如何处理loop_stop（）Paho MQTT

Question

我尝试通过MQTT将小型模型车连接到经纪人。每当他们通过轨道的某个部分（此处== 20）时，他们就连接到代理，订阅并发送具有当前位置的消息。从经纪人收到消息后，他们应该与经纪人断开连接。到目前为止，这种方法效果很好，但是只有在他们第一次越过片段== 20时。一旦客户端（汽车）断开连接并使用loop_stop（）终止循环，如果他们再次越过该部分，就什么也不会发生。如果我不断开连接并停止循环，则一切正常-但我希望它们断开连接并停止循环。您知道这里有什么问题吗？

from overdrive import Overdrive
import time
import paho.mqtt.client as mqtt

自动班级：

def __init__(self, macaddr):
    self.car = Overdrive(macaddr)
    self.client = CarClient(macaddr)
    self.check = 0


def startEngine(self):


    self.car.changeSpeed(300, 1000)
    self.car.setLocationChangeCallback(self.locationChangeCallback) # Set location change callback to function above


def locationChangeCallback(self, addr, location, piece, speed, clockwise):

    if piece == 20 :

        self.client.run(piece)

CarClient类：

def __init__(self, id):
    self.client = mqtt.Client(id)
    self.id = id


def on_connect(self, mqttc, obj, flags, rc):
    print("connected" + str(rc))

def on_message(self, mqttc, obj, msg):
    print("received message" + " " + str(msg.payload))
    self.client.disconnect() #if i remove this and the following line, everything works fine
    self.client.loop_stop() #but i have to disconnect and stop the loop after they received a message


def on_publish(self, mqttc, obj, mid):
    print("Data published " + str(mid))

def on_subscribe(self, mqttc, obj, mid, granted_qos):
    print("Subscribed: " + str(mid) + " " + str(granted_qos))

def on_log(self, mqttc, obj, level, string):
    print(string)

def run(self, position):

        self.position = position

        self.client.on_message = self.on_message
        self.client.connect("localhost", 1883, 60)  # connect to broker
        time.sleep(0.1)
        self.client.subscribe("test_channel")  # subscribe topic
        self.client.loop_start()

        self.client.publish("test_channel1", "ID:" + str(self.id) + " Position: " + str(position))

Main（）

def main():

  bmw = Auto("D8:4E:11:7C:25:BD")
  bmw.startEngine()


if __name__ == '__main__' :
    main()

Answer 1

我终于找到了问题。停止循环的函数不称为loop_stop（），其称为loop.stop（）。

因此代码段必须更改为以下内容：

def on_message(self, mqttc, obj, msg):
    print("received message" + " " + str(msg.payload))
    self.client.disconnect()
    self.client.loop.stop() 

仍然感谢