Munin contributed plugins

#!/usr/bin/perl

# -*- perl -*-

#

# Plugin to graph http performance

# Version: 0.8.7

#

# The purpose of this plugin is to monitor several properties of a web page.

# All measurements are done for the complete web page, including images, css

# and other content a standard browser would download automatically.

#

# This version supports monitoring:

#   * The total time to download a complete web page (using serial GET requests)

#   * The total size of a web page

#   * The different response codes (200, 404, 500, etc)

#   * The different tags (img src, a href, etc)

#   * The the different content types (image/png, text/css/, etc)

#   * The number of elements the web page consists of

# 

# Author:  Espen Braastad / Linpro AS

#          espen@linpro.no

#

##### Short usage guide: #####

#

# Requirements:

#  * The server running this plugin must be allowed  to connect to the web 

#    server(s) you are going to monitor.

#  * Some perl modules: 

#    Time::HiRes, LWP::UserAgent, HTML::LinkExtor, LWP::ConnCache

#

# Initial configuration:

#  1. Copy this file to /usr/share/munin/plugins/

#

#  2. Create a file (/etc/munin/http_load_urls.txt) with one

#     full url per line, as many as you want, i.e.:

#      $ echo "http://www.dn.no/" >> /etc/munin/urls.txt

#      $ echo "http://www.intrafish.no/" >> /etc/munin/urls.txt

#

#  3. Add a cron job running the plugin with cron as the argument:

#     */15 * * * * <user> /usr/sbin/munin-run http_load_<site>_loadtime cron

#     <user> should be the user that has write permission to the $cachedir

#     directory set below. <site> should be any of the configured sites (all

#     sites will get updated), likewise, you should replace loadtime by any

#     metric that is enabled for that site (all metrics will get updated).

#     Set the intervals to whatever you want.

#

#     For verbose output (for debugging) you can do:

#     sudo -u <user> /usr/share/munin/plugins/http_load_ cron verbose

#

#  4. Run munin-node-configure --suggest --shell and run the symlink

#     commands manually to update the munin-node plugin list.

#  

# (5. If you want to change the filter which the plugin uses to select which

#     tags to follow in a web page, edit the subroutine called "filter" below.)

#

# Add a new url to monitor:

#  1. Add a new line in /etc/munin/urls.txt with the full URL, i.e.:

#      $ echo "http://www.linpro.no/" >> /etc/munin/http_load_urls.txt

#

#  2. Run munin-node-configure --suggest --shell and manually

#     add the new symlink(s)

#

#  3. /etc/init.d/munin-node restart

#

# Remove a url from monitoring:

#  1. Remove it from /etc/munin/http_load_urls.txt

#

#  2. Remove ${cachedir}/http_load_<url_id>*

#

#  3. Remove /etc/munin/plugins/http_load_<url_id>*

#

#  4. /etc/init.d/munin-node restart

#

#####

#

# Todo:

#   * Add support for forking to simulate real browsers

#   * Use checksums as fieldnames

#

# $Id: $

#

# Magic markers:

#%# family=auto

#%# capabilities=autoconf suggest

use strict;

use Time::HiRes qw( gettimeofday tv_interval );

use LWP::UserAgent;

use HTML::LinkExtor;

use LWP::ConnCache;

my $url_file="/etc/munin/http_load_urls.txt";

my $cachedir=$ENV{MUNIN_PLUGSTATE};

my $debug=$ENV{MUNIN_DEBUG};

my $timeout=10;

my $max_redirects=10;

my $scriptname="http_load_";

my $useragent="Mozilla/5.0";

# Function to read the $url_file and return the contents in a hash

sub read_urls{

	my $file=$_[0];

	my %urls=();

	if(-r $file){

		open(FILE,'<'.$file);

		while (<FILE>) { 

			my $url=$_;

			chomp($url);

			my $id=get_id($url);

			if(length($id)>0){

				$urls{$id}=$url;

			}

		}

		close (FILE);

	}

	return %urls;

}

# Function to read cache, return a hash

sub read_cache{

	my $file=$_[0];

	my %cache=();

	if(-r $file){

		open(FILE,'<'.$file);

		while (<FILE>) { 

			m/^(\S*)\s+(.*)$/;

			$cache{ $1 } = $2;

		}

		close (FILE);

	}

	return %cache;

}

# Function to filter the html tags, which files do we want to download

sub filter{

	my $tag=$_[0];

	my $status=1;

