Do not inherit os_glance properties on snapshot

Glance uses properties like os_glance_importing_to_stores for internal
purposes. These should never be copied to a snapshot by nova. Further,
Glance would like to disallow setting these properties by namespace
entirely in the future.

This patch adds namespace support to our existing list of static
properties which are non-inheritable.

Change-Id: Ib5d9da46b1a0e467b968e3ec3e61125e06f99bfc

nova/compute/utils.py

@@ -68,6 +68,13 @@
     'img_signature_key_type',
     'img_signature_certificate_uuid'])
 
+# Properties starting with these namespaces are reserved for internal
+# use by other services. It does not make sense (and may cause a request
+# fail) if we include them in a snapshot.
+NON_INHERITABLE_IMAGE_NAMESPACES = frozenset([
+    'os_glance',
+])
+
 
 def exception_to_dict(fault, message=None):
     """Converts exceptions to a dict for use in notifications.
@@ -1268,6 +1275,9 @@ def initialize_instance_snapshot_metadata(context, instance, name,
     properties = image_meta['properties']
     keys_to_pop = set(CONF.non_inheritable_image_properties).union(
         NON_INHERITABLE_IMAGE_PROPERTIES)
+    for ns in NON_INHERITABLE_IMAGE_NAMESPACES:
+        keys_to_pop |= {key for key in properties
+                        if key.startswith(ns)}
     for key in keys_to_pop:
         properties.pop(key, None)
 

nova/tests/unit/compute/test_compute_utils.py

@@ -1536,6 +1536,7 @@ def test_initialize_instance_snapshot_metadata_removed_metadata(self):
             'deeeeeac-d75e-11e2-8271-1234567897d6',
             'image_some_key': 'some_value',
             'image_fred': 'barney',
+            'image_os_glance_importing_to_stores': '',
             'image_cache_in_nova': 'true'
         }
         image_meta = compute_utils.initialize_instance_snapshot_metadata(
@@ -1548,6 +1549,7 @@ def test_initialize_instance_snapshot_metadata_removed_metadata(self):
             self.assertNotIn(p, properties)
         for p in CONF.non_inheritable_image_properties:
             self.assertNotIn(p, properties)
+        self.assertNotIn('os_glance_importing_to_stores', properties)
 
 
 class PciRequestUpdateTestCase(test.NoDBTestCase):