gnuplot / webplot / access_cgi (E)
Make a graphReal-time counting with CGI The previous method counts Again we define the place of files firstly. However we have to distinguish $abspath='/absolute/path/to/parent_of_image/'; $webpath='/relative/path/to/parent_of_image/'; $imgfile="access.png"; $logfile='/home/www/httpd/logs/access_log'; $gnuplot='/path/to/gnuplot'; The $abspath variable is the directory which is specified by The structure of this script is the same as the previous one.
open(LOG,$logfile);
while(<LOG>){
if(/.html/){
split;
$day = substr($_[3],1,2);
$mon = substr($_[3],4,3);
$year= substr($_[3],8,4);
$count[$day]++;
}
}
close(LOG);
$day=$#count;
$count[$day+1]=$count[$day];
& make_gnuplot;
open(GNUPLOT,"| ".$gnuplot);
foreach $i (0..$#plot){ print GNUPLOT $plot[$i]; }
for($i=1;$i<=$#count;$i++){
printf(GNUPLOT "%10d%10dn",$i,$count[$i]);
}
print GNUPLOT "endn";
close(GNUPLOT);
& generate_html;
exit 0;
sub make_gnuplot{
$i=0;
$plot[$i++]=sprintf("set term png colorn");
$plot[$i++]=sprintf("set output '%s'n",$abspath.$imgfile);
$plot[$i++]=sprintf("set size 0.7,0.7n");
$plot[$i++]=sprintf("set xrange [0:32]n");
$plot[$i++]=sprintf("set yrange [0:*]n");
$plot[$i++]=sprintf("set xtics 1,7,31n");
$plot[$i++]=sprintf("set mxtics 7n");
$plot[$i++]=sprintf("set nokeyn");
$plot[$i++]=sprintf("set gridn");
$plot[$i++]=sprintf("set title '%s %s'n",$mon,$year);
$plot[$i++]=sprintf("plot '-' with stepn");
}
Newly added lines are the next subroutine which generates HTML
sub generate_html{
print << "EOF";
Content-Type: text/html
<html>
<head><title> access_log stat </title></head>
<body bgcolor="white">
<center><img src="$webpath$imgfile"></center>
</body>
</html>
EOF
This perl script is copied into cgi-bin, and you make a following < a href=”/cgi-bin/webplot_cgi.pl/”> Web Plot </a>
Since browsers cache image files generally, and if the file name is  |
