ec2-api crashes on describing volume backed snapshot

[Feodor Tersin]

If volume backed snapshot is available for an user euca-describe-images crashes due to 'unknown server error'.

Environment: DevStack

Steps to reproduce:

1 Create a volume backed snapshot
$ cinder create --image-id xxx 1
$ nova boot --flavor m1.nano --image xxx --block-device-mapping /dev/vda=yyy:::1 inst

2 List images to ensure the created snapshot is available.
$ glance image-list

3 Describe images by euca2ools
$ euca-describe-images
TypeError: Unknown error occurred.

nova-api.log
2014-05-26 23:16:18.070 ERROR nova.api.ec2 [req-105138c5-1b82-42ff-a5fd-4588a4262763 demo demo] Unexpected TypeError raised: int() argument must be a string or a number,
not 'NoneType'
2014-05-26 23:16:18.071 DEBUG nova.api.ec2.faults [req-105138c5-1b82-42ff-a5fd-4588a4262763 demo demo] EC2 error response: TypeError: Unknown error occurred. ec2_error_response /opt/stack/nova/nova/api/ec2/faults.py:29

[Feodor Tersin (ftersin)]

https://review.openstack.org/#/c/95580/

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/95580
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=68e008b21b463a261461a0f7bbfaa92f4e9a7e92
Submitter: Jenkins
Branch: master

commit 68e008b21b463a261461a0f7bbfaa92f4e9a7e92
Author: Feodor Tersin <email address hidden>
Date: Tue May 27 00:00:07 2014 +0400

    Skip none value attributes for ec2 image bdm output.

    Fix crash in _format_block_device_mapping when there are None values
    for formatting attributes in the mapping.

    Change-Id: I0ebdb844d75cdf1580cc88e1ff40fc21aff96f21
    Closes-Bug: #1323403