Tweet
Tweet

Slide 1

Slide 1 text

Writing Your Own Ruby DSL March/2015

Slide 2

Slide 2 text

Ricardo Nacif

Slide 3

Slide 3 text

Automation QA Engineer at Avenue Code

Slide 4

Slide 4 text

Rails Developer

Slide 5

Slide 5 text

Bad time with Developers

Slide 6

Slide 6 text

No content

Slide 7

Slide 7 text

No content

Slide 8

Slide 8 text

No content

Slide 9

Slide 9 text

No content

Slide 10

Slide 10 text

No content

Slide 11

Slide 11 text

No content

Slide 12

Slide 12 text

Mineirês

Slide 13

Slide 13 text

UAI

Slide 14

Slide 14 text

No content

Slide 15

Slide 15 text

Po pô pó?

Slide 16

Slide 16 text

Pó pô

Slide 17

Slide 17 text

Oncetá?

Slide 18

Slide 18 text

Cadiquê?

Slide 19

Slide 19 text

Nó!

Slide 20

Slide 20 text

Nossa Senhora de Perpétuo Socorro

Slide 21

Slide 21 text

DSL

Slide 22

Slide 22 text

Domain-Specific Language

Slide 23

Slide 23 text

Linguagem de programação focada em um domínio/tarefa específico

Slide 24

Slide 24 text

DSL vs GPL

Slide 25

Slide 25 text

Remove código desnecessário ao realizar uma tarefa

Slide 26

Slide 26 text

Aumenta legibilidade

Slide 27

Slide 27 text

driver = Selenium::WebDriver.for :chrome driver.navigate.to "google.com" input = driver.find_element(:name, 'q') input.send_keys('ruby') button = driver.find_element(:name, 'lst-ib') button.click #capybara visit 'google.com' fill_in 'Search', with: 'ruby' click_button 'Google Search'

Slide 28

Slide 28 text

driver = Selenium::WebDriver.for :chrome driver.navigate.to "google.com" input = driver.find_element(:name, 'q') input.send_keys('ruby') button = driver.find_element(:name, 'lst-ib') button.click #capybara visit 'google.com' fill_in 'Search', with: 'ruby' click_button 'Google Search'

Slide 29

Slide 29 text

External Internal

Slide 30

Slide 30 text

External

Slide 31

Slide 31 text

HTML

Slide 32

Slide 32 text

CSS html, body { width: 100%; height: 100%; overflow: hidden; }

Slide 33

Slide 33 text

Gherkin (Cucumber) Feature: Serve coffee Coffee should not be served until paid for Coffee should not be served until the button has been pressed If there is no coffee left then money should be refunded Scenario: Buy last coffee Given there are 1 coffees left in the machine And I have deposited 1$ When I press the coffee button Then I should be served a coffee

Slide 34

Slide 34 text

Internal

Slide 35

Slide 35 text

RSpec # these two expectations... expect(alphabet).to start_with("a") expect(alphabet).to end_with("z") # ...can be combined into one expression: expect(alphabet).to start_with("a").and end_with( "z")

Slide 36

Slide 36 text

Factory Girl FactoryGirl.define do factory :user do first_name "John" last_name "Doe" admin false end factory :admin, class: User do first_name "Admin" last_name "User" admin true end end

Slide 37

Slide 37 text

Writing your own Ruby DSL

Slide 38

Slide 38 text

yield struct instance_eval self procs send lambda class method_missing blocks

Slide 39

Slide 39 text

Pizza Cookbook DSL

Slide 40

Slide 40 text

Quit the bullshit, let’s code!

Slide 41

Slide 41 text

new_pizza 'Frango Catupiry' do add_vegetable 'tomatoes' add_sauce 'barbecue' add_cheese 'catupiry' add_topping 'chicken' end

Slide 42

Slide 42 text

new_pizza('Frango Catupiry’) do add_vegetable(‘tomatoes') add_sauce('barbecue') add_cheese('catupiry') add_topping(‘chicken') end

Slide 43

Slide 43 text

block yield struct

Slide 44

Slide 44 text

block [1, 2, 3].each do |n| puts n end #=> 1 #=> 2 #=> 3

Slide 45

Slide 45 text

yield def execute_this_code yield end execute_this_code { puts 'Hey guys!' } #=> Hey guys!

