use warnings;
use strict;
use autodie;
use JSON;
use 5.010;

my @order = qw/id disp ver auth/;

my $dat = [ ({ id => 'a', disp => 'a', ver => 'a', auth => 'a' })x2 ]; # dummy data

local $\ = "\n";

print 'Unsorted => ', JSON->new->indent->space_after->encode( $dat );
print 'Alpha Sorted => ', JSON->new->indent->space_after->canonical->encode( $dat );
print 'My Order => ', manual_ordered_json( $dat, \@order );

use Data::Dumper;

sub manual_ordered_json{
    my @list = @{$_[0]};
    my @ordr = @{$_[1]};
    my $out = "[\n";
    for my $i ( 0 .. $#list ) {
        my $h = $list[$i];
        $out .= "    {\n";
        for my $j ( 0 .. $#ordr ) {
            my $k = $ordr[$j];
            next unless defined $k;
            next unless exists $h->{$k};
            $out .= sprintf qq|        "%s": "%s"|, $k, $h->{$k} // '<undef>';
            $out .= ',' if $j < $#ordr;
            $out .= "\n";
        }
        $out .= "    }";
        $out .= "," if $i < $#list;
        $out .= "\n";
    }
    $out .= "]\n";
    return $out;
}