How do I convert Data::Dumper output back into a Perl data structure?

Question

I was wondering if you could shed some lights regarding the code I've been doing for a couple of days.

I've been trying to convert a Perl-parsed hash back to XML using the XMLout() and XMLin() method and it has been quite successful with this format.

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

# use module
use IO::File;
use XML::Simple;
use XML::Dumper;
use Data::Dumper;
my $dump = new XML::Dumper;

my ( $data, $VAR1 );

Topology:$VAR1 = {  
   'device' => {  
    'FOC1047Z2SZ' => {  
      'ChassisID' => '2009-09',  
      'Error' => undef,  
      'Group' => {  
        'ID' => 'A1',  
        'Type' => 'Base'  
      },  
      'Model' => 'CATALYST',  
      'Name' => 'CISCO-SW1',  
      'Neighbor' => {},  
      'ProbedIP' => 'TEST',  
      'isDerived' => 0  
    }  
  },  
  'issues' => [  
    'TEST'  
  ]  
};  

# create object  
my $xml = new XML::Simple (NoAttr=>1,  
                           RootName=>'data',     
                           SuppressEmpty => 'true');  

# convert Perl array ref into XML document  
$data = $xml->XMLout($VAR1);  

#reads an XML file  
my $X_out = $xml->XMLin($data);  

# access XML data  
print Dumper($data);  
print "STATUS: $X_out->{issues}\n";  
print "CHASSIS ID: $X_out->{device}{ChassisID}\n";  
print "GROUP ID: $X_out->{device}{Group}{ID}\n";  
print "DEVICE NAME: $X_out->{device}{Name}\n";  
print "DEVICE NAME: $X_out->{device}{name}\n";  
print "ERROR: $X_out->{device}{error}\n";  

I can access all the element in the XML with no problem.

But when I try to create a file that will house the parsed hash, problem arises because I can't seem to access all the XML elements. I guess, I wasn't able to unparse the file with the following code.

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

# use module
use IO::File;  
use XML::Simple;  
use XML::Dumper;  
use Data::Dumper;  
my $dump = new XML::Dumper;  

my ( $data, $VAR1, $line_Holder );

#this is the file that contains the parsed hash  
my $saveOut = "C:/parsed_hash.txt";  
my $result_Holder = IO::File->new($saveOut, 'r');  
while ($line_Holder = $result_Holder->getline){  
    print $line_Holder;  
}  

# create object  
my $xml = new XML::Simple (NoAttr=>1, RootName=>'data', SuppressEmpty => 'true');  
# convert Perl array ref into XML document  
$data = $xml->XMLout($line_Holder);  
#reads an XML file  
my $X_out = $xml->XMLin($data);  

# access XML data  
print Dumper($data);  
print "STATUS: $X_out->{issues}\n";  
print "CHASSIS ID: $X_out->{device}{ChassisID}\n";  
print "GROUP ID: $X_out->{device}{Group}{ID}\n";  
print "DEVICE NAME: $X_out->{device}{Name}\n";  
print "DEVICE NAME: $X_out->{device}{name}\n";  
print "ERROR: $X_out->{device}{error}\n";  

Do you have any idea how I could access the $VAR1 inside the text file?

Regards,
newbee_me

Answer 1

$data = $xml->XMLout($line_Holder); 

$line_Holder has only the last line of your file, not the whole file, and not the perl hashref that would result from evaling the file. Try something like this:

my $ref = do $saveOut;

The do function loads and evals a file for you. You may want to do it in separate steps, like:

use File::Slurp "read_file";
my $fileContents = read_file( $saveOut );
my $ref = eval( $fileContents );