• https://aws.amazon.com/cloud9
• https://eu-south-1.console.aws.amazon.com/cloud9/home/product?ad=c&cp=bn&p=c9&region=eu-south-1#
• https://eu-south-1.console.aws.amazon.com/cloud9/ide/cf7e24b3df894167a884d128c4695a65

rvm get stable

rvm install 3.1.2

rvm --default use 3.1.2

echo "gem: --no-document" >> .gemrc

gem install rails -v 7.0.3

gem install bundler -v 2.3.15

source <(curl -sL https://cdn.learnenough.com/resize)

rails _7.0.3_ new hello_app --skip-bundle

• As of Rails 6 and continuing in Rails 7, running rails new automatically initializes a Git repository:

rm -r hello_app/.git

• This would install the latest version of the capybara gem (which is used in testing) as long as it’s greater than or equal to version 3.26—even if it’s, say, version 7.2.

gem "capybara", ">= 3.26"

• This installs the gem sqlite3 as long as it’s version 1.4 or newer (a “minor update”) but not 2 or newer (a “major update”). In other words, the >= notation always installs the latest gem as long as it meets the minimum version requirement, whereas the ~> 1.4 notation will install 1.5 (if available) but not 2.0.

gem "sqlite3", "~> 1.4"

• https://github.com/learnenough/rails_tutorial_7th_edition_gemfiles

cd hello_app/ && bundle install

bin/rails server

• To view the result of rails server on a native OS, paste the URL http://localhost:3000 into the address bar of your browser. On the cloud IDE, go to Preview and click on Preview Running Application and then open it in a full browser window or tab (https://cf7e24b3df894167a884d128c4695a65.vfs.cloud9.eu-south-1.amazonaws.com).

• Look for all controllers available

ls app/controllers/*_controller.rb

• Example of how to define the route root:

root "controller_name#action_name"

• Update Git on Cloud9:

source <(curl -sL https://cdn.learnenough.com/upgrade_git)

git config --global --list

credential.helper=!aws codecommit credential-helper $@
credential.usehttppath=true
core.editor=nano

• Configure the name and email fields for Git:

$ git config --global user.name "Your Name"
$ git config --global user.email your.email@example.com

• Define the default branch's name:

git config --global init.defaultBranch main

• Set up git co as a checkout alias:

git config --global alias.co checkout

• Configure Git to remember passwords for a set length of time:

git config --global credential.helper "cache --timeout=86400"

• Prevent the local installation of any production gems (which in this case consists of the pg gem):

bundle config

• Bundling without production gems:

bundle _2.3.14_ config set --local without 'production'

bundle _2.3.14_ install

bundle _2.3.14_ lock --add-platform x86_64-linux

• See if your system already has the Heroku command-line client installed:

heroku --version

• Install Heroku on the cloud IDE:

source <(curl -sL https://cdn.learnenough.com/heroku_install)

• https://devcenter.heroku.com/articles/heroku-cli#install-the-heroku-cli

• On a native system:

heroku login

• On the cloud IDE:

heroku login --interactive

Email: <your email>
Password: <your API Key, NOT your Heroku password>

• Create and configure a new application at Heroku:

heroku create

• Push the main branch up to Heroku:

git push heroku main

• If something goes wrong, inspect the logs:

heroku logs

• Get info about the Heroku app, including the Web URL:

heroku apps:info

• https://young-badlands-92881.herokuapp.com

• https://www.learnenough.com/custom-domains

• Generate a random subdomain with Ruby:

