How to set defaults for parameters of url helper methods?

Question

I use language code as a prefix, e.g. www.mydomain.com/en/posts/1. This is what I did in routes.rb:

scope \":lang\" do
  resources :posts
end


        

Answer 1

doesterr above has almost got it. That version of default_url_options won't play nice with others. You want to augment instead of clobber options passed in:

def locale_from_cookie
  # retrieve the locale
end

def default_url_options(options = {})
  options.merge(:lang => locale_from_cookie)
end

Answer 2

This is coding from my head, so no guarantee, but give this a try in an initializer:

module MyRoutingStuff
  alias :original_url_for :url_for
  def url_for(options = {})
    options[:lang] = :en unless options[:lang]   # whatever code you want to set your default
    original_url_for
  end
end
ActionDispatch::Routing::UrlFor.send(:include, MyRoutingStuff)

or straight monkey-patch...

module ActionDispatch
  module Routing
    module UrlFor
      alias :original_url_for :url_for
      def url_for(options = {})
        options[:lang] = :en unless options[:lang]   # whatever code you want to set your default
        original_url_for
      end
    end
  end
end

The code for url_for is in actionpack/lib/routing/url_for.rb in Rails 3.0.7

Answer 3

Ryan Bates covered this in todays railscast: http://railscasts.com/episodes/138-i18n-revised

You find the source for url_for here: http://api.rubyonrails.org/classes/ActionDispatch/Routing/UrlFor.html

You will see it merges the given options with url_options, which in turn calls default_url_options.

Add the following as private methods to your application_controller.rb and you should be set.

def locale_from_cookie
  # retrieve the locale
end

def default_url_options(options = {})
  {:lang => locale_from_cookie}
end