JsonObjects.rb

json_objects.rb

class DataObject
  def self.from(json_data)
    new(json_data)
  end

  def new(json_data)
    @json_data = JSON.parse(json_data)
  end

  def as_json(_opts={})
    # this becomes the object as you want it to appear in json
    # you can really add anything here to format the object correctly
    {
      name: filename,
      data: more_data,
      total_price: a_custom_method_named_total_price,
      quantity: quantity,
      price: price
    }

    # alternative you could return the original json
    # return @json_data
  end

  def filename
    @json_data["filename"]
  end

  def more_data
    @json_data["some_other_attribute"]
  end

  def quantity
    # you can build in custom defaults here
    @json_data["quantity"] || 1
  end

  def price
    # you can also rescue parse errors and prevent them causing weird things
    # in the application
    @json_data["price"]
  rescue StandardError
    return 0
  end

  def a_custom_method_named_total_price
    # you can now build on response data and make it easily testable
    quantity.to_f * price.to_f
  end
end

# USAGE
my_data = get_json_data_from_somewhere
data = DataObject.from(my_data)

# easily access in ruby code
data.price
data.quantity

# convert quickly to json
#
data.to_json