box-o-sand/rails/map-mash/app/models/map.rb

require 'fastercsv'


class Map < ActiveRecord::Base
  def self.from_city_name(city_name)
    self.find_or_initialize_by_name(city_name).save!
  end

  def self.rand(count = 2)
    self.find(:all, :order => 'RANDOM()', :limit => count)
  end

  def self.import(csv_filename)
    FasterCSV.parse(open(csv_filename), :headers => true,
        :header_converters => [:downcase, :symbol]).each do |row|
      map = self.find_or_initialize_by_name(
        "#{row[:city]}, #{row[:country]}"
      )
      map.save
      if block_given?
        yield map
      end
    end
  end
end