XML on Rails

========= XML on Rails ============

sudo gem install builder

The Builder::XmlMarkup class provides methods:
cdata!(text) |	Adds a CDATA section.
comment!(comment_text)	|  Adds a comment.
declare!(inst, *args, &block)	|   Adds a declaration. args specifies 0 or more arguments.
instruct!(directive_tag=:xml, attrs={})	|  Adds a processing instruction. Attributes are specified with an array of hash entries.
new(options={})	 |  Creates an XML markup Builder object. The following options may be specified in an array of hash entries. :target=>targetObject:indent=>indentation :margin=>initial_indentation
target!()   |   Returns target of Builder object.

First, in the controller, remove the other bits in the format.xml line so it reads

respond_to do |format|
  format.xml # index.xml.builder
end

Second, you need to create an xml.builder file, in this case, index.xml.builder.
Inside the xml.builder view, you have access to an ‘xml’ object that is used to generate the xml. For example @products:

xml.instruct!
xml.SHOP do
  @products.each do |product|
    xml.SHOPITEM do
      xml.PRODUCT product.name
      xml.DESCRIPTION product.description
    end
  end
end

source:
http://www.xml.com/lpt/a/1688
http://danengle.us/2009/05/generating-custom-xml-for-your-rails-app/