There are three files: broker.py; sub.py; pub.py;
broker.py:
import logging
import asyncio
from hbmqtt.broker import Broker
logger = logging.getLogger(__name__)
config = {
'listeners': {
'default':{
'type': 'tcp',
'bind': 'localhost:9999'
}
},
'sys_interval': 10,
'topic-check':{
'enabled': False
}
}
broker = Broker(config)
@asyncio.coroutine
def startBroker():
yield from broker.start()
if __name__ == '__main__':
formatter = "[%(asctime)s] :: %(levelname)s :: %(name)s :: %(message)s"
logging.basicConfig(level=logging.INFO, format=formatter)
asyncio.get_event_loop().run_until_complete(startBroker())
asyncio.get_event_loop().run_forever()
sub.py:
import paho.mqtt.client as mqtt
client = mqtt.Client()
client.connect('localhost', 9999)
def on_connect(client, userdata, flags, rc):
print("Connected to a broker!")
client.subscribe("LINTANGtopic/test")
def on_message(client, userdata, message):
print(message.payload.decode())
while True:
client.on_connect = on_connect
client.on_message = on_message
client.loop_forever
pub.py:
import paho.mqtt.client as mqtt
client = mqtt.Client()
client.connect('localhost', 9999)
while True:
client.publish("LINTANGtopic/test", input('Message: '))
So I first opened three terminals: In the first terminal, I entered "py broker.py" and it works well; In the second terminal, I entered "py sub.py" and it does not work and show nothing in the second terminal which should show "Connected to a broker" although it made the first terminal to show that :
[2020-07-29 14:01:41,925] :: INFO :: hbmqtt.broker :: Listener 'default': 1 connections acquired
[2020-07-29 14:01:41,926] :: INFO :: hbmqtt.broker :: Connection from ::1:50450 on listener 'default'
[2020-07-29 14:01:41,937] :: INFO :: transitions.core :: Exited state new
[2020-07-29 14:01:41,937] :: INFO :: transitions.core :: Entered state connected
In the third terminal, I entered "py pub.py" and it showed like this:
D:\MQTT>py pub.py
Message:
I need to make the subscriber to be connected to a broker and I would like to know why this happened?
sub.py won't work as you have it.
First client.loop_forever
is a function so needs to be called with ()
.
Second, the while True:
loop is redundant and you shouldn't be setting the callback repeatedly.
Try the following:
import paho.mqtt.client as mqtt
def on_connect(client, userdata, flags, rc):
print("Connected to a broker!")
client.subscribe("LINTANGtopic/test")
def on_message(client, userdata, message):
print(message.payload.decode())
client = mqtt.Client()
client.on_connect = on_connect
client.on_message = on_message
client.connect('localhost', 9999)
client.loop_forever()