mqtt server python_使用Mosquitto / Paho for Python无法接收超过20条MQTT消息

我正在使用Mosquitto(现在的Paho)

python MQTT客户端连接到HiveMQ代理.代码是非常基本的,取自他们的文档 –

https://pypi.python.org/pypi/paho-mqtt

#SUBSCRIBER

import paho.mqtt.client as mqtt

# The callback for when the client receives a CONNACK response from the server.

def on_connect(client, userdata, rc):

client.subscribe("GB/node0/", 2)

# The callback for when a PUBLISH message is received from the server.

def on_message(client, userdata, msg):

print "Topic: ", msg.topic+'\nMessage: '+str(msg.payload)

client = mqtt.Client()

client.on_connect = on_connect

client.on_message = on_message

client.connect("192.168.15.4", 1883, 60)

# Blocking call that processes network traffic, dispatches callbacks and

# handles reconnecting.

client.loop_forever()

正如您在client.subscribe()中注意到的那样,QoS是2.这是对官方文档代码的唯一修改.

发布客户的代码是 –

#PUBLISHER

import paho.mqtt.client as mqtt

mqttc = mqtt.Client("python_pub")

mqttc.connect("192.168.15.4", 1883, 60)

mqttc.publish("GB/node0/", "Hello, World baby!",2)

此处,QoS也是2.

QoS的这种修改导致订户仅接收20条消息.在进一步探测之后,我意识到问题可能是由于max_inflight_messages_set(),这是一个选项功能,它设置QoS> 0的最大消息数,这些消息可以一次通过其网络流.默认值为20.

但是,将其更改为任何其他值不起作用.此外,为什么客户认为这些消息在收到后仍然存在？我该如何解决这个问题？如何确保客户理解这些消息不是“飞行”并已交付？