#!/usr/bin/ruby

# Relay the status of a check that was previously run and which stored
# its result in a file to nagios.
#
# Copyright 2008 Peter Palfrader
#
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to
# the following conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

require 'resolv'
require 'optparse'

NAGIOS_STATUS = { "OK" => 0, "WARNING" => 1, "CRITICAL" => 2, "UNKNOWN" => 3 }
UNITS_TO_SECONDS = { 's' => 1, 'm' => 60, 'h' => 60*60, 'd' => 24*60*60 }

def show_help(parser, code=0, io=STDOUT)
  program_name = File.basename($0, '.*')
  io.puts "Usage: #{program_name} [options] <statusfile>"
  io.puts parser.summarize
  exit(code)
end

max_age = "26h"
ARGV.options do |opts|
        opts.on_tail("-h", "--help" , "Display this help screen")                                               { show_help(opts) }
        opts.on("-a", "--age=AGE"  , String, "maximum age, in seconds (or use Nm, Nh or Nd) - default is 26h")  { |max_age| }
        opts.parse!
end
show_help(ARGV.options, 1, STDERR) if ARGV.length != 1

statusfile = ARGV.shift

# find out what the max age is that we accept
unless (m = /^([0-9]+)([smhd])?$/.match max_age)
	STDERR.puts "Invalid age #{age}."
	show_help(ARGV.options, 1, STDERR) if ARGV.length != 1
end
max_age = m[1].to_i * UNITS_TO_SECONDS[m[2] ? m[2] : 's']

# let's see if it exists
unless File.exists? statusfile
	puts "UNKNOWN: #{statusfile} does not exist."
	exit NAGIOS_STATUS['UNKNOWN']
end


mtime = File.stat(statusfile).mtime
if mtime + max_age < Time.now
	puts "WARNING: #{statusfile} is old: #{mtime}"
	exit NAGIOS_STATUS['WARNING']
end

status = File.new(statusfile)
returnvalue = status.readline.chomp

unless NAGIOS_STATUS.has_key? returnvalue
	puts "UNKNOWN: #{statusfile} has invalid return value: #{returnvalue}"
	exit NAGIOS_STATUS['UNKNOWN']
end

status.readlines.each do |line|
	print line
end
exit NAGIOS_STATUS[returnvalue]