commands crash when don't have permissions to read config

[Pádraig Brady]

In summary running nova-all as a normal user that can't read /etc/nova/nova.conf
will result in a crash. This config file is only readable by 'nova' and 'root' on
Red Hat and Fedora systems for example.
Instead a "permission denied" message should be printed/logged,
rather than a crash and a confusing FileNotFound emitted.
The same is probably true for cinder-all etc.

Here is a a trace of what happens...

[bob@lxbsp2932 ~]$ nova-all
Traceback (most recent call last):
File "/usr/bin/nova-all", line 54, in <module>
flags.parse_args(sys.argv)
File "/usr/lib/python2.6/site-packages/nova/flags.py", line 43, in parse_args
default_config_files=default_config_files)
File "/usr/lib/python2.6/site-packages/nova/openstack/common/cfg.py", line 1026, in __call__
self._parse_config_files()
File "/usr/lib/python2.6/site-packages/nova/openstack/common/cfg.py", line 1496, in _parse_config_files
raise ConfigFilesNotFoundError(not_read_ok)
nova.openstack.common.cfg.ConfigFilesNotFoundError: Failed to read some config files: /etc/nova/nova.conf

Oct 26 16:49:27 lxbsp2932 abrt: detected unhandled Python exception in '/usr/bin/nova-all'
Oct 26 16:49:27 lxbsp2932 abrtd: New client connected
Oct 26 16:49:27 lxbsp2932 abrtd: Directory 'pyhook-2012-10-26-16:49:27-25525' creation detected
Oct 26 16:49:27 lxbsp2932 abrt-server[25530]: Saved Python crash dump of pid 25525 to /var/spool/abrt/pyhook-2012-10-26-16:49:27-25525
Oct 26 16:49:38 lxbsp2932 abrtd: Sending an email...
Oct 26 16:49:38 lxbsp2932 abrtd: Email was sent to: root@localhost
Oct 26 16:49:38 lxbsp2932 abrtd: New problem directory /var/spool/abrt/pyhook-2012-10-26-16:49:27-25525, processin

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/18674

[Mark McLoughlin (markmc)]

cfg should raise an exception and the caller should catch and print a nice error

Seems like cfg is raising an exception, it's just missing detailed error information (like "permission denied")

[Mark McLoughlin (markmc)]

Patch was auto-abandoned

[Doug Hellmann (doug-hellmann)]

This bug seems to be reporting the opposite behavior of https://bugs.launchpad.net/oslo.config/+bug/1265737 which claims the error is ignored or not reported and the default settings are used.

[moorryan (moorryan)]

Reproduce -
ubuntu@devstack1:/mnt/devstack$ sudo chmod 000 /etc/nova/nova.conf
ubuntu@devstack1:/mnt/devstack$ nova-all
Traceback (most recent call last):
  File "/usr/local/bin/nova-all", line 10, in <module>
    sys.exit(main())
  File "/opt/stack/nova/nova/cmd/all.py", line 49, in main
    config.parse_args(sys.argv)
  File "/opt/stack/nova/nova/config.py", line 40, in parse_args
    default_config_files=default_config_files)
  File "/usr/local/lib/python2.7/dist-packages/oslo/config/cfg.py", line 1683, in __call__
    raise ConfigFilesNotFoundError(self._namespace._files_not_found)
oslo.config.cfg.ConfigFilesNotFoundError: Failed to read some config files: /etc/nova/nova.conf

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/126888

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/126888
Committed: https://git.openstack.org/cgit/openstack/oslo.config/commit/?id=41770ad47f263bc88f380f009e8ab2d8c4de150d
Submitter: Jenkins
Branch: master

commit 41770ad47f263bc88f380f009e8ab2d8c4de150d
Author: Ryan Moore <email address hidden>
Date: Wed Oct 8 13:19:43 2014 +0100

    Report permission denied when parsing config

    Previously was returning ConfigFilesNotFoundError, when
    underlying error was 13 - Permission Denied

    Change-Id: I2c418f023c510205aa12a3acb9b09e6b1681f0d4
    Closes-Bug: #1071799

[Davanum Srinivas (DIMS) (dims-v)]

fixed in oslo