Is there a way to serialize ActiveRecord's JSON properties using HashWithIndifferentAccess?

| You can use a custom serializer so you can access the JSON object with symbols as well.

# app/models/user.rb
class User < ActiveRecord::Base
  serialize :preferences, HashSerializer
end

# app/serializers/hash_serializer.rb
class HashSerializer
  def self.dump(hash)
    hash
  end

  def self.load(hash)
    (hash || {}).with_indifferent_access
  end
end

Full credit - sans googling - goes to http://nandovieira.com/using-postgresql-and-jsonb-with-ruby-on-rails.

If your root object is an array you need to handle it slightly differently.

Rails 5+

class User < ActiveRecord::Base
  serialize :preferences, HashSerializer
  serialize :some_list, ArrayHashSerializer
end

class HashSerializer
  def self.dump(hash)
    hash
  end

  def self.load(hash)
    (hash || {}).with_indifferent_access
  end
end

class ArrayHashSerializer
  def self.dump(array)
    array
  end

  def self.load(array)
    (array || []).map(&:with_indifferent_access)
  end
end

Rails <= 4

class User < ActiveRecord::Base
  serialize :preferences, HashSerializer
  serialize :some_list, ArrayHashSerializer
end

class HashSerializer
  def self.dump(hash)
    hash.to_json
  end

  def self.load(hash)
    (hash || {}).with_indifferent_access
  end
end

class ArrayHashSerializer
  def self.dump(array)
    array.to_json
  end

  def self.load(array)
    (array || []).map(&:with_indifferent_access)
  end
end