#!/usr/bin/perl -w
####################### check_apachestatus_auto.pl #######################
# Version : 1.2
# Date : 14 Jul 2009 
# Author  : Dennis D. Spreen (dennis at spreendigital.de)
#						Based on check_apachestatus.pl v1.4 by 
#						  De Bodt Lieven (Lieven dot DeBodt at gmail.com)
#						    Updated by
#   						  Karsten Behrens (karsten at behrens dot in)
#		    				  Geoff McQueen (geoff dot mcqueen at hiivesystems dot com )
#				    		  Dave Steinberg (dave at redterror dot net)
#						Updated by
#							Gerhard Lausser (gerhard dot lausser at consol dot de)									
# Licence : GPL - http://www.fsf.org/licenses/gpl.txt
#############################################################
#
# help : ./check_apachestatus_auto.pl -h
#
# V1.0 Inital Release
# V1.1 Works with lighttpd server-status as well, added accesses perfdata
# V1.2 Updated perf data to be PNP compliant, added proxy option (Gerhard Lausser)

use strict;
use Getopt::Long;
use LWP::UserAgent;
use Time::HiRes qw(gettimeofday tv_interval);
use Digest::MD5 qw(md5 md5_hex);


# Nagios specific

use lib "/usr/local/nagios/libexec";
use utils qw(%ERRORS $TIMEOUT);
#my %ERRORS=('OK'=>0,'WARNING'=>1,'CRITICAL'=>2,'UNKNOWN'=>3,'DEPENDENT'=>4);


# Globals

my $Version='1.2';
my $Name=$0;

my $o_host =		undef; 		# hostname 
my $o_help=		undef; 		# want some help ?
my $o_port = 		undef; 		# port
my $o_url =		'';		# url to use, if not the default
my $o_user =		undef;		# user for auth
my $o_pass =		'';		# password for auth
my $o_realm =		'';		# password for auth
my $o_version= 		undef;  	# print version
my $o_warn_level=	undef;  	# Number of available slots that will cause a warning
my $o_crit_level=	undef;  	# Number of available slots that will cause an error
my $o_timeout=  	15;            	# Default 15s Timeout
my $o_proxy=            undef;          # proxy-url for both http and https

#my $TempPath = $ENV{HOME}.'/'; # temp path
my $TempPath = '/usr/local/nagios/';
my $MaxUptimeDif = 60*30;  # Maximum uptime difference (seconds), default 30 minutes

# functions

sub show_versioninfo { print "$Name version : $Version\n"; }

sub print_usage {
  print "Usage: $Name -H <host> [-p <port>] [-t <timeout>] [-w <warn_level> -c <crit_level>] [-V] [-u <url>] [-U user -P pass -r realm]\n";
}

# Get the alarm signal
$SIG{'ALRM'} = sub {
  print ("ERROR: Alarm signal (Nagios time-out)\n");
  exit $ERRORS{"CRITICAL"};
};

sub help {
  print "Apache Monitor for Nagios version ",$Version,"\n";
  print "GPL licence, (c)2009 Dennis D. Spreen\n\n";
  print_usage();
  print <<EOT;
-h, --help
   print this help message
-H, --hostname=HOST
   name or IP address of host to check
-p, --port=PORT
   Http port
-u, --url=URL
   Specific URL to use, instead of the default http://hostname/server-status
-U, --user=user
   Username for basic auth
-P, --pass=PASS
   Password for basic auth
-r, --realm=REALM
   Realm for basic auth
-X, --proxy=PROXY
   Proxy-URL for http and https (mandatory)
-t, --timeout=INTEGER
   timeout in seconds (Default: $o_timeout)
-w, --warn=MIN
   number of available slots that will cause a warning
   -1 for no warning
-c, --critical=MIN
   number of available slots that will cause an error
-V, --version
   prints version number
Note :
  The script will return
    * Without warn and critical options:
        OK       if we are able to connect to the apache server's status page,
        CRITICAL if we aren't able to connect to the apache server's status page,,
    * With warn and critical options:
        OK       if we are able to connect to the apache server's status page and #available slots > <warn_level>,
        WARNING  if we are able to connect to the apache server's status page and #available slots <= <warn_level>,
        CRITICAL if we are able to connect to the apache server's status page and #available slots <= <crit_level>,
        UNKNOWN  if we aren't able to connect to the apache server's status page

EOT
}

sub check_options {
  Getopt::Long::Configure ("bundling");
  GetOptions(
      'h'     => \$o_help,        'help'          => \$o_help,
      'H:s'   => \$o_host,        'hostname:s'	  => \$o_host,
      'u:s'   => \$o_url,         'url:s'	  => \$o_url,
      'U:s'   => \$o_user,        'user:s'	  => \$o_user,
      'P:s'   => \$o_pass,        'pass:s'	  => \$o_pass,
      'r:s'   => \$o_realm,       'realm:s'	  => \$o_realm,
      'p:i'   => \$o_port,        'port:i'	  => \$o_port,
      'V'     => \$o_version,     'version'       => \$o_version,
      'w:i'   => \$o_warn_level,  'warn:i'	  => \$o_warn_level,
      'c:i'   => \$o_crit_level,  'critical:i'	  => \$o_crit_level,
      't:i'   => \$o_timeout,     'timeout:i'     => \$o_timeout,
      'X:s'   => \$o_proxy,       'proxy:s'       => \$o_proxy,

  );


  if (defined ($o_help)) { help(); exit $ERRORS{"UNKNOWN"}};
  if (defined($o_version)) { show_versioninfo(); exit $ERRORS{"UNKNOWN"}};
  if (((defined($o_warn_level) && !defined($o_crit_level)) || 
      (!defined($o_warn_level) && defined($o_crit_level))) || 
      ((defined($o_warn_level) && defined($o_crit_level)) && 
       (($o_warn_level != -1) &&  ($o_warn_level <= $o_crit_level))
      )
     ) { 
    print "Check warn and crit!\n"; print_usage(); exit $ERRORS{"UNKNOWN"}
  }
  # Check compulsory attributes
  if (!defined($o_host)) { print_usage(); exit $ERRORS{"UNKNOWN"}};
}

########## MAIN ##########

check_options();

my $ua = LWP::UserAgent->new( protocols_allowed => ['http', 'https'], timeout => $o_timeout);
my $timing0 = [gettimeofday];
my $response = undef;
my $url = undef;
my $httpserver = 'APACHE'; #assume it is apache by default

if (($o_url =~ m/^http(s?)\:\/\//i) ){
    $url = $o_url;
}
else
{
  if (!defined($o_port)) {
    $url = 'http://' . $o_host . $o_url.'/server-status?auto';
	} else {
  	$url = 'http://' . $o_host . ':' . $o_port . $o_url.'/server-status?auto';
	}
}

my $req = HTTP::Request->new( GET => $url );
if (defined($o_user)) {
  $req->authorization_basic($o_user, $o_pass);
}

if (defined($o_proxy)) {
  if ($url =~ /^https/) {
    if ($o_proxy =~ /^http:\/\/(.*?)\/?$/) {
      $o_proxy = $1;
    }
    $ENV{HTTPS_PROXY} = $o_proxy;
  } else {
    $ua->proxy(['http'], $o_proxy);
  }
}

$response = $ua->request($req);
my $timeelapsed = tv_interval ($timing0, [gettimeofday]);

my $webcontent = undef;
if ($response->is_success) {
  $webcontent=$response->content;

  my $Uptime = 0;
	if($webcontent =~ m/Uptime: (.*?)\n/) {
	 $Uptime = $1;
  }
    
  my $TotalAccesses = 0;
	if($webcontent =~ m/Total Accesses: (.*?)\n/) {
	 $TotalAccesses = $1;
  }
  
  my $TotalKbytes = 0;
	if($webcontent =~ m/Total kBytes: (.*?)\n/) {
	 $TotalKbytes = $1;
  }
   
  my $ScoreBoard = '';
	if($webcontent =~ m/Scoreboard: (.*?)\n/) {
	 $ScoreBoard = $1;
  }
  
  my $BusyWorkers= 0;
	if($webcontent =~ m/(BusyWorkers|BusyServers): (.*?)\n/) {
	 $BusyWorkers = $2;
	 if ($1 eq 'BusyServers') {
	 	 $httpserver = 'LIGHTTPD';
	 }
  }
  
  my $IdleWorkers=0;
  if($webcontent =~ m/(IdleWorkers|IdleServers): (.*?)\n/) {
	 $IdleWorkers = $2;
  }
  
  my $TempFile = $TempPath.$o_host.'_check_apachestatus_auto'.md5_hex($url);
  my $FH;
  
  my $LastUptime = 0;
  my $LastTotalAccesses = 0;
  my $LastTotalKbytes = 0;
  
  if ((-e $TempFile) && (-r $TempFile) && (-w $TempFile))
  {
    open ($FH, '<',$TempFile) or exit $ERRORS{"CRITICAL"};
    $LastUptime = <$FH>;
    $LastTotalAccesses = <$FH>;
    $LastTotalKbytes = <$FH>;
    close ($FH);
  } 
 
  open ($FH, '>'.$TempFile) or exit $ERRORS{"CRITICAL"};
  print $FH "$Uptime\n"; 
  print $FH "$TotalAccesses\n"; 
  print $FH "$TotalKbytes\n";
  close ($FH);
  unlink $TempFile or exit $ERRORS{"CRITICAL"}; 
 
  my $ReqPerSec = 0;
  my $BytesPerReq = 0;
  my $BytesPerSec = 0;
  my $Accesses = 0;
  
  if (($Uptime>$LastUptime) && ($Uptime-$LastUptime<$MaxUptimeDif) && ($TotalAccesses>=$LastTotalAccesses) && ($TotalKbytes>=$LastTotalKbytes))
  {
  	$ReqPerSec = ($TotalAccesses-$LastTotalAccesses)/($Uptime-$LastUptime);
  	$BytesPerSec = (($TotalKbytes-$LastTotalKbytes)*1024)/($Uptime-$LastUptime);
  	
