How to temporary disconnect from MQTT topics

Question

I implemented connection to broker like:
app.py

import paho.mqtt.client as mqtt
client = mqtt.Client(client_id='my_client', clean_session=False)
my_client = MyClient(client)
try:
    my_client.start()
    while True:
        try:
            client.loop()
        except Exception as e:
            my_client.start()
except Exception as e:
    client.loop_stop()
    exit(1)

MyClient.py

class MyClient:
    def __init__(self, mqtt=None):
         self.mqtt = mqtt

    def start(self):
        self.mqtt.subscribe('some/topic')

I have part of code where I want to pause topics listening:

self.mqtt.unsubscribe('some/topic')

And later I want to subscribe back to it I want to call start() again like: self.start()

But it never subscribe again. Any idea why?

Answer 1

Calling start() after the exception is thrown won't work as the client is most likely not connected at that point.

You should move your subscriptions to the on_connect callback then it will always re-subscribe after the client has (re)connected

As for your original question, probably better to just set a boolean flag and use it to gate processing the message rather than unsubscribing/subscribing when you want to ignore messages.