Slide 46

Slide 46 text

class User attr_accessor :name, :age def initialize name, age @name = name @age = age end end User = Struct.new(:name, :age) struct

Slide 47

Slide 47 text

new_pizza 'Frango Catupiry' do add_vegetable 'tomatoes' add_sauce 'barbecue' add_cheese 'catupiry' add_topping 'chicken' end

Slide 48

Slide 48 text

Pizza = Struct.new(:name, :vegetable, :cheese, :sauce, :topping) def add_vegetable name @pizza.vegetable = name end #def add_sauce, add_cheese... def create_pizza name @pizza = Pizza.new(name) yield if block_given? end new_pizza 'Frango Catupiry' do add_vegetable 'tomatoes' add_sauce 'barbecue' add_cheese 'catupiry' add_topping 'chicken' end

Slide 49

Slide 49 text

Pizza = Struct.new(:name, :vegetable, :cheese, :sauce, :topping) def add_vegetable name @pizza.vegetable = name end #def add_sauce, add_cheese... def create_pizza name @pizza = Pizza.new(name) yield if block_given? end new_pizza 'Frango Catupiry' do add_vegetable 'tomatoes' add_sauce 'barbecue' add_cheese 'catupiry' add_topping 'chicken' end

Slide 50

Slide 50 text

Pizza = Struct.new(:name, :vegetable, :cheese, :sauce, :topping) def add_vegetable name @pizza.vegetable = name end #def add_sauce, add_cheese... def create_pizza name @pizza = Pizza.new(name) yield if block_given? end new_pizza 'Frango Catupiry' do add_vegetable 'tomatoes' add_sauce 'barbecue' add_cheese 'catupiry' add_topping 'chicken' end

Slide 51

Slide 51 text

Pizza = Struct.new(:name, :vegetable, :cheese, :sauce, :topping) def add_vegetable name @pizza.vegetable = name end #def add_sauce, add_cheese... def create_pizza name @pizza = Pizza.new(name) yield if block_given? end new_pizza 'Frango Catupiry' do add_vegetable 'tomatoes' add_sauce 'barbecue' add_cheese 'catupiry' add_topping 'chicken' end

Slide 52

Slide 52 text

Pizza = Struct.new(:name, :vegetable, :cheese, :sauce, :topping) def add_vegetable name @pizza.vegetable = name end #def add_sauce, add_cheese... def create_pizza name @pizza = Pizza.new(name) yield if block_given? end new_pizza 'Frango Catupiry' do add_vegetable 'tomatoes' add_sauce 'barbecue' add_cheese 'catupiry' add_topping 'chicken' end

Slide 53

Slide 53 text

2 grandes problemas

Slide 54

Slide 54 text

poluindo o namespace global

Slide 55

Slide 55 text

só um topping?

Slide 56

Slide 56 text

Cookbook.new_pizza "X-Tudo" do add_vegetable 'tomatoes' add_sauce 'barbecue' add_cheese 'cheddar' add_toppings 'chicken', 'peperoni', 'bacon' end

Slide 57

Slide 57 text

Cookbook.new_pizza "X-Tudo" do add_vegetable 'tomatoes' add_sauce 'barbecue' add_cheese 'cheddar' add_toppings 'chicken', 'peperoni', 'bacon' end

Slide 58

Slide 58 text

Cookbook.new_pizza "X-Tudo" do add_vegetable 'tomatoes' add_sauce 'barbecue' add_cheese 'cheddar' add_toppings 'chicken', 'peperoni', 'bacon' end

Slide 59

Slide 59 text

multiple arguments

Slide 60

Slide 60 text

multiple arguments def my_method *args puts args end my_method 1, 2, '3' #=> [1, 2, '3']

Slide 61

Slide 61 text

Proc/lambda times_two = Proc.new do |n| n * 2 end times_two = lambda do |n| n * 2 end times_two.call(2) #=> 4

Slide 62

Slide 62 text

ampersand square = Proc.new do |n| n ** 2 end [1, 2].each(square) #won't work [1, 2].each(&square)#will convert #the proc to a block

Slide 63

Slide 63 text

ampersand square = Proc.new do |n| n ** 2 end [1, 2].each(square) #won't work [1, 2].each(&square)#will convert #the proc to a block

Slide 64

Slide 64 text

class Alphabet def self.each_letter(&block) #converts block into proc ('A'..'Z').each(&block) #converts proc into block end end Alphabet.each_letter { |l| puts l } ampersand

Slide 65

Slide 65 text

class Alphabet def self.each_letter(&block) #converts block into proc ('A'..'Z').each(&block) #converts proc into block end end Alphabet.each_letter { |l| puts l } ampersand

Slide 66

Slide 66 text

class Alphabet def self.each_letter(&block) #converts block into proc ('A'..'Z').each(&block) #converts proc into block end end Alphabet.each_letter { |l| puts l } ampersand

Slide 67

Slide 67 text

class Alphabet def self.each_letter(&block) #converts block into proc ('A'..'Z').each(&block) #converts proc into block end end Alphabet.each_letter { |l| puts l } #=> 'A' #=> 'B' #=> 'C' ampersand

Slide 68

Slide 68 text

instance_eval

Slide 69

Slide 69 text

instance_eval class User attr_accessor :name end user = User.new user.name #=> nil user.instance_eval do @name = 'My new name' end user.name #=> 'My new name'

Slide 70

Slide 70 text

instance_eval class User attr_accessor :name end user = User.new user.name #=> nil user.instance_eval do @name = 'My new name' end user.name #=> 'My new name'

Slide 71

Slide 71 text

instance_eval class User attr_accessor :name end user = User.new user.name #=> nil user.instance_eval do @name = 'My new name' end user.name #=> 'My new name'

Slide 72

Slide 72 text

instance_eval class User attr_accessor :name end user = User.new user.name #=> nil user.instance_eval do @name = 'My new name' end user.name #=> 'My new name'

Slide 73

Slide 73 text

instance_eval class User attr_accessor :name end user = User.new user.name #=> nil user.instance_eval do @name = 'My new name' end user.name #=> 'My new name'

Slide 74

Slide 74 text

Cookbook.new_pizza "X-Tudo" do add_vegetable 'tomatoes' add_sauce 'barbecue' add_cheese 'cheddar' add_toppings 'chicken', 'peperoni', 'bacon' end

Slide 75

Slide 75 text

#pizza.rb class Pizza attr_accessor :name, :vegetable, :cheese, :sauce, :toppings def initialize name @name = name end def add_vegetable name @vegetable = name end def add_sauce name @sauce = name end def add_cheese name @cheese = name end def add_toppings *args raise "Too many toppings man!" if args.size > 4 @toppings = args end end

Slide 76

Slide 76 text

#pizza.rb class Pizza attr_accessor :name, :vegetable, :cheese, :sauce, :toppings def initialize name @name = name end def add_vegetable name @vegetable = name end def add_sauce name @sauce = name end def add_cheese name @cheese = name end def add_toppings *args raise "Too many toppings man!" if args.size > 4 @toppings = args end end

Slide 77

Slide 77 text

#pizza.rb class Pizza #... def add_toppings *args raise "Too many toppings man!" if args.size > 4 @toppings = args end end

Slide 78

Slide 78 text

#cookbook.rb class Cookbook @pizzas = [] def self.new_pizza name, &block pizza = Pizza.new(name) pizza.instance_eval(&block) if block_given? @pizzas << pizza end def self.pizzas @pizzas end end

Slide 79

Slide 79 text

#cookbook.rb class Cookbook @pizzas = [] def self.new_pizza name, &block pizza = Pizza.new(name) pizza.instance_eval(&block) if block_given? @pizzas << pizza end def self.pizzas @pizzas end end

Slide 80

Slide 80 text

#cookbook.rb class Cookbook @pizzas = [] def self.new_pizza name, &block pizza = Pizza.new(name) pizza.instance_eval(&block) if block_given? @pizzas << pizza end def self.pizzas @pizzas end end

Slide 81

Slide 81 text

#cookbook.rb class Cookbook @pizzas = [] def self.new_pizza name, &block pizza = Pizza.new(name) pizza.instance_eval(&block) if block_given? @pizzas << pizza end def self.pizzas @pizzas end end

Slide 82

Slide 82 text

Cookbook.new_pizza "X-Tudo" do add_vegetable 'tomatoes' add_sauce 'barbecue' add_cheese 'cheddar' add_toppings 'chicken', 'peperoni', 'bacon' end

Slide 83

Slide 83 text

DRY?

Slide 84

Slide 84 text

#pizza.rb class Pizza # ... def add_vegetable name @vegetable = name end def add_sauce name @sauce = name end def add_cheese name @cheese = name end # ... end

Slide 85

Slide 85 text

#pizza.rb class Pizza # ... def add_vegetable name @vegetable = name end def add_sauce name @sauce = name end def add_cheese name @cheese = name end # ... end

Slide 86

Slide 86 text

self send method_missing

Slide 87

Slide 87 text

No content

Slide 88

Slide 88 text

self

Slide 89

Slide 89 text

class User attr_accessor :name def forget_my_name! self.name = nil end end user = User.new user.name = 'Joao' user.name #=> 'Joao' user.forget_my_name! user.name #=> nil

Slide 90

Slide 90 text

class User attr_accessor :name def forget_my_name! self.name = nil end end user = User.new user.name = 'Joao' user.name #=> 'Joao' user.forget_my_name! user.name #=> nil

Slide 91

Slide 91 text

class User attr_accessor :name def forget_my_name! self.name = nil end end user = User.new user.name = 'Joao' user.name #=> 'Joao' user.forget_my_name! user.name #=> nil

Slide 92

Slide 92 text

class User attr_accessor :name def forget_my_name! self.name = nil end end user = User.new user.name = 'Joao' user.name #=> 'Joao' user.forget_my_name! user.name #=> nil

Slide 93

Slide 93 text

class User attr_accessor :name def forget_my_name! self.name = nil end end user = User.new user.name = 'Joao' user.name #=> 'Joao' user.forget_my_name! user.name #=> nil

Slide 94

Slide 94 text

class User attr_accessor :name def forget_my_name! self.name = nil end end user = User.new user.name = 'Joao' user.name #=> 'Joao' user.forget_my_name! user.name #=> nil

Slide 95

Slide 95 text

No content

Slide 96

Slide 96 text

self

Slide 97

Slide 97 text

No content

Slide 98

Slide 98 text

send

Slide 99

Slide 99 text

user = User.new user.name = 'Joao' user.name #=> "Joao" user.send 'name' #=> "Joao" user.send 'name=', 'Pedro' user.name #=> Pedro

Slide 100

Slide 100 text

user = User.new user.name = 'Joao' user.name #=> "Joao" user.send 'name' #=> "Joao" user.send 'name=', 'Pedro' user.name #=> Pedro

Slide 101

Slide 101 text

user = User.new user.name = 'Joao' user.name #=> "Joao" user.send 'name' #=> "Joao" user.send 'name=', 'Pedro' user.name #=> Pedro

Slide 102

Slide 102 text

user = User.new user.name = 'Joao' user.name #=> "Joao" user.send 'name' #=> "Joao" user.send 'name=', 'Pedro' user.name #=> Pedro

Slide 103

Slide 103 text

method_missing

Slide 104

Slide 104 text

class Comment def method_missing(method_name, *args) puts "Voce tentou chamar o metodo #{method_name} com os argumentos #{args}" end end comment = Comment.new comment.nao_existe_blabla 1, 3, '5' #=>Voce tentou chamar o metodo nao_existe_blabla com os argumentos [1,3,'5']

Slide 105

Slide 105 text

class Comment def method_missing(method_name, *args) puts "Voce tentou chamar o metodo #{method_name} com os argumentos #{args}" end end comment = Comment.new comment.nao_existe_blabla 1, 3, '5' #=>Voce tentou chamar o metodo nao_existe_blabla com os argumentos [1,3,'5']

Slide 106

Slide 106 text

class Comment def method_missing(method_name, *args) puts "Voce tentou chamar o metodo #{method_name} com os argumentos #{args}" end end comment = Comment.new comment.nao_existe_blabla 1, 3, '5' #=>Voce tentou chamar o metodo nao_existe_blabla com os argumentos [1,3,'5']

Slide 107

Slide 107 text

#pizza.rb class Pizza # ... def add_vegetable name @vegetable = name end def add_sauce name @sauce = name end def add_cheese name @cheese = name end # ... end

Slide 108

Slide 108 text

class Pizza #... private def method_missing method_sym, *args method_name = method_sym.to_s if method_name.start_with? "add_" attribute_name = method_name.split(/^add_/)[1] self.send(attribute_name + "=", args[0]) else super end end end

Slide 109

Slide 109 text

class Pizza #... private def method_missing method_sym, *args method_name = method_sym.to_s if method_name.start_with? "add_" attribute_name = method_name.split(/^add_/)[1] self.send(attribute_name + "=", args[0]) else super end end end

Slide 110

Slide 110 text

class Pizza #... private def method_missing method_sym, *args method_name = method_sym.to_s if method_name.start_with? "add_" attribute_name = method_name.split(/^add_/)[1] self.send(attribute_name + "=", args[0]) else super end end end

Slide 111

Slide 111 text

class Pizza #... private def method_missing method_sym, *args method_name = method_sym.to_s if method_name.start_with? "add_" attribute_name = method_name.split(/^add_/)[1] self.send(attribute_name + "=", args[0]) else super end end end

