Add API to get the entity inventory path

This new API provides the inventory path for a given entity reference.
Currently, the Nova transfer of images feature fails if the datacenter
is located in folders. This API has to be called prior to any HTTP
access to datastores.

Change-Id: I14066601816584689fb955927496d250ed825dc2

oslo/vmware/vim_util.py

@@ -423,3 +423,50 @@ def get_vc_version(session):
     :return: vCenter version
     """
     return session.vim.service_content.about.version
+
+
+def get_inventory_path(vim, entity_ref, max_objects=100):
+    """Get the inventory path of a managed entity.
+
+    :param vim: Vim object
+    :param entity_ref: managed entity reference
+    :param max_objects: maximum number of objects that should be returned in
+                        a single call
+    :return: inventory path of the entity_ref
+    """
+    client_factory = vim.client.factory
+    property_collector = vim.service_content.propertyCollector
+
+    prop_spec = build_property_spec(client_factory, 'ManagedEntity',
+                                    ['name', 'parent'])
+    select_set = build_selection_spec(client_factory, 'ParentTraversalSpec')
+    select_set = build_traversal_spec(
+        client_factory, 'ParentTraversalSpec', 'ManagedEntity', 'parent',
+        False, [select_set])
+    obj_spec = build_object_spec(client_factory, entity_ref, select_set)
+    prop_filter_spec = build_property_filter_spec(client_factory,
+                                                  [prop_spec], [obj_spec])
+    options = client_factory.create('ns0:RetrieveOptions')
+    options.maxObjects = max_objects
+    retrieve_result = vim.RetrievePropertiesEx(
+        property_collector,
+        specSet=[prop_filter_spec],
+        options=options)
+    entity_name = None
+    propSet = None
+    path = ""
+    while retrieve_result:
+        for obj in retrieve_result.objects:
+            if hasattr(obj, 'propSet'):
+                propSet = obj.propSet
+                if len(propSet) >= 1 and not entity_name:
+                    entity_name = propSet[0].val
+                elif len(propSet) >= 1:
+                    path = '%s/%s' % (propSet[0].val, path)
+        retrieve_result = continue_retrieval(vim, retrieve_result)
+    # NOTE(arnaud): slice to exclude the root folder from the result.
+    if propSet is not None and len(propSet) > 0:
+        path = path[len(propSet[0].val):]
+    if entity_name is None:
+        entity_name = ""
+    return '%s%s' % (path, entity_name)

tests/test_vim_util.py

@@ -17,6 +17,8 @@
 Unit tests for VMware API utility module.
 """
 
+import collections
+
 import mock
 
 from oslo.vmware import vim_util
@@ -319,3 +321,43 @@ class VimUtilTest(base.TestCase):
         session.vim.service_content.about.version = expected_version
         version = vim_util.get_vc_version(session)
         self.assertEqual(expected_version, version)
+
+    def test_get_inventory_path_folders(self):
+        ObjectContent = collections.namedtuple('ObjectContent', ['propSet'])
+        DynamicProperty = collections.namedtuple('Property', ['name', 'val'])
+
+        obj1 = ObjectContent(propSet=[
+            DynamicProperty(name='Datacenter', val='dc-1'),
+        ])
+        obj2 = ObjectContent(propSet=[
+            DynamicProperty(name='Datacenter', val='folder-2'),
+        ])
+        obj3 = ObjectContent(propSet=[
+            DynamicProperty(name='Datacenter', val='folder-1'),
+        ])
+        objects = ['foo', 'bar', obj1, obj2, obj3]
+        result = mock.sentinel.objects
+        result.objects = objects
+        session = mock.Mock()
+        session.vim.RetrievePropertiesEx = mock.Mock()
+        session.vim.RetrievePropertiesEx.return_value = result
+        entity = mock.Mock()
+        inv_path = vim_util.get_inventory_path(session.vim, entity, 100)
+        self.assertEqual('/folder-2/dc-1', inv_path)
+
+    def test_get_inventory_path_no_folder(self):
+        ObjectContent = collections.namedtuple('ObjectContent', ['propSet'])
+        DynamicProperty = collections.namedtuple('Property', ['name', 'val'])
+
+        obj1 = ObjectContent(propSet=[
+            DynamicProperty(name='Datacenter', val='dc-1'),
+        ])
+        objects = ['foo', 'bar', obj1]
+        result = mock.sentinel.objects
+        result.objects = objects
+        session = mock.Mock()
+        session.vim.RetrievePropertiesEx = mock.Mock()
+        session.vim.RetrievePropertiesEx.return_value = result
+        entity = mock.Mock()
+        inv_path = vim_util.get_inventory_path(session.vim, entity, 100)
+        self.assertEqual('dc-1', inv_path)