Remove vm_utils.VMHelper class

The XenAPI driver has the concept of helper classes. All methods
have been classmethods and the classes themselves are never
instantiated. As a result, they only add an extra namespace
lookup and provide no value.

Change-Id: If8a20501c9a9353359234441580552e41471722b

2 files changed, 37 insertions, 57 deletions

diff --git a/nova/tests/test_xenapi.py b/nova/tests/test_xenapi.py
index 9314c947f..072be5b19 100644
--- a/nova/tests/test_xenapi.py
+++ b/nova/tests/test_xenapi.py
@@ -703,7 +703,7 @@ class XenAPIVMTestCase(test.TestCase):
     def test_rescue(self):
         instance = self._create_instance()
         session = xenapi_conn.XenAPISession('test_url', 'root', 'test_pass')
-        vm_ref = vm_utils.VMHelper.lookup(session, instance.name)
+        vm_ref = vm_utils.lookup(session, instance.name)
 
         xenapi_fake.create_vbd(vm_ref, "swap", userdevice=1)
         xenapi_fake.create_vbd(vm_ref, "rootfs", userdevice=0)
@@ -715,7 +715,7 @@ class XenAPIVMTestCase(test.TestCase):
 
         vm = xenapi_fake.get_record('VM', vm_ref)
         rescue_name = "%s-rescue" % vm["name_label"]
-        rescue_ref = vm_utils.VMHelper.lookup(session, rescue_name)
+        rescue_ref = vm_utils.lookup(session, rescue_name)
         rescue_vm = xenapi_fake.get_record('VM', rescue_ref)
 
         vdi_uuids = []
@@ -1035,7 +1035,7 @@ class XenAPIDetermineDiskImageTestCase(test.TestCase):
         self.fake_instance.architecture = 'x86-64'
 
     def assert_disk_type(self, image_meta, expected_disk_type):
-        actual = vm_utils.VMHelper.determine_disk_image_type(image_meta)
+        actual = vm_utils.determine_disk_image_type(image_meta)
         self.assertEqual(expected_disk_type, actual)
 
     def test_machine(self):
@@ -1154,14 +1154,11 @@ class XenAPIAutoDiskConfigTestCase(test.TestCase):
 
         self.context = context.RequestContext(self.user_id, self.project_id)
 
-        @classmethod
-        def fake_create_vbd(cls, session, vm_ref, vdi_ref, userdevice,
+        def fake_create_vbd(session, vm_ref, vdi_ref, userdevice,
                             vbd_type='disk', read_only=False, bootable=True):
             pass
 
-        self.stubs.Set(vm_utils.VMHelper,
-                       "create_vbd",
-                       fake_create_vbd)
+        self.stubs.Set(vm_utils, 'create_vbd', fake_create_vbd)
 
     def assertIsPartitionCalled(self, called):
         marker = {"partition_called": False}
@@ -1251,14 +1248,11 @@ class XenAPIGenerateLocal(test.TestCase):
 
         self.context = context.RequestContext(self.user_id, self.project_id)
 
-        @classmethod
-        def fake_create_vbd(cls, session, vm_ref, vdi_ref, userdevice,
+        def fake_create_vbd(session, vm_ref, vdi_ref, userdevice,
                             vbd_type='disk', read_only=False, bootable=True):
             pass
 
-        self.stubs.Set(vm_utils.VMHelper,
-                       "create_vbd",
-                       fake_create_vbd)
+        self.stubs.Set(vm_utils, 'create_vbd', fake_create_vbd)
 
     def assertCalled(self, instance):
         ctx = context.RequestContext(self.user_id, self.project_id)
@@ -1281,11 +1275,9 @@ class XenAPIGenerateLocal(test.TestCase):
         instance = db.instance_update(self.context, instance['id'],
                                       {'instance_type_id': 5})
 
-        @classmethod
-        def fake_generate_swap(cls, *args, **kwargs):
+        def fake_generate_swap(*args, **kwargs):
             self.called = True
-        self.stubs.Set(vm_utils.VMHelper, 'generate_swap',
-                       fake_generate_swap)
+        self.stubs.Set(vm_utils, 'generate_swap', fake_generate_swap)
 
         self.assertCalled(instance)
 
@@ -1295,11 +1287,9 @@ class XenAPIGenerateLocal(test.TestCase):
         instance = db.instance_update(self.context, instance['id'],
                                       {'instance_type_id': 4})
 
-        @classmethod
-        def fake_generate_ephemeral(cls, *args):
+        def fake_generate_ephemeral(*args):
             self.called = True
-        self.stubs.Set(vm_utils.VMHelper, 'generate_ephemeral',
-                       fake_generate_ephemeral)
+        self.stubs.Set(vm_utils, 'generate_ephemeral', fake_generate_ephemeral)
 
         self.assertCalled(instance)
 