Slide 112

Slide 112 text

class Pizza #... private def method_missing method_sym, *args method_name = method_sym.to_s if method_name.start_with? "add_" attribute_name = method_name.split(/^add_/)[1] self.send(attribute_name + "=", args[0]) else super end end end

Slide 113

Slide 113 text

class Pizza #... private def method_missing method_sym, *args method_name = method_sym.to_s if method_name.start_with? "add_" attribute_name = method_name.split(/^add_/)[1] self.send(attribute_name + "=", args[0]) else super end end end

Slide 114

Slide 114 text

class Pizza #... private def method_missing method_sym, *args method_name = method_sym.to_s if method_name.start_with? "add_" attribute_name = method_name.split(/^add_/)[1] self.send(attribute_name + "=", args[0]) #pizza.cheese= 'cheddar' else super end end end

Slide 115

Slide 115 text

#pizza.rb class Pizza # ... def add_vegetable name @vegetable = name end def add_sauce name @sauce = name end def add_cheese name @cheese = name end # ... end

Slide 116

Slide 116 text

class Pizza ... private def method_missing method_sym, *args method_name = method_sym.to_s if method_name.start_with? "add_" attribute_name = method_name.split(/^add_/)[1] self.send(attribute_name + "=", args[0]) else super end end end

Slide 117

Slide 117 text

Cookbook.new_pizza "X-Tudo" do add_vegetable 'tomatoes' add_sauce 'barbecue' add_cheese 'cheddar' add_toppings 'chicken', 'peperoni', 'bacon' end

Slide 118

Slide 118 text

RSpec it "should start with 'a'" do expect(alphabet).to start_with("a") end

Slide 119

Slide 119 text

Cookbook.new_pizza "Frango Catupiry" do add_vegetable 'tomatoes' add_sauce 'barbecue' add_cheese 'catupiry' add_toppings 'chicken', 'bacon' bake_for(15.minutes).on(:high_temperature) end

Slide 120

Slide 120 text

#bake_time.rb class BakeTime attr_accessor :duration, :temperature def initialize duration @duration = duration end def on temperature @temperature = temperature end end

Slide 121

Slide 121 text

#bake_time.rb class BakeTime attr_accessor :duration, :temperature def initialize duration @duration = duration end def on temperature @temperature = temperature end end

Slide 122

Slide 122 text

#bake_time.rb class BakeTime attr_accessor :duration, :temperature def initialize duration @duration = duration end def on temperature @temperature = temperature end end

Slide 123

Slide 123 text

#bake_time.rb class BakeTime attr_accessor :duration, :temperature def initialize duration @duration = duration end def on temperature @temperature = temperature end end

Slide 124

Slide 124 text

class Pizza attr_accessor :bake_time, #:cheese... def bake_for duration @bake_time = BakeTime.new(duration) end #... end

Slide 125

Slide 125 text

class Pizza attr_accessor :bake_time, #:cheese... def bake_for duration @bake_time = BakeTime.new(duration) end #... end

Slide 126

Slide 126 text

Cookbook.new_pizza "Frango Catupiry" do add_vegetable 'tomatoes' add_sauce 'barbecue' add_cheese 'catupiry' add_toppings 'chicken', 'bacon' bake_for(15.minutes).on(:high_temperature) end

Slide 127

Slide 127 text

Cookbook.new_pizza "Frango Catupiry" do add_vegetable 'tomatoes' add_sauce 'barbecue' add_cheese 'catupiry' add_toppings 'chicken', 'bacon' bake_for(15.minutes).on(:high_temperature) end

Slide 128

Slide 128 text

Cookbook.new_pizza "Frango Catupiry" do add_vegetable 'tomatoes' add_sauce 'barbecue' add_cheese 'catupiry' add_toppings 'chicken', 'bacon' bake_for(15.minutes).on(:high_temperature) end

Slide 129

Slide 129 text

Cookbook.new_pizza "Frango Catupiry" do add_vegetable 'tomatoes' add_sauce 'barbecue' add_cheese 'catupiry' add_toppings 'chicken', 'bacon' bake_for(15.minutes).on(:high_temperature) end

Slide 130

Slide 130 text

Cookbook.new_pizza "Frango Catupiry" do add_vegetable 'tomatoes' add_sauce 'barbecue' add_cheese 'catupiry' add_toppings 'chicken', 'bacon' bake_for(15.minutes).on(:high_temperature) end

Slide 131

Slide 131 text

github.com/Ricardonacif/ pizza_cookbook_dsl

Slide 132

Slide 132 text

Obrigado! @ricardonacif [email protected]