Datamapper Book class that works with isbndb.com

book.rb

require 'hpricot'
require 'open-uri'

class Book
  include DataMapper::Resource
  
  validates_is_unique :isbn
  
  property :id, Serial
  property :title, String
  property :title_long, String
  property :isbn, String
  property :author, String
  property :publisher_text, String
  
  def self.find_by_isbn(isbn)
    book = Book.first(:isbn => isbn)
    unless book
      book = Book.new(:isbn => isbn)
      doc = Hpricot.parse(open("http://isbndb.com/api/books.xml?access_key=#{Book.access_key}&index1=isbn&value1=#{isbn}"))
      book.title = (doc/:title)[0].inner_text
      book.title_long = (doc/:titlelong)[0].inner_text
      book.author = (doc/:authorstext)[0].inner_text
      book.publisher_text = (doc/:publishertext)[0].inner_text
      book.save
    end
    book
  end

  def self.access_key
    # YOUR ISBNDB.COM ACCESS KEY HERE
  end
end