Using Representable to convert one hash to another hash without having to create intermediate classes

example.rb

require 'representable'
require 'representable/json'
require 'ostruct'
require 'json'
require 'hashie'

json = {
  person: {
    name: 'Beth',
    surname: 'Someone'
  },
  address: {
    address_line_1: '999 Some Street'
  }
}.to_json

class Representor < Representable::Decorator
  include Representable::JSON

  property :person, class: Hashie::Mash  do
    property :firstname, as: :name
    property :lastname, as: :surname
  end
  property :address, class: Hashie::Mash do
    property :street, as: :address_line_1
  end
end

target = Hashie::Mash.new
Representor.new(target).from_json(json)
puts target.to_hash
# => {"person"=>{"firstname"=>"Beth", "lastname"=>"Someone"}, "address"=>{"street"=>"999 Some Street"}}

Using OpenStruct instead of Hashie::Mash gives you

{:person=>#<OpenStruct firstname="Beth", lastname="Skurrie">, 
 :address=>#<OpenStruct street="999 Some Street">}

Bethtest comment.