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ConnectionError is not defined - MQTT Paho on Python

I'm using the code below to connect to a broker via WebSocket and SSL. The broker is password protected. My code -

import paho.mqtt.client as mqtt
import ssl
import time

def on_connect(client, userdata, flags, rc):
    print("connected with result code "+str(rc))

def on_publish(client, userdata, mid):
    print("mid: "+str(mid))

client = mqtt.Client('device', transport="websockets")
client.on_connect = on_connect
client.on_publish = on_publish

client.username_pw_set("login", "pass")
client.ws_set_options(path="/logger")
client.tls_set(ca_certs=None, certfile=None, keyfile=None, cert_reqs=ssl.CERT_REQUIRED,
    tls_version=ssl.PROTOCOL_TLS, ciphers=None)

connection = False


print("Trying to connect ...")
client.connect(host="mqtt.broker.io", port=443)
connection = True

for _ in range(5):
    time.sleep(1)
    client.publish("some/topic", "HELLO", qos=2)
    client.loop(1)

client.disconnect()

The error I'm getting -

Trying to connect ... connected with result code 0 Traceback (most recent call last): File "/home/souvik/GitLab/Embedded/demo_mqtt_auth.py", line 30, in client.loop(1) File "/home/souvik/.local/lib/python2.7/site-packages/paho/mqtt/client.py", line 1120, in loop return self._loop(timeout) File "/home/souvik/.local/lib/python2.7/site-packages/paho/mqtt/client.py", line 1164, in _loop rc = self.loop_read() File "/home/souvik/.local/lib/python2.7/site-packages/paho/mqtt/client.py", line 1556, in loop_read rc = self._packet_read() File "/home/souvik/.local/lib/python2.7/site-packages/paho/mqtt/client.py", line 2373, in _packet_read except ConnectionError as err: NameError: global name 'ConnectionError' is not defined

sleepiz_one on  hw-1929-diagnostics [$!] on  (eu-west-1) took 6s ❯ /bin/python /home/souvik/GitLab/Embedded/demo_mqtt_auth.py Trying to connect ... connected with result code 0 Traceback (most recent call last): File "/home/souvik/GitLab/Embedded/demo_mqtt_auth.py", line 30, in client.loop(1) File "/home/souvik/.local/lib/python2.7/site-packages/paho/mqtt/client.py", line 1120, in loop return self._loop(timeout) File "/home/souvik/.local/lib/python2.7/site-packages/paho/mqtt/client.py", line 1164, in _loop rc = self.loop_read() File "/home/souvik/.local/lib/python2.7/site-packages/paho/mqtt/client.py", line 1556, in loop_read rc = self._packet_read() File "/home/souvik/.local/lib/python2.7/site-packages/paho/mqtt/client.py", line 2373, in _packet_read except ConnectionError as err: NameError: global name 'ConnectionError' is not defined

Not too sure where I'm getting the exception from. Even though I get the exception, I do see data on the broker, so I'm not sure what's

EDIT: I'm on paho-mqtt 1.6.1

Solution

  • ConnectionError was added in Python 3.3.

    You're running on Python 2.7, which has been end-of-life for 3 years.

    You could have some luck downgrading your paho-mqtt to a version before 1.6.0, as that's the first version that has this commit referring to ConnectionError:

    pip install paho-mqtt==1.5.1

    or alternatively up to 1.6.1 which claims to "fix Python 2.7 compatibility":

    pip install paho-mqtt==1.6.1

    Really, though, you should stop using Python 2.7, since it has not been supported for a long while now.