#!/usr/bin/python
################################################################################
## Kontrollkit
## NAME: kt-url-monitor.py
## DATE: 2010-02-24
## AUTHOR: Matt Reid
## WEBSITE: http://kontrollsoft.com
## EMAIL: support@kontrollsoft.com
## LICENSE: BSD http://www.opensource.org/licenses/bsd-license.php
################################################################################
## Copyright 2010-present Matt Reid
## All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in the
#    documentation and/or other materials provided with the distribution.
# 3. The name of the author may not be used to endorse or promote products
#    derived from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
##################################################################################
## WHAT THIS SCRIPT DOES #########################################################
## Purpose: Checks URL for valid page and emails if failed. 
##################################################################################
## EDIT THE FOLLOWING AS NEEDED
email = "email@email.com" ##Email address to send alert to
host = "hostname.com" ##Hostname base URL without http://
port = "80" ##Port - 80 for http, 443 for https
url = "/index.html" ##Page to look for on host
SENDMAIL = "/usr/sbin/sendmail" ##Binary location for sendmail
logfile = "/var/log/kt-url-monitor.log" ##Logfile to write actions to
## END OF EDITABLE OPTIONS
##################################################################################
import sys
import os
import os.path
import datetime
from httplib import HTTP

def wfile(detail):
    fstate = os.path.exists(logfile)
    if(fstate == 0):
        print "Logfile does not exist. Attempting to create..."
        try:
            file = open(logfile,"a+")
            file.writelines(detail)
            file.close()
            
        except IOError:
            print "Cannot open logfile for writing. Exiting."
            sys.exit(1)

    else:
        print "Logfile exists, writing...\n"
        file = open(logfile,"a+")
        file.writelines(detail)
        file.close()

def get(host,port,url):
    concaturl = host+url
    print "Checking Host:",concaturl
    h = HTTP(host, port)
    h.putrequest('GET', url)
    h.putheader('Host', host)
    h.putheader('User-agent', 'python-httplib')
    h.endheaders()
    
    (returncode, returnmsg, headers) = h.getreply()
    if returncode != 200:
        print returncode,returnmsg
        return returncode

    else:
        f = h.getfile()
        #    return f.read() #returns content of page for further parsing
        print returncode, returnmsg
        return returncode

if __name__ == '__main__':
    now = datetime.datetime.now()
    date = now.strftime("%Y-%m-%d %H:%M:%S")
    dmsg = date+" - URL verification starting - "
    wfile(dmsg)
    concaturl = "http://"+host+url
    state = get(host,port,url)

    if(state != 200):
        msg = "Link (%s) is broken or unavailable. Return code: %s" % (concaturl,state)+"\n"
        wfile(msg)
        to = "To: "+email+"\n"
        print msg,"\n"
        p = os.popen("%s -t" % SENDMAIL, "w")
        p.write(to)
        p.write("Subject: Demo Server Status\n")
        p.write("\n") 
        p.write(msg)
        sts = p.close()
        if sts != 0:
            print "Sendmail exit status", sts
    else:
        msg = "Link (%s) is good. Return code: %s" % (concaturl,state)+"\n"
        wfile(msg)
        print msg+"\n"