From 7678f0c29c7678a2030eae71695ddb02c877c803 Mon Sep 17 00:00:00 2001
From: Steve Baker <sbaker@redhat.com>
Date: Wed, 23 Apr 2014 09:31:36 +1200
Subject: [PATCH] Prefetch data in resource_get_by_name_and_stack

This loads resource and resource data in a single query, which means
one less sql query per stack resource in a call to describe_stack_resource.

Change-Id: Ic2e1ab68cf651f290be75206fd5c0c841de4ef82
Related-Bug: #1306743
---
 heat/db/sqlalchemy/api.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/heat/db/sqlalchemy/api.py b/heat/db/sqlalchemy/api.py
index 86973b30ea..3ea2e67729 100644
--- a/heat/db/sqlalchemy/api.py
+++ b/heat/db/sqlalchemy/api.py
@@ -18,6 +18,7 @@ import sys
 
 from oslo.config import cfg
 import sqlalchemy
+from sqlalchemy import orm
 from sqlalchemy.orm.session import Session
 
 from heat.common import crypt
@@ -112,7 +113,8 @@ def resource_get(context, resource_id):
 def resource_get_by_name_and_stack(context, resource_name, stack_id):
     result = model_query(context, models.Resource).\
         filter_by(name=resource_name).\
-        filter_by(stack_id=stack_id).first()
+        filter_by(stack_id=stack_id).\
+        options(orm.joinedload("data")).first()
 
     return result