Poor Man's Guide for Monitoring a Website Using Python on Ubuntu and Restarting Apache when it is down. http://www.mos3abof.com/poor-man-website-python-monitor.html

restart_apache_fabfile.py

#!/usr/bin/python
# -*- coding: utf-8 -*-
 
# Import DateTime
from datetime import datetime, timedelta, date
 
# Import urllib
import urllib
 
# Importing utilities from Fabric
from fabric.api import env, sudo
 
# Import email stuff
import smtplib
from email.MIMEMultipart import MIMEMultipart
from email.MIMEBase import MIMEBase
from email.MIMEText import MIMEText
from email import Encoders
 
# For debugging purposes
import traceback
 
# Import Logging lib
import logging
 
# Setting up Logging 
current_date 			= date.today()
current_log_file_name 		= '/opt/fab_logs/' + current_date.isoformat() + '.log'
logging.basicConfig( format 	= '%(asctime)s [%(levelname)s] %(message)s', 
		    filename 	= current_log_file_name, 
		    level 	= logging.INFO)
 
# Defining the env.hosts
env.hosts 	= ['username@server-address']
env.passwords 	= {'username@server-address' : 'passoword' }
 
 
# The function that actually sends email
def mail(to, subject, text, gmail_user, gmail_pwd):
	'''
	Sends mail using gmail
	'''
	msg = MIMEMultipart()
 
	# Setting up message data
	msg['From'] 	= 'alterts@yoursite.com'
	msg['To'] 	= to
	msg['Subject']	= subject
 
	msg.attach(MIMEText(text))
 
	# Opening the connection with Gmail SMTP server
	mailServer = smtplib.SMTP("smtp.gmail.com", 587)
	mailServer.ehlo()
	mailServer.starttls()
	mailServer.ehlo()
	mailServer.login(gmail_user, gmail_pwd)
 
	# Actual sending of the email
	mailServer.sendmail(gmail_user, to, msg.as_string())
	
	# Closing the connection
	# Should be mailServer.quit(), but that crashes
	mailServer.close()
 
# Alerting the DevOps Team
def alert_dev_team(message = ''):
	'''
	This functions emails the DevOps Team that there is a downtime
	'''
	# Constructing the email message
	subject		= 'YOUR WEBSITE IS DOWN'
	email_body	= 'YOUR WEBSITE IS DOWN. \nTime now is {} \n{}'.format(date.today().isoformat(), message)
	gmail_user	= 'GMAIL-USERNAME'
	gmail_pwd	= 'PASSWORD'
	logging.debug("Constructed Email message")
	recepient 	= 'alerts@yoursite.com'

	# Sending the message
	mail(recepient, subject,  email_body, gmail_user, gmail_pwd)
	logging.debug("Finished sending all messages")
 
 
# Let the magic begin
def restart_apache():
	'''
	Checks if Apache2 server on YOUR WEBSITE is accessible through the web.
	If not it attemptes to restart it and alert the Dev Team.
 
	It should be added to cron to run every 5 minutes like this :
 
	*/5 * * * * /usr/bin/fab -f /opt/fabfile.py restart_apache
	'''
 
	try:
		logging.info("The script was invoked by the cron")
 
		# Open the site using urllib
		result = urllib.urlopen("http://www.yourwebsite.com").getcode()
 
		# if the alue of the respsonse is not 200 then raise an error
		if not result == 200:
			raise ValueError
		# Log the attempt and successful result
		logging.info("The result came back {}".format(result))
		logging.info("Everything seems fine! Over and out!")
 
	# if we don't get a response at all or the value is not 200 OK then start the mechanism
	except:
		# Something with the wsbite is not right, attempt to restart the Apache server
		logging.error("Houston, we have got a problem! Attempting an Apache restart")
		logging.debug(traceback.format_exc())
		
		# setup the message to email to DevOps team
		message = 'Restart attempt complete. Everything should be fine now'
 
		try:
			# restart apache using sudo
			sudo('apache2ctl restart')
 
		except:
			# If the restart attempt fails we should know!
			logging.error("WE FAILED! The script couldn't restart the Apache. Human intervention needed!")
			logging.error(traceback.format_exc())
			message = "WE FAILED! The script couldn't restart the Apache. Human intervention needed!"
 
		try:
			# Attempt to alert the DevOps team
			alert_dev_team(message)
			logging.info("Sending an email to alerts@yoursite.com")
		except:
			logging.error('Tried sending an email and failed!')
		logging.info("Restart attempt complete. Everything should be fine now")