From 32ceb7ae28ef85e93669273bd04689c96228c564 Mon Sep 17 00:00:00 2001
From: Boris Pavlovic <boris@pavlovic.me>
Date: Tue, 12 Mar 2013 11:10:54 +0400
Subject: Refactor work with session in db.block_device_mapping_* methods

Remove explicit use of session where it is not required.
Also this is small performance optimization, because if we put
session parameter to Models.save() method will create subtransaction.

blueprint db-session-cleanup

Change-Id: I6064f3df2daf0178009c4cf40da293f71ca6972a
---
 nova/db/sqlalchemy/api.py | 32 +++++++++++---------------------
 1 file changed, 11 insertions(+), 21 deletions(-)

diff --git a/nova/db/sqlalchemy/api.py b/nova/db/sqlalchemy/api.py
index 0bd9cfce7..e629281c5 100644
--- a/nova/db/sqlalchemy/api.py
+++ b/nova/db/sqlalchemy/api.py
@@ -2830,19 +2830,14 @@ def _block_device_mapping_get_query(context, session=None):
 def block_device_mapping_create(context, values):
     bdm_ref = models.BlockDeviceMapping()
     bdm_ref.update(values)
-
-    session = get_session()
-    with session.begin():
-        bdm_ref.save(session=session)
+    bdm_ref.save()
 
 
 @require_context
 def block_device_mapping_update(context, bdm_id, values):
-    session = get_session()
-    with session.begin():
-        _block_device_mapping_get_query(context, session=session).\
-                filter_by(id=bdm_id).\
-                update(values)
+    _block_device_mapping_get_query(context).\
+            filter_by(id=bdm_id).\
+            update(values)
 
 
 @require_context
@@ -2865,7 +2860,8 @@ def block_device_mapping_update_or_create(context, values):
         virtual_name = values['virtual_name']
         if (virtual_name is not None and
             block_device.is_swap_or_ephemeral(virtual_name)):
-            session.query(models.BlockDeviceMapping).\
+
+            _block_device_mapping_get_query(context, session=session).\
                 filter_by(instance_uuid=values['instance_uuid']).\
                 filter_by(virtual_name=virtual_name).\
                 filter(models.BlockDeviceMapping.device_name !=
@@ -2882,19 +2878,15 @@ def block_device_mapping_get_all_by_instance(context, instance_uuid):
 
 @require_context
 def block_device_mapping_destroy(context, bdm_id):
-    session = get_session()
-    with session.begin():
-        session.query(models.BlockDeviceMapping).\
-                filter_by(id=bdm_id).\
-                soft_delete()
+    _block_device_mapping_get_query(context).\
+            filter_by(id=bdm_id).\
+            soft_delete()
 
 
 @require_context
 def block_device_mapping_destroy_by_instance_and_volume(context, instance_uuid,
                                                         volume_id):
-    session = get_session()
-    with session.begin():
-        _block_device_mapping_get_query(context, session=session).\
+    _block_device_mapping_get_query(context).\
             filter_by(instance_uuid=instance_uuid).\
             filter_by(volume_id=volume_id).\
             soft_delete()
@@ -2903,9 +2895,7 @@ def block_device_mapping_destroy_by_instance_and_volume(context, instance_uuid,
 @require_context
 def block_device_mapping_destroy_by_instance_and_device(context, instance_uuid,
                                                         device_name):
-    session = get_session()
-    with session.begin():
-        _block_device_mapping_get_query(context, session=session).\
+    _block_device_mapping_get_query(context).\
             filter_by(instance_uuid=instance_uuid).\
             filter_by(device_name=device_name).\
             soft_delete()
-- 
cgit