#!/usr/bin/perl
use 5.016;
use warnings;
use Data::Diver qw{ Dive };
use Data::Dumper;

my $external_structure = {
  'name' => 'Test product',
  'id'   => 'ABC123',
  'data' => {
    'enabled'     => '1',
    'internal_id' => '',
    'urls'        => {
      'main_url' => ''
    },
    'price'     => '1000',
    'unit'      => 'ST',
    'unit_info' => {
      'qty'  => '1',
      'gtin' => '1234567890'
    }
  }
};

my %format = (
  product_id     => ['id'],
  price_excl_vat => [qw[ data price ]],
  unit_qty       => [qw[ data unit_info qty ]]
);    # (1)

my $internal_structure = {};
for my $key ( keys %format ) {
  $internal_structure->{$key} =
    Dive( $external_structure, @{ $format{$key} } );
}

print Dumper $internal_structure;

__END__
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