From 0a9c6c156a6eedf149528fd853f72a8ddd83e147 Mon Sep 17 00:00:00 2001 From: Stephen Finucane Date: Fri, 13 Dec 2019 16:18:33 +0000 Subject: [PATCH] Ensure option groups don't change during logging oslo.config allows us to configure groups and options dynamically. This can cause a race with our logging as we attempt to iterate through option groups that are changing under our feet. This wouldn't be a huge issue, since these are just logs are we can always log again, if needed, but we store groups in a dictionary and Python doesn't like us changing the size of a dict it's iterating through: RuntimeError: dictionary changed size during iteration Given that we're only reading through this option group and don't need to worry about a group _disappearing_, the solution is pretty simple: create a copy of our option group names ahead of time so we don't need to worry about new ones coming and messing things up. No tests are included since this is a race and the only way I see to reproduce this would involve lots of ugly threading. Change-Id: Id3b28465d645a24f0fcebff2dd68a9bd30e21594 Signed-off-by: Stephen Finucane Closes-Bug: #1856312 (cherry picked from commit e3e2ba55eeeb86a9bc0624bb2592e46583e839e7) (cherry picked from commit 22c286c63b15b6f0acf6f696b98226a9257bf745) --- oslo_config/cfg.py | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/oslo_config/cfg.py b/oslo_config/cfg.py index b151cff2..6a47cfd4 100644 --- a/oslo_config/cfg.py +++ b/oslo_config/cfg.py @@ -2566,7 +2566,7 @@ class ConfigOpts(collections.Mapping): logger.log(lvl, "%-30s = %s", opt_name, _sanitize(opt, getattr(self, opt_name))) - for group_name in self._groups: + for group_name in list(self._groups): group_attr = self.GroupAttr(self, self._get_group(group_name)) for opt_name in sorted(self._groups[group_name]._opts): opt = self._get_opt_info(opt_name, group_name)['opt']