Multi Store feature failed in victoria version

[zhaoleilc]

Description
===========
An error occured when I configured multistores in openstack enviroment of
victoria verson deployed by devstack. The specific configuration complied
with the document as follows:
https://docs.openstack.org/glance/ussuri/admin/multistores.html

Steps to reproduce
==================
1. Deploy an openstack environment using devstack.
2. Configure lvm backend and rbd backend for cinder.
3. Configure glance-api.conf as follows:
[DEFAULT]
......
enabled_backends = rbd1:rbd, file1:file, cinderlvm:cinder, cinderceph:cinder

[glance_store]
default_backend = rbd1

[rbd1]
store_description = "rbd backend"
rbd_store_pool = images
rbd_store_user = glance
rbd_store_ceph_conf = /etc/ceph/ceph.conf
rbd_store_chunk_size = 8

[cinderlvm]
store_description = "cinderlvm backend"
cinder_volume_type = lvm-type

[cinderceph]
store_description = "cinderceph backend"
cinder_volume_type = ceph-type

[file1]
store_description = "file backend"
filesystem_store_datadir = /opt/stack/data/glance/images/

4. Restart glance-api service.
Expected result
===============
The 'glance stores-info' command returns four backends.

Actual result
=============
The glance-api service failed.

Environment
===========
Openstack enviroment of
victoria verson deployed by devstack

Logs & Configs
==============
Jan 16 16:16:20 devcon glance-api[3958867]: DEBUG glance_store.multi_backend [-] Attempting to import store cinder {{(pid=3958867) _load_multi_store /usr/local/lib/python3.6/dist-packages/glance_store/multi_backend.py:171}}
Jan 16 16:16:20 devcon glance-api[3958867]: DEBUG glance_store.common.fs_mount [-] Initialising _HostMountState {{(pid=3958867) __init__ /usr/local/lib/python3.6/dist-packages/glance_store/common/fs_mount.py:84}}
Jan 16 16:16:20 devcon glance-api[3958867]: DEBUG glance_store.capabilities [-] Store glance_store._drivers.cinder.Store doesn't support updating dynamic storage capabilities. Please overwrite 'update_capabilities' method of the store to implement updating logics if needed. {{(pid=3958867) update_capabilities /usr/local/lib/python3.6/dist-packages/glance_store/capabilities.py:95}}
Jan 16 16:16:20 devcon glance-api[3958867]: ERROR: 'NoneType' object has no attribute 'user'
Jan 16 16:16:20 devcon systemd[1]: <email address hidden>: Main process exited, code=exited, status=99/n/a
Jan 16 16:16:20 devcon systemd[1]: <email address hidden>: Failed with result 'exit-code'.

Workarounds
==============
root@devcon:/usr/local/lib/python3.6/dist-packages/glance_store# git diff
diff --git a/_drivers/cinder.py b/_drivers/cinder.py
index 2754017..551b088 100644
--- a/_drivers/cinder.py
+++ b/_drivers/cinder.py
@@ -415,7 +415,7 @@ class Store(glance_store.driver.Store):
         :raises: `exceptions.BackendException` if single store is defined and
                  it wasn't able to configure successfully
         """
- if self.backend_group:
+ if False:
             cinder_volume_type = self.store_conf.cinder_volume_type
             if cinder_volume_type:
                 # NOTE: `cinder_volume_type` is configured, check

As this configuration metod introduces backend_group, we can set it to False to workaround this issue.

[Dr. Jens Harbott (j-harbott)]

Does this still happen? Please try if it works on master for comparison.

[Launchpad Janitor (janitor)]

[Expired for devstack because there has been no activity for 60 days.]