Rails 3.1 Replacement for RXML Template Builder

Question

What is the correct way of handling custom XML responses in Rails 3.1?

In Rails 2 I had the following action in my controller:

# GET the blog as a feed
def feed
  @blog = Blog.find(:first, :id => params[:id]])

  @blog_id = @blog.id
  @blog_posts = BlogPost.find(:all, :conditions => ["blog_id = ? AND is_complete = ?", @blog_id, true], :order => "blog_posts.created_at DESC", :limit => 15)
  render :action => :feed, :layout => false
end

And then a RXML builder template in the view, 'feed.rxml':

xml.instruct! :xml, :version=>"1.0"
xml.rss(:version=>"2.0") {
xml.channel {
    xml.title(@blog.title)  
    xml.link(url_for(:only_path => false))

    xml.description(@blog.subtitle)  
    xml.language('en-us')  
    for blog_post in @blog_posts
        xml.item do  
            xml.title(blog_post.title || '')  
            xml.link(blog_named_link(blog_post))
            xml.description(blog_post.body)  
            xml.tag(blog_post.tag_string)  
            xml.posted_by(blog_post.posted_by.name)  
        end  
     end  
    }
}

Rails 3.1 has eliminated the RXML template handler but I can't seem to find documentation on what we should replace it with.

Answer 1

First add respond_to section to your action method

respond_to do |format|
  format.xml
end

or just add respond_to :html, :xml inside controller class definition

Then rename the template file to feed.xml.builder

Answer 2

ShiningRay's answer was almost 100% for me, but I had to also force it to not render the default layout in order to make the xml valid.

# force this to render as xml - this method *only* does xml
request.format = "xml" 
respond_to do |format|
  format.xml {render :layout => false} 
end