@@ -1307,7 +1297,7 @@ class XenAPIGenerateLocal(test.TestCase):
 class XenAPIBWUsageTestCase(test.TestCase):
     def setUp(self):
         super(XenAPIBWUsageTestCase, self).setUp()
-        self.stubs.Set(vm_utils.VMHelper, "compile_metrics",
+        self.stubs.Set(vm_utils, 'compile_metrics',
                        XenAPIBWUsageTestCase._fake_compile_metrics)
         self.flags(target_host='127.0.0.1',
                    xenapi_connection_url='test_url',
@@ -1651,7 +1641,7 @@ class XenAPISRSelectionTestCase(test.TestCase):
         stubs.stubout_session(self.stubs, stubs.FakeSessionForVMTests)
         session = xenapi_conn.XenAPISession('test_url', 'root', 'test_pass')
         self.assertRaises(exception.StorageRepositoryNotFound,
-                          vm_utils.VMHelper.safe_find_sr, session)
+                          vm_utils.safe_find_sr, session)
 
     def test_safe_find_sr_local_storage(self):
         """Ensure the default local-storage is found."""
@@ -1666,7 +1656,7 @@ class XenAPISRSelectionTestCase(test.TestCase):
                                             'Local storage',
                                             'i18n-key': 'local-storage'},
                               host_ref=host_ref)
-        expected = vm_utils.VMHelper.safe_find_sr(session)
+        expected = vm_utils.safe_find_sr(session)
         self.assertEqual(local_sr, expected)
 
     def test_safe_find_sr_by_other_criteria(self):
@@ -1679,7 +1669,7 @@ class XenAPISRSelectionTestCase(test.TestCase):
                                          type='lvm',
                                          other_config={'my_fake_sr': 'true'},
                                          host_ref=host_ref)
-        expected = vm_utils.VMHelper.safe_find_sr(session)
+        expected = vm_utils.safe_find_sr(session)
         self.assertEqual(local_sr, expected)
 
     def test_safe_find_sr_default(self):
@@ -1688,7 +1678,7 @@ class XenAPISRSelectionTestCase(test.TestCase):
         stubs.stubout_session(self.stubs, stubs.FakeSessionForVMTests)
         session = xenapi_conn.XenAPISession('test_url', 'root', 'test_pass')
         pool_ref = xenapi_fake.create_pool('')
-        expected = vm_utils.VMHelper.safe_find_sr(session)
+        expected = vm_utils.safe_find_sr(session)
         self.assertEqual(session.call_xenapi('pool.get_default_SR', pool_ref),
                          expected)
 
diff --git a/nova/tests/xenapi/stubs.py b/nova/tests/xenapi/stubs.py
index e36fd40e9..0a87110e6 100644
--- a/nova/tests/xenapi/stubs.py
+++ b/nova/tests/xenapi/stubs.py
@@ -37,13 +37,12 @@ def stubout_firewall_driver(stubs, conn):
 
 
 def stubout_instance_snapshot(stubs):
-    @classmethod
-    def fake_fetch_image(cls, context, session, instance, image, type):
+    def fake_fetch_image(context, session, instance, image, type):
         return {'root': dict(uuid=_make_fake_vdi(), file=None),
                 'kernel': dict(uuid=_make_fake_vdi(), file=None),
                 'ramdisk': dict(uuid=_make_fake_vdi(), file=None)}
 
-    stubs.Set(vm_utils.VMHelper, 'fetch_image', fake_fetch_image)
+    stubs.Set(vm_utils, 'fetch_image', fake_fetch_image)
 
     def fake_wait_for_vhd_coalesce(*args):
         #TODO(sirp): Should we actually fake out the data here
@@ -97,20 +96,18 @@ def stubout_is_vdi_pv(stubs):
 def stubout_determine_is_pv_objectstore(stubs):
     """Assumes VMs stu have PV kernels"""
 
-    @classmethod
-    def f(cls, *args):
+    def f(*args):
         return False
-    stubs.Set(vm_utils.VMHelper, '_determine_is_pv_objectstore', f)
+    stubs.Set(vm_utils, '_determine_is_pv_objectstore', f)
 
 
 def stubout_is_snapshot(stubs):
     """ Always returns true
         xenapi fake driver does not create vmrefs for snapshots """
 
-    @classmethod
-    def f(cls, *args):
+    def f(*args):
         return True
-    stubs.Set(vm_utils.VMHelper, 'is_snapshot', f)
+    stubs.Set(vm_utils, 'is_snapshot', f)
 
 
 def stubout_lookup_image(stubs):
@@ -123,8 +120,7 @@ def stubout_lookup_image(stubs):
 def stubout_fetch_image_glance_disk(stubs, raise_failure=False):
     """Simulates a failure in fetch image_glance_disk."""
 
