Usage

Methods you should be using

Although Aspekt consists of 4 classes and 2 modules, you should be using directly only 3 methods which API will never change:

• #before (Aspekt::Helpers::ShorthandMethods#before)
• #after (Aspekt::Helpers::ShorthandMethods#after)
• #around (Aspekt::Helpers::ShorthandMethods#around)

before|after|around ([instance(s)|type(s): Symbol|Regexp|Object|Array<Symbol|Regexp|Object>],) method(s): Symbol|Regexp|Array<Symbol|Regexp> do |joinpoint|
  # what to do ...
  # in case of around, `joinpoint.proceed` has to be called
end

• If instance or type is not specified, type: self is assumed.
• If you want, you can overwrite them and use them in your application as you want... Or you just create around advice for them and change arguments order as you like.

Example #1: In class body

class Example
  def one; end
  def two; end
  def self.three; end
  def self.four; end

  before method: :one do 
    puts "before method one"
  end

  after({type: self, methods: [:one, :two]}, {instance: self, method: :three}) do |joinpoint|
    puts "method #{joinpoint[:method]} was called on #{self} with arguments #{joinpoint[:args]}"
  end 

  around instance: self, method: /thr/ do |joinpoint|
    puts "Before around #{joinpoint}"
    result = joinpoint.proceed           # calling orginal method
    puts "After around #{joinpoint}"
    result                               # return orginal value
  end

  class<<self
    before method: :four do 
      puts "before four"
    end
  end

end

Example #2: In random place

before types: [/Strin/, /Arra/], instances: [some_object, :SomeClassForSingletonMethods], methods: [/^beginning_with/, :to_mushroom] do |joinpoint|
  puts joinpoint
end

Example #3: In aspects

Recommended

1. Create folder called 'aspects' in your load path.
2. Create Aspect for Concern:

# ./aspects/logging/exceptions.rb (parent folder of 'aspects' must be in load path):
module Aspects
  module Logging
    module Exceptions

      after type: Exception, method: :initialize do |joinpoint|
        MyLogger.log "Just threw exception #{self.class}: #{self.backtrace}"
      end

    end
  end
end

You could also

• Create your own logic, but you should take care, that aspects are loaded.

Installation

Using Bundler

Add to your Gemfile:

gem 'aspekt'

And run:

bundle install

Using gem

gem install aspekt