用emq实现简单聊天室功能(含离线缓存数据)

EMQ官方地址:http://emqtt.com/ 
EMQ中文文档:http://emqtt.com/docs/v2/guide.html

在ubuntu上部署emq服务器，

#!/usr/bin/python3
# -*- coding: utf-8 -*-
# @Time    : 2018/11/21 10:58
# @Author  : Tom
# @File    : chat_a.py
# @Software: PyCharm

import paho.mqtt.client as mqtt
import json


def on_connect(client,userdata,flags,rc):
    print('connected with result code',str(rc))

    client.subscribe("chat")
    client.publish('chat',json.dumps('hello,everyone.....'))

def on_message(client,userdata,msg):
    info = json.loads(msg.payload.decode())
    say_user = info.get("user")
    if say_user != client.user:
        print(info.get('user')+": "+info.get('say')+'\n')

if __name__ == '__main__':
    HOST = '127.0.0.1'
    PORT = 1883

    client = mqtt.Client(client_id='2008001',clean_session=False)
    # client = mqtt.Client(client_id='2008002',clean_session=False)
    # client = mqtt.Client(client_id='2008003',clean_session=False)
    print('生成的client',client)
    client.on_connect = on_connect
    client.on_message = on_message

    client.connect(HOST,PORT)

    user = input('请输入名字:')
    client.user = user
    client.loop_start()

    while True:
        say_str = input('')
        if say_str:
            info = {'user':user,'say':say_str}
            client.publish('chat',json.dumps(info))