-    @classmethod
-    def _fake_fetch_image_glance_disk(cls, context, session, instance, image,
+    def _fake_fetch_image_glance_disk(context, session, instance, image,
                                       image_type):
         if raise_failure:
             raise fake.Failure("Test Exception raised by "
@@ -139,18 +135,17 @@ def stubout_fetch_image_glance_disk(stubs, raise_failure=False):
         vdi_type = vm_utils.ImageType.to_string(image_type)
         return {vdi_type: dict(uuid=None, file=filename)}
 
-    stubs.Set(vm_utils.VMHelper, '_fetch_image_glance_disk',
+    stubs.Set(vm_utils, '_fetch_image_glance_disk',
               _fake_fetch_image_glance_disk)
 
 
 def stubout_create_vm(stubs):
     """Simulates a failure in create_vm."""
 
-    @classmethod
-    def f(cls, *args):
+    def f(*args):
         raise fake.Failure("Test Exception raised by " +
                            "fake create_vm")
-    stubs.Set(vm_utils.VMHelper, 'create_vm', f)
+    stubs.Set(vm_utils, 'create_vm', f)
 
 
 def _make_fake_vdi():
@@ -286,8 +281,7 @@ def stub_out_vm_methods(stubs):
     def fake_release_bootlock(self, vm):
         pass
 
-    @classmethod
-    def fake_generate_ephemeral(cls, *args):
+    def fake_generate_ephemeral(*args):
         pass
 
     def fake_wait_for_device(dev):
@@ -295,7 +289,7 @@ def stub_out_vm_methods(stubs):
 
     stubs.Set(vmops.VMOps, "_acquire_bootlock", fake_acquire_bootlock)
     stubs.Set(vmops.VMOps, "_release_bootlock", fake_release_bootlock)
-    stubs.Set(vm_utils.VMHelper, 'generate_ephemeral', fake_generate_ephemeral)
+    stubs.Set(vm_utils, 'generate_ephemeral', fake_generate_ephemeral)
     stubs.Set(vm_utils, '_wait_for_device', fake_wait_for_device)
 
 
@@ -344,32 +338,28 @@ def stub_out_migration_methods(stubs):
         vdi_rec['other_config']['nova_disk_type'] = 'root'
         return {'uuid': vdi_rec['uuid'], 'ref': vdi_ref}
 
-    @classmethod
-    def fake_get_vdi(cls, session, vm_ref):
+    def fake_get_vdi(session, vm_ref):
         vdi_ref = fake.create_vdi('derp', 'herp')
         vdi_rec = session.call_xenapi("VDI.get_record", vdi_ref)
         return vdi_ref, {'uuid': vdi_rec['uuid'], }
 
-    @classmethod
-    def fake_sr(cls, session, *args):
+    def fake_sr(session, *args):
         pass
 
-    @classmethod
-    def fake_get_sr_path(cls, *args):
+    def fake_get_sr_path(*args):
         return "fake"
 
     def fake_destroy(*args, **kwargs):
         pass
 
-    @classmethod
-    def fake_generate_ephemeral(cls, *args):
+    def fake_generate_ephemeral(*args):
         pass
 
     stubs.Set(vmops.VMOps, '_destroy', fake_destroy)
     stubs.Set(vmops.VMOps, '_move_disks', fake_move_disks)
-    stubs.Set(vm_utils.VMHelper, 'scan_default_sr', fake_sr)
-    stubs.Set(vm_utils.VMHelper, 'scan_sr', fake_sr)
+    stubs.Set(vm_utils, 'scan_default_sr', fake_sr)
+    stubs.Set(vm_utils, 'scan_sr', fake_sr)
     stubs.Set(vmops.VMOps, '_create_snapshot', fake_create_snapshot)
-    stubs.Set(vm_utils.VMHelper, 'get_vdi_for_vm_safely', fake_get_vdi)
-    stubs.Set(vm_utils.VMHelper, 'get_sr_path', fake_get_sr_path)
-    stubs.Set(vm_utils.VMHelper, 'generate_ephemeral', fake_generate_ephemeral)
+    stubs.Set(vm_utils, 'get_vdi_for_vm_safely', fake_get_vdi)
+    stubs.Set(vm_utils, 'get_sr_path', fake_get_sr_path)
+    stubs.Set(vm_utils, 'generate_ephemeral', fake_generate_ephemeral)