Cleanup instance_update so it only takes a UUID.

You know when you try to do something simple like tweak
instance_update and instance_update_and_get_original and
it turns out to have all these knock on effects? Yeah,
that.

I still think this is a good idea though. I'd like to live
in a future where we don't have instance ids at all at the
DB API level. We need to do this to get there.

Change-Id: Ia51d06beaec068a8544642a6a4bf489247ff61a0

nova/db/api.py

@@ -630,16 +630,16 @@ def instance_test_and_set(context, instance_id, attr, ok_states,
             context, instance_id, attr, ok_states, new_state)
 
 
-def instance_update(context, instance_id, values):
+def instance_update(context, instance_uuid, values):
     """Set the given properties on an instance and update it.
 
     Raises NotFound if instance does not exist.
 
     """
-    return IMPL.instance_update(context, instance_id, values)
+    return IMPL.instance_update(context, instance_uuid, values)
 
 
-def instance_update_and_get_original(context, instance_id, values):
+def instance_update_and_get_original(context, instance_uuid, values):
     """Set the given properties on an instance and update it. Return
     a shallow copy of the original instance reference, as well as the
     updated one.
@@ -652,7 +652,8 @@ def instance_update_and_get_original(context, instance_id, values):
 
     Raises NotFound if instance does not exist.
     """
-    return IMPL.instance_update_and_get_original(context, instance_id, values)
+    return IMPL.instance_update_and_get_original(context, instance_uuid,
+                                                 values)
 
 
 def instance_add_security_group(context, instance_id, security_group_id):

nova/db/sqlalchemy/api.py

@@ -1687,38 +1687,37 @@ def instance_test_and_set(context, instance_id, attr, ok_states,
 
 
 @require_context
-def instance_update(context, instance_id, values):
-
-    instance_ref = _instance_update(context, instance_id, values)[1]
+def instance_update(context, instance_uuid, values):
+    instance_ref = _instance_update(context, instance_uuid, values)[1]
     return instance_ref
 
 
 @require_context
-def instance_update_and_get_original(context, instance_id, values):
+def instance_update_and_get_original(context, instance_uuid, values):
     """Set the given properties on an instance and update it. Return
     a shallow copy of the original instance reference, as well as the
     updated one.
 
     :param context: = request context object
-    :param instance_id: = instance id or uuid
+    :param instance_uuid: = instance uuid
     :param values: = dict containing column values
 
     :returns: a tuple of the form (old_instance_ref, new_instance_ref)
 
     Raises NotFound if instance does not exist.
     """
-    return _instance_update(context, instance_id, values,
-            copy_old_instance=True)
+    return _instance_update(context, instance_uuid, values,
+                            copy_old_instance=True)
 
 
-def _instance_update(context, instance_id, values, copy_old_instance=False):
+def _instance_update(context, instance_uuid, values, copy_old_instance=False):
     session = get_session()
 
-    if utils.is_uuid_like(instance_id):
-        instance_ref = instance_get_by_uuid(context, instance_id,
+    if utils.is_uuid_like(instance_uuid):
+        instance_ref = instance_get_by_uuid(context, instance_uuid,
                                             session=session)
     else:
-        instance_ref = instance_get(context, instance_id, session=session)
+        raise exception.InvalidUUID(instance_uuid)
 
     if copy_old_instance:
         old_instance_ref = copy.copy(instance_ref)