Module: UssdEngine::Controller::Storable::StorableClassMethods

Defined in:
lib/ussd_engine/controller/storable.rb

Instance Method Summary collapse

Instance Method Details

#stores(field, accessor = nil, &block) ⇒ Object 



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# File 'lib/ussd_engine/controller/storable.rb', line 13

def stores(field, accessor = nil, &block)
  # Given
  # field = :user_id
  instance_prop = "@#{field}" # @user_id
  key_method_name = "#{field}_key" # user_id_key
  getter_method_name = field  # user_id
  setter_method_name = "#{field}="  # user_id=

  # def user_id_key
  #   File.join ussd_request_id, "user_id"
  # end
  define_method key_method_name do
    File.join ussd_request_id, field.to_s
  end

  # def user_id
  #   session[user_id_key]
  # end
  define_method getter_method_name do
    session[send(key_method_name)]
  end

  # def user_id=(value)
  #   session[user_id_key] = value
  # end
  define_method setter_method_name do |value|
    session[send(key_method_name)] = value
  end

  if accessor.present?
    raise "A block is required if you pass an accessor" unless block_given?

    # Given
    # accessor = :user
    cache_method_name = "#{accessor}_cache" # user_cache
    cache_instance_prop = "@#{cache_method_name}" # @user_cache

    # def user_cache
    #   @user_cache ||= {}
    # end
    define_method cache_method_name do
      unless instance_variable_defined? cache_instance_prop
        instance_variable_set cache_instance_prop, {}
      end
      instance_variable_get cache_instance_prop
    end

    # Given
    # block = do |user_id|
    #   User.find user_id
    # end
    #
    # def user
    #   return if user_id.blank?
    #
    #   user_cache[user_id] ||= block(user_id)
    # end
    define_method accessor do
      field_value = send(getter_method_name)
      return if field_value.blank?

      send(cache_method_name)[field_value] ||= instance_exec(field_value, &block)
    end
  end
end