A Val Town service for handling GitHub OAuth authentication with redirect support for external applications.

• GitHub OAuth sign-in flow
• JWT token generation for authenticated users
• Redirect support for external applications
• Secure token validation
• User profile retrieval

1. Create a GitHub OAuth App:

   • Go to GitHub Settings > Developer settings > OAuth Apps
   • Create a new OAuth App
   • Set Authorization callback URL to: https://[your-val-url]/auth/callback

2. Set environment variables in Val Town:

   • GITHUB_CLIENT_ID: Your GitHub OAuth app client ID
   • GITHUB_CLIENT_SECRET: Your GitHub OAuth app client secret
   • JWT_SECRET: A secure random string for signing JWT tokens

1. Redirect users to: https://[your-val-url]/auth/signin?redirect_uri=[your-app-url]
2. Users will be redirected to GitHub for authentication
3. After successful auth, users are redirected back to your app with a token: [your-app-url]?token=[jwt-token]

Make a GET request to: https://[your-val-url]/auth/validate?token=[jwt-token]

Returns user profile if token is valid.

• GET /auth/signin - Initiate GitHub OAuth flow
• GET /auth/callback - Handle GitHub OAuth callback
• GET /auth/validate - Validate JWT token and return user info
• GET / - Auth page UI

• /backend/index.ts - Main Hono server with OAuth routes
• /frontend/index.html - Auth page UI
• /shared/types.ts - Shared TypeScript types