From 7530b165137df4470f304f72d5d831e8a0ca7ad1 Mon Sep 17 00:00:00 2001
From: Steven Hardy <shardy@redhat.com>
Date: Wed, 29 Jan 2014 13:58:13 +0000
Subject: [PATCH] API tolerate None environment string

If an API request has a None environment argument, we should not
reject the request, but treat it the same as an empty environment.

Change-Id: I812f308ef38833e89dfa2ce01263a297032f563a
Closes-Bug: #1273993
---
 heat/common/environment_format.py     | 5 +++--
 heat/tests/test_environment_format.py | 3 +++
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/heat/common/environment_format.py b/heat/common/environment_format.py
index 694aa0f8e6..4a69b8d9ec 100644
--- a/heat/common/environment_format.py
+++ b/heat/common/environment_format.py
@@ -24,9 +24,10 @@ SECTIONS = (PARAMETERS, RESOURCE_REGISTRY) = \
 def parse(env_str):
     '''
     Takes a string and returns a dict containing the parsed structure.
-    This includes determination of whether the string is using the
-    JSON or YAML format.
     '''
+    if env_str is None:
+        return {}
+
     try:
         env = yaml.load(env_str, Loader=yaml_loader)
     except yaml.YAMLError as yea:
diff --git a/heat/tests/test_environment_format.py b/heat/tests/test_environment_format.py
index ef8c1b55f5..ec5a1e5eb7 100644
--- a/heat/tests/test_environment_format.py
+++ b/heat/tests/test_environment_format.py
@@ -45,6 +45,9 @@ parameters: }
 '''
         self.assertRaises(ValueError, environment_format.parse, env)
 
+    def test_yaml_none(self):
+        self.assertEqual({}, environment_format.parse(None))
+
 
 class YamlParseExceptions(common.HeatTestCase):