	# Some example data:

	# link href http://www.intrafish.no/template/include/css/intrafish.css

	# script src http://www.intrafish.no/template/include/js/intrafish.js

	# a href http://adserver.adtech.de/?adlink%7C2.0%7C405%7C119488%7C1%7C16%7CADTECH;grp=8491;loc=300;

	# img src http://adserver.adtech.de/?adserv%7C2.0%7C405%7C119488%7C1%7C16%7CADTECH;grp=8491;

	# area href http://go.vg.no/cgi-bin/go.cgi/sol/http://www.sol.no/sgo/vg/http://www.sol.no/underholdning/humor/?partnerid=vg

	# status=1 => do download (default)

	# status=0 => do not download

	if("$tag" eq "form action"){

		$status=0;

	}

	if("$tag" eq "a href"){

		$status=0;

	}

	if("$tag" eq "area href"){

		$status=0;

	}

	return $status;

}

# Return the cache file name for this plugin

sub get_cache_file_name{

	my $scriptname=$_[0];

	my $id=$_[1];

	my $file="";

	$file = $scriptname . $id . ".cache";

	$debug && print "Cache file: " . $file . "\n";

	return $file;

}

# Get fieldname (making sure it is munin-1.0 "compatible" as a fieldname)

# 1. Remove all non-word characters from a string)

# 2. Make sure it has maximum 19 characters

#    2.1 If not, truncate the host part, while keeping anything after an underscore (e.g., HTTP response status)

sub get_fieldname{

	my $url=$_[0];

	$url =~ s/\W//g;

	if(length($url) > 19){

		$url =~ s/(\S+)_(\S+)/ /g;

		my $host = $1;

		my $info = $2;

		my $suffixlength = length($info) + 1;

		if ($suffixlength > 1) {

			$url = substr($host, 0, 19 - $suffixlength) . '_' . $info;

		} else {

			$url = substr($url, 0, 19);

		}

	}

	return $url;

}

# Same as get_fieldname except it doesn't substr

sub get_id{

	my $url=$_[0];

	$url =~ s/[\W_]//g;

	return $url;

}

$debug && print "Scriptname: " . $scriptname . "\n";

# Get the url id and the type of the graph

#

# The filename format is http_load_X_Y where

# X: The line number in urls.txt

# Y: The type of graph (elements, size, loadtime, ..)

my ($id,$type);

$0 =~ /http_load(?:_([^_]+)|)_(.+)\s*$/;

$id  = $1;

$type = $2;

$debug && print "Id: $id, Type: $type\n";

if($ARGV[0] and $ARGV[0] eq "autoconf") {

	my %urls=&read_urls($url_file);

	if(keys(%urls) gt 0){

		print "yes\n";

		exit(0);

	} else {

		print "no\n";

		exit(1);

	}

} elsif($ARGV[0] and $ARGV[0] eq "suggest") {

	# get the url list, print suggestions for usage

	my %urls=&read_urls($url_file);

	while ( my ($id, $url) = each(%urls) ) {

        	$debug && print "id: $id => url: $url\n";

        	print $id . "_size\n";

        	print $id . "_loadtime\n";

        	print $id . "_response\n";

        	print $id . "_tags\n";

        	print $id . "_type\n";

        	print $id . "_elements\n";

    	}

	exit(0);

} elsif($ARGV[0] and $ARGV[0] eq "cron") {

	# This thing is run by cron and should write a cache file for munin-node to 

	# read from

	my $verbose=0;

	if(

		$ENV{MUNIN_DEBUG} eq "1" or

		$ARGV[1] and $ARGV[1] eq "verbose"

	) {

		$verbose=1;

		print "Verbose output\n";

	}

	my %urls=&read_urls($url_file);

	my %output;

	my %res;

	my $t0;

	my ($request,$response,$status,$link,$contents,$page_parser,$cachefile);

	while ( my ($id, $url) = each(%urls) ) {

        	$verbose && print "Fetching $url (id: $id)... \n";

		$t0=0;

		$status=0;

		%output=();

		my $host="";

		if($url =~ m/\w+\:\/\/([^\/]+).*/){

			$host=$1;

        		$verbose && print " Host: $host\n";

		}

		$output{"url"}=$url;

		$output{"timestamp"}=time();

        	$verbose && print " Timestamp: " . $output{"timestamp"} . "\n";

	        my $browser = LWP::UserAgent->new();

		$browser->agent($useragent);

	        $browser->timeout(${timeout});

		$browser->max_redirect( $max_redirects );

		$browser->conn_cache(LWP::ConnCache->new());

		$response = $browser->get($url);

		# Calculating time from now:

		$t0 = [gettimeofday];

	        if ($response->is_success()) {

	                $status=1;

			$output{"elements_" . $host}+=1;

	        }

        	$contents = $response->content();

	        $output{"loadtime_" . $host} += sprintf("%.6f",tv_interval ( $t0, [gettimeofday]));

        	$output{"size_" . $host}+=length($contents);

		$output{"response_" . $host . "_" . $response->code}+=1;

		$output{"type_" . $response->content_type}+=1;

	        $page_parser = HTML::LinkExtor->new(undef, $url);

	        $page_parser->parse($contents)->eof;

	        my @links = $page_parser->links;

        	$verbose && print " Processing links:\n";

        	%res=();

	        foreach $link (@links){

			my $tag=$$link[0] . " " . $$link[1];

			$output{"tags_" . $$link[0] . "-" . $$link[1]}+=1;

			if(filter($tag)){

				$verbose && print "  Processing: " . $$link[0] . " " . $$link[1] . " " . $$link[2] . "\n";

				# Extract the hostname and add it to the hash

				if($$link[2] =~ m/http\:\/\/([^\/]+).*/){

					$host=$1;

					$output{"elements_" . $host}+=1;

				}

                	        my $suburl=$$link[2];

				$t0 = [gettimeofday];

				$response = $browser->get($suburl);

	        		$output{"loadtime_" . $host} += sprintf("%.6f",tv_interval ( $t0, [gettimeofday]));

        			$contents = $response->content();

        			$output{"size_" . $host}+=length($contents);

				$output{"response_" . $host . "_" . $response->code}+=1;

				$output{"type_" . $response->content_type}+=1;

				$verbose && print "              Response: " . $response->code . " Size: " . length($contents) . "\n";

			} else {

				$verbose && print "  Skipping:   " . $$link[0] . " " . $$link[1] . " " . $$link[2] . "\n";

			}

		}

		$cachefile=$cachedir . "/" . &get_cache_file_name($scriptname,$id);

		$debug && print "Reading cache file: " . $cachefile . "... ";

		my %input=read_cache($cachefile);

		$debug && print "done\n";

		# Resetting all values to 0 before adding new values

		while ( my ($id, $value) = each(%input) ) {

			$input{$id}="U";

    		}

		# Adding new values

		while ( my ($id, $value) = each(%output) ) {

			$input{$id}=$value;

        		$verbose && print " Result: " . $id . " -> " . $value . "\n";

    		}

		# Writing the cache

		$verbose && print "Writing cache file: " . $cachefile . "... ";

		open(FILE,">".$cachefile);

		while ( my ($id, $value) = each(%input) ) {

			print FILE $id . " " . $value . "\n";

		}

		close(FILE);

		$verbose && print "done\n";

	}

	exit(0);

}elsif($ARGV[0] and $ARGV[0] eq "config") {

	my %urls=&read_urls($url_file);

        print "graph_title $urls{$id} ${type}\n";

        print "graph_args -l 0 --base 1000\n";

        print "graph_category webserver\n";

	$debug && print "Reading cache file\n";

	my $cachefile=$cachedir . "/" . &get_cache_file_name($scriptname,$id);

	my %cache=read_cache($cachefile);

	my $count=0;

	$debug && print "The cache file contains " . keys(%cache) . " lines\n";

	if($type eq "size"){

                print "graph_vlabel Bytes\n";

		print "graph_total Total\n";

         	print "graph_info This graph is generated by a set of serial GETs to calculate the total size of $urls{$id}.\n";

		if(keys(%cache)>0){

			for my $key ( sort reverse keys %cache ){

				my $value=$cache{$key};

				if($key =~ m/^size_(\S+)$/){

					my $host=$1;

					my $value=$value;

					my $name=$1;

					$name=get_fieldname($name);

        	        		print "$name.label from $host\n";

        	        		print "$name.min 0\n";

        	        		print "$name.max 20000000\n";

					if($count eq 0){

						print "$name.draw AREA\n";

					} else {

						print "$name.draw STACK\n";

					}

					$count+=1;

				}

			}

		}

	}elsif($type eq "loadtime"){

                print "graph_vlabel Seconds\n";

		print "graph_total Total\n";

         	print "graph_info This graph is generated by a set of serial GETs to calculate the total time to load $urls{$id}. ";

		print "Note that browsers usually fork() the GET requests, resulting in a shorter total loading time.\n";

		if(keys(%cache)>0){

			for my $key ( sort reverse keys %cache ){

				my $value=$cache{$key};

				if($key =~ m/^loadtime_(\S+)$/){

					my $host=$1;

					my $value=$value;

					my $name=$1;

					$name=get_fieldname($name);

        	        		print "$name.label from $host\n";

        	        		print "$name.min 0\n";

        	        		print "$name.max 400\n";

					if($count eq 0){

						print "$name.draw AREA\n";

					} else {

						print "$name.draw STACK\n";

					}

					$count+=1;

				}

			}

		}

	}elsif($type eq "elements"){

                print "graph_vlabel Number of elements\n";

		print "graph_total Total\n";

        	print "graph_info This graph is generated by a set of serial GETs to count the number of elements (images, CSS files, etc) from $urls{$id}.\n";

		if(keys(%cache)>0){

			for my $key ( sort reverse keys %cache ){

				my $value=$cache{$key};

				if($key =~ m/^elements_(\S+)$/){

					my $host=$1;

					my $value=$value;

					my $name=$1;

					$name=get_fieldname($name);

        	        		print "$name.label from $host\n";

        	        		print "$name.min 0\n";

        	        		print "$name.max 10000\n";

					if($count eq 0){

						print "$name.draw AREA\n";

					} else {

						print "$name.draw STACK\n";

					}

					$count+=1;

				}

			}

		}

	}elsif($type eq "response"){

                print "graph_vlabel Server response code count\n";

		print "graph_total Total\n";

         	print "graph_info This graph is generated by a set of serial GETs to visualize the server response codes received while loading $urls{$id}.\n";

		if(keys(%cache)>0){

			for my $key ( sort reverse keys %cache ){

				my $value=$cache{$key};

				if($key =~ m/^response_(\S+)$/){

					my $host=$1;

					my $value=$value;

					my $name=$1;

					$name=get_fieldname($name);

					$host =~ s/\_/ /g;

					$host =~ s/(\S+)\s(\d+)/ /g;

					$host=$1;

					my $code=$2;

        	        		print "$name.label $host ($code)\n";

        	        		print "$name.min 0\n";

        	        		print "$name.max 10000\n";

					if($count eq 0){

						print "$name.draw AREA\n";

					} else {

						print "$name.draw STACK\n";

					}

					$count+=1;

				}

			}

		}

	}elsif($type eq "type"){

                print "graph_vlabel Content type count\n";

		print "graph_total Total\n";

         	print "graph_info This graph is generated by a set of serial GETs to visualize the different content types $urls{$id} consists of.\n";

		if(keys(%cache)>0){

			for my $key ( sort reverse keys %cache ){

				my $value=$cache{$key};

				if($key =~ m/^type_(\S+)$/){

					my $type=$1;

					my $value=$value;

					my $name=$1;

					$name=get_fieldname($name);

					#$host =~ s/\_/ /g;

					#$host =~ s/(\S+)\s(\S+)/ /g;

					#$host=$1;

					#my $type=$2;

        	        		print "$name.label $type\n";

        	        		print "$name.min 0\n";

        	        		print "$name.max 100000\n";

					if($count eq 0){

						print "$name.draw AREA\n";

					} else {

						print "$name.draw STACK\n";

					}

					$count+=1;

				}

			}

		}

	}elsif($type eq "tags"){

                print "graph_vlabel HTML tag count\n";

		print "graph_total Total\n";

         	print "graph_info This graph is generated by a set of serial GETs to visualize the different tags $urls{$id} consists of.\n";

		if(keys(%cache)>0){

			for my $key ( sort reverse keys %cache ){

				my $value=$cache{$key};

				if($key =~ m/^tags_(\S+)$/){

					my $host=$1;

					my $value=$value;

					my $name=$1;

					$name=get_fieldname($name);

					$host =~ s/\W/ /g;

        	        		print "$name.label $host\n";

        	        		print "$name.min 0\n";

        	        		print "$name.max 100000\n";

					if($count eq 0){

						print "$name.draw AREA\n";

					} else {

						print "$name.draw STACK\n";

					}

					$count+=1;

				}

			}

		}

	}

	exit(0); 

} else {

	my $cachefile=$cachedir . "/" . &get_cache_file_name($scriptname,$id);

	$debug && print "Reading cache file: " . $cachefile . "\n";

	my %cache=read_cache($cachefile);

	$debug && print "Number of lines in cache file: " . keys(%cache) . "\n";

	if(keys(%cache)>0){

		for my $key ( sort keys %cache ){

			my $value=$cache{$key};

			if($key =~ m/^([A-Za-z]+)\_(\S+)$/){

				my $name=$2;

				if ($1 eq $type){

					$name=get_fieldname($name);

					print $name . ".value " . $value . "\n";

				}

			} elsif(m/^(\S+)\s+(\S+)$/){

				if ($1 eq $type){

					print $1 . ".value " . $2 . "\n";

				}

			}

		}

	}

} 

# vim:syntax=perl