I believe Meteor.userId is initially null, but is then filled in with the id of the currently logged-in user. If there is no logged-in user, it stays null.
The question is, how do I know if there is a logged-in user, vs. when the client is waiting to find out if there is a logged in user? I’d like my app to know asap.
The reason I ask is that I want to put up a sign-in screen if the user is not logged in. If there is a logged-in user, I’d like to avoid them seeing the sign-in screen while the client is waiting to find out that they are logged in.
To put it another way: let’s say I had a “loading” message on screen, waiting to find out if there is a logged-in user. It so happens that in this case, there is no logged-in user. How would my app know that there is no logged-in user?
You need to use Meteor.loggingIn(). I use it like this on my react layouts
const user = Meteor.user();
const isLoggingIn = Meteor.loggingIn();
if (!isLoggingIn && !user) {
FlowRouter.go('login');
} else if (!isLoggingIn && user) {
// User is logged in
}
I don’t know if it’s documented anywhere, but Meteor.user() returns undefined before the login checks run on startup. After that, it returns null if no user is logged in, or a user object if a user is logged in.
It might be an issue on the future to rely on that, even more knowing that there might be a rewrite of those modules to TS. But not something to worry on the short term.
