django中实时获取当前在线人数

settings.py

# 设置session过期时间
SESSION_COOKIE_AGE = 60 * 30  # 30分钟

views.py

    def get_all_login_user():
        SQL = """
              SELECT  * FROM `django_session` WHERE expire_date >= NOW() GROUP BY session_data; 
        # 根据session值是否重复判断用户是否在线  不太完善
        sessions = Session.objects.filter(expire_date__gte=datetime.now())
        user_list = []
        # 获取session中的用户id
        for session in sessions:
            data = session.get_decoded()
            print(data)
            user_list.append(data.get('_auth_user_id', None))
        print(user_list, 66666666)
        return user_list

user/views.py

@accept_websocket
def get_user_list(request):
    if request.is_websocket():
        message = request.websocket.wait()
        while True:
            if message:
                user_list = BllUser().get_all_login_user()
                request.websocket.send(str(len(user_list)))
                time.sleep(10)

index.html

<div class="col-md-offset-1" style="display: inline-block;line-height: 48px;color:orange">
        当前在线人数: <span id="online_number">0</span>
    // 实时获取当前在线用户人数
    var socket = new WebSocket("ws:" + window.location.host + "/user/get_user_list/");
            socket.onopen = function () {
                console.log('WebSocket open');//成功连接上Websocket
                socket.send('adasdasda。。。。');//发送数据到服务端
            socket.onmessage = function (e) {
                $('#online_number').text(e.data)
            socket.onclose=function(e){