Learn TORNADO-REST with Real Code Examples

Tornado provides an asynchronous, non-blocking web server and framework for Python.

Supports long-lived connections such as WebSockets, making it ideal for real-time apps.

Includes routing, request handlers, and asynchronous HTTP client features.

Handles thousands of concurrent connections with minimal overhead.

Flexible and lightweight, allowing integration with other Python libraries.

Asynchronous HTTP server

RequestHandler classes for routing

WebSocketHandler for persistent connections

Integration with Python’s asyncio

Flexible URL routing and parameter handling

RequestHandler - class handling HTTP requests

WebSocketHandler - class for WebSocket connections

Application - maps URLs to handlers

IOLoop - core async event loop

Coroutine - async function using async/await

app.py - main application and server entry point

handlers/ - HTTP and WebSocket handlers

services/ - optional business logic

static/ - optional static files

requirements.txt - dependencies

Define request handlers for API endpoints

Set up URL routing in Application

Implement async methods using coroutines

Integrate WebSocketHandlers if needed

Run the server on IOLoop and test endpoints

Beginner: basic hello-world endpoint

Intermediate: CRUD REST API with async handlers

Advanced: WebSocket chat server

Expert: high-concurrency real-time microservices

Enterprise: IoT or streaming APIs with async processing

Tornado vs Flask: Tornado async and high-concurrency, Flask synchronous and simple

Tornado vs FastAPI: FastAPI more structured, Tornado lower-level async

Tornado vs Django REST Framework: DRF more feature-rich, Tornado lightweight and async

Tornado vs Sanic: Both async; Sanic higher-level API helpers

Tornado vs Node.js frameworks: Python ecosystem vs JS event loop

2009 - Initial release by FriendFeed engineers

2010 - Tornado 1.x stable with HTTP server

2013 - Tornado 3.x async enhancements

2017 - Tornado 5.x Python 3-only support

2025 - Latest Tornado 6.x with modern async/await support

RequestHandler - class handling HTTP requests

WebSocketHandler - class for WebSocket connections

Application - maps URLs to handlers

IOLoop - async event loop for non-blocking operations

Coroutine - async function using async/await