Authentication trigger functions in Firebase - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is an Authentication trigger function in Firebase?

It is a special function that runs automatically when a user signs up or deletes their account in Firebase Authentication.

beginner

Name the two main types of Authentication trigger functions in Firebase.

The two main types are onCreate which runs when a user signs up, and onDelete which runs when a user account is deleted.

intermediate

How do Authentication trigger functions help in managing user data?

They let you automatically create or clean up user data in your database when users sign up or delete their accounts, keeping data consistent.

intermediate

Show a simple example of an onCreate Authentication trigger function in Firebase.

exports.createUserProfile = functions.auth.user().onCreate((user) => { return admin.firestore().collection('users').doc(user.uid).set({ email: user.email, createdAt: new Date() }); });

advanced

Why should Authentication trigger functions be used carefully?

Because they run automatically and can affect your database or other services, mistakes can cause data loss or errors. Always test and handle errors properly.

Which Firebase Authentication trigger runs when a user signs up?

A onCreate

B onDelete

C onUpdate

D onLogin

The onCreate trigger runs automatically when a new user account is created.

What does the onDelete Authentication trigger do?

A Runs when a user logs in

B Runs when a user updates their profile

C Runs when a user account is deleted

D Runs when a user resets password

The onDelete trigger runs automatically when a user account is deleted.

Why use Authentication trigger functions in Firebase?

A To automatically manage user data on sign up or deletion

B To speed up user login

C To change user passwords

D To send emails manually

They help keep user data in sync by running code automatically on user creation or deletion.

Which Firebase service is commonly used inside Authentication trigger functions to store user data?

A Firebase Hosting

B Cloud Firestore

C Firebase Analytics

D Firebase Storage

Cloud Firestore is often used to save or clean up user data triggered by Authentication events.

What should you always do when writing Authentication trigger functions?

A Ignore errors to keep functions fast

B Use them only for sending emails

C Run them manually only

D Test carefully and handle errors

Testing and error handling prevent data loss and unexpected problems.

Explain what Authentication trigger functions are and how they work in Firebase.

Think about what happens when a user signs up or deletes their account.

Describe a simple use case where you would use an onCreate Authentication trigger function.

Imagine you want to save new user info right after they join.