Call Me Back

Synopsis

Automatically provide dead-simple ActiveSupport callbacks to your instance methods.

Preface

This gem is a small extension of ActiveSupport available features. In fact, as referred at this this link, creating callbacks for custom methods induces modify your existent method code source. This gem just automates this task.

Why?

When I work in Ruby On Rails projects, I often use native callbacks, provided by ActiveSupport, such as before_save or after_create. But sometimes I want to use this kind of hook methods for my methods. Of course, there is a way to perform this, explained in the previous link. This gem just simplifies the way you can do this.

Installation

Just type:

gem install callmeback

Or add it to your gem file:

gem 'callmeback'

Usage

Add include Callmeback after all your module inclusions to be sure the gem works.

class Example
  include Mongoid::Document
  include Callmeback

  before :foo => :bar

  def foo
    (@result ||= []) << 'foo'
  end

  def bar
    (@result ||= []) << 'bar'
  end
end

example = Example.new
example.foo #=> ['bar','foo']

Because this extension overrides the .initialize method, if you need to redefine it, please add callback_binding to your .initialize method. Here is the same example as above but implemeting the .initialize method:

class Example
  include Mongoid::Document
  include Callmeback

  after :foo => :bar

  def initialize
    @result = []
    callback_binding
  end

  def foo
    @result << 'foo'
  end

  def bar
    @result << 'bar'
  end
end

example = Example.new
example.foo #=> ['foo','bar']

You can use before, after and around, as if you use the suggested method in the ActiveSupport::Callbacks documentation.

Note that Mongoid is used in these examples but it should also work with ActiveRecord.

How is it work?

First, this gem module defines the class methods .before, .after, .around in your class. Then when you instanciate your class, the gem overrides your binded methods and wraps them to bind your custom callbacks.

Contributing to callmeback

Check out the latest master to make sure the feature hasn’t been implemented or the bug hasn’t been fixed yet.
Check out the issue tracker to make sure someone already hasn’t requested it and/or contributed it.
Fork the project.
Start a feature/bugfix branch.
Commit and push until you are happy with your contribution.
Make sure to add tests for it. This is important so I don’t break it in a future version unintentionally.
Please try not to mess with the Rakefile, version, or history. If you want to have your own version, or is otherwise necessary, that is fine, but please isolate to its own commit so I can cherry-pick around it.