Firebase - onAuthStateChanged() 在登录和注册后触发

Question

I need to be able to figure out why did the listener fire - was it an initial sign up or sign in?

I tried using part of the user payload that comes with the callback. I tried comparing user.metadata.createdAt and user.metadata.lastLoginAt and this usually works - if I sign up, then sign out, and then sign in - it's all ok. But it is not ok when I sign up and then simply refresh the page.

Is there a way to see some metadata about when was the last time the auth status was changed or simple - to figure out if onAuthStateChanged fired because of a sign up or sign in.

Thanks!

Answer 1

The onAuthStateChanged() fires when the auth state changes, so that is indeed both for sign-ups and sign-ins.

If you want to distinguish between the two, you can:

• Either hook the explicit then that you get back from the signIn... / createUser method.
• Or you can compare the creationTime and lastSignInTime in theuser.metadata . If they're the same, the user was just created.