AWS Amplify Google Login with Gen 2

I'll show you how to implement Google login with AWS Amplify Gen 2 in a Next.js application. AWS Amplify Gen 2 provides a more streamlined developer experience with improved TypeScript support and a more intuitive API.

Setting Up AWS Amplify Gen 2 with Google Authentication

To implement Google login with AWS Amplify Gen 2, follow these steps:

1. Set Up Your Google OAuth Credentials

1. Go to the Google Cloud Console
2. Create a new project or select an existing one
3. Navigate to "APIs & Services" > "Credentials"
4. Click "Create Credentials" > "OAuth client ID"
5. Set up the OAuth consent screen if prompted
6. Select "Web application" as the application type
7. Add authorized JavaScript origins (e.g., http://localhost:3000)
8. Add authorized redirect URIs (e.g., http://localhost:3000/)
9. Click "Create" and note your Client ID and Client Secret

2. Configure AWS Amplify Gen 2

First, install the AWS Amplify Gen 2 packages:

Initialize Amplify in your project:

3. Configure Authentication

The amplify/auth/resource.ts file in the code project defines the authentication configuration. Make sure to set your Google Client ID and Client Secret as environment variables:

Please make sure to add the following environment variables to your project:

Understanding auth/resource.tsin AWS Amplify Gen 2

The auth/resource.ts file is a crucial configuration file in AWS Amplify Gen 2 that defines how authentication works in your application. Let me break down this file and explain its components:

Purpose of auth/resource.ts

This file defines the authentication resources and configuration that will be deployed to AWS when you run the Amplify backend deployment. It uses the new declarative approach introduced in Amplify Gen 2, which makes it easier to configure authentication with TypeScript.

File Structure and Components

Here's the structure of the auth/resource.ts file from our example:

Let's break down each section:

1. defineAuthImport

This imports the defineAuth function from the Amplify backend package, which is used to define the authentication configuration.

2. loginWithConfiguration

This section defines how users can log in to your application:

• email: true - Allows users to sign in with their email address
• phone: false - Disables phone number authentication
• username: false - Disables username authentication
• externalProviders - Configures social login providers, in this case Google

For Google authentication:

• clientId and clientSecret are retrieved from environment variables

• scopes defines what user information your app can access:

  • profile - Access to basic profile information
  • email - Access to the user's email address
  • openid - Standard OpenID Connect scope for authentication

3. Multi-Factor Authentication (MFA)

This section configures MFA settings. In this example, MFA is turned off. Other possible values include:

• 'OPTIONAL' - Users can enable MFA but it's not required
• 'REQUIRED' - All users must set up MFA

4. Verification Configuration

This section configures the verification messages sent to users:

• emailSubject - Sets the subject line for verification emails

5. User Attributes Configuration

This section defines the user attributes that will be stored:

• email - Required and can be changed later
• name - Optional and can be changed later
• picture - Optional and can be changed later

The mutable property determines whether users can update this attribute after registration.

What Happens Behind the Scenes

When you deploy this configuration:

1. Amplify creates an Amazon Cognito User Pool with the specified settings
2. It sets up the Google identity provider integration in Cognito
3. It configures the attribute mappings between Google and your user pool
4. It creates the necessary IAM roles and policies

How This Connects to Your Frontend

In your frontend code, you'll use the Amplify client libraries to interact with this authentication configuration. The client will handle:

1. Redirecting users to Google for authentication
2. Processing the OAuth callback
3. Storing tokens securely
4. Managing the authenticated session

Benefits of the Gen 2 Approach

AWS Amplify Gen 2 offers several advantages over the previous version:

1. Type Safety: The configuration is fully typed with TypeScript
2. Declarative Syntax: The configuration is more readable and maintainable
3. Environment Variable Integration: Easy integration with environment variables
4. Simplified Deployment: The deployment process is streamlined

Would you like me to explain any specific part of this file in more detail?