python paho-MQTT

pip install paho-mqtt

paho-mqtt 是一个MQTT python client 库，支持mqtt 3.1/ 3.1.1协议。
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The MQTT protocol is a machine-to-machine (M2M)/”Internet of Things” connectivity protocol. Designed as an extremely lightweight publish/subscribe messaging transport, it is useful for connections with remote locations where a small code footprint is required and/or network bandwidth is at a premium.
Mosquitto是一个开源(BSD许可证)的消息代理，实现MQTT(消息队列遥测传输)协议版本3.1。

MQTT（MQ Telemetry Transport），消息队列遥测传输协议，轻量级的发布/订阅协议，适用于一些条件比较苛刻的环境，进行低带宽、不可靠或间歇性的通信。值得一提的是mqtt提供三种不同质量的消息服务：
“至多一次”，消息发布完全依赖底层 TCP/IP 网络。会发生消息丢失或重复。这一级别可用于如下情况，环境传感器数据，丢失一次读记录无所谓，因为不久后还会有第二次发送。
“至少一次”，确保消息到达，但消息重复可能会发生。
“只有一次”，确保消息到达一次。这一级别可用于如下情况，在计费系统中，消息重复或丢失会导致不正确的结果。

Mosquitto是一个开源(BSD许可证)的消息代理，实现MQTT(消息队列遥测传输)协议版本3.1。可以更加方便的使用

简单测试消息发布

简单测试消息订阅

使用python的paho-mqtt模块操作

import paho.mqtt.client as mqtt
import time

HOST = "127.0.0.1"
PORT = 61613

def client_loop():
    client_id = time.strftime('%Y%m%d%H%M%S',time.localtime(time.time()))
    client = mqtt.Client(client_id)    # ClientId不能重复，所以使用当前时间
    client.username_pw_set("admin", "123456")  # 必须设置，否则会返回「Connected with result code 4」
    client.on_connect = on_connect
    client.on_message = on_message
    client.connect(HOST, PORT, 60)
    client.loop_forever()

def on_connect(client, userdata, flags, rc):
    print("Connected with result code "+str(rc))
    client.subscribe("test")

def on_message(client, userdata, msg):
    print(msg.topic+" "+msg.payload.decode("utf-8"))
    # 消息处理

if __name__ == '__main__':
    client_loop()

# import paho.mqtt.client as mqtt
import paho.mqtt.publish as publish
import time

HOST = "127.0.0.1"
PORT = 61613
def on_connect(client, userdata, flags, rc):
    print("Connected with result code "+str(rc))
    client.subscribe("test")

def on_message(client, userdata, msg):
    print(msg.topic+" "+msg.payload.decode("utf-8"))

if __name__ == '__main__':
    client_id = time.strftime('%Y%m%d%H%M%S',time.localtime(time.time()))
    # client = mqtt.Client(client_id)    # ClientId不能重复，所以使用当前时间
    # client.username_pw_set("admin", "123456")  # 必须设置，否则会返回「Connected with result code 4」
    # client.on_connect = on_connect
    # client.on_message = on_message
    # client.connect(HOST, PORT, 60)
    # client.publish("test", "你好 MQTT", qos=0, retain=False)  # 发布消息

    publish.single("test", "你好 MQTT", qos = 1,hostname=HOST,port=PORT, client_id=client_id,auth = {'username':"admin", 'password':"123456"}
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原文：https://blog.youkuaiyun.com/csdnhuaong/article/details/79595123