Firebase Auth - get provider ID

Question

I'm using the following code, to detect auth provider and log out properly

static func logOut() {
    let auth = FIRAuth.auth()!
    let provider = auth.currentUser?.providerID
    switch provider! {
        case "Facebook": FBSDKLoginManager().logOut()
        case "Google": GIDSignIn.sharedInstance().signOut()
        case "Twitter": Twitter.sharedInstance().sessionStore.logOutUserID(TWTRAPIClient.withCurrentUser().userID!)
        default:
            print("Unknown provider ID: \(provider!)")
            return
    }
    try! auth.signOut()
}

But the provider is always "Firebase". What am I doing wrong? 0_o Once that code throw "Facebook" when I was logged in twitter. Thanks in advance

UPD: Yeah, I actually can store auth provider in UserDefaults, but maybe it's Firebase bug. I'm using Firebase SDK 3.5.2

Answer 1

Since a user can sign into their Firebase Authentication account with multiple providers, the top-level provider ID will now (usually) be Firebase.

But the currentUser has a providerData property that provides information on the speciic providers. Looping over FIRAuth.auth()!.currentUser.providerData will give you the FIRUserInfo.providerID you're looking for.

See also this question about UIDs, which are in a similar situation: Firebase returns multiple IDs, Which is unique one?