Tips and Treats for New Developers

Transcript

1. Tips and tricks for new developers

2. David Padilla @dabit

3. @micheladaio

4. None
5. None
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7. Tips and tricks for new developers

8. A long time ago in a galaxy far, far away

9. 2009

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11. None

12. Solving the Riddle of Search: Using Sphinx with Rails The

    more complex your search queries becomes, the uglier your SQL statements get, even with ActiveRecord's helpful magic. Reclaim some clarity in your code by using the Sphinx search engine, a powerful tool that lets you search across your models in fast and complex ways.

13. Webrat: Rails Acceptance Testing Evolved Webrat, a Ruby DSL for

    interacting with Web applications, helps you write expressive, maintainable acceptance tests while sidestepping the issues traditionally associated with in-browser approaches like Selenium and Watir. We'll look at how you can use Webrat to develop a robust acceptance test suite to ensure your app stays working as you refactor mercilessly.

14. Smacking Git Around - Advanced Git Tricks Much of the

    Ruby and Rails community is now using Git, but there are a number of fun things that are a bit more difficult to get the hang of that are incredibly helpful to know when using Git. This session will go over some advanced Git usage for the casual or intermediate Git user.
15. None

16. Git is an open source, distributed version control system implemented

    as a directed acyclic graph of commit objects pointing to snapshots of content, with all data saved in it's own custom content addressable filesystem by the SHA-1 checksum hash of each objects data. Branches are simply pointers into this directed graph of commits, identifying entry points that designate the latest work on that branch, allowing Git to traverse the pointers, determining a coherent history. This makes branching cheap and easy, and merging simple, encouraging non-linear development styles and frictionless context switching while facilitating distributed development, cryptographic integrity and late decision making. Nearly all commands run locally with no network latency overhead and it is implemented mainly in C, making it incredibly fast and efficient even for very large projects. There are several large open source projects using it, not to mention the 100,000 open source repositories maintained by the 80,000 developers on GitHub alone. https://gist.github.com/schacon/111475

17. Mongrel 8080 8082 8083 8084 8085 8081

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19. N G I N X

20. H A P R O X Y

21. we need talks for beginners

22. This talk is for beginners

23. let’s begin

24. config files

25. rails new railsconf

26. None

27. config/database.yml $ cp config/database.yml config/database.sample.yml $ echo "config/database.yml" >> .gitignore

28. config/secrets.yml $ cp config/secrets.yml config/secrets.sample.yml $ echo "config/secrets.yml" >> .gitignore

29. config/payments.yml development: stripe_key: ABCXYZ test: stripe_key: ABCXYZ production: stripe_key: <%=

    ENV['STRIPE_KEY'] %>

30. config/payments.yml # Rails.application.config_for(:payments)['stripe_key'] => "ABCXYZ"

31. config/that_api.yml # Rails.application.config_for(:that_api)

32. wherever there’s a string or an integer

33. you probably want a constant or a setting

34. if registered_at < 30.minutes.ago # ... end

35. use a constant REGISTRATION_LIMIT = 30 if registered_at < REGISTRATION_LIMIT.minutes.ago

    # ... end

36. use a configuration file if registered_at < Rails.application.config_for(:registration)['limit'].minutes.ago # ...

    end

37. Database

38. Do not ignore db/schema.rb

39. You should always be able to restore db state with:

    $ rails db:setup or $ rails db:reset

40. Don’t change data in db migrations

41. Be careful when you change data in db migrations

42. def self.up add_column :companies, :zip_code, :integer add_column :companies, :name, :string

    Company.find(:all).each do |company| name, zip_code = company.code.split('-') company.update_attributes(name: name, zip_code: zip_code) end remove_column :companies, :code end

43. not future proof

44. def self.up add_column :companies, :zip_code, :integer add_column :companies, :name, :string

    Company.find(:all).each do |company| name, zip_code = company.code.split('-') company.update_attributes(name: name, zip_code: zip_code) end remove_column :companies, :code end

45. def self.up add_column :companies, :zip_code, :integer add_column :companies, :name, :string

    Company.find(:all).each do |company| name, zip_code = company.code.split('-') company.update_attributes(name: name, zip_code: zip_code) end remove_column :companies, :code end

46. Longer deploy times

47. def self.up add_column :companies, :zip_code, :integer add_column :companies, :name, :string

    Company.find(:all).each do |company| name, zip_code = company.code.split('-') company.update_attributes(name: name, zip_code: zip_code) end remove_column :companies, :code end

48. def self.up add_column :companies, :zip_code, :integer add_column :companies, :name, :string

    Company.find(:all).each do |company| name, zip_code = company.code.split('-') company.update_attributes(name: name, zip_code: zip_code) end remove_column :companies, :code end

