Story for a Ruby on Rails Single Engineer

Ruby on Rails Single Engineer story

1. Ruby on Rails
The Single Engineer Framework
Radoslav Stankov

2. !

3. Radoslav Stankov
@rstankov rstankov.com

4. https://tips.rstankov.com

6. I began my web development career using
Flash, PHP, and JavaScript at an agency in
Dobrich in 2002.

7. I was 15 "

8. ... after 22 years #

9. here some of the technologies, I
have worked with...

11. Careers in tech are long, and technology trends come and go.
You won't be able to have a meaningful career working with a single
technology your whole career.

13. - one developer (me) $
- management portal %
- implement a mobile app &
- for iOS ' / Android (

14. Building mapping )
Mobile app &
Issue tracker *
Employees +
Bulletin board ,
Notifications -
Taxation .
Contacts /
Omni search 0
Reporting 1
Printing 2
Bookkeeping 3
Voting 4
Financials 5
Homebook 6
Debtors 7
Bulk operations ⚙
Messaging 9
Calendar :
Funds ;
ePay / EasyPay <
Bank imports =
Invoicing >
Warranty Issues ?

Technicians @

Individual accounts A
Business accounts )
Audit logs B

Archiving C
Trials D
Demo E

I18n F G H

Marketing site I

15. & Mobile stack J

16. % Web stack J

17. Ruby on Rails and its ecosystem enabled me to develop Angry Building
single-handedly. It felt like having a cheat code.

19. Ruby on Rails

20. Ruby on Rails

21. Ruby on Rails

22. Ruby on Rails

23. Ruby
Ruby is an interactive, object-
oriented programming language.
Its motto is:
"Optimized for programmer
happiness"

24. https://rubygems.org/

25. Ruby on Rails
Ruby on Rails is a web application framework.

27. Who uses Ruby? K

30. ... Ruby on Rails old and boring,
designed for monoliths L

31. https://newsletter.pragmaticengineer.com/p/what-is-old-is-new-again

32. https://newsletter.pragmaticengineer.com/p/what-is-old-is-new-again

34. ... one interesting story

35. ... one interesting story
... maybe $

38. https://github.com/maybe-finance/maybe

39. Ruby

40. M Syntax
N Symbols
N Blocks
O Expressions
P Everything is object
Q Open classes

41. Variables
a = 1 # Number
b = "string" # String
c = [1, 2, 3, 4] # Array
d = { key: 'value' } # Hash

42. Symbols
a = :key
hash[:key]

43. Everything is an object
person.name
"string".size
array.empty?
array[0] == array.first
array[1] == array.second
array[array.size - 1] == array.last
1.day.ago
1.day.ago - 2.hours

44. puts("string")
puts "string"
Method calling

45. Blocks
5.times { puts "Ruby is cool!" }
5.times do
puts "Ruby is cool!"
end

46. Blocks
[1,2,3,4].each { |value| puts value }
# => [1, 2, 3, 4]
[1,2,3,4].map { |value| value * value }
# => [1, 4, 9, 16]
[1,2,3,4].reduce { |a, b| a + b }
# => 10

47. Blocks
[1,2,3,4].each { puts _1 }
# => [1, 2, 3, 4]
[1,2,3,4].map { _1 * _1 }
# => [1, 4, 9, 16]
[1,2,3,4].reduce { _1 + _1 }
# => 10

48. Blocks
File.open('file.txt') do |file|
file.write 'content'
end

49. Blocks
File.open('file.txt') do |file|
file << 'content'
end

50. Blocks
File.open('file.txt') do
_1 << 'content'
end

51. Blocks
File.open('file.txt') { _1 << 'content' }

52. Blocks
def method_with_block(value)
yield value
end
value = method_with_block( 5) { |v| v + 4 }
puts value # 9

53. Blocks
def method_with_block(value, &block)
block.call(value)
end
value = method_with_block( 5) { |v| v + 4 }
puts value # 9

54. Expressions
def explain_number(value)
if value % 2
result = 'even'
else
result = 'odd'
end
return result
end

55. Expressions
def explain_number(value)
if value % 2
result = 'even'
else
result = 'odd'
end
result
end

56. Expressions
def explain_number(value)
if value.even?
result = 'even'
else
result = 'odd'
end
result
end

57. Expressions
def explain_number(value)
result = if value.even?
'even'
else
'odd'
end
result
end

58. Expressions
def explain_number(value)
if value.even?
'even'
else
'odd'
end
end

59. Expressions
def error_message(value)
if !value.present?
return nil
end
return 'value is empty'
end

60. Expressions
def error_message(value)
if !value.present?
return nil
end
'value is empty'
end

61. Expressions
def error_message(value)
unless value.present?
return nil
end
'value is empty'
end

62. Expressions
def error_message(value)
return nil unless value.present?
'value is empty'
end

63. Expressions
def error_message(value)
return unless value.present?
'value is empty'
end

64. Expressions
def error_message(value)
'value is empty' if value.blank?
end

65. Expressions
def error_message(value)
return 'value is empty' if value.blank?
return "value #{value} is to long" if value.size > 100
end

