Digi Connect IT 4 - Page 627

Applications Develop Python applications
Digi Connect IT® 4 User Guide
627
return
reply = {
"cmd": cmd,
"status": status
}
client.publish(PREFIX_RSP + path + "/" + cid, json.dumps(reply, separators=
(',',':')))
def on_connect(client, userdata, flags, rc):
print("Connected to MQTT server")
client.subscribe(PREFIX_CMD + "/system")
def on_message(client, userdata, msg):
""" Supporting only a single topic for now, no need for filters
Expects the following message format:
{
"cid": "<client-id>",
"cmd": "<command>",
"params": {
<optional_parameters>
}
}
Supported commands:
- "fw-update"
params:
- "uri": "<firmware_file_URL>"
- "reboot"
params:
"""
try:
m = json.loads(msg.payload)
cid = m["cid"]
cmd = m["cmd"]
try:
payload = m["params"]
except:
payload = None
except:
print("Invalid command format: {}".format(msg.payload))
if not cid:
# Return if client-ID not passed
return None
send_cmd_reply(client, msg.topic, cid, cmd, HTTPStatus.BAD_REQUEST)
try:
status = CMD_HANDLERS[cmd](payload)
except:
print("Invalid command: {}".format(cmd))
status = HTTPStatus.NOT_IMPLEMENTED
send_cmd_reply(client, msg.topic, cid, cmd, status)
def publish_dhcp_leases():
leases = []
try: