Fix renaming of instance fields using update_instance api method.

2 files changed, 19 insertions, 3 deletions

diff --git a/nova/api/ec2/apirequest.py b/nova/api/ec2/apirequest.py
index 2b1acba5a..d7ad08d2f 100644
--- a/nova/api/ec2/apirequest.py
+++ b/nova/api/ec2/apirequest.py
@@ -52,7 +52,23 @@ def _database_to_isoformat(datetimeobj):
 
 
 def _try_convert(value):
-    """Return a non-string if possible"""
+    """Return a non-string from a string or unicode, if possible.
+
+    ============= =====================================================
+    When value is returns
+    ============= =====================================================
+    zero-length   ''
+    'None'        None
+    'True'        True
+    'False'       False
+    '0', '-0'     0
+    0xN, -0xN     int from hex (postitive) (N is any number)
+    0bN, -0bN     int from binary (positive) (N is any number)
+    *             try conversion to int, float, complex, fallback value
+
+    """
+    if len(value) == 0:
+        return ''
     if value == 'None':
         return None
     if value == 'True':
diff --git a/nova/api/ec2/cloud.py b/nova/api/ec2/cloud.py
index c6309f03c..0d22a3f46 100644
--- a/nova/api/ec2/cloud.py
+++ b/nova/api/ec2/cloud.py
@@ -838,14 +838,14 @@ class CloudController(object):
         self.compute_api.unrescue(context, instance_id=instance_id)
         return True
 
-    def update_instance(self, context, ec2_id, **kwargs):
+    def update_instance(self, context, instance_id, **kwargs):
         updatable_fields = ['display_name', 'display_description']
         changes = {}
         for field in updatable_fields:
             if field in kwargs:
                 changes[field] = kwargs[field]
         if changes:
-            instance_id = ec2_id_to_id(ec2_id)
+            instance_id = ec2_id_to_id(instance_id)
             self.compute_api.update(context, instance_id=instance_id, **kwargs)
         return True