title: AJAX post JSOSN data arrives empty - codeigniter
body: <p>I have found a lot of similar questions, yet no one is related to my question, however, This is my AJAX request</p>
  
  <pre><code>data = JSON.stringify(data);
  url = base_url + "index.php/home/make_order";
  //alert(url);
  
  var request = $.ajax({
    url: url,
    type: 'POST',
    contentType: 'application/json',
    data: data
  });
  request.done(function(response){
    alert('success');
  });
  request.fail(function(jqXHR, textStatus, errorThrown){
    alert('FAILED! ERROR: ' + errorThrown);
  });
  </code></pre>
  
  <p>My problem is that when it arrives to the PHP CI-controller <strong>$this->input->post('data')</strong> arrives <strong>empty</strong>!!</p>
  
  <p><strong>UPDATE</strong>
  This is my data: as shown before the AJAX request:</p>
  
  <blockquote>
    <p>data = {"sum":"2.250","info":[{"id":"6","name":"bla","price":"1.000"}]}</p>
  </blockquote>
  
  <p>Please help. Thanks in advance.</p>