Firebase Auth using phone number and password

Question

I am developing Android app using Firebase. Because of that, I want to use Firebase Auth. I have following requirements:

• Register/Log in using Facebook
• Register/Log in using Email/Password
• Register/Log in using Phone Number/Password

The first two are OK, I followed basic tutorials. However, Phone Number / Password is the problem here. Firebase supports only Phone Number/SMS Token for this (its called Phone Auth), but there is no mention about my case. I do not want to hack Firebase and use its realtime database instead of Auth 'database'. Is there any better way to achieve this?

Thank you.

Answer 1

Use Fake Email:

Well, Firebase doesn't support sign in with mobile number and password but it supports email and password. So you can create a fake email with your mobile number.

Ie: 78******[email protected]

Also, you can create a complete Authentication system using it.

Registration:

• Input user mobile and password and proceed to the next page.

• Now use Firebase Phone Auth (OTP) to createUser. If process success, link fake email, password credentials in background.

  AuthCredential credential = EmailAuthProvider.getCredential(email, password); auth.getCurrentUser().linkWithCredential(credential);

Login:

• Input mobile and password to login. Convert the mobile in fake email and then signInWithEmailAndPassword().

Forget Password:

• Redirect the user to a new Page and user Phone Auth to verify the user. If successful, input a new password and change the password of the Email Auth.

Answer 2

If you have both email and phone of your user and you can use Admin SDK, then perhaps you could exchange users phone number to his email and login with email and password in the background.

Something like this (node.js)

admin.auth().getUserByPhoneNumber(phoneNumber)
    .then(user => {
        firebase.auth().signInWithEmailAndPassword(user.email, password);
    });