Story for a Ruby on Rails Single Engineer

Ruby on Rails
The Single Engineer Framework
Radoslav Stankov

Radoslav Stankov
@rstankov rstankov.com

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

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

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.

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

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

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

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

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

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

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

... one interesting story
... maybe $

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

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

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

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

puts("string")
puts "string"
Method calling

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

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

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

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

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

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

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

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

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

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

Expressions
if value % 2
result = 'even'
else
result = 'odd'
end
result
end

Expressions
if value.even?
result = 'even'
else
result = 'odd'
end
result
end

Expressions
result = if value.even?
'even'
else
'odd'
end
result
end

Expressions
if value.even?
'even'
else
'odd'
end
end

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

Expressions
if !value.present?
return nil
end
'value is empty'
end

Expressions
unless value.present?
return nil
end
'value is empty'
end

Expressions
return nil unless value.present?
'value is empty'
end

Expressions
return unless value.present?
'value is empty'
end

Expressions
'value is empty' if value.blank?
end

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

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

Classes
me = Person.new("Radoslav", "Stankov")
me.first_name # Radoslav
me.last_name # Stankov
me.full_name # Radoslav Stankov

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

end
@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

Classes
class Person
attr_reader :first_name, :last_name
attr_writer :first_name, :last_name
end
def full_name
end
end

Classes
class Person
attr_accessor :first_name, :last_name
end
def full_name
end
end

Meta programming
class Person
attr_accessor :first_name, :last_name
end

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

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

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

Meta programming
class Person
def first_name
@first_name
end
@first_name = value
end
end

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

Meta programming
class Person
instance_variable_get(:@first_name)
end
instance_variable_set(:@first_name, value)
end
end

Meta programming
class Person
instance_variable_get :@first_name
end
instance_variable_set :@first_name, value
end
end

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

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

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

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

Y Convention over configuration

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

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

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

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

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

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

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
end
# POST /posts
def create app/controllers/posts_controller.rb

# POST /posts
def create
@post = Post.new(post_params)
if @post.save
redirect_to post_url(@post), notice: "Post was successfully cr
else
render :new, status: :unprocessable_entity
end
end
# PATCH/PUT /posts/1
def update
if @post.update(post_params)
redirect_to post_url(@post), notice: "Post was successfully up
else
render :edit, status: :unprocessable_entity
end
end
# DELETE /posts/1
app/controllers/posts_controller.rb

if @post.update(post_params)
redirect_to post_url(@post), notice: "Post was successfully up
else
render :edit, status: :unprocessable_entity
end
end
# DELETE /posts/1
def destroy
@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

<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

<%= form_with(model: post) do |form| %>
<% if post.errors.any? %>
<div style="color: red">
<h2><%= pluralize(post.errors.count, "error") %> prohibited this post from bei
<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

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

<%= form_with(model: post) do |form| %>
<% if post.errors.any? %>
<div style="color: red">
<h2><%= pluralize(post.errors.count, "error") %> prohibited this post from bei
<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

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

https://rstankov.com/appearances

Story for a Ruby on Rails Single Engineer

More Related Content

Similar to Story for a Ruby on Rails Single Engineer

Story for a Ruby on Rails Single Engineer