openstack/placement
Code Issues Proposed changes

Let soft-deleted instance_system_metadata readable

Browse Source 
Currently, We can't delete instance system metadata after instance
is deleted because of following reason:
1) We might have 'changed-since' request which will access
the soft deleted system_metadata
2) We might has period audit function which also access the
soft deleted system_metadata

The root cause is the join function filtered the 'deleted'
data of system metadata and it lead to ValueError later.

Conceptually the system metadata is associated with instance,
it will be used in instance's lifecycle, the data will only
be updated so we won't have 2 copies or more system_metadata
for the same instance.
So allow to read it even if it's deleted is safe.

This patch load the system_metadata from db when instance is
in deleted state to avoid can't delete system_metadata issue.

Co-Authored-By: Alex Xu <hejie.xu@intel.com>

Change-Id: Ifd8d2c91879834d3759aafdb036dac209a246d1b
Partial-Bug: #1226049
This commit is contained in:
jichenjc
2014-07-19 16:41:50 +08:00
parent 44ae2e8646
commit b03a6836e6
2 changed files with 20 additions and 8 deletions
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16
nova/db/sqlalchemy/api.py
View File

@@ -2469,8 +2469,17 @@ def _instance_metadata_update_in_place(context, instance, metadata_type, model,
elif key not in metadata:
to_delete.append(keyvalue)
for condemned in to_delete:
condemned.soft_delete(session=session)
# NOTE: we have to hard_delete here otherwise we will get more than one
# system_metadata record when we read deleted for an instance;
# regular metadata doesn't have the same problem because we don't
# allow reading deleted regular metadata anywhere.
if metadata_type == 'system_metadata':
for condemned in to_delete:
session.delete(condemned)
instance[metadata_type].remove(condemned)
else:
for condemned in to_delete:
condemned.soft_delete(session=session)
for key, value in metadata.iteritems():
newitem = model()
@@ -4992,7 +5001,8 @@ def _instance_system_metadata_get_multi(context, instance_uuids,
if not instance_uuids:
return []
return model_query(context, models.InstanceSystemMetadata,
session=session, use_slave=use_slave).\
session=session, use_slave=use_slave,
read_deleted='yes').\
filter(
models.InstanceSystemMetadata.instance_uuid.in_(instance_uuids))

12
nova/utils.py
View File

@@ -828,11 +828,12 @@ def last_bytes(file_like_object, num):
return (file_like_object.read(), remaining)
def metadata_to_dict(metadata):
def metadata_to_dict(metadata, filter_deleted=False):
result = {}
for item in metadata:
if not item.get('deleted'):
result[item['key']] = item['value']
if not filter_deleted and item.get('deleted'):
continue
result[item['key']] = item['value']
return result
@@ -856,7 +857,8 @@ def instance_sys_meta(instance):
if isinstance(instance['system_metadata'], dict):
return instance['system_metadata']
else:
return metadata_to_dict(instance['system_metadata'])
return metadata_to_dict(instance['system_metadata'],
filter_deleted=True)
def get_wrapped_function(function):
@@ -1103,7 +1105,7 @@ def get_image_from_system_metadata(system_meta):
properties = {}
if not isinstance(system_meta, dict):
system_meta = metadata_to_dict(system_meta)
system_meta = metadata_to_dict(system_meta, filter_deleted=True)
for key, value in six.iteritems(system_meta):
if value is None: