mongoid hash extension

mongoid_hash_support.rb

# BSON stores document keys as strings, so Hash keys are strings
# when going into MongoDB and coming out. This extension allows
# a developer to not worry as to whether or not the keys are
# Strings or Symbols.
#
# This requires Mongoid 2.4.3+ and Rails 3.
#
# Instead of needing Rails you could just require ActiveSupport. In your Gemfile (or .gemspec)
# gem "activesupport", ">= 3.0.0"
#
# In your code:
#   require 'active_support/hash_with_indifferent_access'
#
module MongoidHashSupport
  def self.included(klass)
    klass.class_eval do
      # @override Mongoid::Field
      def self.field(name, options={})
        field = super

        if options.fetch(:type, nil) == Hash
          getter_name = name.is_a?(Symbol) ? name : name.intern
          setter_name = "#{getter_name}=".intern

          define_method(getter_name) do
            val = super
            unless val.nil? || val.is_a?(HashWithIndifferentAccess)
              wrapped_hash = val.with_indifferent_access
              self.send(setter_name, wrapped_hash)
              val = wrapped_hash
            end
            val
          end

          define_method(setter_name) do |hash|
            unless hash.nil? || hash.is_a?(HashWithIndifferentAccess)
              hash = hash.with_indifferent_access
            end
            super(hash)
          end
        end
        field
      end
    end
  end
end