YouTube Clone - Flask Implementation

A full-featured video sharing platform with YouTube-like functionality built with Flask, React, and modern web technologies.

Features

Authentication & Authorization

• Email/password registration and login
• Password reset and email verification
• JWT-based sessions
• Role-based access control (user, moderator, admin)

User Profiles & Channels

• User profiles with avatars
• Channel pages with banners and descriptions
• Subscribe/unsubscribe functionality

Video Management

• Resumable/chunked video uploads with progress tracking
• Server-side transcoding to multiple resolutions (1080p, 720p, 480p, 360p)
• Automatic and custom thumbnail generation
• Metadata extraction (duration, resolution, bitrate)

Storage & Streaming

• Local file storage for development
• S3-compatible storage (AWS S3 for production)
• HLS streaming with master playlists
• Signed short-lived URLs for secure access

Playback Experience

• Custom HTML5/JS player
• Resolution selector
• Captions/subtitles toggle
• Playback speed control
• Picture-in-Picture support
• Autoplay next video

Social & Engagement

• Like/dislike functionality
• Threaded comments with replies
• Edit/delete for content owners
• Report system for moderation
• Watch later playlists
• User playlists

Search & Discovery

• Full-text search on titles, descriptions, and tags
• Trending videos feed
• Recommended videos based on subscriptions
• Subscription feed

Notifications

• In-app notifications for new uploads and comment replies

Admin Dashboard

• Content moderation
• User management
• Report handling
• Analytics dashboard

Tech Stack

Frontend

• React with TypeScript
• Tailwind CSS for styling
• Responsive design for all device sizes

Backend

• Flask with Blueprints
• SQLAlchemy ORM
• Alembic for database migrations
• Flask-JWT-Extended for authentication
• Celery with Redis for background tasks

Workers

• Celery workers for video processing
• FFmpeg for transcoding and thumbnail generation

Database

• PostgreSQL (or SQLite for local development)

Storage

• Local file system for development
• AWS S3 for production

Project Structure

youtube-clone/
├── backend/           # Flask API server
├── frontend/          # React frontend
├── worker/            # Celery workers for video processing
├── docs/              # Documentation
└── README.md          # This file

Getting Started (Without Docker)

Prerequisites

• Python 3.8+
• Node.js 14+
• PostgreSQL (optional, can use SQLite for development)
• Redis
• FFmpeg
• Git

Backend Setup

1. Navigate to the backend directory:

   cd backend

2. Create a virtual environment:

   python -m venv venv
   source venv/bin/activate  # On Windows: venv\Scripts\activate

3. Install dependencies:

   pip install -r requirements.txt

4. Copy the example environment file:

   cp .env.example .env

5. Update the .env file with your local configuration:

   # For local development with SQLite
   DATABASE_URL=sqlite:///youtube.db
   
   # For PostgreSQL
   # DATABASE_URL=postgresql://username:password@localhost:5432/youtube_dev

6. Run database migrations:

   flask db upgrade

7. Start the backend server:

   flask run

Frontend Setup

1. Navigate to the frontend directory:

   cd frontend

2. Install dependencies:

   npm install

3. Start the development server:

   npm start

Worker Setup

1. Navigate to the worker directory:

   cd worker

2. Create a virtual environment:

   python -m venv venv
   source venv/bin/activate  # On Windows: venv\Scripts\activate

3. Install dependencies:

   pip install -r requirements.txt

4. Start the worker:

   celery -A worker worker --loglevel=info

Environment Variables

The application uses environment variables for configuration. See .env.example for all available options.

For local development without Docker, you'll need to:

1. Install PostgreSQL or use SQLite
2. Install Redis server
3. Install FFmpeg
4. Configure the .env file appropriately

Development

Project Structure Details

Backend (backend/)

• app.py - Main Flask application
• config.py - Configuration settings
• requirements.txt - Python dependencies
• app/ - Application modules
  • auth/ - Authentication and user management
  • videos/ - Video management and processing
  • users/ - User and channel management
  • admin/ - Admin and moderation features
  • models.py - Database models
• migrations/ - Database migrations
• tests/ - Unit and integration tests
• docs/ - API documentation

Frontend (frontend/)

• package.json - Node.js dependencies
• src/ - Source code
• public/ - Static assets

Worker (worker/)

• worker.py - Celery worker implementation
• requirements.txt - Python dependencies

Database Migrations

The application uses Alembic for database migrations:

# Generate a new migration
flask db migrate -m "Description of changes"

# Apply migrations
flask db upgrade

API Documentation

API documentation is available in backend/docs/api.md or by accessing /api/docs when the backend is running.

Testing

Backend Tests

# Run all tests
pytest

# Run specific test file
pytest tests/test_auth.py

Test Coverage

The project aims for >70% test coverage for critical backend functionality.

Deployment

Production Deployment

See docs/deployment.md for detailed deployment instructions.

Environment Differences

• Development: Uses local file storage, SQLite or local PostgreSQL and Redis
• Production: Uses AWS S3 for storage, managed PostgreSQL and Redis

Architecture

See docs/architecture.md for detailed architecture diagrams and explanations.

Contributing

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Write tests for new functionality
5. Run all tests to ensure nothing is broken
6. Submit a pull request

License

This project is licensed under the MIT License - see the LICENSE file for details.

Support

For support, please open an issue on the GitHub repository.