Python script to forward a thermal zone temperature to Domoticz, with e-mail notification when the temperature is over a threshold.

cputemp.py

#!/usr/bin/python3
# coding: utf-8

# Python script to read the CPU temperature and send the results to
# a Domoticz server. Meant to be executed by cron at regular intervals.
#
# 
# Requires: Python 3
#
# Version: 2.1
# Date:    2024-08-20
# License:  0BSD@https://spdx.org/licenses/0BSD.html

# Needed module here because LOG_XXX constants are used in parameters
from syslog import *

# User defined parameters -------------------------------------------------------
alertTemp       = 60        # Hot cpu core temperature threshold
cpu_zone        = "/sys/class/thermal/thermal_zone1/temp"
cpu_temp_idx    = 211       # Domoticz device index for cpu temperature sensor on vault.local
domoticzJson    = "http://192.168.1.22:8080/json.htm?type=command&param=udevice&idx={}&nvalue=0&svalue={}"
domoticzTimeout = 15        # HTTP request timeout in seconds
alertTitle      = 'NAS Temperature Alert'
alertMsg        = "The temperature of the NAS CPU, {}°C, is above the alert threshold {}°C"
verbose         = 0         # 0 quiet, 1 to echo log messages with priority
consoleloglevel = LOG_ERR   # log level for messages printed to the console
sysloglevel     = LOG_ERR   # log level for messages sent to syslog
logAlertLevel   = LOG_ALERT # priority level for e-mail temperature alerts
# -------------------------------------------------------------------------------

# Needed modules in addition to syslog
import sys
import os
from pymail import send_email
from urllib.request import urlopen  # with python 3.x, use "from urllib2 import urlopen"  with python 2.7
if verbose > 0:
  from datetime import datetime

# Routine to send messages to syslog and echo it to the console
def log(level, msg):
  syslog(level, msg)
  if (verbose) and (level <= consoleloglevel):
    print(datetime.now().strftime('%Y-%m-%d %H:%M:%S ') + msg)

# Setup syslog
openlog(ident='NAS')
setlogmask(LOG_UPTO(sysloglevel))

# HTTP Get request
def httpRequest(url):
  try:
    log(LOG_DEBUG, 'CPU: Domoticz GET request: {}'.format(url))
    # use context magager which takes care of closing hf
    with urlopen(url, timeout=domoticzTimeout) as hf:
      # get Domoticz' response and broadcast it
      response = hf.read().decode('utf-8')
      if ('"ERR"') in response:
        llevel = LOG_ERR
      else:
        llevel = LOG_DEBUG
      log(llevel, 'Domoticz response: {}'.format(response))

  except Exception as e:
    log(LOG_ERR, 'Exception: {}'.format(e))

# Read and report cpu temperature
with open(cpu_zone) as f:
    cpuTemp = "{0:0.1f}".format(int(f.read())/1000.0)
log(LOG_DEBUG, 'CPU: temp = {}°C'.format(cpuTemp))
httpRequest(domoticzJson.format(cpu_temp_idx, cpuTemp))

# Raise alert if needed
if float(cpuTemp) > alertTemp:
  message = alertMsg.format(cpuTemp, alertTemp)
  log(LOG_DEBUG, "Alert, title: '{}', message: '{}'".format(alertTitle, message))
  log(logAlertLevel, message)
  log(LOG_DEBUG, 'Sending email notification')
  send_email(alertTitle, 'temperature.alert@gmail.com', message)

get_thermal_zones.sh

#!/usr/bin/bash

# Bash script that reads the thermal zone temperatures from the Linux
# /sys virtual file system.
#
# Ref: How to display CPU temperature in bash prompt?
#   @: https://unix.stackexchange.com/questions/411115/how-to-display-cpu-temperature-in-bash-prompt
#
# Version 0.2
# (c) Copyright 2024 Michel Deslierres, No rights reseved
# This script is in the public domain. In those jurisdictions where this may be a problem, the 
# BSD Zero Clause License (https://spdx.org/licenses/0BSD.html) applies. 

CEL=$'\xc2\xb0C' # UTF-8 codepoint for the degree symbol followed by C (celsius)

for zone in $(ls -d /sys/devices/virtual/thermal/thermal_zone*);
do
  temp=$(cat $zone/temp)
  typ=$(cat $zone/type)
  temp=`expr $temp / 1000`
  echo $zone: $temp$CEL $typ
done

pymail.py

#Import smtplib for the actual sending function
import smtplib, ssl
# Import the email modules we'll need
from email.mime.text import MIMEText

SRC = '***me@**host_url****'
SMPT = '***mail@**host_url****'
PORT = 465
PWD = '****************'

def send_email(subject, dest, message):
  print('send_email({}, {}, {})'.format(subject, dest, message))

  # Create the message
  msg = MIMEText(message)
  msg['Subject'] = subject
  msg['From'] = SRC
  msg['To'] = dest

  context = ssl.create_default_context()
  with smtplib.SMTP_SSL(SMPT, PORT, context=context) as server:
    server.login(SRC, PWD)
    server.sendmail(SRC, dest, msg.as_string())

  print('msg:', msg['Subject'], msg['From'], msg['To'])

  # ref: https://realpython.com/python-send-email/ #