use strict; use warnings; 
use Data::Dumper; 
{
my $current= {
          'version' => '2.0',
          'xmlns:media' => 'http://search.yahoo.com/mrss/',
          'fileSet' => {
                       'time' => '1499387013',
                       'fileName' => 'Atlanta_Regency.gif',
                       'emailAddress' => 'johndoe@gmail.com',
                       'requesterName' => 'John Doe',
                       'showAbbreviation' => {},
                       'zoneColor' => '0'
                     }
        };

if (exists($current->{'fileSet'}->{'showAbbreviation'}) 
    && defined ($current->{'fileSet'}->{'showAbbreviation'}) 
    && ( scalar(keys %{$current->{'fileSet'}->{'showAbbreviation'}}) >0) 
    ) {
      my $showAbbreviation = $current->{'fileSet'}->{'showAbbreviation'};
      print "Yes: showAbbreviation\n";
      print Dumper($showAbbreviation)."\n";
    } else {
      print "No: showAbbreviation\n";
    }
}

{
my $current= {
          'version' => '2.0',
          'xmlns:media' => 'http://search.yahoo.com/mrss/',
          'fileSet' => {
                       'time' => '1499387013',
                       'fileName' => 'Atlanta_Regency.gif',
                       'emailAddress' => 'johndoe@gmail.com',
                       'requesterName' => 'John Doe',
                       'showAbbreviation' => {a=>1},
                       'zoneColor' => '0'
                     }
        };

if (exists($current->{'fileSet'}->{'showAbbreviation'}) 
    && defined ($current->{'fileSet'}->{'showAbbreviation'}) 
    && ( scalar(keys %{$current->{'fileSet'}->{'showAbbreviation'}}) >0) 
    ) {
      my $showAbbreviation = $current->{'fileSet'}->{'showAbbreviation'};
      print "Yes: showAbbreviation\n";
      print Dumper($showAbbreviation)."\n";
    } else {
      print "No: showAbbreviation\n";
    }
}