gistfile1.txt

class ApplicationController < ActionController::Base
  protect_from_forgery with: :exception

  before_filter :set_locale

  private

  def set_locale
    if params[:locale]
      I18n.locale = params[:locale]
      session[:locale] = params[:locale]
    elsif session[:locale]
      I18n.locale = session[:locale]
    else
      I18n.locale = http_accept_language
        .compatible_language_from(I18n.available_locales)
    end
  end
end