Castkit::ActiveRecord is a companion gem to Castkit that bridges your Castkit::DataObject classes with ActiveRecord models. It enables conversion to/from models, assignment, and safe update flows for nested objects.

bundle add castkit-activerecord

Include the module in your Castkit::DataObject class and associate it with a model:

class UserDto < Castkit::DataObject
  include Castkit::ActiveRecord
  model User

  string :name
  has_many :posts, of: PostDto
end

user_dto = UserDto.from_model(User.find(1))

user_model = user_dto.to_model

user.update_from_dataobject(user_dto, mode: :merge)

Use update_from_dataobject! if you want to raise on failure. Pass ignore: [:field] to skip certain fields.

Nested dataobject and has_many/has_one relationships are supported:

class PostDto < Castkit::DataObject
  include Castkit::ActiveRecord
  model Post

  string :title
  dataobject :author, UserDto
end

You can skip certain fields from being assigned during updates:

# This is automatically included
class User < ApplicationRecord

  castkit_ignored_on_update :id, :status
end

• :replace — full object replacement (default)
• :merge — performs recursive merging via update_from_dataobject! on nested models

• to_model → Instantiates a model from the DTO

• to_dataobject(UserDto)
• update_from_dataobject(dto, mode: :replace, ignore: [])
• update_from_dataobject!(dto, mode: :replace, ignore: [])

MIT. See LICENSE.

Created with ❤️ by Nathan Lucas