Custom authentication tokens in Firebase - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a custom authentication token in Firebase?

A custom authentication token is a secure token created by your server to sign in users with Firebase Authentication when you want to manage your own user identities.

beginner

Why would you use custom authentication tokens instead of Firebase's built-in sign-in methods?

You use custom tokens when you have your own user system or want to integrate Firebase Authentication with existing authentication methods outside Firebase.

intermediate

Which Firebase Admin SDK method is used to create a custom authentication token?

The method is createCustomToken(uid, additionalClaims) where uid is the user ID and additionalClaims are optional extra data.

beginner

What information must you include when creating a custom authentication token?

You must include a unique user ID (uid) and can optionally add extra claims like roles or permissions.

beginner

How does a client use a custom authentication token to sign in?

The client receives the token from your server and calls signInWithCustomToken(token) to authenticate with Firebase.

What is the main purpose of Firebase custom authentication tokens?

A To replace Firebase Realtime Database

B To create Firebase projects

C To store user data securely

D To sign in users with your own authentication system integrated with Firebase

Custom tokens let you sign in users using your own authentication system with Firebase Authentication.

Which Firebase SDK is used to create custom authentication tokens?

A Firebase Storage SDK

B Firebase Admin SDK

C Firebase Client SDK

D Firebase Hosting SDK

The Firebase Admin SDK runs on your server and creates custom tokens.

What is required to create a custom token?

A User's email only

B User's password

C A unique user ID (uid)

D Firebase API key

A unique user ID (uid) identifies the user in the token.

How does the client authenticate with Firebase using a custom token?

A By calling signInWithCustomToken(token)

B By calling signInWithEmailAndPassword

C By calling createUserWithEmailAndPassword

D By calling signOut

The client uses signInWithCustomToken(token) to authenticate with the custom token.

Can you add extra information like user roles in a custom token?

A Yes, as additional claims

B No, tokens only contain user ID

C Yes, but only in the client SDK

D No, Firebase does not support extra data

You can add extra claims like roles or permissions when creating the token.

Explain how custom authentication tokens work in Firebase and why you might use them.

Think about how your server and client communicate to authenticate users.

Describe the steps to create and use a custom authentication token in Firebase.

Focus on server token creation and client sign-in.