Ruby: Implement SerializableStruct

serializable_struct.rb

require 'json'

module SerializableStruct
  class Dummy
    def self.members
      @members
    end

    def initialize(*vals)
      vals.each_with_index do |val, idx|
        send("#{self.class.members[idx]}=", val)
      end
    end

    def to_h
      self.class.members.each_with_object({}) do |it, acc|
        val = send(it)
        acc[it] = val.is_a?(Dummy) ? val.to_h : val
      end
    end

    def to_json
      to_h.to_json
    end

    def hash
      to_h.hash
    end
  end

  def self.new(*members)
    Class.new(Dummy) do
      @members = members
      attr_accessor *members
      yield self if block_given?
    end
  end
end

Parent = SerializableStruct.new(:child1, :child2) do
  Child1 = SerializableStruct.new(:name, :surname)
  Child2 = SerializableStruct.new(:name, :nickname)
end

structure = Parent.new(
  Child1.new("test", "good"),
  Child2.new("haha", "hehe")
)

puts structure.to_json
# Outputs: {"child1":{"name":"test","surname":"good"},"child2":{"name":"haha","nickname":"hehe"}}