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 (sanic and aiohttp), eventlet or gevent. For development and testing, any WSGI compliant 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 example 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