Changing email for iOS Firebase user authenticated with email link

Question

So I have an iOS app that uses Firebase, signs users in anonymously initially and then allows them to later add an email address, which is linked to the Firebase user using a call to:

Auth.auth().currentUser?.linkAndRetrieveData(with: credential)

This all works fine but I'm now running into the issue of being unable to update that user's email. I assumed this would work by simply sending another email link to the new email, then calling linkAndRetrieveData with the new credentials.

This, however, gives me a FIRAuthErrorCodeProviderAlreadyLinked error, because the user already has an email address. I would've expected it to just overwrite the existing email. I then tried/considered to solutions:

1. Unlink the email provider, then relink with the new credentials. First, this seems impossible since the stated "providerId" for an email-link-authenticated user is "Firebase", and when I feed that into unlink it fails. Second, this is bug prone because you could successfully unlink the first email and then have the link of the new email fail.

2. Use the provided "updateEmail" method - this doesn't work because it assumes email/password authentication, and I'm using email link authentication. Even if this did work, it would mean having an unverified email.

So I'm wondering how to do this, or if it's actually possible that this isn't supported at all. I can't believe this wouldn't be supported since it seems like a very common issue and basically makes email link authentication a nonstarter.

Answer 1

updateEmail() is the method to change email for signed in user, no matter how the user was created or authenticated. You are right that the new email address would become unverified. The sendEmailVerification() method can then be triggered to send a verification email to the user, so they can verify the email address.

Answer 2

The providerID for an email link user should be "emailLink" (Android link, since I couldn't find the iOS version quickly, and the values come from the server anyway).

But note that a linked account will always have a top-level provider of "firebase", and then have the actual values of the linked accounts in the UserInfo elements of the provider array.