Sign in with Google on Android using Credential Manager and Supabase Auth

Summary

This tutorial walks you through the process of integrating Google Sign-In with the new Credential Manager in an Android app and connecting it to Supabase for secure authentication. It covers setting up dependencies, creating a Google Sign-In button, obtaining credentials, and handling exceptions. The video also demonstrates integrating Supabase authentication to allow users to insert data into a Supabase database securely. With step-by-step instructions, it explains how to set up the necessary authentication policies and successfully make authenticated API requests, ensuring a seamless user experience and secure data interactions.

Takeaways

• 😀 Google launched a Credential Manager for secure user sign-ins on Android apps in November.
• 😀 The Credential Manager replaces the previously recommended Google Sign-In method for Android applications.
• 😀 The tutorial shows how to integrate Google Sign-In with the new Credential Manager and connect it to Supabase authentication for secure API calls.
• 😀 The first step is to set up a new Android project and add necessary dependencies to the `build.gradle.kts` file for both Google Sign-In and Credential Manager.
• 😀 The process involves creating a Google Sign-In button with a custom composable function and configuring the GoogleIdOption for secure login settings.
• 😀 Developers need to generate a Google OAuth Client ID and configure it in both the Google Cloud Console and the app.
• 😀 To prevent replay attacks, a random nonce is generated and hashed using SHA-256 for the Google Sign-In process.
• 😀 The Google ID Token retrieved after successful sign-in is used to authenticate users in Supabase, ensuring secure access to the backend.
• 😀 After setting up Supabase, a test button is created to insert data into a Supabase database table. This verifies that authentication works correctly.
• 😀 The tutorial emphasizes the importance of setting Row-Level Security (RLS) policies in Supabase to control access to the data based on the authenticated user.
• 😀 The entire process includes handling Google Sign-In, setting up the correct OAuth credentials, and integrating with Supabase for secure data manipulation in the backend.

Q & A

What is the new credential manager introduced by Google?

The new credential manager is a way for developers to securely sign users into Android applications. Google announced it in November and is replacing the older method of using the 'ontop login' for Google Sign-In in Android apps.

How do you implement Google Sign-In using the credential manager?

To implement Google Sign-In using the credential manager, developers need to create a new composable function that includes a button labeled 'Sign in with Google.' The function will then handle the sign-in logic, including setting up the credential manager, creating an ID token, and using it for secure authentication.

What role does the Google Cloud Dashboard play in setting up Google Sign-In?

In the Google Cloud Dashboard, developers create OAuth client IDs for the application. One client ID is for Android, and another is for web applications. The web client ID is the one that should be used in the app for production. The process also includes setting up the app's package name and certificate fingerprint.

What is a nonce, and why is it important in the sign-in process?

A nonce is a random string used to prevent replay attacks during the OAuth process. It is passed during the sign-in process to ensure the integrity of the authentication. In the script, the nonce is generated using a random ID and hashed with the SHA-256 algorithm.

How is the credential manager's sign-in process integrated with Supabase authentication?

After obtaining the Google ID token from the credential manager, the app connects to Supabase by calling 'Supabase.auth.signInWith' and passing the ID token. This allows the user to authenticate and make secure API requests to Supabase.

What is the purpose of adding Supabase authentication to the app?

Supabase authentication is used to manage user identities and authorize secure access to backend resources. In this case, it ensures that users who sign in through Google Sign-In can securely interact with Supabase's database and API.

Why does the app initially fail to insert data into Supabase's 'posts' table?

The app fails to insert data initially because Supabase has Row Level Security (RLS) enabled by default, which restricts unauthorized access. Since the user has not authenticated yet, the insert operation is denied.

How do you enable authenticated users to insert data into Supabase?

To enable authenticated users to insert data into Supabase, developers need to create an RLS policy that allows users to insert data only if their authenticated user ID matches the user ID stored in the 'posts' table.

What is the significance of the 'user ID' column in Supabase's 'posts' table?

The 'user ID' column in the 'posts' table stores the authenticated user's unique Supabase ID. It is used to associate the data with a specific user and ensure that only the user who created the post can access or modify it.

What happens after the user successfully signs in using Google and Supabase authentication?

Once the user successfully signs in, they can proceed to make authenticated requests, such as inserting data into Supabase's database. The user ID is linked to the data, allowing them to interact with the system in a secure manner.