Javascript file for ajax sign in Ruby

csrf_ajax_setup.js

$(window).load(function(){
  (function(jQuery) {
    $.ajaxSetup({
      beforeSend: function(xhr) {
        var token = jQuery('meta[name="_csrf"]').attr('content');
        xhr.setRequestHeader('X-CSRF-Token', token);
      }
    });
  }(jQuery));
});