flyer-crawler.projectium.com/AUTHENTICATION.md

Authentication Setup

Flyer Crawler supports OAuth authentication via Google and GitHub. This guide walks through configuring both providers.

---

Google OAuth

Step 1: Create 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. Select Web application as the application type

Step 2: Configure Authorized Redirect URIs

Add the callback URL where Google will redirect users after authentication:

Environment	Redirect URI
Development	http://localhost:3001/api/auth/google/callback
Production	https://your-domain.com/api/auth/google/callback

Step 3: Save Credentials

After clicking Create, you'll receive:

• Client ID
• Client Secret

Store these securely as environment variables:

• GOOGLE_CLIENT_ID
• GOOGLE_CLIENT_SECRET

---

GitHub OAuth

Step 1: Create OAuth App

1. Go to your GitHub Developer Settings
2. Navigate to OAuth Apps
3. Click New OAuth App

Step 2: Fill in Application Details

Field	Value
Application name	Flyer Crawler (or your preferred name)
Homepage URL	http://localhost:5173 (dev) or your production URL
Authorization callback URL	http://localhost:3001/api/auth/github/callback

Step 3: Save GitHub Credentials

After clicking Register application, you'll receive:

• Client ID
• Client Secret

Store these securely as environment variables:

• GITHUB_CLIENT_ID
• GITHUB_CLIENT_SECRET

---

Environment Variables Summary

Variable	Description
GOOGLE_CLIENT_ID	Google OAuth client ID
GOOGLE_CLIENT_SECRET	Google OAuth client secret
GITHUB_CLIENT_ID	GitHub OAuth client ID
GITHUB_CLIENT_SECRET	GitHub OAuth client secret
JWT_SECRET	Secret for signing authentication tokens

---

Production Considerations

When deploying to production:

1. Update redirect URIs in both Google Cloud Console and GitHub OAuth settings to use your production domain
2. Use HTTPS for all callback URLs in production
3. Store secrets securely using your CI/CD platform's secrets management (e.g., Gitea repository secrets)

---

Troubleshooting

"redirect_uri_mismatch" Error

The callback URL in your OAuth provider settings doesn't match what the application is sending. Verify:

• The URL is exactly correct (no trailing slashes, correct port)
• You're using the right environment (dev vs production URLs)

"invalid_client" Error

The Client ID or Client Secret is incorrect. Double-check your environment variables.

---

Related Documentation

• Installation Guide - Local development setup
• Deployment Guide - Production deployment