在flask中使用websocket-实时消息推送

- flask默认使用wsgi支持http协议，如需使用websocket需要安装gevent-websocket模块，http，websocket协议都可以支持

　　Django应用：channel
　　Tornado应用：自己有

　pip3 install gevent-websocket

app.py

from flask import Flask,request,render_template,redirect,session
import uuid
from geventwebsocket.handler import WebSocketHandler
from gevent.pywsgi import WSGIServer
import json


app = Flask(__name__)
app.secret_key = ';lkjnfdidiclsjek'

GENTIEMAN = {
    '1':{'name':'钢弹','count':0},
    '2':{'name':'铁锤','count':0},
    '3':{'name':'闫帅','count':0},
}

WEBSOCKET_DICT = {}

@app.before_request
def before_reuqest():
    if request.path == '/login':
        return None
    user_info = session.get('user_info')
    if user_info:
        return None
    return redirect('login')

@app.route('/login',methods=['GET','POST'])
def login():
    if request.method == 'GET':
        return render_template('login.html')
    else:
        uid = str(uuid.uuid4())
        session['user_info'] = {'id':uid,'name':request.form.get('user')}
        return redirect('/index')


@app.route('/index')
def index():
    return render_template('index.html',users=GENTIEMAN)

@app.route('/message')
def message():
    # 1. 判断是否为Websocket请求,http不包含wsgi.websocket
    ws = request.environ.get('wsgi.websocket')
    if not ws:
        return 'use websocket'
    # 此处连接成功
    current_user_id = session['user_info']['id']
    WEBSOCKET_DICT[current_user_id] = ws
    while True:
        # 2. 等待用户发送消息，并接受
        message = ws.receive()  # 投票对应的ID

        # 关闭 mesaage = None
        if not message:
            del WEBSOCKET_DICT[current_user_id]
            break

        # 3. 获取用户要投票的ID，并+1
        old = GENTIEMAN[message]['count']
        new = old + 1
        GENTIEMAN[message]['count'] = new

        data = {'user_id':message,'count':new,'type':'vote'}
        # 给所有客户端推送消息
        for conn in WEBSOCKET_DICT.values():
            conn.send(json.dumps(data))
    return '完毕'

@app.route('/notify')
def notify():
    data = {'data':'订单生成','type':'alert'}
    for conn in WEBSOCKET_DICT.values():
        conn.send(json.dumps(data))
    return '完毕'

if __name__ == '__main__':
    # 如果是http请求走app使用原有的wsgi处理，如果是websocket请求走WebSocketHandler处理
    http_server = WSGIServer(('127.0.0.1', 5000), app, handler_class=WebSocketHandler)
    http_server.serve_forever()

index.html

    
投票系统:参与投票的人
    

        {% for k,v in users.items() %}
            
"user_{{k}}" οndblclick="vote('{{k}}')">{{v.name}} {{v.count}} 

        {% endfor %}

    
    
    

 

login.html

"post">
    "text" name="user">
    "submit" value="提交">

 

转载于:https://www.cnblogs.com/sunlong88/p/9623707.html