ruby-on-rails – 如何在Rails 3中创建原子提要？

我尝试通过两个步骤完成此任务：

添加了<％= auto_discovery_link_tag(：atom)％>到我的/views/layouts/application.html.erb文件.

创建了/views/posts/index.atom.builder文件.该文件包含：

atom_feed do |feed|   
  feed.title("Daily Deal")   
  feed.updated(@posts.first.created_at)
  @posts.each do |post|
    feed.entry(post) do |entry|
      entry.title(post.title)
      entry.content(post.body,:type => 'html')
      entry.author { |author| author.name("Justin Zollars")}
    end
  end
end

我在浏览器中看到了RSS链接,但链接打开时出现错误：

Too many redirects occurred trying to open
  “feed:http://localhost:3000/posts”.
  This might occur if you open a page
  that is redirected to open another
  page which then is redirected to open
  the original page.

我哪里出错了？