Question

一台笔记本电脑使用Ubuntu 18.04 LTS，另一台笔记本电脑使用Ubuntu 16.04 LTS。 Python 2。用pip安装了paho.mqtt。

我正在尝试通过MQTT将变量发送到服务器。我有自己的代码，以前可以运行，但现在不能运行。

现在，我尝试了以下示例代码 https://github.com/pradeesi/Paho-MQTT-with-Python

我没有收到任何错误消息，并且服务器端也没有收到消息。

这是代码： mqtt_subscribe.py

# Import package
import paho.mqtt.client as mqtt

# Define Variables
#MQTT_HOST = "iot.eclipse.org"
MQTT_HOST = "192.168.1.127"
MQTT_PORT = 1883
MQTT_KEEPALIVE_INTERVAL = 45
MQTT_TOPIC = "helloTopic"
MQTT_MSG = "hello MQTT"

# Define on connect event function
# We shall subscribe to our Topic in this function
def on_connect(mosq, obj, rc):
    mqttc.subscribe(MQTT_TOPIC, 0)

# Define on_message event function. 
# This function will be invoked every time,
# a new message arrives for the subscribed topic 
def on_message(mosq, obj, msg):
    print "Topic: " + str(msg.topic)
    print "QoS: " + str(msg.qos)
    print "Payload: " + str(msg.payload)

def on_subscribe(mosq, obj, mid, granted_qos):
    print("Subscribed to Topic: " + 
    MQTT_MSG + " with QoS: " + str(granted_qos))

# Initiate MQTT Client
mqttc = mqtt.Client()

# Assign event callbacks
mqttc.on_message = on_message
mqttc.on_connect = on_connect
mqttc.on_subscribe = on_subscribe

# Connect with MQTT Broker
mqttc.connect(MQTT_HOST, MQTT_PORT, MQTT_KEEPALIVE_INTERVAL)

# Continue monitoring the incoming messages for subscribed topic
mqttc.loop_forever()

和mqtt_publish.py

# Import package
import paho.mqtt.client as mqtt

# Define Variables
#MQTT_HOST = "iot.eclipse.org"
MQTT_HOST = "192.168.1.127"
MQTT_PORT = 1883
MQTT_KEEPALIVE_INTERVAL = 45
MQTT_TOPIC = "helloTopic"
MQTT_MSG = "hello MQTT"


# Define on_publish event function
def on_publish(client, userdata, mid):
    print "Message Published..."

# Initiate MQTT Client
mqttc = mqtt.Client()

# Register publish callback function
mqttc.on_publish = on_publish

# Connect with MQTT Broker
mqttc.connect(MQTT_HOST, MQTT_PORT, MQTT_KEEPALIVE_INTERVAL)        

# Publish message to MQTT Broker    
mqttc.publish(MQTT_TOPIC,MQTT_MSG)

# Disconnect from MQTT_Broker
mqttc.disconnect()

我认为笔记本电脑的某些网络设置有问题。谁能指出我如何调试该问题？这有什么问题吗？

在通过broker.mqttdashboard.com和本地（192.168.x.x）连接时尝试使用端口，而未提及端口。

MQTT服务器即使在同一台PC上也没有响应

0 个答案: