CallbackAction

This gem gives you ability to add callbacks like validate / before_action / before_fitler etc to your Active Record models and plain ruby classes.

Installation

Add this line to your application's Gemfile:

gem 'callback_action'

And then execute:

$ bundle

Or install it yourself as:

$ gem install callback_action

Preliminary

• Ruby >= 2.1.0
• Rails >= 4.2.6

Usage

1. validate

In Rails

This gem adds a before option to the validate method. Use it on any of your model's method. Simply add custom validation method just like you usually do.

• It runs the method if validation is good
• Otherwise, it returns false (if there is any error)

class Car < ActiveRecord::Base
  validate :key_present, before: [:unlock_door]

  def unlock_door
    # unlock the door
  end

  private

  def key_present
    unless has_key? && valid_key?
      errors.add(:base, 'need the right key')
    end
  end
end

car = Car.new
car.unlock_door
# If has_key?
#   - do whatever the method does
#   - return whatever it returns
# If !has_key?
#   - returns false
#   - car.errors.full_messages => ['need the right key']

At the same time, it preserves the default validate logic if before option is not used.

class Car < ActiveRecord::Base
  validate :valid_vin_number
end

In Plain Ruby

This gem adds a validate method to classes that extend this module. You should raise error in the validator method

• It execute the method if validation passes.
• It raises the error you specify in the validator method, and stop there.

class Car
  extend ActionCallback
  validate :key_present, before: [:unlock_door]

  def unlock_door
    # unlock the door
  end

  private

  def key_present
    fail 'key invalid' unless valid_key?
  end
end

2. before_action / after_action

If you are using Rails, in your Active Record models:

class Foobar < ActiveRecord::Base
  before_action :foobar, on: [:foo, :bar]
  
  def foo
    # ...
  end

  def bar
    # ...
  end

  def foobar
    # ...
  end
end

If you are using plain ruby:

class Foobar
  extend ActionCallback

  before_action :foobar, on: [:foo, :bar]
  
  def foo
    # ...
  end

  def bar
    # ...
  end

  def foobar
    # ...
  end
end

Available callbacks

Currently, you can use before_action, after_action to define callbacks.

before_action / before_filter

This will give you a before callback.

before_action :before_callback, on: [:methods_that_will_invoke_before_callbacks]

after_action / after_action

This will give you a after callback.

after_action :after_callback, on: [:methods_that_will_invoke_after_callbacks]

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/edmundleex/callback_action. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

License

The gem is available as open source under the terms of the MIT License.