university-final-iot-backend/app/mqtt/mqtt_client.py

68 lines
2.2 KiB
Python

import sys
import json
from flask_mqtt import Mqtt
import app.devices as devices
class MqttClient:
__initialized = False
mqtt = Mqtt()
# Mqtt setup
@staticmethod
def setup(app):
if not MqttClient.__initialized:
MqttClient.mqtt.init_app(app)
MqttClient.mqtt.client.on_message = MqttClient.handle_mqtt_message
MqttClient.mqtt.client.on_subscribe = MqttClient.handle_subscribe
MqttClient.__initialized = True
@MqttClient.mqtt.on_connect()
def handle_connect(client, userdata, flags, rc):
print('MQTT client connected')
MqttClient.mqtt.subscribe('device/+')
@MqttClient.mqtt.on_disconnect()
def handle_disconnect():
print('MQTT client disconnected')
print('MQTT client initialized')
@staticmethod
def tear_down():
if MqttClient.__initialized:
MqttClient.mqtt.unsubscribe_all()
if (hasattr(MqttClient.mqtt, 'client') and
MqttClient.mqtt.client is not None):
MqttClient.mqtt.client.disconnect()
print('MQTT client destroyed')
@staticmethod
def handle_subscribe(client, userdata, mid, granted_qos):
print('MQTT client subscribed')
@staticmethod
def handle_mqtt_message(client, userdata, message):
print("Received message!")
print("Topic: " + message.topic)
print("Payload: " + message.payload.decode())
try:
# If type is JSON
devices.create_recording(
MqttClient.get_device_id(message.topic),
json.loads(message.payload.decode()))
except ValueError:
print("ERROR!")
error_type, error_instance, traceback = sys.exc_info()
print("Type: " + str(error_type))
print("Instance: " + str(error_instance))
return
@staticmethod
def get_device_id(topic) -> int:
device_token, device_id = topic.split("/")
if device_token == "device":
return int(device_id)
else:
raise ValueError("Topic is in invalid format")