66. Expressions
def error_message(value)
if value.blank?
'value is empty'
elsif value.size > 100
"value #{value} is to long"
end
end

67. Classes
me = Person.new("Radoslav", "Stankov")

me.first_name # Radoslav
me.last_name # Stankov
me.full_name # Radoslav Stankov

68. class Person
def initialize(first_name, last_name)
@first_name = first_name
@last_name = last_name
end
def first_name
@first_name
end
def first_name=(value)
@first_name = value
end
Classes

69. @first_name
end
def first_name=(value)
@first_name = value
end
def last_name
@last_name
end
def last_name=(value)
@last_name = value
end
def full_name
"#{first_name} + #{last_name}"
end
end
Classes

70. Classes
class Person
attr_reader :first_name, :last_name
attr_writer :first_name, :last_name
def initialize(first_name, last_name)
@first_name = first_name
@last_name = last_name
end
def full_name
"#{first_name} + #{last_name}"
end
end

71. Classes
class Person
attr_accessor :first_name, :last_name
def initialize(first_name, last_name)
@first_name = first_name
@last_name = last_name
end
def full_name
"#{first_name} + #{last_name}"
end
end

72. Meta programming
class Person
attr_accessor :first_name, :last_name
end

74. Meta Programming

75. R Nothing is special
S Everything is an object
T No definitions, just executions
U Cool syntax V
Meta programming

76. Open classes
class Array
def first
self[0]
end
def second
self[1]
end
end
array = [1, 2, 3, 4]
array.first # 1
array.second # 2

77. class MyClass
puts "I'll be executed"
unless RUBY_VERSION >= "3.3.3"

puts "I'll be executed after ruby 3.3.3 "
def some_method
# ... code
end
end
end
No definitions, just executions

78. Meta programming
class Person
attr_accessor :first_name, :last_name
end

79. Meta programming
class Person
def first_name
@first_name
end
def first_name=(value)
@first_name = value
end
end

80. Meta programming
class Person
define_method(:first_name) do
@first_name
end
define_method(:first_name=) do |value|
@first_name = value
end
end

81. Meta programming
class Person
define_method(:first_name) do
instance_variable_get( :@first_name)
end
define_method(:first_name=) do |value|
instance_variable_set( :@first_name, value)
end
end

82. Meta programming
class Person
define_method(:first_name) do
instance_variable_get :@first_name
end
define_method(:first_name=) do |value|
instance_variable_set :@first_name, value
end
end

83. Meta programming
class Person
attr_accessor :first_name, :last_name
end

84. Meta programming
class Person
def self.attr_accessor(attribute)
define_method(attribute) do
instance_variable_get :"@#{attribute}"
end
define_method(:"#{attribute}=") do |value|
instance_variable_set :"@#{attribute}", value
end
end
end

85. Meta programming
class Person
def self.attr_accessor(*attributes)
attributes.each do |attribute|
define_method(attribute) do
instance_variable_get :"@#{attribute}"
end
define_method(:"#{attribute}=") do |value|
instance_variable_set :"@#{attribute}", value
end
end
end
end

86. Meta programming
class Person
attr_accessor :first_name, :last_name
end

92. W Model View Controller (MVC)
X Batteries included
Y Convention over configuration
Z Extendible platform

93. W Model View Controller (MVC)

94. W Model View Controller (MVC)

95. W Model View Controller (MVC)

96. W Model View Controller (MVC)

97. W Model View Controller (MVC)

98. W Model View Controller (MVC)

99. W Model View Controller (MVC)

100. W Model View Controller (MVC)

101. W Model View Controller (MVC)

102. W Model View Controller (MVC)

104. ActiveSupport - utilities
ActiveModel - base model & validations
ActiveRecord - object relation mapper (ORM)
ActiveJob - background job processing
ActiveStorage - file uploads
ActionController - Controller from MVC
ActionView - View from MVC
ActionMailer - Sending emails
ActionMailbox - Receiving & processing emails
ActionCable - Web Socket & real time
ActionText - Rich text editing
Propshaft - assets delivery
I18n - internalization
X Batteries included

105. Y Convention over configuration

106. https://github.com/maybe-finance/maybe
https://github.com/discourse/discourse
https://github.com/forem/forem
https://github.com/mastodon/mastodon
https://github.com/thoughtbot/upcase
https://github.com/feedbin/feedbin
https://gitlab.com/gitlab-org/gitlab
Open Source Apps

