The rake task stats:cleanup is used by backend-cron to cleanup the stats keys for services that have been deleted.

The task accepts a list of Redis URLs, but when it converts it to Redis connections, it only uses the basic parameters - host and port. So, no username/password, and no TLS config (code).

This needs to be fixed.

Ideally, we wouldn't even need to pass the URL to the task, it actually can be confusing because some operations in this rake task already use Storage.instance which does support "extras". However, I guess we need to keep the explicit list for legacy purposes- because in SaaS we probably need to pass the list of actual servers that are behind the twemproxy.

So, I am thinking we might want to support both ways:

• if the list is passed, then use the list (even if it means that auth and TLS will not be supported)
• if empty list is passed, use Storage.instance - the caveat is that it must support SCAN command

Or maybe it's better to split this into two different tasks - one that requires the list, and the other one that does not.