The type information for authenticator.sessionKey

[kyoya0819]

I am specifying a constant (user) for the sessionKey of Authenticator.
When I try to retrieve authenticator.sessionKey, it gets rounded to a string, and I can't get the detailed type information.

const authenticator = new Authenticator<UserData>(sessionStorage, {
    sessionKey: "user"
});

authenticator.sessionKey // -> string

I want to specify authenticator.sessionKey as the sessionKey when calling session.set, as shown below.

import { createCookieSessionStorage } from "@remix-run/node";

import { authenticator, UserData } from "~/scripts/server/user.server";

export const sessionStorage = createCookieSessionStorage<{
   user: UserData,
   // ... other data
}>({
   cookie: {
       // ...
   }
});

export const { getSession, commitSession, destroySession } = sessionStorage;

const session = await getSession(request.headers.get("Cookie"));
// ↓ TS2345: Argument of type string is not assignable to parameter of type "user"
session.set(authenticator.sessionKey, user);
// Using 'as' would prevent errors, but...
session.set(authenticator.sessionKey as "user", user);

I think it might be possible to achieve this by holding the configuration values in Generics, similar to User.

I would like to know if there are any needs or implementation difficulties for this idea.
If there are any points where the implementation approach is fundamentally wrong, please let me know.