49. Risk down time

50. def self.up add_column :companies, :zip_code, :integer add_column :companies, :name, :string

    Company.find(:all).each do |company| name, zip_code = company.code.split('-') company.update_attributes(name: name, zip_code: zip_code) end remove_column :companies, :code end

51. Prefer SQL over Ruby

52. def self.up add_column :companies, :zip_code, :integer add_column :companies, :name, :string

    execute <<EOS UPDATE companies SET name = SPLIT_PART(code, '-', 1), zip_code = SPLIT_PART(code, '-', 2) EOS remove_column :companies, :code end

53. def self.up add_column :companies, :zip_code, :integer add_column :companies, :name, :string

    execute <<EOS UPDATE companies SET name = SPLIT_PART(code, '-', 1), zip_code = SPLIT_PART(code, '-', 2) EOS remove_column :companies, :code end

54. gem 'rails-data-migrations'

55. $ rake -T data rake data:migrate # Apply pending data

    migrations rake data:migrate:down # Revert single data migration using VERSION rake data:migrate:pending # List pending migrations rake data:migrate:skip # Skip single data migration using VERSION rake data:migrate:up # Apply single data migration using VERSION

56. class AddActiveToAuthors < ActiveRecord::Migration[5.1] def change add_column :authors, :active, :boolean

    Author.update_all(active: true) end end

57. class AddActiveToAuthors < ActiveRecord::Migration[5.1] def change add_column :authors, :active, :boolean

    Author.update_all(active: true) end end

58. $ rails g data_migration set_authors_active create db/data_migrations/20170420185616_set_authors_active.rb

59. $ rails g data_migration set_authors_active create db/data_migrations/20170420185616_set_authors_active.rb

60. class SetAuthorsActive < ActiveRecord::DataMigration def up Author.update_all(active: true) end end

61. class AddActiveToAuthors < ActiveRecord::Migration[5.1] def change add_column :authors, :active, :boolean

    Author.update_all(active: true) end end
62. None
63. None

64. Background jobs

65. Do not pass objects to background jobs

66. class BigBadJob def perform(order, user) order.assign_to(user) # ... end end

67. class BigBadJob def perform(order_id, user_id) order = Order.find(order_id) user =

    User.find(user_id) order.assign_to(user) # ... end end

68. Deliver your email later

69. # # Rails 4 # class OrderMailer < ActionMailer::Base def

    confirmation(order, user) # ... end end

70. # # Rails 4 # class OrderMailer < ActionMailer::Base def

    confirmation(order_id, user_id) @order = Order.find(order_id) @user = User.find(user_id) # ... end end

71. # # Sidekiq or Delayed Job # OrderMailer.delay.confirmation(order_id, user_id)

72. # # Active Job # OrderMailer.confirmation(order_id, user_id).deliver_later

73. Be RESTful ALL THE TIME

74. REST

75. show new create edit update delete index

76. class ProductsController < ApplicationController def deactivate # ... end end

    # # config/routes.rb # Rails.application.routes.draw do resources :products do get :deactivate end end

77. class ProductStatesController < ApplicationController def update # ... end end

    # # config/routes.rb # Rails.application.routes.draw do resources :products do resource :status, only: :update, controller: :product_statuses end end

78. class CartsController < ApplicationController def apply_coupon # ... end end

    # # config/routes.rb # Rails.application.routes.draw do resource :cart do get :apply_coupon end end

79. class DiscountsController < ApplicationController def create # ... end end

    # # config/routes.rb # Rails.application.routes.draw do resource :cart do resource :discount, only: :create, controller: :cart_discounts end end

80. class ContactsController < ApplicationController def search # ... end end

    # # config/routes.rb # Rails.application.routes.draw do resources :contacts do get :search end end

81. class Contacts::SearchesController < ApplicationsController def show # ... end end

    # # config/routes.rb # Rails.application.routes.draw do resources :contacts namespace :contacts do resource :search, only: :show end end

82. show new create edit update delete index

83. gems you must

84. rubocop

85. rubocop --auto-gen-config

86. .rubocop_todo.yml

87. # # .rubocop.yml # inherit_from: .rubocop_todo.yml

88. None

89. $ echo "inherit_from: .rubocop_todo.yml" >> .rubocop.yml

90. None

91. # # .rubocop.yml # Metrics/LineLength: Max: 130

92. # # .rubocop_todo.yml # Style/Documentation: Exclude: - 'spec/**/*' - 'test/**/*'

    - 'app/controllers/application_controller.rb' - 'app/helpers/application_helper.rb' - 'app/mailers/application_mailer.rb' - 'app/models/application_record.rb' - 'config/application.rb'

