Remove unused root_metadata method of BlockDeviceMappingList

root_metadata method is no longer used, since
I067f66356a5ebd738add1591a0069d8049f35c24 changed the only place which
used it to do not do that.

The additional reasons to remove it are:
- it shouldn't be used with an instance bmds, because it's preferred to
get metadata from instance system metadata (see commit message of
I067f66356a5ebd738add1591a0069d8049f35c24);
- it doesn't look to work well with an arbitrary bdm list.

Related-Bug: #1439819
Change-Id: Id8c46cd5c20cbde2e9bf42a8af65f843895e19ed

nova/objects/block_device.py

@@ -299,26 +299,6 @@ class BlockDeviceMappingList(base.ObjectListBase, base.NovaObject):
         except StopIteration:
             return
 
-    def root_metadata(self, context, image_api, volume_api):
-        root_bdm = self.root_bdm()
-        if not root_bdm:
-            return {}
-
-        if root_bdm.is_volume:
-            try:
-                volume = volume_api.get(context, root_bdm.volume_id)
-                return volume.get('volume_image_metadata', {})
-            except Exception:
-                raise exception.InvalidBDMVolume(id=root_bdm.id)
-        elif root_bdm.is_image:
-            try:
-                image_meta = image_api.show(context, root_bdm.image_id)
-                return image_meta.get('properties', {})
-            except Exception:
-                raise exception.InvalidBDMImage(id=root_bdm.id)
-        else:
-            return {}
-
 
 def block_device_make_list(context, db_list, **extra_args):
     return base.obj_make_list(context,

nova/tests/unit/objects/test_block_device.py

@@ -347,47 +347,6 @@ class _TestBlockDeviceMappingListObject(object):
                     self.context, 'fake_instance_uuid'))
         self.assertEqual(0, len(bdm_list))
 
-    def test_root_volume_metadata(self):
-        fake_volume = {
-                'volume_image_metadata': {'vol_test_key': 'vol_test_value'}}
-
-        class FakeVolumeApi(object):
-            def get(*args, **kwargs):
-                return fake_volume
-
-        block_device_mapping = block_device_obj.block_device_make_list(None, [
-            fake_block_device.FakeDbBlockDeviceDict(
-                {'id': 1,
-                 'boot_index': 0,
-                 'source_type': 'volume',
-                 'destination_type': 'volume',
-                 'volume_id': 'fake_volume_id',
-                 'delete_on_termination': False})])
-
-        volume_meta = block_device_mapping.root_metadata(
-            self.context, None, FakeVolumeApi())
-        self.assertEqual(fake_volume['volume_image_metadata'], volume_meta)
-
-    def test_root_image_metadata(self):
-        fake_image = {'properties': {'img_test_key': 'img_test_value'}}
-
-        class FakeImageApi(object):
-            def show(*args, **kwargs):
-                return fake_image
-
-        block_device_mapping = block_device_obj.block_device_make_list(None, [
-            fake_block_device.FakeDbBlockDeviceDict(
-                {'id': 1,
-                 'boot_index': 0,
-                 'source_type': 'image',
-                 'destination_type': 'local',
-                 'image_id': "fake-image",
-                 'delete_on_termination': True})])
-
-        image_meta = block_device_mapping.root_metadata(
-            self.context, FakeImageApi(), None)
-        self.assertEqual(fake_image['properties'], image_meta)
-
 
 class TestBlockDeviceMappingListObject(test_objects._LocalTest,
                                        _TestBlockDeviceMappingListObject):