Flask-SocketIO

Flask-SocketIO enables low-latency, real-time, bi-directional communication for Flask applications using the Socket.IO protocol.

Flask-SocketIO is the essential extension for integrating Socket.IO into your Python Flask projects, providing robust support for event-based, bi-directional communication. It uses WebSockets as the primary transport mechanism, automatically falling back to long-polling for broader client compatibility. The package handles the complexities of asynchronous services, preferring high-performance options like `eventlet` or `gevent` over the standard Werkzeug development server for production. Developers define event handlers using the simple `@socketio.on()` decorator, facilitating the creation of features like live chat, real-time notifications, and collaborative editing tools. To deploy, you replace the standard `app.run()` with `socketio.run(app)`, ensuring the application leverages the full power of persistent connections.

https://flask-socketio.readthedocs.io/en/latest/