#!/usr/bin/perl -w
#
# graphcsv.pl: converts 2-column comma-separated value input into a directed
# graph.  This isn't very well tested. See doc to convert output. Or, you
# could just change the "as_canon" last line to "as_svg" or "as_gif".  I find
# it easier to save as "canon," the text layout output, to easily test different
# layouts.  For instance, "twopi" may work better than "dot," depending.
#
# usage: graphcsv.pl < input.csv > output.canon
#
# Make sure you apply the patch below for the perl GraphViz module
# http://www.snakelegs.org/2006/09/18/quoting-names-in-the-graphviz-perl-module/

use strict;
use GraphViz;
use Text::CSV_XS;

my $g = GraphViz->new(layout => 'dot', directed => 1, ratio => 'compress', overlap => 'false');
my $csv = Text::CSV_XS->new();

while (<>) {
    my $status = $csv->parse($_);
    my @columns = $csv->fields();
    $g->add_edge($columns[0] => $columns[1]);
}

print $g->as_canon;