('a'..'z').to_a.shuffle[0..7].join

• Rename the application

heroku rename learn-enough-rails_hello-app

• https://learn-enough-rails-hello-app.herokuapp.com
• David Heinemeier Hansson using scaffolding in Rails

rails new toy_app --skip-bundle

cd toy_app

bundle config set --local without 'production'

bundle install

• https://marketplace.visualstudio.com/items?itemName=EditorConfig.EditorConfig + https://stackoverflow.com/a/54696441/1904223 + https://youtu.be/_fcQDS1iTPw

toy_app/bin/rails s

git commit -am "Add hello"

heroku create

git push && git push heroku main

heroku rename learn-enough-rails-toy-app

• https://learn-enough-rails-toy-app.herokuapp.com + https://dashboard.heroku.com/apps/learn-enough-rails-toy-app

rails generate scaffold User name:string email:string

rails db:migrate

heroku run rails db:migrate

• The correspondence between pages and URLs for the Users resource:

URL	Action	Purpose
/users	index	page to list all users
/users/1	show	page to show user with id 1
/users/new	new	page to make a new user
/users/1/edit	edit	page to edit user with id 1

• RESTful routes provided by the Users resource:

HTTP request method	URL	Action	Purpose
GET	/users	index	page to list all users
GET	/users/1	show	page to show user with id 1
GET	/users/new	new	page to make a new user
POST	/users	create	create a new user
GET	/users/1/edit	edit	page to edit user with id 1
PATCH	/users/1	update	update user with id 1
DELETE	/users/1	delete	delete user with id 1

rails generate scaffold Micropost content:text user_id:integer

rails db:migrate

• Undo a single migration step:

rails db:rollback

• Go all the way back to the beginning:

rails db:migrate VERSION=0

• Try to insert a text longer than 140 characters into the Content textarea at http://127.0.0.1:3000/microposts/new then submit the form.

cd toy_app && rails console

User.first

User.create!(name: 'Cos', email: 'mail@costi.com')

micropost = User.first.microposts.first

• The inheritance hierarchy for the User and Micropost models:

• The inheritance hierarchy for the Users and Microposts controllers:

rails new sample_app --skip-bundle

rm -rf sample_app/.git

• Download from Github using curl

curl --location --remote-header-name https://raw.githubusercontent.com/learnenough/rails_tutorial_7th_edition_gemfiles/master/sample_app/Gemfile_initial --output sample_app/Gemfile

• Skip the pg gem for PostgreSQL in development and use SQLite for development and testing:

bundle config set --local without 'production'

bundle install

• https://github.com/learnenough/rails_tutorial_sample_app_7th_ed/blob/main/README.md
• Easily include static pages in your Rails app

rails generate controller StaticPages home help

• The inheritance hierarchy for the Static Pages:

• Undo the created controller:

rails destroy controller StaticPages home help

• Rails shortcuts:

Full command	Shortcut
rails server	rails s
rails console	rails c
rails generate	rails g
rails test	rails t
bundle install	bundle

• http://127.0.0.1:3000/static_pages/home
• http://127.0.0.1:3000/static_pages/help
• https://dhh.dk/2014/tdd-is-dead-long-live-testing.html

mv app/views/layouts/application.html.erb layout_file

• https://stackoverflow.com/questions/27814500/ruby-on-rails-provide-vs-content-for

mv layout_file app/views/layouts/application.html.erb

• https://github.com/kern/minitest-reporters
• https://github.com/guard/guard
• https://www.railstutorial.org/guardfile

bundle exec guard init

curl --location --remote-header-name https://raw.githubusercontent.com/learnenough/rails_tutorial_sample_app_7th_ed/main/Guardfile --output Guardfile

bundle exec guard

• https://www.learnenough.com/ruby
• https://en.wikipedia.org/wiki/Media_type
• https://en.wikipedia.org/wiki/Abstraction_layer
• stylesheet_link_tag(*sources)
• https://www.learnenough.com/text-editor

nano ~/.irbrc

cat ~/.irbrc

IRB.conf[:PROMPT_MODE] = :SIMPLE
IRB.conf[:AUTO_INDENT_MODE] = false

rails console

curl -o app/assets/images/rails.svg -L https://cdn.learnenough.com/rails.svg

curl -OL https://cdn.learnenough.com/kitten.jpg

touch app/assets/stylesheets/custom.scss

• https://github.com/rails/sprockets/blob/main/guides/how_sprockets_works.md

• Inside of sample_app\app\assets\stylesheets\application.css the line *= require_tree . ensures that all CSS files in the app/assets/stylesheets directory (including the tree subdirectories) are included into the application.css. The line *= require_self specifies where in the loading sequence the CSS in application.css itself gets included.

