has_inherited

Easily share variables between Rails models with inheritance.

Installation

➜  ~  gem install has_inherited

Using has_inheritable

(NOTE: has_inherited 2.x or greater only works with Rails 3. If you need Rails 2.x support please use has_inherited 1.0) The intention of this library is to make it easy to inherit particular variables between models in rails apps. We start with a parent model that will function as a pseudo-polymorphic association for children objects.

1. Define a parent object

class Seo < ActiveRecord::Base
  is_inheritable
end

Use the following as a migration guideline. Note: The table structure is important.

create_table :seos do |t|
  t.integer :inheritable_id
  t.string  :inheritable_type
  t.string  :name, :limit => 50, :null => false
  t.string  :value
  t.string  :value_type
end

2. Define child objects.

class Industry < ActiveRecord::Base
  has_inherited :seo, :from => Seo
  has_many :clients
end

This gives industry instances access to the seo namespace from the Seo object. In this case it will end up being ‘industry.seo.X`

class Client < ActiveRecord::Base
  belongs_to :industry
  has_many :stores
  has_inherited :seo, :from => [:industry, :seo], :inherit_class => 'Seo'
end

This gives client instances access to the seo namespace from its associated industry. You also have to specify the ‘:inherit_class` so we know what table to look up.

Examples

#Set the SEO global title
#Seo.global.title = "SEO Title"

#Grab that child industry title
industry.seo.title
# => 'SEO Title'

#Grab the client title
client.seo.title
# => 'SEO Title'

#Change the industry title
industry.seo.title = 'Industry Title'

#Check the client
client.seo.title
# => 'Industry Title'

#Grab all the Keys for the client
client.seo.all
# => {:title=>"Industry Title"}

#Grab all the non-inherited keys from the client
client.seo.all(false)
# => {}

Note on Patches/Pull Requests

Fork the project.
Make your feature addition or bug fix.
Add tests for it. This is important so I don’t break it in a future version unintentionally.
Commit, do not mess with rakefile, version, or history. (if you want to have your own version, that is fine but bump version in a commit by itself I can ignore when I pull)
Send me a pull request. Bonus points for topic branches.