93. # # .rubocop.yml # Style/Documentation: Enabled: false

94. # # .rubocop.yml # Metrics/MethodLength: Max: 10

95. .git/hooks/pre-push #!/bin/bash rubocop

96. annotate

97. None
98. None

99. # == Schema Information # # Table name: users #

    # id :integer not null, primary key # name :string # username :string # password :string # active :boolean # created_at :datetime not null # updated_at :datetime not null # class User < ApplicationRecord end

100. $ annotate --routes

101. # == Route Map # # Prefix Verb URI Pattern

     Controller#Action # contacts GET /contacts(.:format) contacts#index # POST /contacts(.:format) contacts#create # new_contact GET /contacts/new(.:format) contacts#new # edit_contact GET /contacts/:id/edit(.:format) contacts#edit # contact GET /contacts/:id(.:format) contacts#show # PATCH /contacts/:id(.:format) contacts#update # PUT /contacts/:id(.:format) contacts#update # DELETE /contacts/:id(.:format) contacts#destroy # contacts_search GET /contacts/search(.:format) contacts/searches#show # cart_discount POST /cart/discount(.:format) cart_discounts#create # new_cart GET /cart/new(.:format) carts#new # edit_cart GET /cart/edit(.:format) carts#edit # cart GET /cart(.:format) carts#show # PATCH /cart(.:format) carts#update # PUT /cart(.:format) carts#update # DELETE /cart(.:format) carts#destroy # POST /cart(.:format) carts#create # product_status PATCH /products/:product_id/status(.:format) product_statuses#update # PUT /products/:product_id/status(.:format) product_statuses#update # products GET /products(.:format) products#index # POST /products(.:format) products#create # new_product GET /products/new(.:format) products#new # edit_product GET /products/:id/edit(.:format) products#edit # product GET /products/:id(.:format) products#show # PATCH /products/:id(.:format) products#update # PUT /products/:id(.:format) products#update # DELETE /products/:id(.:format) products#destroy # Rails.application.routes.draw do resources :contacts namespace :contacts do resource :search, only: :show end resource :cart do resource :discount, only: :create, controller: :cart_discounts end resources :products do resource :status, only: :update, controller: :product_statuses end end

102. bullet

103. detects n+1 problem as it happens

104. # == Schema Information # # Table name: books #

     # id :integer not null, primary key # title :string # description :text # author_id :integer # created_at :datetime not null # updated_at :datetime not null # class Book < ApplicationRecord belongs_to :author has_many :comments end

105. # == Schema Information # # Table name: authors #

     # id :integer not null, primary key # name :string # created_at :datetime not null # updated_at :datetime not null # class Author < ApplicationRecord end

106. # == Schema Information # # Table name: comments #

     # id :integer not null, primary key # book_id :integer # user_id :integer # comment :text # created_at :datetime not null # updated_at :datetime not null # class Comment < ApplicationRecord belongs_to :user belongs_to :book end
107. None

108. class BooksController < ApplicationController def index @books = Book.all end

     end
109. None

110. Started GET "/books" for 127.0.0.1 at 2017-04-18 13:33:52 -0700 Processing

     by BooksController#index as HTML Rendering books/index.html.erb within layouts/application Book Load (0.3ms) SELECT "books".* FROM "books" Author Load (0.1ms) SELECT "authors".* FROM "authors" WHERE "authors"."id" = ? L Comment Load (0.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."book_i User Load (0.1ms) SELECT "users".* FROM "users" WHERE "users"."id" = ? LIMIT ? Author Load (0.1ms) SELECT "authors".* FROM "authors" WHERE "authors"."id" = ? L Comment Load (0.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."book_i CACHE User Load (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = ? LIM CACHE Author Load (0.0ms) SELECT "authors".* FROM "authors" WHERE "authors"."id" Comment Load (0.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."book_i CACHE User Load (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = ? LIM CACHE Author Load (0.0ms) SELECT "authors".* FROM "authors" WHERE "authors"."id" Comment Load (0.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."book_i CACHE User Load (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = ? LIM Author Load (0.1ms) SELECT "authors".* FROM "authors" WHERE "authors"."id" = ? L Comment Load (0.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."book_i CACHE User Load (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = ? LIM Rendered books/index.html.erb within layouts/application (19.0ms) Completed 200 OK in 30ms (Views: 26.4ms | ActiveRecord: 1.5ms)

