panel/app/assets/javascripts/drag.js

$(document).on('turbolinks:load', function() {
  tableDragger(document.querySelector('.table-draggable'), {
    mode: 'row',
    onlyBody: true,
    dragHandler: '.handle'
  }).on('drop', function(from, to, el, mode) {
    // Al soltar, reordenamos toda la tabla
    $('.post_order').val(function(i,v) { return i; });
  });
});