Question

我正在做一个使用Django和MQTT的项目。有一种情况，当我的Django Web服务器由于某种原因断开连接后重新连接到代理时，我想重新订阅与数据库中的模型有关的所有主题。我的模型室如下：

class Room(models.Model):
building    = models.ForeignKey(Building, on_delete= models.CASCADE)
number      = models.PositiveIntegerField()
available   = models.BooleanField(default=True)
power       = models.BooleanField(default=False)

class Meta:
    ordering = ['building', 'number']
    unique_together = ['building', 'number']

def __str__(self):
    return f"{self.building.bid}/{self.number}"

def get_mqtt_topic(self):
    return f"{self.building.bid}/{self.number}"

方法get_mqtt_topic（）将返回与房间关联的MQTT主题。 MQTT客户端代码mqtt / client.py：

import paho.mqtt.client as mqtt
from .tasks import *
from .models import Room
def on_connect(client, userdata, flags, rc):
   print("Connecting to CloudMQTT broker: "+ mqtt.connack_string(rc))
   room_mqtt = [(room.get_mqtt_topic(), 1) for room in Room.objects.all()]
   client.subscribe(room_mqtt)

client = mqtt.Client()
client.on_connect = on_connect
client.on_message = on_message

因为我将下面的代码放在 init .py中，以便在与django应用程序不同的线程中运行mqtt客户端。

from mqtt.client import client

client.loop_start()

所以我得到了这个错误：django.core.exceptions.AppRegistryNotReady：应用尚未加载。

Answer 1

我有同样的错误，我的临时解决方案是在on_connect方法中导入。

import paho.mqtt.client as mqtt
from .tasks import *
def on_connect(client, userdata, flags, rc):
    from .models import Room
    print("Connecting to CloudMQTT broker: "+ mqtt.connack_string(rc))
    room_mqtt = [(room.get_mqtt_topic(), 1) for room in Room.objects.all()]
    client.subscribe(room_mqtt)

client = mqtt.Client()
client.on_connect = on_connect

将Paho MQTT与Django集成

1 个答案: