OAuth2 Login with GitHub in Spring Boot

This project demonstrates OAuth2 implementation in a Spring Boot application using GitHub as the authentication provider. It covers setting up OAuth2 client configurations, creating endpoints for login/logout, and displaying user details upon successful authentication.

Project Overview

In this application, users can:

• Log in using their GitHub accounts.
• Access a customized home page displaying their GitHub profile and repository links.
• Log out securely, clearing session data.
• Revoke tokens in GitHub to test re-authorization flows.

Key Concepts

• OAuth2 Flow: We leverage GitHub as the OAuth2 provider.
• Session Management: Ensure secure sessions with Spring Security.
• User Interface (UI): Simple UI built with Thymeleaf and Bootstrap.

Prerequisites

• Java 17
• Maven 3+
• Spring Boot 3.x
• GitHub Developer Account (for creating OAuth App)

Getting Started

1. Set Up GitHub OAuth Application

Create an OAuth application on GitHub:

1. Go to GitHub Developer Settings.

2. Select New OAuth App.

3. Fill in details:

   • Application name: wish-it.com (or any other name)
   • Homepage URL: http://localhost:8080
   • Authorization callback URL: http://localhost:8080/login/oauth2/code/github

4. Once created, save the Client ID and Client Secret.

2. Clone This Repository

Clone this project repository:

git clone https://github.com//oauth2-github-demo.git cd oauth2-github-demo

3. Set Up Configuration

Open src/main/resources/application.yml and add your GitHub OAuth2 credentials:

spring: security: oauth2: client: registration: github: client-id: <YOUR_CLIENT_ID> client-secret: <YOUR_CLIENT_SECRET> scope: read:user

4. Build and Run

Use Maven to build and run the application:

mvn clean install mvn spring-boot:run

Visit http://localhost:8080/login to start the login process.

Project Structure

pom.xml

Includes the following dependencies:

• spring-boot-starter-web: Provides web application support.
• spring-boot-starter-oauth2-client: Manages OAuth2 login and authorization.
• spring-boot-starter-thymeleaf: Renders dynamic HTML templates.

application.yml

Contains configuration for OAuth2 login:

• Client ID and Client Secret from GitHub OAuth.
• Scope set to read:user for accessing basic GitHub profile information.

Security Configuration

Located in SecurityConfig.java:

• Permit Access: Sets /login and /logout as open paths.
• OAuth2 Login Setup: Defines a custom login page and redirects successful logins to /home.
• Session Invalidation: Clears session data upon logout.

Controllers

MyController.java

• /login: Displays the login page.
• /home: Fetches user details and renders them on home.html.
• /logout: Ends the session and redirects to logout.html.
• /error: Displays error information if authentication fails.

HTML Templates

1. login.html - Displays a button for GitHub login.
2. home.html - Displays user details (username, profile link, and repositories).
3. logout.html - Confirms user logout and provides a re-login option.
4. error.html - Displays error details for authentication issues.

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Usage Scenarios

1. User Login

• Access http://localhost:8080/login.
• Click on Login via GitHub.
• Upon successful authorization, users are redirected to the home page.

2. Re-login Without Re-Authorization

• After initial login, subsequent logins bypass re-authorization (session persists).

3. Token Revocation

• Revoke tokens from GitHub to test re-authorization.
• On re-login, users will need to authorize the app again.

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Example Commands

Create Spring Boot App from CLI

To create a Spring Boot application directly from the command line:

Windows (PowerShell)

Invoke-WebRequest -Uri "https://start.spring.io/starter.zip?name=oauth2-demo&dependencies=web,thymeleaf,oauth2-client&type=maven-project" -OutFile oauth2-demo.zip

Mac/Linux (Terminal)

curl -o oauth2-demo.zip "https://start.spring.io/starter.zip?name=oauth2-demo&dependencies=web,thymeleaf,oauth2-client&type=maven-project"

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Screenshots

Include screenshots of each page:

1. Login Page
2. Home Page with User Details
3. Logout Confirmation Page
4. Error Page

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Future Enhancements

• Support for additional OAuth2 providers (Google, Facebook).
• Adding detailed error handling and user-friendly messages.
• Implementing authorization flows with custom roles and scopes.

Contributing

If you'd like to contribute, please fork the repository and create a pull request.