107. https://blog.rstankov.com/top-8-ruby-on-rails-engines/
Z Extendible platform

108. Sidekiq

109. Blazer

110. Lookbook

111. Flipper

112. GraphiQL

113. ... and a lot more ✨

114. https://rubygems.org/

116. rails new blog
rails generate scaffold post title:string content:text

118. db/migrate/[...]_create_posts.rb
class CreatePosts < ActiveRecord::Migration[7.1]
def change
create_table :posts do |t|
t.string :title, null: false
t.text :content, null: false
t.timestamps
end
end
end

119. rails db:migrate

121. class Post < ApplicationRecord
validates :title, presence: true
validates :content, presence: true
end
app/models/post.rb

122. Rails.application.routes.draw do
resources :posts
# Define your application routes per the DSL in
# https://guides.rubyonrails.org/routing.html
# Reveal health status on /up that returns 200
# if the app boots with no exceptions, otherwise 500.
# Can be used by load balancers and uptime monitors to
# verify that the app is live.
get "up" => "rails/health#show", as: :rails_health_check
# Defines the root path route ("/")
# root "posts#index"
end
config/routes.rb

123. class PostsController < ApplicationController
# GET /posts
def index
@posts = Post.all
end
# GET /posts/1
def show
@post = Post.find(params[:id])
end
# GET /posts/new
def new
@post = Post.new
end
# GET /posts/1/edit
def edit
@post = Post.find(params[:id])
end
# POST /posts
def create
@post = Post.new(post_params)
app/controllers/posts_controller.rb

124. # POST /posts
def create
@post = Post.new(post_params)
if @post.save
redirect_to post_url( @post), notice: "Post was successfully created. "
else
render :new, status: :unprocessable_entity
end
end
# PATCH/PUT /posts/1
def update
@post = Post.find(params[:id])
if @post.update(post_params)
redirect_to post_url( @post), notice: "Post was successfully updated. "
else
render :edit, status: :unprocessable_entity
end
end
# DELETE /posts/1
def destroy
app/controllers/posts_controller.rb

125. if @post.update(post_params)
redirect_to post_url( @post), notice: "Post was successfully updated. "
else
render :edit, status: :unprocessable_entity
end
end
# DELETE /posts/1
def destroy
@post = Post.find(params[:id])
@post.destroy!
redirect_to posts_url, notice: "Post was successfully destroyed. "
end
private
def post_params
params.require(:post).permit(:title, :content)
end
end
app/controllers/posts_controller.rb

126. <p style="color: green"><%= notice %></p>
<h1>Posts</h1>
<div id="posts">
<% @posts.each do |post| %>
<%= render post %>
<p>
<%= link_to "Show this post", post %>
</p>
<% end %>
</div>
<%= link_to "New post", new_post_path %>
app/views/posts/index.html.erb

127. <%= form_with(model: post) do |form| %>
<% if post.errors.any? %>
<div style="color: red">
<h2><%= pluralize(post.errors.count, "error") %> prohibited this post from being saved: </h2>
<ul>
<% post.errors.each do |error| %>
<li><%= error.full_message %></li>
<% end %>
</ul>
</div>
<% end %>
<div>
<%= form.label :title, style: "display: block" %>
<%= form.text_field :title %>
</div>
<div>
<%= form.label :content, style: "display: block" %>
<%= form.text_area :content %>
</div>
<div>
<%= form.submit %>
</div>
<% end %>
app/views/posts/_form.html.erb

128. rails server

138. rails action_text:install

140. bundle

142. rails server

144. class Post < ApplicationRecord
validates :title, presence: true
validates :content, presence: true
has_rich_text :content
end
app/models/post.rb

145. <%= form_with(model: post) do |form| %>
<% if post.errors.any? %>
<div style="color: red">
<h2><%= pluralize(post.errors.count, "error") %> prohibited this post from being saved: </h2>
<ul>
<% post.errors.each do |error| %>
<li><%= error.full_message %></li>
<% end %>
</ul>
</div>
<% end %>
<div>
<%= form.label :title, style: "display: block" %>
<%= form.text_field :title %>
</div>
<div>
<%= form.label :content, style: "display: block" %>
<%= form.rich_text_area :content %>
</div>
<div>
<%= form.submit %>
</div>
<% end %>
app/views/posts/_form.html.erb

148. https://rubyonrails.org/

149. Learning resources

150. https://tips.rstankov.com

151. https://www.youtube.com/watch?v=X2sgQ38UDVY

152. https://bit.ly/4cznIfA

154. https://rubybanitsa.com/

156. https://balkanruby.com/

157. https://rstankov.com/appearances