Ruby on Rails 6: Learn 25+ gems and build a Startup MVP 2020

0 AWS Cloud9

# All AWS C9 envments
https://eu-central-1.console.aws.amazon.com/cloud9/home?region=us-east-1

# Instance management
https://console.aws.amazon.com/ec2/home?region=eu-central-1#Instances:sort=instanceId

# Create AWS C9 environment
https://eu-central-1.console.aws.amazon.com/cloud9/home/create

Setting - set tabs to 2
Ctrl+E to search file
Alt+T - new terminal
Alt+W - close current tab
Ctrl+] - next tab
Ctrl+[ - prev tab
Ctrl+D - delete current line of code

1 Install RoR 6

# install latest version of Ruby, Rails, Postgresql, Yarn, Webpacker
rails -v
ruby -v
rvm list
rvm install ruby-2.7.2
rvm --default use 2.7.2
rvm uninstall 2.7.1
rvm uninstall 2.7.0
rvm uninstall 2.6.3
rvm uninstall 2.6.5
gem install rails -v 6.0.3
gem update rails
gem update --system
curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | sudo apt-key add -
echo "deb https://dl.yarnpkg.com/debian/ stable main" | sudo tee /etc/apt/sources.list.d/yarn.list
sudo apt update
sudo apt install postgresql libpq-dev redis-server redis-tools yarn
ruby -v
rails -v
pg_config --version

2 Create app, configure PostgreSQL

# create rails app
rails new myappname --database=postgresql
cd myappname
bundle
yarn

# postgresql setup
sudo su postgres
createuser --interactive
ubuntu
y 
exit

# to make the server work, add the url to development.rb
config.hosts << "2b8c1faf3a934c25b7e01d446161bfff.vfs.cloud9.us-east-1.amazonaws.com"

# start server
rails db:create 
rails db:migrate
rails s

2 Install RoR5

#Ruby on Rails
rvm install ruby-2.7.1
rvm --default use 2.7.1
rvm uninstall 2.6.5
rvm uninstall 2.6.6
rvm uninstall 2.6.3
gem install rails -v 5.2.4.3

#Postgresql
sudo apt install postgresql libpq-dev
sudo su postgres
createuser --interactive
ubuntu
y 
exit

3 github

http://github.com/

git config --global user.name "Yaro"
git config --global user.email yshmarov@gmail.com

git init
git status
git add -A
git commit -m 'initialize app'
# https://github.com/new
git remote add origin https://github.com/yshmarov/rubygems.git
git push -u origin main

// delete last commit from github
git reset HEAD^ --hard
git push -f

// git uncheck last commit
git reset --soft HEAD~1

// git reset to specific commit
git reset --hard c14809fa

// forward-moving undo last commit 
git revert HEAD
git add -A
git commit -m 'undo last commit'

// forward-moving undo commit-before-last-commit 
git revert HEAD~1
git add -A
git commit -m 'undo commit-before-last-commit'

//check to which repo you are connected
git remote -v
//set remote repo
git remote set-url origin https://github.com/yshmarov/edurge.git

Git branches:
//Create branch
git checkout -b "i18n"
//Show all branches: 
git branch
//Switch to master 
git checkout master
//Merge "i18n" with master 
git merge i18n
//Delete "i18n" branch 
git branch -D i18n

4 Install Heroku and push

http://heroku.com/

### If watchers error - Increasing the amount of inotify watchers

[Go Here] (https://github.com/guard/listen/wiki/Increasing-the-amount-of-inotify-watchers)
 
# creating the first page
rails g controller home index
# Add the following line to routes.rb
root 'home#index'

git add -A
git commit -m 'add home index controller'

# installing heroku
npm uninstall -g heroku-cli
sudo snap install heroku --classic
npm install -g heroku

# If you’d prefer to stay in the CLI to enter your credentials, you may run heroku login -i
heroku login -i
heroku: Enter your login credentials
Email: me@example.com
Password: ***************
Two-factor code: ********
Logged in as me@heroku.com


heroku create
heroku buildpacks:add heroku/ruby
git remote -v
git push heroku main
heroku run rake db:migrate

# if you want to connect to an existing heroku app
heroku git:remote -a yourappnamegoeshere

# see logs
heroku logs --tail
# to run console activerecord commands
heroku run rails c
# restart
heroku restart

# log into heroku from console
heroku login -i

action_text!

https://edgeguides.rubyonrails.org/action_text_overview.html

// Console
rails action_text:install

// application.js
require("trix")
require("@rails/actiontext")

// actiontext.scss
@import "trix/dist/trix";

// application.scss
@import "./actiontext.scss";

// app/models/course.rb
class Course < ApplicationRecord
  has_rich_text :description
end

// app/views/courses/_form.html.erb
<%= f.label :description %>
<%= f.rich_text_area :description %>

add alerts and notices

// application.html.haml
= render 'layouts/messages'

