JSONP Proxy with Mojolicious::Lite

jsonp_proxy.pl

#!/usr/bin/perl

use strict;
use warnings;
use utf8;
use feature ':5.10';
use Encode;
use Mojolicious::Lite;
use XML::Simple;
use JSON::Any;

my $ua = Mojo::UserAgent->new;

get '/' => sub{ shift->render(text => 'ok') };
get '/:type' => sub{
     my $self = shift;
     my $type = $self->param('type');
     my $uri = $self->param('uri');
     my $callback = $self->param('callback');

     my $res = $ua->get($uri)->res;
     my $json = to_json($res, $type, $callback);
     if($callback){
          $self->res->headers->content_type('application/javascript; charset=UTF-8;');
     }else{
          $self->res->headers->content_type('application/json; charset=UTF-8;');
     }
     $self->render_data(encode('utf-8', $json));
};

sub to_json {
     my $res = shift;
     my $type = shift;
     my $callback = shift;
     my $obj = to_obj($res->body, $type);
     my $j = JSON::Any->new(utf8 => 1);
     my $ret = $callback ? $callback . '(' . $j->encode($obj) . ')' : $j->encode($obj);
     return $ret;
}

sub to_obj{
     my $txt = shift;
     my $type = shift;
     my $ret;
     given ($type){
          when ('xml') {
               $ret = XMLin(decode('utf-8', $txt));
          }
          default {
               $ret = '';
          }
     }
     return $ret;
}

app->start;