Digi Connect IT 16, Руководство пользователя

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Applications Use the Paho MQTT python library
Digi Connect IT® 16/48 User Guide 479
3. At the shell prompt, use the python command with no parameters to enter an interactive
Python session:
# python
Python 3.6.12 (default, Jan 11 2021, 10:25:21)
[GCC 8.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>>
4. Import the serial module:
>>> import serial
>>>
5. You can now perform operations on the serial port. For example, to write a message to the
serial port:
>>> s = serial.Serial("/dev/serial/USB_port1", 115200)
>>> s.write(b"Hello from USB serial port")
26
>>>
6. Use Ctrl-D to exit the Python session. You can also exit the session using exit() or quit() .
Use the Paho MQTT python library
Your Connect IT 16/48 device includes support for the Paho MQTT python library. MQTT is a
lightweight messaging protocol used to communicate with various applications including cloud-based
applications such as Amazon Web Services and Microsoft Azure. The following is example code that
reads some data from updates the device firmware, then publishes information about DHCP clients
and system information to the MQTT server.
"""
MQTT client example:
- Reporting some device metrics from runt
- Reporting DHCP clients
- Firmware update feature (simple implementation, read TODO in cmd_fwupdate)
"""
import sys
import time
import paho.mqtt.client as mqtt
import json
from acl import runt, config
from http import HTTPStatus
import urllib.request
import tempfile
import os
from digidevice import cli
POLL_TIME = 60
def cmd_reboot(params):
print("Rebooting unit...")
try: