Hello wise monks. I've got problem using GraphViz within apache. In command line mode, this module works pretty well and I'm really happy with it. But as a cgi within apache, it's seems impossible to make it generate anything else than a 0 sized file :(

Found a solution!! : GraphViz needs a HOME environment variable. A SetEnv HOME /tmp/ (for instance) in apache conf fixed the problem. Actually it was written in the GraphViz FAQ about the same problem under debian.

Therefore, I deeply apologize for the time you worried about this problem.

 My conf:

GraphViz 2.02

uname -a
Linux -- 2.4.20-8 #1 Thu Mar 13 17:54:28 EST 2003 i686 i686 i386 GNU/L
+inux

Apache/2.0.40
perl v5.8.0 built for i386-linux-thread-multi


Here is my CGI:

#! /usr/bin/perl -w
use GraphViz;

use CGI qw(:standard);
use CGI::Carp qw(fatalsToBrowser);


my $g = GraphViz->new( directed => 0  );

 my $europe = {
    name      =>'Europe',
    style     =>'filled',
    fillcolor =>'lightgray',
    fontname  =>'arial',
    fontsize  =>'12'
  };


$g->add_node('London' , shape => 'hexagon' , URL => 'http://www.eteve.
+net/',
cluster=> $europe );
$g->add_node('Paris', cluster => $europe );
$g->add_node('New York');
$g->add_node('LA', label => '' , style => 'invis' ,
         height => 0 ,
         width => 0 ,
         shape => 'circle' ,
         );

$g->add_node('Amsterdam', cluster => $europe);

$g->add_edge('London' => 'Paris');
$g->add_edge('London' => 'New York', label => 'Far');
$g->add_edge('Paris' => 'LA' , label => 'Very far');
$g->add_edge('LA', 'New York', label => 'Not so far');

$g->add_edge('Paris' => 'London' ,minlen => 0 , weight => 100 );

open IMG , ">/tmp/img.jpg";
binmode IMG ;
print IMG $g->as_jpeg;
close IMG ;
[download]

The problem is the image /tmp/img/jpeg is zero sized. When the GraphViz code is ran from the command line, it works perfectly.