MQTT

Hardware Requirements

SOC device like a Raspberry Pi
PSU
DHT22 Humidity and Temperature sensor
Network connection

Initial Software Requirements

Linux OS
Python3

Device Setup

sudo apt-get update; sudo apt-get upgrade
sudo apt-get install python3-dev python3-pip -y mosquitto-clients

sudo python3 -m pip install --upgrade pip setuptools wheel
sudo pip3 install --install-option="--force-pi" Adafruit_DHT

File Content

import Adafruit_DHT
from time import sleep
import paho.mqtt.client as mqtt


DHT_SENSOR = Adafruit_DHT.DHT22
DHT_PIN = 18
humidity, temperature = Adafruit_DHT.read_retry(DHT_SENSOR, DHT_PIN)
humidity = round(humidity, 2)
temperature = round(temperature, 2)

print(temperature)

broker_address="x.x.x.x"
client=mqtt.Client("xxx)
client.username_pw_set("xxxx", password="xxxx")
client.connect(broker_address)
client.publish("ID", "value")

client.publish("topic", temperature)
sleep(1)
client.publish("topic", humidity)
sleep(1)

Cron Setup

crontab * * * * * python3 /home/pi/projects/mqtt/app-DHT22.py