High-performance WebSockets for your Flask apps powered by uWSGI. Inspired by Flask-Sockets.
from flask import Flask
from flask.ext.uwsgi_websocket import WebSocket
app = Flask(__name__)
ws = WebSocket(app)
@ws.route('/echo')
def echo(ws):
while True:
msg = ws.receive()
ws.send(message)
if __name__ == '__main__':
app.run(debug=True, threads=16)To install Flask-uWSGI-WebSocket, simply:
$ pip install Flask-uWSGI-WebSocket
You can use uWSGI's built-in HTTP router to get up and running quickly:
$ uwsgi --master --http :8080 --http-websockets --wsgi-file app.py
...or call app.run, passing uwsgi any arguments you like:
app.run(debug=True, host='localhost', port=8080, master=true, processes=8)
uWSGI supports several concurrency models, in particular it has nice support
for Gevent. If you want to use Gevent, import
flask.ext.uwsgi_websocket.GeventWebSocket and configure uWSGI to use the
gevent loop engine:
$ uwsgi --master --http :8080 --http-websockets --gevent 100 --wsgi-file app.py
...or:
app.run(debug=True, gevent=100)
For production you'll probably want to run uWSGI behind Haproxy or nginx of course, instead of using the built-int HTTP router. Explore the uWSGI documentation for more detail.
It's possible to take advantage of Flask's interactive debugger by installing
werkzeug's DebuggedApplication middleware:
from werkzeug.debug import DebuggedApplication app.wsgi_app = DebuggedApplication(app.wsgi_app, True)
...and running uWSGI with only a single worker:
$ uwsgi --master --http :8080 --http-websockets --wsgi-file --workers 1 --threads 8 app.py
If you use app.run(debug=True), Flask-uWSGI-Websocket will do this
automatically for you.
Automatically performs WebSocket handshake for you, but otherwise only exposes the uWSGI WebSocket API.
websocket.recv() (alias websocket.receive())
websocket.recv_nb()
websocket.send(msg)
websocket.send_binary(msg)
websocket.recv_nb()
websocket.send_from_sharedarea(id, pos)
websocket.send_binary_from_sharedarea(id, pos)
Fancier WebSocket abstraction that takes advantage of Gevent loop engine. Route handlers are spawned in their own greenlets and able to easily send messages to each othek.
websocket.receive()
websocket.send()
websocket.close()
websocket.connected