check_memory

#!/usr/bin/python

import os
import re
import sys
from optparse import OptionParser

# mem.used as mem.total - mem.free
UNKNOWN = 3
OK = 0
WARNING = 1 #optional
CRITICAL = 2


PROC = '/proc/meminfo'


def CalulateIT():
    with open(PROC) as f:
        for line in f.readlines():
            MemTotal = re.search(r'^MemTotal:\s+(\d+)', line)
            MemFree = re.search(r'^MemFree:\s+(\d+)', line)
            if MemTotal:
                mem_total_kB = int(MemTotal.groups()[0])
            if MemFree:
                mem_free_kB = int(MemFree.groups()[0])
    mem_used_kB = mem_total_kB - mem_free_kB
    return 100 * mem_used_kB/mem_total_kB

def main():
    parser = OptionParser()
    parser.add_option('-c', '--critical', dest='critical', help='critical threshold in percent', type=int)
    parser.add_option('-w', '--warning', dest='warning', help='warning threshold in percent', type=int)
    (options, args) = parser.parse_args()
    if not options.critical is None:
        if not os.path.exists(PROC) and not os.access(PROC, os.R_OK):
            print "This check can only be ran on linux"
            sys.exit(UNKNOWN)
        percent_used_kB = CalulateIT()
        if percent_used_kB >= options.critical:
             print "CRICICAL: Used Memory %s has reach critical threshold of %s" %(percent_used_kB,options.critical)
             sys.exit(CRITICAL)
        if not options.warning is None:
            if percent_used_kB >= options.warning:
                print "WARNING: Used Memory %s has reach warning threshold of %s" %(percent_used_kB,options.warning)
                sys.exit(WARNING)
        if percent_used_kB <= options.critical:
             if options.warning:
                 print "OK: Used Memory %s is below warning threshold %s" %(percent_used_kB,options.warning)
             else:
                 print "OK: Used Memory %s is below critical threshold %s" %(percent_used_kB,options.critical)

             sys.exit(OK)
    else:
        print "Please add the percent threshold, example: -c 80"
        print "The Warning (-w) is optional"
        print "Ex: %s -w 80 -c 90" %os.path.basename(__file__)
        sys.exit(UNKNOWN)

if __name__ == '__main__':
    main()