  	$Accesses = ($TotalAccesses-$LastTotalAccesses);
  	
  	if ($TotalAccesses>$LastTotalAccesses)
  	{
  	  $BytesPerReq = (($TotalKbytes-$LastTotalKbytes)*1024)/($TotalAccesses-$LastTotalAccesses);
  	}
  }
 
  my $CountOpenSlots = ($ScoreBoard =~ tr/\.//);
  my $TotalSlots = $CountOpenSlots+$IdleWorkers+$BusyWorkers;
  my $InfoData = '';
  my $PerfData = '';
 

 if ($httpserver eq 'APACHE')
 {
 	 $InfoData = sprintf ("- %.3f sec. response time, Busy/Idle %d/%d, open %d/%d, ReqPerSec %.1f, BytesPerReq %d, ".
  												"BytesPerSec %d", $timeelapsed, $BusyWorkers, $IdleWorkers, $CountOpenSlots, $TotalSlots, 
  												$ReqPerSec, $BytesPerReq, $BytesPerSec);

	 $PerfData = sprintf ("Idle=%d Busy=%d OpenSlots=%d Slots=%d Starting=%d Reading=%d Sending=%d Keepalive=%d ".
  												"DNS=%d Closing=%d Logging=%d Finishing=%d ReqPerSec=%f BytesPerReq=%d BytesPerSec=%f Accesses=%d",
  												($IdleWorkers),($BusyWorkers),($CountOpenSlots),($TotalSlots),($ScoreBoard =~ tr/S//),
  												($ScoreBoard =~ tr/R//),($ScoreBoard =~ tr/W//),($ScoreBoard =~ tr/K//),($ScoreBoard =~ tr/D//),
  												($ScoreBoard =~ tr/C//),($ScoreBoard =~ tr/L//),($ScoreBoard =~ tr/G//),
  												$ReqPerSec, $BytesPerReq,$BytesPerSec,$Accesses);
 }
 else
 {
 	 $InfoData = sprintf ("- %.3f sec. response time, Busy/Idle %d/%d, slots %d, ReqPerSec %.1f, BytesPerReq %d, ".
  												"BytesPerSec %d", $timeelapsed, $BusyWorkers, $IdleWorkers, $TotalSlots, 
  												$ReqPerSec, $BytesPerReq, $BytesPerSec);

	 $PerfData = sprintf ("Idle=%d Busy=%d Slots=%d ".
	 												 "Connect=%d Close=%d HardError=%d ".
	 												 "Read=%d ReadPost=%d Write=%d ".
	 												 "HandleRequest=%d RequestStart=%d ReqestEnd=%d ".
	 												 "ResponseStart=%d ResponseEnd=%d ".
	 												 "ReqPerSec=%f BytesPerReq=%d BytesPerSec=%f Accesses=%d",
  												($IdleWorkers),($BusyWorkers),($TotalSlots),
  												($ScoreBoard =~ tr/\.//),($ScoreBoard =~ tr/C//),($ScoreBoard =~ tr/E//),
  												($ScoreBoard =~ tr/r//),($ScoreBoard =~ tr/R//),($ScoreBoard =~ tr/W//),
  												($ScoreBoard =~ tr/h//),($ScoreBoard =~ tr/q//),($ScoreBoard =~ tr/q//),
  												($ScoreBoard =~ tr/s//),($ScoreBoard =~ tr/s//),
  												$ReqPerSec, $BytesPerReq,$BytesPerSec,$Accesses);
 } 	 						
  
  
  
  if (defined($o_crit_level) && ($o_crit_level != -1)) {
    if (($CountOpenSlots + $IdleWorkers) <= $o_crit_level) {
      print($httpserver." CRITICAL ".$InfoData.'|'.$PerfData);
      exit $ERRORS{"CRITICAL"}
    }
  } 
  if (defined($o_warn_level) && ($o_warn_level != -1)) {
    if (($CountOpenSlots + $IdleWorkers) <= $o_warn_level) {
      print($httpserver." WARNING ".$InfoData.'|'.$PerfData);
      exit $ERRORS{"WARNING"}
    }
  }

  print($httpserver." OK ".$InfoData.'|'.$PerfData);
  exit $ERRORS{"OK"}
}
else {
  if (defined($o_warn_level) || defined($o_crit_level)) {
    printf("UNKNOWN %s\n", $response->status_line);
    exit $ERRORS{"UNKNOWN"}
  } else {
    printf("CRITICAL %s\n", $response->status_line);
    exit $ERRORS{"CRITICAL"}
  }
}
