How to extract the parameters passed from LASserver.pl in customizedperl function?

[Chi Ding <chi@xxxxxxxxx>]

Dear LAS users
    I'm customizing a LAS site for mooring data by writing my own perl 
function in the file custom.pl.
I don't know how to extract the parameters, like depth, time range, user 
selected variables etc, passed from users' web
browser in my function. I need those parameters to tell my ferret script 
to plot accordingly.
   My site is at 
http://palapa.ocean.dal.ca:8080/las/servlets/dataset?catitem=13. Right 
now everything in my ferret script is fixed, like variables, time range 
and depth. Therefore whatever you select,  eventually  it will draw a plot
with "salinity" and "temperature"measured at  surface during the range 
between 2002 Jun to 2002 Nov.
   My custom.pl file is like below, it contains a function called 
MooringTest.   
package LAS::Server::Ferret;

sub MooringTest {
   my $self = shift;

 my @vars = @{$self->{vars}};
 my $numVars = scalar @vars;
  
use IO::File;
my $log_file = 'MooringTest.log';
my $log_fh = IO::File->new($log_file,O_WRONLY|O_APPEND|O_CREAT);

use Carp ();
if ( !defined ($log_fh) )  { #if open log file  fails
   Carp::confess("File open failed!");
}

  print $log_fh @vars;
  print $log_fh $numVars;
  print $log_fh "\n";


   $self->command("go MooringTest");  # Execute the Ferret command 'go 
MooringTest'
   $self->genImage($self->{output_file});  # Generate the image
}
1;

    As you can see, I print the parameter array passed into my function 
in my log file. What I got was like this
LAS::Variable=HASH(0x88eff6c). I checked the perl document about 
LAS::Variable, and it has several methods like
getChildren(),getDataset(), getURL(). I tried to get the axes of the 
variable and the dataset information but failed.
    Can anybody help me to extract the parameters? Any information will 
be highly appreciated.
    Cheers, Ding