dm-is-cloneable

A DataMapper plugin that adds the ability to clone any model.
As this alone wouldn’t really be a big deal, it is also possible
to specifiy a 1:n relation with so called clone_specs_. In these,
the @attributes_toclone@ are persisted, thus leaving clients with
the choice of selecting predefined sets of attributes to clone.

require 'rubygems'

gem 'dm-core',         '=0.9.11'
gem 'dm-validations',  '=0.9.11'
gem 'dm-is-remixable', '=0.9.11'
gem 'dm-is-cloneable', '=0.0.1'

require 'dm-core'
require 'dm-validations'
require 'dm-is-remixable'
require 'dm-is-cloneable'

DataMapper::Logger.new(STDOUT, :debug)

DataMapper.setup(:default, 'sqlite3:memory:')


class Item

  include DataMapper::Resource

  property :id,             Serial
  property :master_item_id, Integer # add this property if backlinks are desired
  
  property :name,           String
  property :description,    String
  
  is :cloneable
  
  # adds the following api to this class
  #
  # Item#clone_resource(nr_of_clones, attributes_to_clone = <:all|String|Array[String|Symbol]|ItemCloneSpec>)
  # Item#master_resource
  # Item#cloned_resources
  # Item#has_backlinks_to_master?
  # Item#has_clone_specs?
  
end

# will define and thus be able to auto_migrate! by using dm-is-remixable:
#
# class ItemCloneSpec
#
#   include DataMapper::Resource
#
#   property :name,                String, :length => (1..64)
#   property :description,         Text
#
#   property :attributes_to_clone, String, :length => (1..1024), :auto_validation => false
#
#   property :created_at,          DateTime
#   property :updated_at,          DateTime
#   property :deleted_at,          ParanoidDateTime
#
#   # allow an instance of self, an array of strings or symbols, or a comma separated list of attribute names as string
#   # storage format is a comma separated string with no whitespace
#   def attributes_to_clone=(attrs)
#     case attrs = (attrs.is_a?(self.class) ? attrs.attributes_to_clone : attrs)
#     when String then attribute_set(:attributes_to_clone, attrs.gsub(' ', ''))
#     when Symbol then attribute_set(:attributes_to_clone, attrs.to_s)
#     when Array  then attribute_set(:attributes_to_clone, attrs.map { |a| a.to_s }.join(','))
#     else
#       raise ArgumentError, "attrs must be an Array or a String separated by commas but was #{attrs.class.name}, #{attrs}"
#     end
#   end
#
#   # returns an array of symbols representing the properties to be cloned
#   def attributes_to_clone
#     (attrs = attribute_get(:attributes_to_clone)) ? attrs.split(',').map { |a| a.to_sym } : []
#   end
#
# end