Github OAuth provider won't link with Google and Apple

[drekka]

• Swift
• iOS version: 16
• Firebase SDK version: 9.6.0
• FirebaseUI version: master branch (Using SPM to add to SwiftUI project)
• CocoaPods Version: N/A

Step 3: Describe the problem:

In my Firebase console authentication providers I have setup Google, Apple and Github as described in the Firebase UI doco. I also have also checked and enabled the automatic account linking option.

In my code (SwiftUI app) I have setup FirebaseAuthUI like this:

let authUI = FUIAuth.defaultAuthUI()!
authUI.delegate = self

authUI.providers = [
    FUIOAuth.appleAuthProvider(withAuthUI: authUI),
    FUIOAuth.githubAuthProvider(withAuthUI: authUI),
    FUIGoogleAuth(authUI: authUI),
]

So as to provide Apple, Google and Github sign on.

• I can sign in using either Apple or Google and the Firebase console shows an account with my ID and both providers linked.

• If I then try to sign on using Github I get the error

  Error Domain=FIRAuthErrorDomain Code=17012 "An account already exists with the same email address but different sign-in credentials. Sign in using a provider associated with this email address." UserInfo={FIRAuthErrorUserInfoNameKey=ERROR_ACCOUNT_EXISTS_WITH_DIFFERENT_CREDENTIAL, FIRAuthErrorUserInfoEmailKey=@gmail.com, FIRAuthErrorUserInfoUpdatedCredentialKey=<FIROAuthCredential: 0x6000009af520>, NSLocalizedDescription=An account already exists with the same email address but different sign-in credentials. Sign in using a provider associated with this email address.}

• If I remove the account via from the Firebase console, then sign in using Github it works and creates an account with the GitHub provider.

• If I then sign out and sign back in with a Google or Apple, it also logs in successfully. However when I check the Firebase console the GitHub provider has been removed from the account and replaced with the Google or Apple provider I signed in with.

It appears that the GitHib provider does not want to play nice with other providers.

Can you tell me if I'm doing anything wrong?

[drekka]

I've now managed to solve one problem. Specifically the problem where the GitHub provider won't sign on if there is an Apple or Google provider already registered. I did it with this code:

extension Security: FUIAuthDelegate {

    func authUI(_: FUIAuth, didSignInWith user: User?, error: Error?) {
        if let error {
            let nsError = error as NSError
            if nsError.code == AuthErrorCode.accountExistsWithDifferentCredential.rawValue {
                pendingAuth = nsError.userInfo[AuthErrorUserInfoUpdatedCredentialKey] as? AuthCredential
            }

            signOnViewModel.error = error
            return
        }

        if let user {
            if let pendingAuth {
                Auth.auth().currentUser?.link(with: pendingAuth) { result, error in
                    self.pendingAuth = nil
                }
            }
        }
    }

Essentially this is a hack of the code I found on the Firebase site for dealing with AuthErrorCode.accountExistsWithDifferentCredentials. I found that if there is already a registration with the same email but a different provide, then when I attempt to sign in with the GitHub provider it throws this error.

In my code I then stash the GitHub credentials and ask the user to sign in with a different provider. Once they do that, it then uses the stashed GitHub credentials to link the GitHub provider.

it works in that I end up with one registration with both GitHub and Apple/Google providers attached.

However it's not a great user experience.

Nor does it solve the issues of registering Appel/Google after GitHub removing Github as a provider.

I've tried poking around in Auth.auth() and FUIAuth.defaultAuthUI() but I've not been able to find anything that will tell me what has already been registered for a specific email. I've called Auth.auth().fetchSignInMethods(forEmail:...) but it always returns an empty array.

Any advice????