#!/usr/bin/env python
#
# Author: Troels Arvin <tra@sst.dk>
# Versioning:
# $Revision: 10797 $
# $Date: 2009-09-25 21:53:24 +0200 (Fri, 25 Sep 2009) $
#
# Copyright (c) 2009, Danish National Board of Health.
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
# * Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# * 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.
# * Neither the name of the the Danish National Board of Health nor the
# names of its contributors may be used to endorse or promote products
# derived from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY the Danish National Board of Health ''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 Danish National Board of Health 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.
# (Most of the script is wrapped in a big try-block, so that
# errors in the script are treated in a way which is interpreted
# as an UNKNOWN state in Nagios.)
try:
import sys
import os
import urllib
import email.Utils
import getopt
import time
import datetime
# ===========================================================
# Set up some initial values, and prepare a help-message
# ===========================================================
this_script = os.path.basename(__file__)
default_timeunit = 'h' # default time unit: hours
timeunit = None
def usage():
print """Usage:
%s [-h|--help] -u|--url <URL> -c|--critical <max> -w|--warning <max> -t|--timeunit <unit>
-c|--critical: Return CRITICAL if age is larger than <max> time units
-w|--warning: Return WARNING if age is larger than <max> time units
-t|--timeunit: Which time unit to use. Use
s for seconds
m for minutes
h for hours
d for days (24 hours)
w for weeks
If no unit is indicated, a unit of hours is used.
-u|--url : URL to check
Checks the indicated URL. If modification age (detected by the
Last-Modified HTTP-header) is greater larger than indicated age,
WARNING or CRITICAL is returned.
At least one of -c or -w need to be specified.
Example:
./check_http_age --url=http://example.com/somepath -c 5 -t d""" % this_script
sys.exit(3)
# ===========================================================
# Parameter handling and sanity checks
# ===========================================================
try:
options, args = getopt.getopt(sys.argv[1:],
"h:c:w:u:t:",
[
'help',
'critical=',
'warning=',
'url=',
'timeunit='
]
)
except getopt.GetoptError:
usage()
sys.exit(3)
maxage_c = None
maxage_w = None
for name, value in options:
if name in ("-h", "--help"):
usage()
if name in ('-u', '--url'):
url = value
if name in ('-t', '--timeunit'):
timeunit = value
if name in ("-c", "--critical"):
try:
maxage_c = int(value)
except Exception:
print "Unable to convert CRITICAL max-age to integer\n"
usage()
if name in ("-w", "--warning"):
try:
maxage_w = int(value)
except Exception:
print "Unable to convert WARNING max-age to integer\n"
usage()
if url is None:
print 'URL not indicated'
usage()
if maxage_w is None and maxage_c is None:
print 'neither max CRITICAL nor WARNING max-age was indicated'
usage()
if maxage_w is not None and maxage_c is not None:
if maxage_w >= maxage_c:
print 'warning-value greater or equal to critical-value'
usage()
if maxage_c is not None and maxage_c < 0:
print "max CRITICAL-age (%d) less than 0" % maxage_c
usage()
if maxage_w is not None and maxage_w < 0:
print "max WARNING-age (%d) less than 0" % maxage_w
usage()
# ===========================================================
# By now, all is sane; prepare some helper values
# ===========================================================
if timeunit is None:
timeunit = 'h'
multiplier = None
if timeunit == 's':
multiplier = 1
elif timeunit == 'm':
multiplier = 60
elif timeunit == 'h':
multiplier = 60*60
elif timeunit == 'd':
multiplier = 60*60*24
elif timeunit == 'w':
multiplier = 60*60*24*7
if multiplier is None:
print "Unknown timeunit '%s'" % timeunit
if maxage_w is not None:
max_diff_w = maxage_w * multiplier
if maxage_c is not None:
max_diff_c = maxage_c * multiplier
# ===========================================================
# Real work, part I: Fetch HTTP header, and parse datetime
# ===========================================================
headers = urllib.urlopen(url).info()
try:
lastmod = headers['Last-Modified']
except:
print "Could not find a Last-Modified value for the URL"
sys.exit(3)
try:
lastmod_t = email.Utils.mktime_tz(email.Utils.parsedate_tz(lastmod))
except:
print "Last-Modified header ('%s') could not be parsed" % lastmod
sys.exit(3)
# ==========================================================
# Real work, part II: Compare with limits
# ==========================================================
now_t = time.time()
diff_t = now_t - lastmod_t
# If the need for debugging should arise:
#print "lastmod: %s" % lastmod
#print "lastmod_t: %d" % lastmod_t
#print "now_t: %d" % now_t
#print "diff_t: %d" % diff_t
if maxage_c is not None:
maxdiff = maxage_c * multiplier
if diff_t > maxdiff:
print "CRITICAL: Modification time '%s' is older than %d %s" % (lastmod,maxage_c,timeunit)
sys.exit(2) # 2 means CRITICAL
if maxage_w is not None:
maxdiff = maxage_w * multiplier
if diff_t > maxdiff:
print "WARNING: Modification time '%s' is older than %d %s" % (lastmod,maxage_w,timeunit)
sys.exit(1) # 1 means WARNING
# ==========================================================
# Error and exit handling
# ==========================================================
except SystemExit, e:
# Special case which is needed in order to convert the return code
# from other exception handlers.
sys.exit(int(str(e)))
except:
# At this point, we don't know what's going on, so let's
# not output the details of the error into something which
# would appear in the Nagios web interface.
print "UNKNOWN - An unhandled error occurred. "
sys.stderr.write('Unhandled error: %s' % sys.exc_info()[1])
sys.exit(3)
# ==========================================================
# All well; construct return message
# ==========================================================
diff_t_hours = diff_t/(60*60) # floating point value a this point
diff_t_minutes = (diff_t_hours-int(diff_t_hours))*60
print "OK - HTTP modification age is %d hours and %d minutes" % (diff_t_hours,diff_t_minutes)
sys.exit(0)