EasyDecorator

EasyDecorator is a module that bring's in a Python-like method decorator pattern into Ruby.

Table of Contents

• Installation
• Usage
  • Include Module
  • Define Decorator
  • Decorating Methods
  • Example
• Contributing

Installation

command line

$ gem install easy_decorator

Gemfile

# ./Gemfile

source 'https://rubygems.org`
# ...
gem 'easy_decorator', '~> 0.2.0'

Usage

Include Module

# ./my_class.rb
class MyClass
  include EasyDecorator
end

Define Decorator

A decorator should be defined as a method with an inner wrapper. Within the wrapper you can call the passed method via func.call(*args).

def my_decorator(func, *args)
  wrapper do 
    # code here
    func.call(*args)
    # code here
  end
end

* wrapper is essentially syntactic sugar for a proc.

Decorating Methods

decorate(:my_method, :my_decorator)
def my_method(a, b)
  # code here
end

You can apply multiple decorators to a method, which will applies from last to first declared.

decorate(:my_method, :outer_decorator)
decorate(:my_method, :inner_decorator)
def my_method(*args)
  # ...
end

# is essentially the same as:
outer_decorator(inner_decorator(public_method(:my_method))).call(*args)

Example

# ./calculator.rb

class Calculator
  # include module
  include EasyDecorator

  # define decorator
  def calculate_time(func, *args)
    wrap do
      logger.info("Timing #{method_name}...")
      start_time = Time.now
      # call inner method
      result = func.call(*args)
      end_time = Time.now
      logger.info("Processing Time: #{end_time - start_time}")

      result
    end
  end

  # decorate method
  decorate(:add_numbers, :calculate_time)
  def add_numbers(a, b)
    return a + b
  end
end

Result:

$ Calculator.new.add_numbers(1,2)
Timing add_numbers...
Processing Time: 0.0001572930
=> 3

Contributing

1. Fork the repo
2. Create a your feature branch (git checkout -b my-feature-branch)
3. Update CHANGELOG.md with a bulleted list of your changes under the unreleased heading.
4. Include rspec tests for your changes
5. Commit your changes to your branch (git commit -am 'Added my feature')
6. Push to your remote forked repo (git push origin my-featuer-branch)
7. Create a new Pull Request Once I am able to review the pull request, I will either either approve and merge, or give feedback on it if I do not merge it. I will do my best to address Pull Requests as time allows.