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'
availability_topic = 'weathersensors/' + client_id + '/availability'

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

# 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 round: " +str(temperature))

temperature = round(float(temperature),2)

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

humidity = round(float(humidity),2)

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