I implemented social login using firebase SDK and i tried login using my facebook account l got this error
An account already exists with the same email address but different sign-in credentials. Sign in using a provider associated with this email address
Note
I have only facebook and twitter login in my app and my facebook email not have twitter
when I reviewed user at firebase console l already have user with this email that was registered by facebook (the same provider)
How can the same provider generate different credentials?
You get this error when the user already signed in with the same email using a different provider. eg. user signs up with Twitter using user#example.com and then signs in with Facebook using user#example.com.
Since one account per email is enabled in the project settings, the only way to recover in this case is to sign in with the first provider (Twitter in the example above) and then linkWithCredential the Facebook credential to the existing Twitter account. By doing so, the user can sign in to the same account with either provider in the future.
Firebase Auth does this for security reasons. They want to verify that this is the same user signing in and do not want to automatically link without verifying the user's ownership of both account.
Related
I have project which has both an Android app and a Python Desktop-app (using pyrebase).
I'm using firebase for Authentication. For the Android, I've enabled both Google Authentication and Email Authentication.
For the Python, just email authentication (there doesn't seem to be a nice way to do Google Auth from python).
I have "Link accounts that use the same email" checked in Firebase Authentication Settings. Now suppose I:
Create user account with Email in desktop, and log in to it.
Sign in with Google Auth using the same email in android.
Try to log in again in desktop with same user-name and password.
Guess what happens? Log in does not work - the Google auth has "taken over" that account and is now the only way to authenticate (which means the account cannot be used from the desktop-app anymore)
Question: Is there any way to allow users to log into the SAME user account through EITHER google-auth OR email?
In my app, if a user registers using email and password, but later tries to log in or register using a Google account that shares that email, the account gets converted to a Google account and the user can no longer sign in with their email and password. I've configured the project with One account per email address setting on.
Is there any way of preventing this?
This is the expected behavior as Google accounts are verified: Firebase Overwrites Signin with Google Account
There are 2 ways around this:
1. Verify emails of password users. Google provider will be added to the account without unlinking the password if the user is verified.
2. You will need to switch to "multiple accounts per email", but this means 2 accounts will be created here, one email/password and another for Google.
I recommend the first approach. Firebase Auth does this for security reasons. Any person can claim an email. Unless the ownership is verified, the password must be unlinked to prevent the impersonator from gaining access to the account.
I have a current database with active users in Firebase that can login with user/pwd but now I'm implementing the facebook login and I realised the only way to link a facebook account with an existing user is only when the user is already logged with the user/pwd but not before the login.
I have two buttons in my app (login with fb and with email) but if I try to login with fb using the same email of an existing user, I will receive the following error auth/account-exists-with-different-credential and the documentation says that in order to fix this the user needs to login first then link.
Do you know if there is a way to link both accounts but without perform a login first, I mean, from the login view?
You need to sign in the user first before linking. This is important if you want to ensure it is the same user. Otherwise you can switch to multiple accounts per email in the Firebase console.
The way to solve this, when you get the error auth/account-exists-with-different-credential, the error will contain error.email and error.credential after you sign in with Facebook and the account already exists as a password account.
You then call firebase.auth().fetchProvidersForEmail(error.email) to which resolves with the list of provider IDs for that email. In this case, it will contain ['password']. You then ask the user to provide their password. You call signInWithEmailAndPassword(error.email, password) to sign-in the original user. You then call firebase.auth().currentUser.linkWithCredential(error.credential) to link the Facebook credential to the password account. Now both accounts are merged and the user can sign in with either.
I fixed it by going to the Firebase console. then head over to the authentication section and select the Settings Tab. Afterwards, go to User account linking and check Create multiple accounts for each identity provider
I have an Android app with use Firebase authentication using email and password. Recently added Google provider now my users can sign in wih his Google account, the problem is the following
There's an existing user example#gmail.com registered on my app, later the user sign in with his Google account Firebase automatically change the provider of the account from email to Google, the problem the user sign out and try to login with his email/password and got a message
The password is invalid or the user does not have a password
I understand why happens, but users (you know they are users) get frustrated because can't login with his email/password
There's some way to tell Firebase to keep the user password or when a user login with Google and this convertion happens in order to notify to user
Note My app only allow one account per email
I found there's a method fetchProvidersForEmail I asume I can build a flow over that method that check which provider have the user and allow the user chose if want to keep if old password by asking and linking account or just continue
If I register with Facebook (x#x.com) and later log in with Google (y#y.com), but I do not have the same email address on both providers, there are 2 users created. How can I handle this situation?
Linking is typically used in three cases:
Automatically requested by the backend for security reasons: when a user signs in to google for example with email x#x and then logs out and tries to sign in with a new facebook account x#x. In this case the backend will not complete the second sign in without verifying that the second user is the same as the first user (since both use the same email). So in this case, the user has to sign to the google account and then link the second facebook account to the initial one.
Manually triggered by the developer: One common case here is that the user signs in to google with email x#x and remains signed in. The developer wants access to the user's facebook friends. So the developer will ask the user to link their facebook account to the already logged in google user.
Upgrading an anonymous user: Developer could automatically sign in users initially as anonymous and then prompt them to upgrade to a registered user. In this case you can call link on the anonymous user.
So auth.currentUser.link can be made on all kinds of users as long as the account you are linking is new and not already linked.
You'll want to use the Account Linking APIs to authenticate multiple providers for the same account. Docs for Web, Android, and iOS are available.