Generating XML in a model

rubyonrails-talk
1

Hi all,

I have an application that produces an RSS feed of blog posts. To do this, I have a file rss.rxml that contains code like this:

@blogs.each do |blog|     xml.item do        xml.title blog.subject        xml.link blogs_path        xml.description blog.body        xml.guid blogs_path        xml.pubDate blog.created_at     end end

I want to move this code into a to_rss method on my Blog model, so that I can simply write:

@blogs.each do |blog|     blog.to_rss end

The idea here is that it should be really easy to add other items to my rss feed, like photos or events - my view file can then generate the feed for a collection of arbitrary objects, as long as the models all have to_rss methods.

My question is, what do I need to include in the model in order to use the xml builder? I want to write in blog.rb

def to_rss     xml.item do        xml.title self.subject        xml.link blogs_path        xml.description self.body        xml.guid blogs_path        xml.pubDate self.created_at     end end

This raises an error like "undefined variable xml". Does anyone know how to solve this?

Many thanks, Adam

2

My question is, what do I need to include in the model in order to use the xml builder? I want to write in blog.rb

def to_rss    xml.item do       xml.title self.subject       xml.link blogs_path       xml.description self.body       xml.guid blogs_path       xml.pubDate self.created_at    end end

This raises an error like "undefined variable xml". Does anyone know how to solve this?

In the context of an rxml view, an instance of Builder::XMLMarkup has
already been created for you and assigned to the local variable xml.
You just need to do the same. See also the examples at http://builder.rubyforge.org/

Fred

3

Thanks Fred - I just solved the problem by passing the xml variable to the to_rss method, and now I feel a bit silly for asking! :slight_smile: