Example 'Comma' gem CSV use

# demo of adding a CSV description to any arbitrary object using the 'comma' gem
#
# http://github.com/crafterm/comma for more info

class Book < ActiveRecord::Base

  # ================
  # = Associations =
  # ================
  has_many   :pages
  has_one    :isbn
  belongs_to :publisher

  # ===============
  # = CSV support =
  # ===============
  comma do

    name
    description

    pages :size => 'Pages'
    publisher :name
    isbn :number_10 => 'ISBN-10', :number_13 => 'ISBN-13'
    url 'Website'

  end

end

# ... and if you're using Rails, render supports a :csv modifier

class BooksController < ApplicationController

  def index
    render :csv => Book.limited(50)
  end

end