Dynamic Fields using mongoid. Use Mongoid to store a random size hash.

console_usage.rb

hsh = {}; (0..rand(5)).each { |idx| hsh["val#{idx}"] = [rand(5),rand(5),(idx % 2 == 0) ? hsh.clone: rand(5)] * (rand(2)+1) }; hsh
my_taco = TacoHash.new
my_taco.write_attributes(hsh)
my_taco.save
my_new_taco = TacoHash.last
#<TacoHash _id: 4e6a5a031a2c840d83000002, val0: [2, 0, {}, 2, 0, {}], val1: [2, 1, 2], val2: [1, 4, {"val0"=>[2, 0, {}, 2, 0, {}], "val1"=>[2, 1, 2]}], val3: [1, 1, 1, 1, 1, 1], val4: [4, 2, {"val0"=>[2, 0, {}, 2, 0, {}], "val1"=>[2, 1, 2], "val2"=>[1, 4, {"val0"=>[2, 0, {}, 2, 0, {}], "val1"=>[2, 1, 2]}], "val3"=>[1, 1, 1, 1, 1, 1]}, 4, 2, {"val0"=>[2, 0, {}, 2, 0, {}], "val1"=>[2, 1, 2], "val2"=>[1, 4, {"val0"=>[2, 0, {}, 2, 0, {}], "val1"=>[2, 1, 2]}], "val3"=>[1, 1, 1, 1, 1, 1]}]>
my_new_taco.val0

mongoid.rb

require 'mongoid'
# MongoDB ENV vars
 # export MONGOID_HOST='localhost'
 # export MONGOID_PORT='27017'
 # export MONGOID_USERNAME='billy'
 # export MONGOID_PASSWORD='iambilly'
 # export MONGOID_DATABASE='billys_db'
 
  File.open(File.join(RAILS_ROOT, 'config/mongodb.yml'), 'r') do |f|
  @settings = YAML.load(f)[RAILS_ENV]
  end
  port = @settings["port"].nil? ? Mongo::Connection::DEFAULT_PORT : @settings["port"]

  connection = Mongo::Connection.new(@settings["host"], port )
  Mongoid.database = connection.db(@settings["database"])
  Mongoid.configure do |config|
  	  config.allow_dynamic_fields = true
  end

taco_hash.rb

class TacoHash  
  include Mongoid::Document
  field	:tacos, :type => Hash
end