spira-active_record_isomorphisms

Establish isomorphisms between your Spira and ActiveRecord models.

Installation

Add this line to your application's Gemfile:

gem 'spira-active_record_isomorphisms'

And then execute:

$ bundle

Or install it yourself as:

$ gem install spira-active_record_isomorphisms

Usage

Defining Isomorphisms

Isomorphisms are established by adding an isomorphic_with call to your Spira model declaration. For example, given an ActiveRecord User model:

class User < ActiveRecord::Base; end

with id, email and encrypted_password properties, an isomorphic Spira Person model can be defined:

class Person < Spira::Base
  configure base_uri: 'http://example.org/example/people',
            default_vocabulary: 'http://example.org/example/vocab'

  isomorphic_with :user
  property :name, predicate: FOAF.name, type: String
end

Associating Models

Models can be associated by setting the corresponding attributes:

> bob = Person.for('bob')
=> <Person:2202810640 @subject: http://example.org/example/people/bob>
> bob.user = User.find(1)
=> #<User id: 1, email: "bob@example.com", ...>
> bob.user
=> #<User id: 1, email: "bob@example.com", ...>
> bob.save
=> <Person:2202810640 @subject: http://example.org/example/people/bob>
> User.find(1).person
=> <Person:2202810640 @subject: http://example.org/example/people/bob>
> bob.user_id
=> 1

Note that:

• A default_vocabulary must be set on the Spira model.
• The Spira model must be saved before the reverse association can be accessed.
• The two classes must have different names.
• An id property is added to the Spira model corresponding to the name of the ActiveRecord model (in this case user_id).

Delegated Attributes

By default, attributes are delegated in both directions:

> bob = Person.for('bob')
=> <Person:2202810640 @subject: http://example.org/example/people/bob>
> bob.user = User.find(1)
=> #<User id: 1, email: "bob@example.com", ...>
> bob.email
=> "bob@example.com"
> bob.name = 'Bob'
=> "Bob"
> User.find(1).name
=> "Bob"

This can be disabled by setting delegation to false: isomorphic_with :user, delegation: false

Contributing

1. Fork it ( https://github.com/nhurden/spira-active\_record\_isomorphisms/fork )
2. Create your feature branch (git checkout -b feature/my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin feature/my-new-feature)
5. Create a new Pull Request