Mechanism to destroy all sessions?

I have a use case where the application can be set into a "maintenance mode".

When doing that, I'd like to destroy all current active sessions.

So far I only know that setting a session to `null` in a middleware, will destroy it. But it's mainly for the "sign out" use case.
Could koa-session provide an apocalypse method to destroy all?

Note I am using Redis, so I guess I could delete all session keys but I have more stuff than the sessions in there. I'd rather have a standard method independent of the store.

The issue names no files or tests. Start by reading the session middleware's handling of a session set to null and the Redis-backed store behavior. Done means defining a standard way to invalidate all active sessions without removing unrelated Redis data, while remaining independent of the session store.

Written by the indexing model from the issue text.