Hello!

Redis has support for simple user-based ACLs for quite some time now:

https://redis.io/docs/management/security/acl/

The support for this is also built into PHPRedis:

https://github.com/phpredis/phpredis#auth

Currently, the caching plugin only allows using a password for login, which causes Redis to authenticate the "default" built-in user in the background:

https://git.in.moodle.com/moodle/moodle/-/blob/main/cache/stores/redis/lib.php#L274

Would it be possible to expose a "username" parameter as well?