python-socketio

Python implementation of the `Socket.IO`_ realtime server.

Features

• Fully compatible with the Javascript, Swift, C++ and Java official Socket.IO clients, plus any third party clients that comply with the Socket.IO specification.
• Compatible with Python 2.7 and Python 3.3+.
• Supports large number of clients even on modest hardware when used with an asynchronous server based on asyncio, eventlet or gevent. For development and testing, any WSGI complaint multi-threaded server can also be used.
• Includes a WSGI middleware that integrates Socket.IO traffic with standard WSGI applications.
• Broadcasting of messages to all connected clients, or to subsets of them assigned to "rooms".
• Optional support for multiple servers, connected through a messaging queue such as Redis or RabbitMQ.
• Send messages to clients from external processes, such as Celery workers or auxiliary scripts.
• Event-based architecture implemented with decorators that hides the details of the protocol.
• Support for HTTP long-polling and WebSocket transports.
• Support for XHR2 and XHR browsers.
• Support for text and binary messages.
• Support for gzip and deflate HTTP compression.
• Configurable CORS responses, to avoid cross-origin problems with browsers.

Example

The following eample application uses the aiohttp framework for asyncio:

from aiohttp import web
import socketio

sio = socketio.AsyncServer()
app = web.Application()
sio.attach(app)

async def index(request):
    """Serve the client-side application."""
    with open('index.html') as f:
        return web.Response(text=f.read(), content_type='text/html')

@sio.on('connect', namespace='/chat')
def connect(sid, environ):
    print("connect ", sid)

@sio.on('chat message', namespace='/chat')
async def message(sid, data):
    print("message ", data)
    await sio.emit('reply', room=sid)

@sio.on('disconnect', namespace='/chat')
def disconnect(sid):
    print('disconnect ', sid)

app.router.add_static('/static', 'static')
app.router.add_get('/', index)

if __name__ == '__main__':
    web.run_app(app)

And below is a similar example, using Flask to serve the client application. This example is compatible with Python 2.7 and Python 3.3+:

import socketio
import eventlet
import eventlet.wsgi
from flask import Flask, render_template

sio = socketio.Server()
app = Flask(__name__)

@app.route('/')
def index():
    """Serve the client-side application."""
    return render_template('index.html')

@sio.on('connect', namespace='/chat')
def connect(sid, environ):
    print("connect ", sid)

@sio.on('chat message', namespace='/chat')
def message(sid, data):
    print("message ", data)
    sio.emit('reply', room=sid)

@sio.on('disconnect', namespace='/chat')
def disconnect(sid):
    print('disconnect ', sid)

if __name__ == '__main__':
    # wrap Flask application with engineio's middleware
    app = socketio.Middleware(sio, app)

    # deploy as an eventlet WSGI server
    eventlet.wsgi.server(eventlet.listen(('', 8000)), app)

Resources

• Documentation
• PyPI