It's Time to Repay Your Debt

It’s Time to Repay Your Debt
Windy City Rails

September 11, 2010

Key Points

✤ Releasing Gems is ridiculously easy!

✤ You don’t have to be Matz!

✤ If you’ve ever DRYed your codebase, you’re probably ready

Before Hook

✤ before_filter :filter_method

✤ before_filter :filter_method, :only => [:foo, :bar]

✤ before_filter :filter_method, :except => :baz

class Foo
  include Filters

  before_filter :before_method
  after_filter :after_method, :only => :bar

  def foo(x)
    puts "foo #{x}"
  end

  def bar
    puts "bar"
  end

  def before_method
    puts "before_method" and return true
  end

  def after_method
    puts "after_method" and return true
  end

end

module Filters
  class << self
    def included(mod)
      mod.extend(Filters::ClassMethods)
      mod.instance_methods(false).each do |method|
        mod.add_global_hook(method)
      end
    end
  end

  module ClassMethods
    # Real methods
  end
end

befo
re_ﬁlte
r :me
# op thod
tions , :onl
[:onl
y] => y => :foo
[:foo
module ClassMethods ]
def before_filter(hook_method,options={})
options.keys.each{|k|options[k] = [options[k]].flatten}
   (@@before_hooks||={})[hook_method.to_sym] = options
end

def after_filter(hook_method,options={})
   options.keys.each{|k|options[k] = [options[k]].flatten}
   (@@after_hooks||={})[hook_method.to_sym] = options
end

end
> [:foo]
ethod, : except =
afte r_ ﬁlter :m > [:foo]
[:only] =
# options

Hook Tactics

✤ Alias the original method :foo => :__foo

✤ Rewrite :foo

✤ Run any before_hooks

✤ Run the original method (if the before_hooks returned true)

✤ Run any after_hooks

def add_global_hook(method)
  alias_method "__#{method}", method
  define_method method do |*args,&block|
    @@before_hooks ||= {}
    @@after_hooks ||= {}
    @@before_hooks.keys.each do |hook|
      unless (@@before_hooks[hook][:except]||[]).include?(method) ||
(@@before_hooks[hook][:only] &&
!@@before_hooks[hook][:only].include?(method))
        return unless send(hook)
      end
    end unless @@before_hooks[method] || @@after_hooks[method]

    returnable = send("__#{method}",*args,&block)

    @@after_hooks.keys.each do |hook|
      unless (@@after_hooks[hook][:except]||[]).include?(method) ||
(@@after_hooks[hook][:only] &&
!@@after_hooks[hook][:only].include?(method))
        return unless send(hook)
      end
    end unless @@before_hooks[method] || @@after_hooks[method]
return returnable
  end
end

module Filters
  class << self
    def included(mod)
      mod.extend(Filters::ClassMethods)
      mod.instance_methods(false).each do |method|
        mod.add_global_hook(method)
      end
    end
  end

  module ClassMethods
    # ...
def method_added(method)
  add_global_hook(method) unless
method.to_s[0,2] == "__" ||
instance_methods.include?("__#{method}".to_sym)
end
  end
end

Let’s Make It A Gem!

ﬁlt.gemspec
Gem::Specification.new do |s|
  s.name = "filt"
  s.version = "0.0.1"
  s.summary = "before and after filters for Ruby"
s.files = ["lib/filt"]
end

Let’s Share The Gem!

✤ gem build filt.gemspec

✤ gem push filt-0.0.1.gem

✤ http://rubygems.org/gems/filt

John Doe Programmer

✤ Windows 7 machine (moderate hardware)

✤ Visual Studio

✤ Microsoft SQL Server

✤ A little bit of PHP

✤ Minimal web experience

This Isn’t Bad!

✤ Choice is important!

✤ There are many “right ways”

✤ Flexibility allows us to create better solutions

OpenPGP

module OpenPGP
  class Message
    include Enumerable

    # ...

    def self.decrypt(data, options = {}, &block)
      raise NotImplementedError # TODO
    end
end
end

What Is A Product?

✤ Utility

✤ Aesthetics

Aesthetics
map.resources :products, :member => {:short
=> :post}, :collection => {:long => :get} do |products|
  products.resource :category
end
resources :products do
  resource :category

  member do
    post :short
  end

  collection do
    get :long
  end
end

match "/posts/github" => redirect("http://github.com/rails.atom")

Utility

✤ Solves a problem

Agile (according to rumor)

✤ Do the absolute bare minimum to get something delivered

Agile

✤ Do the absolute bare minimum to get something delivered*

Delivered, n.

✤ Coded

✤ Deployed

✤ Supported

✤ Tested

✤ Extensible

✤ Usable by the client

The Lazy Programmer’s Manifesto

✤ I want to write code once

✤ I want to be able to read code without having to refer to external docs

✤ I want to be able to rely on other libraries

✤ I want to use adaptable solutions for numerous problems

✤ I want to always be working on something new

Idea Filtering

✤ To share

✤ Business value

✤ Practical use

✤ To learn

✤ No requirements!

✤ Don’t post it publicly!

Testing

✤ We all say we do it!

✤ RSpec and Cucumber are both easy to set up for gems

✤ Design veriﬁcation tool

Extensible

✤ Write clean code (don’t post a spike)

✤ Have a peer review your stuff

✤ Follow the Unix philosophy: do one thing really well

✤ Leverage other gems!

Documented

✤ Who’s looking at your code if it’s on GitHub, RubyGems?

✤ RDoc, YARD, etc

✤ Getting Started

✤ Blog posts!

Supported

✤ Put your name on it

✤ Answer your emails, damnit

✤ Accept patches (at minimum)

Be Honest

✤ Don’t be too proud to hand over the reins

✤ If your project is worth supporting, someone will step up

✤ Be a net-positive for the community

✤ Don’t announce things if they’re not done

But, But, But!!!

✤ Don’t post it

✤ Post it in a limited venue

✤ Put a disclaimer on your project

How Does The Internet Filter
Stupid?

✤ It doesn’t?

✤ Making tasks difﬁcult

✤ Having enough eyes

Matz Wisdom

✤ “Ruby treats you like a grown-up programmer”

What Happens When Grown-Ups
Have Too Much Fun?

How To Be A Good Parent

✤ Don’t create sensory overload

✤ Spoon-feed sometimes

✤ Remember you’re used to the
status quo

✤ Be a mentor

✤ Provide solutions to problems,
not blocks of code

It’s Time To Repay Your Debt

Thank You!

✤ Kevin W. Gisi

✤ Twitter: @gisikw

✤ http://spkr8.com/t/4414

It's Time to Repay Your Debt

Empfohlen

Empfohlen

Weitere ähnliche Inhalte

Kürzlich hochgeladen

Kürzlich hochgeladen (20)

Empfohlen

Empfohlen (20)

It's Time to Repay Your Debt