Redirect non-www requests to www URLs in Ruby on Rails

Question

It is a simple issue, but I can\'t seem to find an answer doing some quick googling.

What\'s the Ruby on Rails way of doing this 301 direct (http://x.com/abc > http:

Answer 1

Ideally you'd do this in your web server (Apache, nginx etc.) configuation so that the request doesn't even touch Rails at all.

Add the following before_filter to your ApplicationController:

class ApplicationController < ActionController::Base
  before_filter :add_www_subdomain

  private
  def add_www_subdomain
    unless /^www/.match(request.host)
      redirect_to("#{request.protocol}x.com#{request.request_uri}",
                  :status => 301)
    end
  end
end

If you did want to do the redirect using Apache, you could use this:

RewriteEngine on
RewriteCond %{HTTP_HOST} !^www\.x\.com [NC]
RewriteRule ^(.*)$ http://www.x.com/$1 [R=301,L]