zoukankan      html  css  js  c++  java
  • python mqtt 客户端实现

    安装paho-mqtt

    pip install paho-mqtt -i http://pypi.douban.com/simple --trusted-host pypi.douban.com

    python消息收发实现

    import paho.mqtt.client as mqtt
    from multiprocessing import Process
    import camera_person_num
    
    MQTTHOST = "172.19.4.4"
    MQTTPORT = 1883
    mqttClient = mqtt.Client()
     
     
    # 连接MQTT服务器
    def on_mqtt_connect():
        mqttClient.connect(MQTTHOST, MQTTPORT, 60)
        mqttClient.loop_start()
    
      
    # 消息处理函数
    def on_message_come(lient, userdata, msg):
        print(msg.topic + ":" + str(msg.payload.decode("utf-8")))
        # 消息处理开启多进程
        p = Process(target=talk, args=("/camera/person/num/result", msg.payload.decode("utf-8")))
        p.start()
    
     
    # subscribe 消息订阅
    def on_subscribe():
        mqttClient.subscribe("test", 1)  # 主题为"test"
        mqttClient.on_message = on_message_come  # 消息到来处理函数
    
    
    # publish 消息发布
    def on_publish(topic, msg, qos):
        mqttClient.publish(topic, msg, qos);
    
    
    # 多进程中发布消息需要重新初始化mqttClient
    def talk(topic, msg):
        cameraPsersonNum = camera_person_num.CameraPsersonNum(msg)
        t_max, t_mean = cameraPsersonNum.personNum()
        mqttClient = mqtt.Client()
        mqttClient.connect(MQTTHOST, MQTTPORT, 60)
        mqttClient.loop_start()
        mqttClient.publish(topic, '{"max":' + str(t_max) + ',"mean:"' + str(t_mean) + '}', 1)
    
     
    def main():
        on_mqtt_connect()
        on_subscribe()
        while True:
            pass
     
     
    if __name__ == '__main__':
        main()
    
  • 相关阅读:
    4个小时实现一个HTML5音乐播放器
    一款好看+极简到不行的HTML5音乐播放器-skPlayer
    操纵浏览器的历史记录
    基于jQuery查找dom的多种方式性能问题
    你真的了解console吗?
    关于overflow:hidden和bfc
    jQuery插件开发
    深入浅出jsonp
    jQuery.extend 函数详解
    [转] Hibernate一级缓存、二级缓存
  • 原文地址:https://www.cnblogs.com/gmhappy/p/9472371.html
Copyright © 2011-2022 走看看