// _messages.html.haml
- flash.each do |name, msg|
  - if msg.is_a?(String)
    %div{:class => "alert alert-#{name.to_s == 'notice' ? 'success' : 'danger'}", :role => "alert"}
      %button.close{"aria-hidden" => "true", "data-dismiss" => "alert", :type => "button"} ×
      = content_tag :div, msg, :id => "flash_#{name}"

basic search in navbar

// courses_controller.rb

def index
  if params[:title]
    @courses = Course.where('title ILIKE ?', "%#{params[:title]}%") #case-insensitive
  else
    @courses = Course.all
  end
end

// _header.html.haml

.form-inline.my-2.my-lg-0
  = form_tag(courses_path, method: :get) do
    .input-group
      = text_field_tag :title, params[:title], autocomplete: 'off', placeholder: "Find a course", class: 'form-control-sm'
      %span.input-group-append
        %button.btn.btn-primary.btn-sm{:type => "submit"}
          %span.fa.fa-search{"aria-hidden" => "true"}

credentials

CREATE CREDENTIALS & EDIT

rails credentials:edit 
EDITOR=vim rails credentials:edit

WORKING WITH VIM

For inserting
Press i //Do required editing
For exiting
Press Esc
:wq //for exiting and saving
:q! //for exiting without saving

FIND A CREDENTIAL

rails c
Rails.application.credentials.dig(:aws, :access_key_id)
or if an env variable is used
Rails.application.credentials[Rails.env.to_sym][:aws][:access_key_id]

In production:
heroku config:set RAILS_MASTER_KEY=123456789
or
heroku config:set RAILS_MASTER_KEY=`cat config/master.key`

search by an attribute!

// courses_controller.rb

def index
  if params[:name]
    @courses = Course.published.approved.where('name ILIKE ?', "%#{params[:name]}%") #case-insensitive
    #@courses = Course.where('name LIKE ?', "%#{params[:name]}%") #case-sensitive
    #@courses = Course.where('LOWER(name) LIKE LOWER(?)', "%#{params[:name]}%") #make lowercase
  else
    @courses = Course.published.approved.all
  end
end

// in any view:

.form-inline.my-2.my-lg-0
  = form_tag(posts_path, method: :get) do
    .input-group
      = text_field_tag :name, params[:name], autocomplete: 'off', placeholder: "Find a post", class: 'form-control-sm'
      %span.input-group-append
        %button.btn.btn-primary.btn-sm{:type => "submit"}
          %span.fa.fa-search{"aria-hidden" => "true"}

selectize js tags

1. Migrations & configuration

rails g migration create_tags name course_tags_count:integer

	, null: false, default: 0

rails g migration create_course_tags course:references tag:references

course.rb
	has_many :course_tags, inverse_of: :course, dependent: :destroy
	has_many :tags, through: :course_tags

tag.rb

class Tag < ApplicationRecord
	has_many :course_tags
	has_many :courses, through: :course_tags
	validates :name, length: {minimum: 1, maximum: 25}, uniqueness: true
	def to_s
		name
	end
	def popular_name
	  "#{name.to_s}: #{course_tags_count.to_s}"
	end

course_tag.rb
  #Tag.find_each { |tag| Tag.reset_counters(tag.id, :course_tags) }
  belongs_to :tag, counter_cache: true
  belongs_to :course

routes.rb

  resources :tags

courses_controller.rb

, course_tag_ids: []

_course.html.haml

  = link_to tag.name, tag_path(tag), class: 'text-white'
  /= link_to tag.name, courses_path(courses_search: {s: 'enrollments_count desc'})

rails c

Tag.create(name: "Programming")
Tag.create(name: "English")
Tag.create(name: "Literature")

2. Select tags with selectize js

yarn add selectize

app/assets/stylesheets/application.scss:

@import "selectize/dist/css/selectize";
@import "selectize/dist/css/selectize.default";

javascript/packs/application.js

require("selectize")
require("packs/tags")

javascript/packs/tags.js

$(document).on("turbolinks:load", function() {
  if ($('.selectize')){
      $('.selectize').selectize({
          sortField: 'text'
      });
  }

  $(".selectize-tags").selectize({
    create: function(input, callback) {
      $.post('/tags.json', { tag: { name: input } })
        .done(function(response){
          console.log(response)
          callback({value: response.id, text: response.name });
        })
    }
  });
});

course/form.html.haml

	= f.select :tag_ids, Tag.all.pluck(:name, :id), {}, { multiple: true, class: "selectize-tags" }

wicked_pdf heroku

// gemfile:

gem 'wicked_pdf' #PDF for Ruby on Rails
gem 'wkhtmltopdf-binary', group: :development
gem 'wkhtmltopdf-heroku', group: :production

config/wicked_pdf.rb

WickedPdf.config ||= {}
WickedPdf.config.merge!({
  #YOUR CONFIG HERE
})