StateMachines ActiveModel Integration
The ActiveModel integration is useful for both standalone usage and for providing the base implementation for ORMs which implement the ActiveModel API. This integration adds support for validation errors and dirty attribute tracking.
Installation
Add this line to your application's Gemfile:
gem 'state_machines-activemodel'
And then execute:
$ bundle
Or install it yourself as:
$ gem install state_machines-activemodel
Dependencies
Active Model 5.1+
Usage
class Vehicle
include ActiveModel::Dirty
include ActiveModel::Validations
attr_accessor :state
define_attribute_methods [:state]
state_machine :initial => :parked do
before_transition :parked => any - :parked, :do => :put_on_seatbelt
after_transition any => :parked do |vehicle, transition|
vehicle.seatbelt = 'off'
end
around_transition :benchmark
event :ignite do
transition :parked => :idling
end
state :first_gear, :second_gear do
validates_presence_of :seatbelt_on
end
end
def put_on_seatbelt
...
end
def benchmark
...
yield
...
end
end
class VehicleObserver < ActiveModel::Observer
# Callback for :ignite event *before* the transition is performed
def before_ignite(vehicle, transition)
# log message
end
# Generic transition callback *after* the transition is performed
def after_transition(vehicle, transition)
Audit.log(vehicle, transition)
end
# Generic callback after the transition fails to perform
def after_failure_to_transition(vehicle, transition)
Audit.error(vehicle, transition)
end
end
Contributing
- Fork it ( https://github.com/state-machines/state_machines-activemodel/fork )
- Create your feature branch (
git checkout -b my-new-feature
) - Commit your changes (
git commit -am 'Add some feature'
) - Push to the branch (
git push origin my-new-feature
) - Create a new Pull Request