CustomAttributes

Introduction

CustomAttributes allows you to add custom attributes to ActiveRecord objects, optionally scoped by another model (e.g. users or accounts).

Installation

To install, simply run:

$ gem install custom_attributes

Or put this in your Gemfile:

gem 'custom_attributes'

To create the migration for the custom_attributes tables, run:

rails g custom_attributes:install

Usage

Define that a model has custom attributes:

class Contact < ActiveRecord::Base
  has_custom_attributes
end

Now, add custom attributes to the model:

Contact.add_custom_attribute :internal_id
Contact.add_custom_attribute "internal_id"
Contact.add_custom_attribute [:internal_id, :nickname]

Use the new custom attributes like normal ones:

c = Contact.new
c.internal_id = "ABC-123"
c.nickname = "Dude"
c.save

Add scope by defining which controller method returns it:

::CustomAttributes.scope_method = :current_user

Or set the scope object directly:

::CustomAttributes.scope = User.first

Or override the controller method that returns the scope:

class ApplicationController < ActionController::Base
  def custom_attribute_scope
    # scope determination
    if current_user.can?(:customize, resource)
      current_user
    end
  end
end

Inspiration

has-magic-columns: http://code.google.com/p/has-magic-columns/