Fact Checker

Tagline: Let's Make Difference Between Fact and Fiction

A comprehensive web application for fact-checking multimedia content (video, audio, image) using Google Cloud Services and Gemini 2.5 Flash with Search Grounding.

🎯 Features

• Multi-format Support: Upload and analyze videos, audio files, and images
• Speech-to-Text: Automatic audio extraction from videos and transcription using Google Cloud Speech-to-Text
• AI-Powered Fact-Checking: Leverages Gemini 2.5 Flash with Google Search Grounding for accurate verification
• Citation & Evidence: Displays sources and citations for fact-check results
• User History: Track all your past fact-checks with admin comments
• Admin Dashboard: Complete oversight of all users and fact-checks with commenting functionality
• Role-Based Access: Separate user and admin interfaces

📁 Project Structure

fact-checker/
├── .env                          # Environment variables
├── gcp-credentials.json          # Google Cloud credentials (not included)
├── package.json                  # Root package scripts
├── README.md                     # This file
├── Project_Plan.md               # Detailed project plan
│
├── Data/                         # CSV database and uploads
│   ├── users.csv
│   ├── fact_checks.csv
│   ├── admin_comments.csv
│   └── uploads/
│       ├── videos/
│       ├── audio/
│       └── images/
│
├── backend/                      # FastAPI backend
│   ├── main.py
│   ├── requirements.txt
│   ├── config/
│   ├── models/
│   ├── routes/
│   ├── services/
│   ├── utils/
│   └── middleware/
│
└── frontend/                     # React + TypeScript + Vite
    ├── index.html
    ├── package.json
    ├── vite.config.ts
    ├── tsconfig.json
    └── src/
        ├── main.tsx
        ├── App.tsx
        ├── components/
        ├── pages/
        ├── context/
        ├── services/
        ├── types/
        ├── utils/
        └── hooks/

🚀 Quick Start

Prerequisites

• Python 3.8+
• Node.js 18+
• FFmpeg (for video processing)
• Google Cloud Account with Speech-to-Text API enabled
• Gemini API Key from Google AI Studio

Installation

1. Clone the repository

   git clone <repository-url>
   cd Fact_Checker

2. Set up environment variables

   Copy the .env file and fill in your API keys:

   # Edit .env file with your credentials
   GEMINI_API_KEY=your_gemini_api_key_here
   GCP_PROJECT_ID=your_gcp_project_id
   GCP_CREDENTIALS_PATH=./gcp-credentials.json
   JWT_SECRET_KEY=your_secret_key_here

3. Download GCP Service Account JSON

   • Go to Google Cloud Console
   • Create a service account with Speech-to-Text API access
   • Download the JSON key file
   • Save it as gcp-credentials.json in the root directory

4. Install dependencies

   # Install backend dependencies
   cd backend
   pip install -r requirements.txt
   
   # Install frontend dependencies
   cd ../frontend
   npm install
   
   # Or install all at once from root
   cd ..
   npm install
   npm run install:all

5. Install FFmpeg (if not already installed)

   • Ubuntu/Debian: sudo apt-get install ffmpeg
   • macOS: brew install ffmpeg
   • Windows: Download from ffmpeg.org

Running the Application

Development Mode

Option 1: Run both servers concurrently (recommended)

npm run dev

Option 2: Run servers separately

# Terminal 1 - Backend
npm run dev:backend
# or
cd backend && python main.py

# Terminal 2 - Frontend
npm run dev:frontend
# or
cd frontend && npm run dev

The application will be available at:

• Frontend: http://localhost:5173
• Backend API: http://localhost:8000
• API Documentation: http://localhost:8000/api/docs

Production Mode

# Build frontend
npm run build:frontend

# Start backend
npm run start:backend

# Start frontend preview
npm run start:frontend

👤 User Accounts

Default Admin Account

• Email: admin@factchecker.com
• Password: admin123
• Role: Admin

Creating New Users

Users can register through the login page or be added directly to Data/users.csv.

