From: Zane Bitter <zbitter@redhat.com>
Date: Mon, 26 Aug 2013 19:11:59 +0000 (+0200)
Subject: Add a DB API to swap two resources between stacks
X-Git-Tag: 2014.1~125^2
X-Git-Url: https://review.fuel-infra.org/gitweb?a=commitdiff_plain;h=fbd598b9ab5fdcb1db253a1e9115d65112989775;p=openstack-build%2Fheat-build.git

Add a DB API to swap two resources between stacks

When rolling back a stack update, we will need to swap the current and
previous (backup) resources so that the former moves to the backup stack
while the latter returns to the current stack. This API allows us to effect
the switch using a database transaction (thus avoiding having to create a
*third* stack).

Change-Id: I2b7247e384e3914778179260e198e5ae5c701525
---

diff --git a/heat/db/api.py b/heat/db/api.py
index c815a805..aea21db8 100644
--- a/heat/db/api.py
+++ b/heat/db/api.py
@@ -95,6 +95,10 @@ def resource_create(context, values):
     return IMPL.resource_create(context, values)
 
 
+def resource_exchange_stacks(context, resource_id1, resource_id2):
+    return IMPL.resource_exchange_stacks(context, resource_id1, resource_id2)
+
+
 def resource_get_all_by_stack(context, stack_id):
     return IMPL.resource_get_all_by_stack(context, stack_id)
 
diff --git a/heat/db/sqlalchemy/api.py b/heat/db/sqlalchemy/api.py
index b72d09c3..a3f61786 100644
--- a/heat/db/sqlalchemy/api.py
+++ b/heat/db/sqlalchemy/api.py
@@ -144,6 +144,19 @@ def resource_data_set(resource, key, value, redact=False):
     return current
 
 
+def resource_exchange_stacks(context, resource_id1, resource_id2):
+    query = model_query(context, models.Resource)
+    session = query.session
+    session.begin()
+
+    res1 = query.get(resource_id1)
+    res2 = query.get(resource_id2)
+
+    res1.stack, res2.stack = res2.stack, res1.stack
+
+    session.commit()
+
+
 def resource_data_delete(resource, key):
     result = resource_data_get_by_key(resource.context, resource.id, key)
     result.delete()