How to access firebase auth userMetadata - reactjs

Question

I'm trying to find a way to access the creationTime and lastSignInTime described in this documentation.
Are there any examples of using it within react hooks?
I can't make sense of the firebase documentation generally - it's just words on a page. I think it is designed for people who intuitively know how to fill in the blanks. I remain mystified as to how to do that in general.
I can access auth.user.email using a react hook as follows:
import React, { useState, useEffect, useContext, createContext } from "react";
import firebase from "../firebase";
import {auth} from "../firebase";
const authContext = createContext();
// Provider wraps app and makes auth object available by useAuth().
export function ProvideAuth({ children }) {
const auth = useProvideAuth();
return <authContext.Provider value={auth}>{children}</authContext.Provider>;
}
// Hook to get the auth
export const useAuth = () => {
return useContext(authContext);
};
// Provider hook that creates auth state
function useProvideAuth() {
const [user, setUser] = useState(null);
const signin = (email, password) => {
return firebase
.auth()
.signInWithEmailAndPassword(email, password)
.then(response => {
setUser(response.user);
return response.user;
});
};
const signup = (email, password) => {
return firebase
.auth()
.createUserWithEmailAndPassword(email, password)
.then(response => {
setUser(response.user);
return response.user;
});
};
const signout = () => {
return firebase
.auth()
.signOut()
.then(() => {
setUser(false);
});
};
const sendPasswordResetEmail = email => {
return firebase
.auth()
.sendPasswordResetEmail(email)
.then(() => {
return true;
});
};
const confirmPasswordReset = (code, password) => {
return firebase
.auth()
.confirmPasswordReset(code, password)
.then(() => {
return true;
});
};
useEffect(() => {
const unsubscribe = firebase.auth().onAuthStateChanged(user => {
if (user) {
setUser(user);
} else {
setUser(false);
}
});
return () => unsubscribe();
}, []);
return {
user,
signin,
signup,
signout,
sendPasswordResetEmail,
confirmPasswordReset
};
}
Now, I'm trying to figure out what I need to do to either access the string values described here or the timestamps described here.
I tried each of (all guesses):
{auth.user.UserMetadata().creationTime}
{auth.user.creationTime}
{auth.user.UserMetadata.creationTime}

Answer 1

This works.
{auth.user.metadata.creationTime}
I don't understand why. The references in the firebase documentation refer to metadata as UserMetadata. I don't know how to find the piece of information that tells people to make the leap between UserMetadata and metadata.
If anyone knows what the key to this is, I'd be forever grateful for the insight.