How to change the locale through URL?

Question

In my bi-lingual Rails 4 application I have a LocalesController like this:

class LocalesController < ApplicationController

  def change_loca         


        

Answer 1

Maybe it's better to set locale in routes.rb like this:

# config/routes.rb
scope "(:locale)", locale: /en|nl/ do
  resources :books
end

You can read more here http://guides.rubyonrails.org/i18n.html#setting-the-locale-from-the-url-params

UPD. If you also save locale to the session, you also need to update it on each request. You can set it in the filter as suggested in the other answer. But I prefer to use less filters:

def locale_for_request
  locale = params[:locale]
  if locale && I18n.locale_available?(locale)
    session[:locale] = locale
  else
    session[:locale] || I18n.default_locale
  end
end

# then use it in the around filter: I18n.with_locale(locale_for_request)