Tornado 实现的 WebSocket 简单例子

Server 部分，主要就是继承 WebSocketHandler 实现了个 WebSocket Handler

import logging
import tornado.web
import tornado.websocket
import tornado.ioloop
import tornado.options

from tornado.options import define, options

define("port", default=3000, help="run on the given port", type=int)


class Application(tornado.web.Application):
    def __init__(self):
        handlers = [(r"/", MainHandler)]
        settings = dict(debug=True)
        tornado.web.Application.__init__(self, handlers, **settings)


class MainHandler(tornado.websocket.WebSocketHandler):
    def check_origin(self, origin):
        return True

    def open(self):
        logging.info("A client connected.")

    def on_close(self):
        logging.info("A client disconnected")

    def on_message(self, message):
        logging.info("message: {}".format(message))


def main():
    tornado.options.parse_command_line()
    app = Application()
    app.listen(options.port)
    tornado.ioloop.IOLoop.instance().start()


if __name__ == "__main__":
    main()

Client 部分

#!/usr/bin/env python
# -*- coding: utf-8 -*-

from tornado.ioloop import IOLoop, PeriodicCallback
from tornado import gen
from tornado.websocket import websocket_connect


class Client(object):
    def __init__(self, url, timeout):
        self.url = url
        self.timeout = timeout
        self.ioloop = IOLoop.instance()
        self.ws = None
        self.connect()
        PeriodicCallback(self.keep_alive, 20000).start()
        self.ioloop.start()

    @gen.coroutine
    def connect(self):
        print("trying to connect")
        try:
            self.ws = yield websocket_connect(self.url)
        except Exception as e:
            print("connection error")
        else:
            print("connected")
            self.run()

    @gen.coroutine
    def run(self):
        while True:
            msg = yield self.ws.read_message()
            if msg is None:
                print("connection closed")
                self.ws = None
                break

    def keep_alive(self):
        if self.ws is None:
            self.connect()
        else:
            self.ws.write_message("keep alive")


if __name__ == "__main__":
    client = Client("ws://localhost:3000", 5)

运行 Server 和 Clinet 之后输出如下：

• Server 部分

[I 220805 10:49:12 server:27] A client connected.
[I 220805 10:49:32 server:33] message: keep alive
[I 220805 10:49:52 server:33] message: keep alive
[I 220805 10:50:12 server:33] message: keep alive
[I 220805 10:50:13 server:30] A client disconnected

• Client 部分

trying to connect
connected