Using Cocoa’s KVC to assign JSON keys and values to Rubymotion models <Objects>

values_for_keys_with_dictionary.rb

class User
  MAPPING_KEYS = Hash[ 'user_name', :name, 'total_video_count', :videosCount]
  attr_accessor *MAPPING_KEYS.values, :age

  def initialize(args={})
    if args.is_a?(Hash)
      dictionary = Hash[ args.map { |k, v| [MAPPING_KEYS.fetch(k, k) , v] } ]
      setValuesForKeysWithDictionary(dictionary)
    end
  end
    
  def setValue(value, forUndefinedKey:key); end
end

class Video
  MAPPING_KEYS = Hash[
    'video_title', :title,
    'video_views_total', :viewCount,
    'video_author', :uploader
  ]
  attr_accessor(*MAPPING_KEYS.values)

  def initialize(args={})
    if args.is_a?(Hash)
      dictionary = Hash[ args.map { |k, v| [ MAPPING_KEYS.fetch(k, k), v ]} ]
      dictionary.update({:uploader => ''}) { |_, oldval, _| User.new(oldval) }
      setValuesForKeysWithDictionary(dictionary)
    end
  end

  def setValue(value, forUndefinedKey:key); end
end


objects = [
  {
    video_title: 'The awesomeness of being',
    video_views_total: 23,
    video_author: {
      user_name: "t_mueller",
      age: 34,
      total_video_count: 100,
    }
  },
  {
    video_title: 'The awesomeness of being 1',
    video_views_total: 2,
    video_author: {
      user_name: "johndoe",
      age: 17,
      total_video_count: 23,
    }
  },
  {
    video_title: 'Blubbb 34',
    video_views_total: 1000,
    video_author: {
      user_name: "Jackson5",
      age: 34,
      total_video_count: 100,
    }
  },
]

## Lets check that thing...
error = nil
data = NSJSONSerialization.dataWithJSONObject(objects, options:NSJSONWritingPrettyPrinted, error:error)
jsonObject = NSJSONSerialization.JSONObjectWithData(data, options:NSJSONReadingMutableContainers, error:error)
NSLog('ERROR') if error

videos = jsonObject.map { |hash| Video.new(hash) }
NSLog("%@", videos.map(&:inspect))

#2014-03-12 10:40:55.154 macruby[1849:d07] (
#  "#<Video:0x400d25fa0 @title=\"The awesomeness of being\" @viewCount=23 @uploader=#<User:0x400d26380 @name=\"t_mueller\" @age=34 @videosCount=100>>",
#  "#<Video:0x40040ca40 @viewCount=2 @uploader=#<User:0x400d279c0 @name=\"johndoe\" @age=17 @videosCount=23> @title=\"The awesomeness of being 1\">",
#  "#<Video:0x400d28540 @viewCount=1000 @uploader=#<User:0x400d28460 @name=\"Jackson5\" @age=34 @videosCount=100> @title=\"Blubbb 34\">"
#)