In the previous article, we explored the fundamentals of OAuth2 and OpenID Connect. Now it's time to integrate Google Login into a Spring Boot application using Spring Security 7. This enables users to authenticate using their Google accounts without creating a separate username and password for your application.
Google acts as the Authorization Server, while your Spring Boot application acts as the OAuth2 Client.
Step 1: Add the Required Dependency
Spring Security provides built-in support for OAuth2 Client.
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-oauth2-client</artifactId>
</dependency>This starter includes everything required to handle the OAuth2 Authorization Code Flow.
Step 2: Create an OAuth Client
Go to the Google Cloud Console and create a new project. Enable the Google Identity API, configure the OAuth consent screen, and create OAuth 2.0 credentials.
Google will generate two important values:
Client ID
Client Secret
These credentials uniquely identify your application when communicating with Google's authentication servers.
Step 3: Configure Spring Boot
Add the following configuration to your application.yml file:
spring:
security:
oauth2:
client:
registration:
google:
client-id: YOUR_CLIENT_ID
client-secret: YOUR_CLIENT_SECRET
scope:
- openid
- profile
- emailThe requested scopes allow your application to access the user's basic profile information and verified email address.
Step 4: Start the Authentication Flow
When a user visits:
/oauth2/authorization/googleSpring Security automatically redirects the user to Google's login page.
After successful authentication and user consent, Google redirects the user back to your application with an authorization code. Spring Security exchanges this code for an access token and an ID token, authenticating the user automatically.
Production Best Practices
Never hardcode the Client ID or Client Secret in your source code.
Store sensitive credentials in environment variables or a secure secrets manager.
Always use HTTPS in production environments.
Request only the OAuth scopes your application actually requires.
Summary
In this article, we configured Google OAuth2 Login using Spring Security 7 and Spring Boot 4. We learned how to create OAuth credentials, configure the application, and understand the authentication flow. In the next part, we will customize the OAuth2 login process by implementing a CustomOAuth2UserService, storing users in a database and generating JWT tokens after successful social authentication.
