Permit deleted instance types to be queried for active instances.

Fixes bug 994935.

This removes the deleted=0 restriction for joining instance_types
to instances. Active instances may be using old/deleted instance_types,
so we still need to be able to look up that information for show/detail
requests.

Change-Id: Ica72801f19c7e5b04966e53ed3ea4c330df44ed1

nova/tests/test_instance_types.py

@@ -152,7 +152,7 @@ class InstanceTypeTestCase(test.TestCase):
                           'name two', 256, 1, 120, 200, flavorid)
 
     def test_will_not_destroy_with_no_name(self):
-        """Ensure destroy sad path of no name raises error"""
+        """Ensure destroy said path of no name raises error"""
         self.assertRaises(exception.InstanceTypeNotFoundByName,
                           instance_types.destroy, None)
 
@@ -201,6 +201,24 @@ class InstanceTypeTestCase(test.TestCase):
         fetched = instance_types.get_instance_type_by_flavor_id(flavorid)
         self.assertEqual(default_instance_type, fetched)
 
+    def test_will_list_deleted_type_for_active_instance(self):
+        """Ensure deleted instance types with active instances can be read"""
+        ctxt = context.get_admin_context()
+        inst_type = instance_types.create("test", 256, 1, 120, 100, "test1")
+
+        instance_params = {"instance_type_id": inst_type["id"]}
+        instance = db.instance_create(ctxt, instance_params)
+
+        # NOTE(jk0): Delete the instance type and reload the instance from the
+        # DB. The instance_type object will still be available to the active
+        # instance, otherwise being None.
+        instance_types.destroy(inst_type["name"])
+        instance = db.instance_get_by_uuid(ctxt, instance["uuid"])
+
+        self.assertRaises(exception.InstanceTypeNotFound,
+                instance_types.get_instance_type, inst_type["name"])
+        self.assertTrue(instance["instance_type"])
+
 
 class InstanceTypeFilteringTest(test.TestCase):
     """Test cases for the filter option available for instance_type_get_all"""