raspberrypi-temp-sensor/mqtt_publish_temp.py

import time
from datetime import datetime
import subprocess
import sys

# Import Adafruit_DHT
import Adafruit_DHT

# Import MQTT client.
import paho.mqtt.publish as publish
import paho.mqtt.client as paho

# MQTT credentials
#mqtt_username  = 'homeassistant' # MQTT client username
#mqtt_password = '3355' # MQTT client password
client_id = sys.argv[1] # unique client_id
mqtt_broker = "raspberrypi" # broker address, usually your HASS IP address

# DHT config
DHT_PIN = 4                     # GPIO nr
DHT_SENSOR = Adafruit_DHT.DHT22

# connection event
def on_connect(client, data, flags, rc):
    print('Connected: ' + str(rc))

# create the MQTT client
client = paho.Client(protocol=paho.MQTTv31)  # * set a random string (max 23 chars)

# Command topic
temperature_topic  = 'weathersensors/' + client_id + '/temperature'
humidity_topic = 'weathersensors/' + client_id + '/humidity'
time_topic = 'weathersensors/' + client_id + '/time'

#client connection
#client.username_pw_set(mqtt_username, mqtt_password)  # MQTT server credentials
client.connect(mqtt_broker)  # MQTT server address

client.loop_start()

while True:
        # DATETIME
        now = datetime.now()
        #print("now =", now)
        #Output format: DD/MM/YYYY H:M:S
        dt_string = now.strftime("%d-%m-%Y %H:%M:%S")

        print(dt_string)
        # Get Temperature from DHT
        _, temperature = Adafruit_DHT.read_retry(DHT_SENSOR, DHT_PIN)

        print("temperature before cut: " + str(temperature))
        # cut temperature to xx.xx if more then tow digits after "."
        t_split = str(temperature).split(".")
        if len(t_split[1]) > 2:
            t_cut = len(t_split[1]) - 2
            t_split[1] = t_split[1][:-t_cut]
        temperature = t_split[0] + "." + t_split[1]

        print("temperature after cut: " + temperature)
        # Get Humidity from DHT
        humidity, _ = Adafruit_DHT.read_retry(DHT_SENSOR, DHT_PIN)

        print("humidity before cut: " + str(humidity))
        # cut humidity to xx.xx if more then tow digits after "."
        h_split = str(humidity).split(".")
        if len(h_split[1]) > 2:
            h_cut = len(h_split[1]) - 2
            h_split[1] = h_split[1][:-h_cut]
        humidity = h_split[0] + "." + h_split[1]

        print("humidity after cut: " + humidity)
        # Publish our data
        client.publish(temperature_topic, temperature)
        client.publish(humidity_topic, humidity)
        client.publish(time_topic, dt_string)

        time.sleep(30)