Using PHP session upload progress with Laravel

Question

I'd like to show users the progress of their uploads without using third party plugins, and I know PHP 5.4 has the ability to report upload progress through the session. Unfortunately, Laravel 4.2 doesn't use native PHP sessions, so how could I get this to work?

I've tried placing session_start() at the top of the controller methods of all the related pages (the upload form page, the post page, and the upload progress page). The upload progress function I use just returns the session as a json object, but what I get when I ajax it is an empty object. Here's some code:

In the controller:

public function test(){
    session_start();
    return View::make('admin.test');
}

public function postTest(){
    session_start();
}
public function getTestProgress(){
    session_start();
    $key = ini_get("session.upload_progress.prefix") . "fileupload";
    return Response::json($_SESSION);
}

My test view:

@extends('layouts.master')

@section('head')
<style type="text/css">
#barBlank {
  border: solid 1px #fff;
  height: 20px;
  width: 300px;
}

#barColor {
  background-color: yellow;
  height: 20px;
  width: 0px;
}

#barBlank, #hiddenUploadIframe {
  display: none;
}
</style>
@stop

@section('header')
@stop

@section('content')

<div id="barBlank">
   <div id="barColor"></div>
</div>
<div id="status"></div>
{{ Form::open( ['action' => 'MyController@postTest', 'id' => 'fileUpload', 'files' => true, 'target'=>'hiddenUploadIframe'] ) }}
<input type="hidden" value="fileupload" name="{{ ini_get('session.upload_progress.name') }}">
<input type="file" name="userfile"><br>
<input type="submit" value="Start Upload">
{{ Form::close() }}
<iframe id="hiddenUploadIframe" name="hiddenUploadIframe" src="about:blank"></iframe>

@stop

@section('footer')
@stop

@section('footerjs')
<script type="text/javascript">

function sendRequest(){
  $.get("{{ action('MyController@getTestProgress') }}", function(data){
    console.log(data);
    var progress = data.upload_progress_fileupload;
    var percent = Math.round((progress.bytes_processed / progress.content_length)*100);
    $('#barColor').width(percent+'%');
    $('#status').html(percent+'%');
    if( percent < 100 ){
      setTimeout(sendRequest(), 100);
    }
    else{
      $('#barBlank').hide();
      $('#status').html('Done.');
    }
  });
}

$('#fileUpload').submit(function(){
  $('#barBlank').css('display', 'block');
    setTimeout(sendRequest(), 100);
})

</script>
@stop