourceCollectionBase):
         refreshed.
         """
         return utils.max_safe(self.disks_sizes_bytes)
-
-    def _do_refresh(self, force):
-        super(SimpleStorageCollection, self)._do_refresh(force=force)
-        utils.cache_clear(self, force)

sushy/resources/system/storage/storage.py

@@ -95,13 +95,6 @@ class Storage(base.ResourceBase):
             self._conn, utils.get_sub_resource_path_by(self, 'Volumes'),
             redfish_version=self.redfish_version)
 
-    def _do_refresh(self, force):
-        """Do resource specific refresh activities."""
-        # Note(deray): invalidate / undefine the attributes here for fresh
-        # evaluation in subsequent calls to it's exposed property.
-        super(Storage, self)._do_refresh(force=force)
-        utils.cache_clear(self, force)
-
 
 class StorageCollection(base.ResourceCollectionBase):
     """This class represents the collection of Storage resources"""
@@ -149,8 +142,3 @@ class StorageCollection(base.ResourceCollectionBase):
         refreshed.
         """
         return utils.max_safe(self.volumes_sizes_bytes)
-
-    def _do_refresh(self, force):
-        """Do resource specific refresh activities"""
-        super(StorageCollection, self)._do_refresh(force=force)
-        utils.cache_clear(self, force)

sushy/resources/system/storage/volume.py

@@ -62,7 +62,3 @@ class VolumeCollection(base.ResourceCollectionBase):
 
     # NOTE(etingof): for backward compatibility
     max_size_bytes = max_volume_size_bytes
-
-    def _do_refresh(self, force):
-        super(VolumeCollection, self)._do_refresh(force=force)
-        utils.cache_clear(self, force)

sushy/resources/system/system.py

@@ -332,16 +332,6 @@ class System(base.ResourceBase):
             self._conn, utils.get_sub_resource_path_by(self, "Storage"),
             redfish_version=self.redfish_version)
 
-    def _do_refresh(self, force):
-        """Do custom resource specific refresh activities
-
-        On refresh, all sub-resources are marked as stale, i.e.
-        greedy-refresh not done for them unless forced by ``force``
-        argument.
-        """
-        super(System, self)._do_refresh(force=force)
-        utils.cache_clear(self, force)
-
 
 class SystemCollection(base.ResourceCollectionBase):
 

sushy/tests/unit/test_utils.py

@@ -139,9 +139,6 @@ class BaseResource(resource_base.ResourceBase):
                 NestedResource(self._conn, "/nested_res2",
                                redfish_version=self.redfish_version)]
 
-    def _do_refresh(self, force):
-        utils.cache_clear(self, force)
-
 
 class CacheTestCase(base.TestCase):
 

sushy/utils.py

@@ -163,7 +163,7 @@ def cache_it(res_accessor_method):
         def _do_refresh(self, force):
           cache_clear(self, force)
 
-    If the returned value is a Sushy resource instance or an Iterable whose
+    If the returned value is a Sushy resource instance or a sequence whose
     element is of type Sushy resource it handles the case of calling the
     ``refresh()`` method of that resource. This is done to avoid unnecessary
     recreation of a new resource instance which got already created at the
@@ -215,7 +215,7 @@ def cache_it(res_accessor_method):
 
         if isinstance(cache_attr_val, base.ResourceBase):
             cache_attr_val.refresh(force=False)
-        elif isinstance(cache_attr_val, collections.Iterable):
+        elif isinstance(cache_attr_val, collections.Sequence):
             for elem in cache_attr_val:
                 if isinstance(elem, base.ResourceBase):
                     elem.refresh(force=False)
@@ -237,15 +237,15 @@ def cache_clear(res_selfie, force_refresh, only_these=None):
 
     :param res_selfie: the resource instance.
     :param force_refresh: force_refresh argument of ``invalidate()`` method.
-    :param only_these: expects an Iterable of specific method names
+    :param only_these: expects a sequence of specific method names
         for which the cached value/s need to be cleared only. When None, all
         the cached values are cleared.
     """
     cache_attr_names = setdefaultattr(
         res_selfie, CACHE_ATTR_NAMES_VAR_NAME, set())
     if only_these is not None:
-        if not isinstance(only_these, collections.Iterable):
+        if not isinstance(only_these, collections.Sequence):
-            raise TypeError("'only_these' must be Iterable.")
+            raise TypeError("'only_these' must be a sequence.")
 
         cache_attr_names = cache_attr_names.intersection(
             '_cache_' + attr for attr in only_these)
@@ -257,7 +257,7 @@ def cache_clear(res_selfie, force_refresh, only_these=None):
 
         if isinstance(cache_attr_val, base.ResourceBase):
             cache_attr_val.invalidate(force_refresh)
-        elif isinstance(cache_attr_val, collections.Iterable):
+        elif isinstance(cache_attr_val, collections.Sequence):
             for elem in cache_attr_val:
                 if isinstance(elem, base.ResourceBase):
                     elem.invalidate(force_refresh)