WebSocket

简单理解WebSocket:因为 HTTP 协议有一个缺陷----通信只能由客户端发起。而WebSocket的最大特点就是，服务器可以主动向客户端推送信息，客户端也可以主动向服务器发送信息，是真正的双向平等对话，属于服务器推送技术的一种。

WebSocket模板

import json

from flask import Flask,request,render_template

from geventwebsocket.handler import WebSocketHandler
from gevent.pywsgi import WSGIServer
from geventwebsocket.websocket import WebSocket

app = Flask(__name__)

user_socket_dict = {}

@app.route("/conn_ws/<user_nick>")
def ws_app(user_nick):

    user_socket = request.environ.get("wsgi.websocket")  # type:WebSocket
    user_socket_dict[user_nick] = user_socket
    print(len(user_socket_dict),list(user_socket_dict.keys()))

    while True:
        msg = user_socket.receive()
        # {from_user:"alexDSB",to_user:"YWB",message:"666"}
        msg_dict = json.loads(msg)
        to_user = msg_dict.get("to_user")
        to_user_socket = user_socket_dict.get(to_user)
        to_user_socket.send(msg)

        #
        # for usocket in  user_socket_list:
        #     usocket.send(msg)

        # user_socket.send(msg)


if __name__ == '__main__':

    http_serv = WSGIServer(("0.0.0.0",9527),app,handler_class=WebSocketHandler)
    http_serv.serve_forever()