111. Started GET "/books" for 127.0.0.1 at 2017-04-18 13:33:52 -0700 Processing

     by BooksController#index as HTML Rendering books/index.html.erb within layouts/application Book Load (0.3ms) SELECT "books".* FROM "books" Author Load (0.1ms) SELECT "authors".* FROM "authors" WHERE "authors"."id" = ? L Comment Load (0.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."book_i User Load (0.1ms) SELECT "users".* FROM "users" WHERE "users"."id" = ? LIMIT ? Author Load (0.1ms) SELECT "authors".* FROM "authors" WHERE "authors"."id" = ? L Comment Load (0.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."book_i CACHE User Load (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = ? LIM CACHE Author Load (0.0ms) SELECT "authors".* FROM "authors" WHERE "authors"."id" Comment Load (0.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."book_i CACHE User Load (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = ? LIM CACHE Author Load (0.0ms) SELECT "authors".* FROM "authors" WHERE "authors"."id" Comment Load (0.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."book_i CACHE User Load (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = ? LIM Author Load (0.1ms) SELECT "authors".* FROM "authors" WHERE "authors"."id" = ? L Comment Load (0.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."book_i CACHE User Load (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = ? LIM Rendered books/index.html.erb within layouts/application (19.0ms) Completed 200 OK in 30ms (Views: 26.4ms | ActiveRecord: 1.5ms)

112. gem 'bullet' config.after_initialize do Bullet.enable = true Bullet.console = true

     Bullet.rails_logger = true Bullet.add_footer = true end
113. None
114. None

115. class BooksController < ApplicationController def index @books = Book.includes(:author, comments:

     :user) end end

116. Started GET "/books" for 127.0.0.1 at 2017-04-18 13:42:06 -0700 Processing

     by BooksController#index as HTML Rendering books/index.html.erb within layouts/application Book Load (0.1ms) SELECT "books".* FROM "books" Author Load (0.2ms) SELECT "authors".* FROM "authors" WHERE "authors"."id" IN (1, Comment Load (0.2ms) SELECT "comments".* FROM "comments" WHERE "comments"."book_i User Load (0.2ms) SELECT "users".* FROM "users" WHERE "users"."id" = 1 Rendered books/index.html.erb within layouts/application (61.6ms) Completed 200 OK in 92ms (Views: 73.1ms | ActiveRecord: 3.5ms)

117. Started GET "/books" for 127.0.0.1 at 2017-04-18 13:42:06 -0700 Processing

     by BooksController#index as HTML Rendering books/index.html.erb within layouts/application Book Load (0.1ms) SELECT "books".* FROM "books" Author Load (0.2ms) SELECT "authors".* FROM "authors" WHERE "authors"."id" IN (1, Comment Load (0.2ms) SELECT "comments".* FROM "comments" WHERE "comments"."book_i User Load (0.2ms) SELECT "users".* FROM "users" WHERE "users"."id" = 1 Rendered books/index.html.erb within layouts/application (61.6ms) Completed 200 OK in 92ms (Views: 73.1ms | ActiveRecord: 3.5ms)

118. oink

119. detect memory leaks before its too late

120. Gemfile gem 'oink'

121. config/initializers/oink.rb Rails.application.middleware.use(Oink::Middleware, :logger => Rails.logger)

122. Started GET "/books" for 127.0.0.1 at 2017-04-18 13:46:08 -0700 (0.1ms)

     SELECT "schema_migrations"."version" FROM "schema_migrations" ORDER BY " Processing by BooksController#index as HTML Rendering books/index.html.erb within layouts/application Book Load (0.2ms) SELECT "books".* FROM "books" Author Load (0.1ms) SELECT "authors".* FROM "authors" WHERE "authors"."id" IN (1, Comment Load (0.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."book_i User Load (0.1ms) SELECT "users".* FROM "users" WHERE "users"."id" = 1 Rendered books/index.html.erb within layouts/application (50.1ms) Completed 200 OK in 116ms (Views: 94.4ms | ActiveRecord: 2.6ms) Oink Action: books#index Memory usage: 2596436 | PID: 31331 Instantiation Breakdown: Total: 14 | Book: 5 | Comment: 5 | Author: 3 | User: 1 Oink Log Entry Complete

123. Started GET "/books" for 127.0.0.1 at 2017-04-18 13:46:08 -0700 (0.1ms)

     SELECT "schema_migrations"."version" FROM "schema_migrations" ORDER BY " Processing by BooksController#index as HTML Rendering books/index.html.erb within layouts/application Book Load (0.2ms) SELECT "books".* FROM "books" Author Load (0.1ms) SELECT "authors".* FROM "authors" WHERE "authors"."id" IN (1, Comment Load (0.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."book_i User Load (0.1ms) SELECT "users".* FROM "users" WHERE "users"."id" = 1 Rendered books/index.html.erb within layouts/application (50.1ms) Completed 200 OK in 116ms (Views: 94.4ms | ActiveRecord: 2.6ms) Oink Action: books#index Memory usage: 2596436 | PID: 31331 Instantiation Breakdown: Total: 14 | Book: 5 | Comment: 5 | Author: 3 | User: 1 Oink Log Entry Complete

124. That’s all!

125. THANK YOU David Padilla @dabit david@michelada.io