tasko/GOOGLE_OAUTH_SETUP.md

Google OAuth Setup Guide

Prerequisites

1. A Google Cloud Platform account
2. A project created in Google Cloud Console

Step 1: Create OAuth 2.0 Credentials

1. Go to Google Cloud Console
2. Select your project (or create a new one)
3. Navigate to APIs & Services > Credentials
4. Click Create Credentials > OAuth 2.0 Client ID
5. If prompted, configure the OAuth consent screen:
   • Choose External user type
   • Fill in the required fields:
     • App name: Tasko
     • User support email: Your email
     • Developer contact information: Your email
   • Add scopes (optional): userinfo.email, userinfo.profile
   • Add test users if needed
6. Select Application type: Web application
7. Add Authorized redirect URIs:
   • For local development: http://localhost:8000/auth/google/callback
   • For production: https://your-domain.com/auth/google/callback
8. Click Create
9. Copy the Client ID and Client Secret

Step 2: Configure Backend

1. Copy .env.example to .env in the backend directory:

   cd backend
   cp .env.example .env
   

2. Edit .env and add your Google OAuth credentials:

   GOOGLE_CLIENT_ID=your_client_id_here.apps.googleusercontent.com
   GOOGLE_CLIENT_SECRET=your_client_secret_here
   GOOGLE_REDIRECT_URI=http://localhost:8000/auth/google/callback
   FRONTEND_URL=http://localhost:5173
   

3. For production, update the URLs:

   GOOGLE_REDIRECT_URI=https://api.tasko.dvirlabs.com/auth/google/callback
   FRONTEND_URL=https://tasko.dvirlabs.com
   

Step 3: Install Dependencies

cd backend
pip install -r requirements.txt

Step 4: Test the Setup

1. Start the backend server:

   cd backend
   uvicorn main:app --reload
   

2. Start the frontend:

   cd frontend
   npm run dev
   

3. Open your browser and navigate to the frontend URL

4. Click "Continue with Google" button

5. Complete the Google authentication flow

Features Implemented

1. Case-Insensitive Username Login

• Users can now login with usernames in any case (e.g., "Dvir", "dvir", "DVIR" all work)
• Registration checks for existing usernames case-insensitively to prevent duplicates

2. Google OAuth Integration

• Users can sign up and login using their Google account
• New users are automatically created with:
  • Username derived from email (before @)
  • Email from Google account
  • Default task lists (Personal, Work, Shopping)
• Existing users (matched by email) can login with Google
• Seamless redirect back to the application after authentication

Troubleshooting

"redirect_uri_mismatch" Error

• Ensure the redirect URI in Google Cloud Console exactly matches the one in your .env file
• Include the protocol (http/https), domain, port, and full path

"Access blocked" Error

• Add your email as a test user in the OAuth consent screen
• If published, ensure your app is verified by Google

"Invalid credentials" Error

• Check that your GOOGLE_CLIENT_ID and GOOGLE_CLIENT_SECRET are correct
• Ensure there are no extra spaces or quotes in the .env file

Security Notes

1. Never commit your .env file to version control
2. Keep your GOOGLE_CLIENT_SECRET secure
3. Use HTTPS in production
4. Regularly rotate your OAuth credentials
5. Review and limit the OAuth scopes to only what's needed