Firebase Auth (with Custom Token, for Linkedin) returns a user with no email and no data (only uid)

Question

I'm trying to login with Linkedin and Firebase. I generate on my server the custom token, I have my private key, I use RS256 and this is my payload:

"iss" :  service_account_email
"sub" :  service_account_email
"aud", "https://identitytoolkit.googleapis.com/google.identity.identitytoolkit.v1.IdentityToolkit"
"iat", Date().timeIntervalSince1970
"exp", Date().timeIntervalSince1970.advanced(by: 3600)
"uid", String.randomString(length:28)

I create the token, send it back to the app and from this I do:

Auth.auth().signIn(withCustomToken: token!, completion: { (user, error) in

I receive no error and a user back, so the token is valid. The problem is that the user has no values (no email, no displayName etc). the only thing is the uid which is the one that I set with: String.randomString(length:28)

How can I retrieve the user email and other info? In my linkedin account I have a displayname, email, picture etc. But here nothing.

Thanks

Answer 1

You have to set that manually. Firebase Auth has APIs to update profile (photo URL and display name) as well as email. You can send this LinkedIn data along with the custom token to your app, sign in with custom token and then update profile and email on that signed in custom token user.

By the way, set the LinkedIn ID as the UID for that user. Do not use a random string. Otherwise the next time you sign in with LinkedIn, the same user will map to another one.