#!/usr/bin/env python
#
# Program: check_xml
# Version: 1.0
# Date   : Nov 14, 2014
# Author : Phillipe Smith <phillipelnx@gmail.com>
# License: GPL (summary below and full text at http://www.fsf.org/licenses/gpl.txt)
#   This program is free software; you can redistribute it and/or modify
#   it under the terms of the GNU General Public License as published by
#   the Free Software Foundation; either version 2 of the License, or
#   (at your option) any later version.
#
#   This program is distributed in the hope that it will be useful,
#   but WITHOUT ANY WARRANTY; without even the implied warranty of
#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#   GNU General Public License for more details.
#
#   You should have received a copy of the GNU General Public License
#   along with this program; if not, write to the Free Software
#   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
#
#
# Description: 
#   Nagios plugin to make services based on XML file or URL.
#   The plugin generates the service based on Xpath based search
#
# Command line usage example:
#   ./check_xml -u 'http://adobe_flash_media_server:1111/admin/getServerStats?auser=admin&apswd=admin' -n 'data/io/connected,total_connects,total_disconnects' -l 'connected:80:100'
#   ./check_xml -f teste-file.xml -n './status,timestamp:./Users/connected:./Users/user/name,email' -l 'connected:80:100'
#
# Nagios configuration example:
#   define command {
#       command_name    check_xml
#       command_line    $USER1$/check_xml -u "$ARG1$" -n "$ARG2$" -l "$ARG3$" -p
#   }
#
#   define service {
#       use                    generic_service 
#       host_name              HOST_1
#       service_description    Adobe Flash Media Server Connections
#       check_command          check_xml!data/io/connected,total_connects,total_disconnects!connected:80:100
#   }
#   
# 

# Importing necessary python modules
import sys
from urllib2 import urlopen, HTTPError, URLError
from optparse import OptionParser

# Plugin options definitions
parser = OptionParser()
parser.add_option('-u', '--url', dest='url', default=False, help='XML Document URL')
parser.add_option('-f', '--file', dest='file', default=False, help='XML Document File')
parser.add_option('-l', '--levels', dest='levels', default='', help='Thresholds based on the node name\nThe format must be like: "node_name:warn:crit". Ex.: "users_connected:80:100,total_users:100:150"')
parser.add_option('-n', '--childnode', dest='childNode', default=False, help='Retrive childNode(s) value(s) from given XPath format,\n plus conma separated child nodes \nEx.: /Users/user/name,email,address')
parser.add_option('-p', '--perfdata', dest='perfdata', action='store_true', help='Generate perfdata')
options, args = parser.parse_args()

# Variables definitions
result   = []
info     = '' 
textinfo  = ''
url       = options.url
file      = options.file
childNode = options.childNode 
levels    = options.levels.strip().split(',')
perf      = options.perfdata
perfdata  = []

# Try import python xml module
try:
    import xml.etree.cElementTree as elt
except ImportError:
    import xml.etree.ElementTree as elt

# Try retrieve XML informations from a http url
if url:
    try:
        xml = urlopen(url)
    except HTTPError as err:
        print 'CRIT - %s' % err
        sys.exit(1)
    except URLError as err:
        print 'CRIT - %s' % err
        sys.exit(1)
elif file:
    try:
        xml = open(file)
    except Exception as err:
        print 'CRIT - %s' % err
        sys.exit(1)
else:
    print 'UNKNOWN - No XML URL/File or no Xpath search passed.\n'
    parser.print_help()
    sys.exit(3)

# Variable that will receive the XML content
xmltree = elt.ElementTree(file=xml)
output = []

# Defining the XML nodes parents and childs
# based on the search made
if childNode:
    for node in childNode.split(':'):
        if '/' in node:
            parent = '/'.join(node.split('/')[:-1]) + '/'
            child  = node.split('/')[-1].split(',')
        else:
            parent = './'
            child  = node.split(',')

        # Loop through child nodes to define the service
        for value in child:
            node = parent + value.strip()
            if xmltree.findall(node):
                node = xmltree.findall(node)[0]
                textinfo = '%s: %s' % (node.tag, node.text)
                if levels and levels[0] != '':
                    for level in [ x.split(':') for x in levels if node.tag in x ]:
                        if float(node.text) > float(level[2]):
                            textinfo = '%s: %s (crit)' % (node.tag, node.text)
                        elif float(node.text) > float(level[1]):
                            textinfo = '%s: %s (warn)' % (node.tag, node.text)
                        perfdata.append('%s=%s;%s;%s;' % (node.tag, node.text, level[1], level[2]))
                else:
                    if not node.text.isalpha():
                        perfdata.append('%s=%s;' % (node.tag, node.text))
                result.append(textinfo)
else:
    print 'UNKNOWN - No XML URL/File or no Xpath search passed.\n'
    parser.print_help()
    sys.exit(3)


# Service state definition
for info in result:
    if '(crit)' in info:
        status = (2, 'CRIT')
        break
    elif '(warn)' in info:
        status = (1, 'WARN')
        break
    else:
        status = (0, 'OK')
        break

# Printing the result
if perf:
    print '%s - %s | %s' % (status[1], ', '.join(result), ' '.join(perfdata))
else:
    print '%s - %s' % (status[1], ', '.join(result))

# Exiting based on the status number
sys.exit(status[0])