Rails 3: How to create a new nested resource?

Question

The Getting Started Rails Guide kind of glosses over this part since it doesn\'t implement the \"new\" action of the Comments controller. In my application, I have a book mo

Answer 1

Perhaps unrelated, but from this question's title you might arrive here looking for how to do something slightly different.

Lets say you want to do Book.new(name: 'FooBar', author: 'SO') and you want to split some metadata into a separate model, called readable_config which is polymorphic and stores name and author for multiple models.

How do you accept Book.new(name: 'FooBar', author: 'SO') to build the Book model and also the readable_config model (which I would, perhaps mistakenly, call a 'nested resource')

This can be done as so:

class Book < ActiveRecord::Base
  has_one :readable_config, dependent: :destroy, autosave: true, validate: true
  delegate: :name, :name=, :author, :author=, :to => :readable_config

  def readable_config
    super ? super : build_readable_config
  end
end