Webby helper to convert links to absolute URLs

absurl.rb

module AbsoluteUrlHelper
  def abs_url( input, dir )
    return input unless SITE.base
    return SITE.base + input if input[0,1] == '/'
    
    rgxp = %r/(src|href)="([^"]*)"/
    
    input.gsub!(rgxp) do
      path = $2
      path = URI.join(SITE.base, "/#{dir}/" ,path)
      %Q(#{$1}="#{path}")
    end
    
    return input
  end
end

Webby::Helpers.register(AbsoluteUrlHelper)

feed.txt

---
subtitle:  
author:    Your Name
email:     [email protected]
extension: xml
layout:    nil
dirty:     true
filter:    erb
---
<?xml version="1.0" encoding="utf-8"?>
<feed xmlns="http://www.w3.org/2005/Atom">
 
  <title><%= h(SITE.name) %></title>
  <subtitle><%= h(@page.subtitle) %></subtitle>
  <link href="<%= SITE.base %>/feed" rel="self" />
  <link href="<%= SITE.base %>/" />
  <updated><%= Time.now.xmlschema %></updated>
  <author>
    <name><%= h(@page.author) %></name>
    <email><%= h(@page.email) %></email>
  </author>
  <id><%= SITE.base %>/feed</id>
  <% @pages.find(:limit => 10,
                 :in_directory => 'posts',
                 :layout => 'post',
                 :recursive => true,
                 :sort_by => 'created_at',
                 :reverse => true).each do |post|
    next if post == @page
  %>
  <entry>
    <title><%= h(post.title) %></title>
    <link href="<%= SITE.base + post.url %>" />
    <id>tag:yourdomain.com,<%= post.created_at.strftime('%Y-%m-%d') %>:<%= post.created_at.to_i %></id>
    <updated><%= post.created_at.xmlschema %></updated>
    <content type="html"><%= h(abs_url(render(post), post.dir)) %></content>
  </entry>
  <% end %>
</feed>

SITEFILE

# Define the base URL in the sitefile
SITE.base = 'http://yourdomain.com'