has_states

Add ActiveRecord integrated state machine functionality.

WHY?

acts_as_state_machine and AASM didn't feel quite right to me.

Validations and guards were redundant, transitions were not observable and direct manipulation of state attributes did not result in transitions.

This is an attempt to make it work (the way I thought it should).

Example

# models/user.rb
class User < ActiveRecord::Base
  has_states :signed_up, :unverified, :verified, :disabled do
    on :invite do
      transition :signed_up => :unverified
    end
    on :verify do
      transition :unverified => :verified
    end
    on :disabled do
      transition :verified => :disabled
    end
    on :enable do
      transition :disabled => :verified
    end
  end

  before_enter_unverified :set_verification_key
  
  ...
end

# models/user_observer.rb
class UserObserver < ActiveRecord::Observer
  def after_enter_signed_up(user)
    UserMailer.deliver_signup_notification(user)
  end

  def after_enter_unverified(user)
    UserMailer.deliver_invitation(user)
  end

  def after_enter_verified(user)
    UserMailer.deliver_welcome(user)
  end
end

Installation

$ script/plugin install git://github.com/sbfaulkner/has_states.git

Legal

Author: S. Brent Faulkner brentf@unwwwired.net
License: Copyright © 2008 unwwwired.net, released under the MIT license