def _are_valid_credentials(self, username, password):
"""Checks whether credentials are valid"""
def _on_connect(client, userdata, flags, rc):
"""A callback that matches the MQTT client signature, that triggers when connection was established"""
userdata.set_return_code(rc)
client.disconnect()
client.loop_stop()
client.should_stop = True
con_result = ConnectionResult()
client = Client(userdata=con_result)
client.username_pw_set(username, password)
client.on_connect = _on_connect
start_time = time.time()
client.should_stop = False
client.connect_async(self.host, self.port)
client.loop_start()
while not client.should_stop and time.time(
) - start_time < self.timeout:
time.sleep(0.001)
return con_result.did_succeed
