Rails and jQuery Datatables i18n

cards.js.coffee

jQuery ->
  tableContainer = $('#cards_datatable')
  tableContainer.dataTable
    sDom: "<'row-fluid'<'span6'l><'span6'f>r>t<'row-fluid'<'span6'i><'span6'p>>",
    sPaginationType: "bootstrap"
    bProcessing: true
    bServerSide: true
    bAutoWidth:  false
    bStateSave: true
    sWrapper: "dataTables_wrapper form-inline"
    sAjaxSource: $('#cards_datatable').data('source')
    oLanguage:{
      sUrl: "datatable_i18n"
    }

datatables_controller.rb

class DatatablesController < ApplicationController
  def datatable_i18n
    if params[:locale] == 'pt-BR'
      locale = {
          'sEmptyTable' =>     'Nenhum dado encontrado na tabela',
          'sInfo' =>           'Mostrando de _START_ ate _END_ de _TOTAL_ registros',
          'sInfoEmpty' =>      'Mostrando de 0 ate 0 de 0 registros',
          'sInfoFiltered' =>   '(filtrado de _MAX_ registros no total)',
          'sInfoPostFix' =>    '',
          'sInfoThousands' =>  ',',
          'sLengthMenu' =>     '_MENU_ registros por pagina',
          'sLoadingRecords' => 'Carregando...',
          'sProcessing' =>     'Processando...',
          'sSearch' =>         'Buscar:',
          'sZeroRecords' =>    'Nenhum dado encontrado',
          'oPaginate' => {
              'sFirst' =>    'Primeiro',
              'sLast' =>     'Ultimo',
              'sNext' =>     'Seguinte',
              'sPrevious' => 'Anterior'
          },
          'oAria' => {
              'sSortAscending' =>  ': ativar ordenacaoo crescente na coluna',
              'sSortDescending' => ': ativar ordenacaoo decrescente na coluna'
          }
      }
    else
      locale = {
          'sEmptyTable'=>     'No data available in table',
          'sInfo'=>           'Showing _START_ to _END_ of _TOTAL_ entries',
          'sInfoEmpty'=>      'Showing 0 to 0 of 0 entries',
          'sInfoFiltered'=>   '(filtered from _MAX_ total entries)',
          'sInfoPostFix'=>    '',
          'sInfoThousands'=>  ',',
          'sLengthMenu'=>     '_MENU_ records per page',
          'sLoadingRecords'=> 'Loading...',
          'sProcessing'=>     'Processing...',
          'sSearch'=>         'Search:',
          'sZeroRecords'=>    'No matching records found',
          'oPaginate'=> {
              'sFirst'=>    'First',
              'sLast'=>     'Last',
              'sNext'=>     'Next',
              'sPrevious'=> 'Previous'
          },
          'oAria'=> {
              'sSortAscending'=>  ': activate to sort column ascending',
              'sSortDescending'=> ': activate to sort column descending'
          }
      }
    end
    render :json => locale
  end

end

routes.rb

Dummy::Application.routes.draw do
  scope '(:locale)', locale: /#{I18n.available_locales.join('|')}/ do
    ...
    get 'datatable_i18n', to: 'datatables#datatable_i18n'
    ...
  end

  get '*path', to: redirect("/#{I18n.default_locale}/%{path}"), constraints: lambda { |req| !req.path.starts_with? "/#{I18n.default_locale}/" }
  get '', to: redirect("/#{I18n.default_locale}")

end