Chapter 35: OAuth2 Integration in C

Google, GitHub, Discord login. In this chapter, you will learn oauth2 integration in depth with C code examples, explanations, and best practices.

Overview

This chapter covers oauth2 integration for Kungfu.js developers using C. We will start with the basics, move through practical examples, and end with advanced techniques and common pitfalls.

Why This Matters

Understanding oauth2 integration is essential because it is a core part of building web applications. Every real-world app needs to handle google, github, discord login. Skipping this chapter would leave a gap in your knowledge that would cause problems later.

Code Example

Here is how authentication works in C:

use kungfu_core::auth_ext::{OAuth2Config, OAuth2Provider};

let config = OAuth2Config {
    provider: OAuth2Provider::GitHub,
    client_id: "your-client-id".into(),
    client_secret: "your-secret".into(),
    redirect_uri: "http://localhost:3000/callback".into(),
    scopes: vec!["user:email".into()],
};

// Redirect user to:
let url = config.authorization_url("random-state");

Security Best Practices

Never store passwords in plain text. Kungfu.js uses Argon2id, which is the winner of the Password Hashing Competition. It is designed to be resistant to GPU and ASIC attacks.

JWT tokens should have an expiration time. A good default is 1 hour for access tokens and 7 days for refresh tokens. Kungfu.js validates the expiration automatically.

Common Mistakes

  • Not reading the documentation: Always check the API reference when something does not work as expected.
  • Skipping security: Never disable the default middleware unless you have a very good reason. Security is not optional.
  • Not testing: Write tests for your handlers. Kungfu.js makes this easy with the built-in test utilities.

Summary

In this chapter, you learned about oauth2 integration in C. You saw code examples, understood how things work under the hood, and learned about common mistakes to avoid.

What is Next?

In chapter 36, we will cover WebSocket Basics: Real-time bidirectional communication.

Previous: Role-Based Access ControlNext: WebSocket Basics