Set user identifier and UUID in Firebase

If you sign in with a custom token in Firebase, you'll notice that the identifier field of a user is left blank.

You can change the identifier field using updateEmail() function.


let { user, additionalUserInfo } = await firebase.auth().signInWithCustomToken(token);

await user.updateEmail('');

Now Jeff Bezos will have a User UID (UUID) generated by signInWithCustomToken() function and an email as identifier.

Hi, I'm Erik, an engineer from Barcelona. If you like the post or have any comments, say hi.