📖 Usage Guide

For Users

1. Login

   • Navigate to http://localhost:5173
   • Enter your email and password
   • Select "User" role
   • Click Login

2. Upload Content

   • Select content type (Video, Audio, or Image)
   • Drag & drop or browse to select file
   • Click "Upload and Fact Check"

3. View Results

   • See extracted text (for video/audio)
   • Read AI-powered fact-check analysis
   • Explore citations and sources
   • View admin comments if available

4. Check History

   • Navigate to History page
   • View all past fact-checks
   • Click on any item to see full details

For Admins

1. Login as Admin

   • Use admin credentials
   • Select "Admin" role

2. View All Users

   • See all registered users
   • Click on a user to view their fact-checks

3. Review Fact-Checks

   • Browse through user submissions
   • Read detailed analysis and results

4. Add Comments

   • Open any fact-check
   • Add administrative comments
   • Users can see these comments in their history

🔧 Configuration

Backend Configuration (.env)

# API Keys
GEMINI_API_KEY=your_key_here
GCP_PROJECT_ID=your_project_id
GCP_CREDENTIALS_PATH=./gcp-credentials.json

# JWT Settings
JWT_SECRET_KEY=your_secret_key
JWT_ALGORITHM=HS256
ACCESS_TOKEN_EXPIRE_MINUTES=1440

# Server Ports
BACKEND_PORT=8000
FRONTEND_PORT=5173

# CORS
CORS_ORIGINS=http://localhost:5173,http://localhost:3000

# File Upload Limits
MAX_FILE_SIZE_MB=100

Frontend Configuration (frontend/.env.local)

VITE_API_BASE_URL=http://localhost:8000

🛠️ Technology Stack

Backend

• FastAPI: Modern Python web framework
• Google Cloud Speech-to-Text: Audio transcription
• Gemini 2.5 Flash: AI-powered fact-checking with Search Grounding
• FFmpeg: Video/audio processing
• Pandas: CSV database operations
• JWT: Authentication

Frontend

• React 18: UI framework
• TypeScript: Type-safe JavaScript
• Vite: Fast build tool
• React Router: Navigation
• Axios: HTTP client
• Context API: State management

Storage

• CSV Files: Lightweight database
• Local File System: Media storage

📚 API Documentation

Once the backend is running, visit http://localhost:8000/api/docs for interactive API documentation (Swagger UI).

Key Endpoints

Authentication

• POST /api/auth/login - User/Admin login
• POST /api/auth/register - User registration
• POST /api/auth/logout - Logout

File Upload

• POST /api/upload/video - Upload video file
• POST /api/upload/audio - Upload audio file
• POST /api/upload/image - Upload image file

Fact-Checking

• POST /api/fact-check/process - Process uploaded file
• GET /api/fact-check/result/{id} - Get fact-check result

History

• GET /api/history/user - Get current user's history
• GET /api/history/details/{id} - Get specific fact-check details

Admin

• GET /api/admin/users - Get all users (admin only)
• GET /api/admin/fact-checks - Get all fact-checks (admin only)
• POST /api/admin/comment - Add comment to fact-check
• GET /api/admin/comments/{id} - Get comments for fact-check

🔒 Security

• JWT-based authentication
• Role-based access control
• Password hashing with bcrypt
• File upload validation
• CORS protection
• Input sanitization

🐛 Troubleshooting

Common Issues

1. FFmpeg not found

   • Install FFmpeg: See installation instructions above
   • Verify installation: ffmpeg -version

2. GCP Authentication Error

   • Ensure gcp-credentials.json is in the root directory
   • Verify service account has Speech-to-Text API access
   • Check GCP_CREDENTIALS_PATH in .env

3. Gemini API Error

   • Verify GEMINI_API_KEY is correct
   • Check API quota and limits
   • Ensure you're using Gemini 2.0 Flash Exp or compatible model

4. Port Already in Use

   • Change ports in .env file
   • Kill existing processes using the ports

5. CORS Errors

   • Update CORS_ORIGINS in .env
   • Ensure frontend URL is in the allowed origins

📝 Development Notes

• CSV files serve as a simple database for development
• For production, consider migrating to PostgreSQL or MongoDB
• File uploads are stored locally; consider cloud storage for production
• Default admin password should be changed in production

🤝 Contributing

1. Fork the repository
2. Create a feature branch
3. Commit your changes
4. Push to the branch
5. Create a Pull Request

📄 License

MIT License - feel free to use this project for learning and development.

👥 Support

For issues, questions, or suggestions:

• Check the API documentation at /api/docs
• Review Project_Plan.md for detailed architecture
• Open an issue on GitHub

🎉 Acknowledgments

• Google Cloud Platform for Speech-to-Text API
• Google AI Studio for Gemini API
• FastAPI and React communities
• All open-source contributors

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Built with ❤️ for truth and accuracy