• Route and URL mapping for site links:

Page	URL	Named route
Home	/	root_path
About	/about	about_path
Help	/help	help_path
Contact	/contact	contact_path
Sign up	/signup	signup_path
Log in	/login	login_path

• Generate a template test, called 'site_layout':

rails generate integration_test site_layout

• https://www.rubydoc.info/gems/capybara/Capybara%2FNode%2FMatchers:assert_selector

rails test:integration

rails generate controller Users new

• https://github.com/heartcombo/devise#starting-with-rails

rails generate model User name:string email:string

rails db:migrate

• DB Browser for SQLite

• Explore the data models is the Rails console:

rails console --sandbox

user = User.new

user.valid?

• Save the User object to the database:

user.save

• Find User by id:

User.find(1)

• Active Record allows to find users by specific attributes:

User.find_by(email: 'michael@example.com')

User.first

User.first

user.email = "mhartl@example.net"

user.email = "mhartl@example.net"

user.save

user.reload.email

user.update(name: "The Dude", email: "dude@abides.org")

rails test:models

rails console --sandbox

user = User.new(name: "", email: "michael@example.com")

user.valid?

user.errors.full_messages

• Rubular: a Ruby regular expression editor

rails generate migration add_index_to_users_email

rails db:migrate

• https://en.wikipedia.org/wiki/Hash_function
• https://en.wikipedia.org/wiki/Cryptographic_hash_function

rails generate migration add_password_digest_to_users password_digest:string

• https://en.wikipedia.org/wiki/Bcrypt
• https://github.com/bcrypt-ruby/bcrypt-ruby

bundle install

• Creating and authenticating a user:

rails console

User.create(name: "Cos tin", email: "costin@ymail.com", password: "testingPwd", password_confirmation: "testingPwd")

User.find_by(email: 'costin@ymail.com').password_digest

User.find_by(email: 'costin@ymail.com').authenticate('wrongPwd')

User.find_by(email: 'costin@ymail.com').authenticate('testingPwd')

!!User.find_by(email: 'costin@ymail.com').authenticate('testingPwd')

• Rails comes equipped with three environments: test, development, and production. The default environment for the Rails console is development.

• To run a console in a different environment (to debug a test, for example), you can pass the environment as an option to the console script:

rails console --environment test

• If you have deployed your sample app to Heroku, you can see its environment using heroku run rails console.

puts User.find_by(email: 'costin@ymail.com').attributes.to_yaml

or

y User.find_by(email: 'costin@ymail.com').attributes

• A Users resource:

User.count

User.first

• rdbg + http://atdot.net/~ko1/activities/2021_rubyconf.pdf + https://edgeguides.rubyonrails.org/debugging_rails_applications.html#entering-a-debugging-session

(rdbg) @user.name
"Cos tin"
(rdbg) @user.email
"costin@ymail.com"
(rdbg)

• Gravatar URLs are based on an MD5 hash of the user's email address
• https://rubyapi.org/3.1/o/digest/md5
• https://rubyapi.org/3.1/o/string#method-i-downcase
• https://rubyapi.org/3.1/o/string#method-i-strip
• https://api.rubyonrails.org/classes/String.html#method-i-squish

rails console

user = User.first

user.update(name: 'Constantin', email: "constantin@gmail.com", password: "parolaDemo", password_confirmation: 'parolaDemo')

• https://thoughtbot.com/upcase/videos/ruby-keyword-arguments
• https://api.rubyonrails.org/classes/ActionView/Helpers/FormHelper.html#method-i-form_with
• Soft-deprecated:
  • https://guides.rubyonrails.org/form_helpers.html#using-form-tag-and-form-for
  • rails/rails#25197
  • https://api.rubyonrails.org/classes/ActionView/Helpers/FormHelper.html#method-i-form_for
  • https://api.rubyonrails.org/classes/ActionView/Helpers/FormTagHelper.html#method-i-form_tag
• https://stackoverflow.com/questions/941594/understanding-the-rails-authenticity-token
• http://www.railsstatuscodes.com/unprocessable_entity.html
• https://guides.rubyonrails.org/layouts_and_rendering.html#the-status-option
• https://api.rubyonrails.org/classes/ActionController/Parameters.html#method-i-require
• https://api.rubyonrails.org/classes/ActionController/Parameters.html#method-i-permit
• http://127.0.0.1:3000/signup?admin=1

user = User.new(name: "The coder", email: "mail@void", password: "ruby", password_confirmation: "ruby")

user.save

user.errors.full_messages

• https://api.rubyonrails.org/classes/ActiveRecord/Associations/CollectionProxy.html#method-i-any-3F
• https://api.rubyonrails.org/classes/ActiveRecord/Associations/CollectionProxy.html#method-i-empty-3F
• https://api.rubyonrails.org/classes/ActionView/Helpers/TextHelper.html#method-i-pluralize

rails generate integration_test users_signup

• https://api.rubyonrails.org/classes/ActionController/Redirecting.html#method-i-redirect_to

• https://api.rubyonrails.org/classes/ActionDispatch/Flash.html

• Reset the database:

rails db:migrate:reset

• https://api.rubyonrails.org/classes/ActiveSupport/Testing/Assertions.html#method-i-assert_difference

• https://api.rubyonrails.org/classes/ActionView/Helpers/TagHelper.html#method-i-content_tag

• SSL (Secure Sockets Layer) is now TLS (Transport Layer Security)

• https://www.learnenough.com/custom-domains

• https://devcenter.heroku.com/articles/deploying-rails-applications-with-the-puma-web-server

• https://devcenter.heroku.com/articles/getting-started-with-rails6

• Production deployment:

rails test
git add -A
git commit -m "Use SSL and the Puma web server in production"
git push && git push heroku
heroku run rails db:migrate

• How to reset the production database:

heroku pg:reset DATABASE
heroku run rails db:migrate

• URL for the production version of chapter 7 (sign up)

• Generate the Sessions controller:

rails generate controller Sessions new

rails routes -c users
   Prefix Verb   URI Pattern               Controller#Action
   signup GET    /signup(.:format)         users#new
    users GET    /users(.:format)          users#index
          POST   /users(.:format)          users#create
 new_user GET    /users/new(.:format)      users#new
edit_user GET    /users/:id/edit(.:format) users#edit
     user GET    /users/:id(.:format)      users#show
          PATCH  /users/:id(.:format)      users#update
          PUT    /users/:id(.:format)      users#update
          DELETE /users/:id(.:format)      users#destroy

rails routes -c sessions
      Prefix Verb   URI Pattern             Controller#Action
sessions_new GET    /sessions/new(.:format) sessions#new
       login GET    /login(.:format)        sessions#new
             POST   /login(.:format)        sessions#create
      logout DELETE /logout(.:format)       sessions#destroy

curl -I http://127.0.0.1:3000 | grep Set-Cookie

• https://guides.rubyonrails.org/security.html#session-storage
• https://guides.rubyonrails.org/security.html#replay-attacks-for-cookiestore-sessions
• https://guides.rubyonrails.org/action_controller_overview.html#session
• https://github.com/rails/activerecord-session_store
• https://api.rubyonrails.org/classes/ActiveRecord/FinderMethods.html#method-i-find_by

rails generate integration_test users_login

• Session replay attack
• https://guides.rubyonrails.org/security.html#session-fixation