If you want to add additional data, you need to create a model class for your user and then store it in your Firebase database . In general, after sign up, you can create a node tree for user like picture. Then, you can get the info with user key that can get by calling FirebaseUser.
Read moreHow do I set Firebase authentication?
Get Started with Firebase Authentication on Websites
Read moreWhat is custom authentication in Firebase?
You can integrate Firebase Authentication with a custom authentication system by modifying your authentication server to produce custom signed tokens when a user successfully signs in . Your app receives this token and uses it to authenticate with Firebase.
Read moreCan Nodejs be used with Firebase?
Firebase provides the tools and infrastructure you need to develop, grow, and earn money from your app. This package supports web (browser), mobile-web, and server (Node. js) clients .
Read moreHow do I use custom authentication?
Signing in users
Read moreHow do I use Firebase authentication with REST API?
Connect your web app to Firebase, your REST API will handle the authentication by receiving the user credentials , then authenticating with the Firebase through the web APIs Password Authentication. Use the Firebase server SDK to generate custom authentication tokens, the token will be a JSON Web Token (JWT).
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