serialize rails form to mongoid or json

serialize_mongoid_form.rb

require 'pp'

# this is what the rails POST form params look like
have = {
    "concert"=>"yanni",
    "description"=>"an epic soundscape about oceans and stuff",
    "set_list"=>{
        "0"=>{
            "set_list"=>"opener",
            "energy"=>"high",
            "video_wall"=>"mostly birds",
            "songs"=>{
                "0"=>"paths on water", "1"=>"dance with a stranger"
            }
        },
        "1"=>{
            "set_list"=>"encore",
            "energy"=>"low",
            "video_wall"=>"flying toasters",
            "songs"=>{
                "0"=>"farewell"
            }
        }
    }
}

want = {
    concert: "yanni",
    description: "an epic soundscape about oceans and stuff",
    set_list: [
        {
            set_list: "opener",
            energy: "high",
            video_wall: "mostly birds",
            songs: [ "paths on water", "dance with a stranger" ]
        },
        {
            set_list: "encore",
            energy: "low",
            video_wall: "flying toasters",
            songs: [ "farewell" ]
        }
    ]
}

# helper
def is_a_number?(string)
  string.to_s.match(/\A[+-]?\d+?(\.\d+)?\Z/) == nil ? false : true
end

# the magic method
def serialize_params(original, serialized={})
  if original.respond_to?(:keys)
    original.keys.each do |key|
      current_attribute = original[key]
      if current_attribute.respond_to?(:keys)
        if serialized[key.to_sym].nil?
          serialized[key.to_sym] = Array.new
        end
        current_attribute.each do |i|
          # form params have numbers as keys, if nested forms recurse
          if (is_a_number?(i[0]) && i[1].class != String)
            # recurse
            serialized[key.to_sym] << serialize_params(i[1])
          elsif i[1].class == String
            # handles arrays of forms (like codes)
            serialized[key.to_sym] << i[1]
          end
        end
      else
        # assign regular attribute
        serialized[key.to_sym] = current_attribute
      end
    end
    return serialized
  end
end

got = serialize_params(have)

# the test that would go into minitest
puts "does this work?: #{got == want}"