• User the right ruby version: rvm use 2.6.x where x is your installed minor version rvm list rubies to see installed rubies

• Check rails version: rails -v, it should be 5.2

• Then rails new path/to/project, can be just: rails new lgm_redmine to create the project in current folder

• The root of the project (or "racine" in French), is the lgm_redmine folder created above.

Some options

These can be used with the rails new command:

• --database=mysql : preconfigure project with specified database (postgresql, mysql...), sqlit3 by default
• --api : generate a smaller stack to use Rails as a backend API only
• --webpacker=react : preconfigure project with webpack and a JS framework (react, vue, angular...)
• --help : to see all the options

Clone project from github Do a bundle install, check if it is running ok

• Exercice solutions

• Rails and MVC presentation

• New project

• What is defined? and &. trick, quickly explain that rails had its own method .try

• Explain what rails new project did

• Discover Rails architecture

• launch server: rails server or just rails s (options: -p 3001 -b 0.0.0.0)

• Define main route

• Create a controller and an action

• Create a view

• Explain rescue_from

• Generate a model, explain what it does (with a published thing) rails g model Project title:string archive:boolean description:text rake db:create rake db:migrate

• Explain validations, show example in console: rails console or just rails c - show error because of database not null constraint doc

• Explain migrations, generate a new migration to edit previously created table: rails g migration add_slug_to_projects 'slug:string{60}' rake db:migrate doc

• Explain callbacks, show an example

p = Project.create(title: "Super project")
p2 = Project.create(title: SecureRandom::hex(64))
p2.destroy
p.delete # explain diff

• Use seed and explain rake db:seed

• Play with active record in console doc

• Explain scopes, show an example

Exercice 1

• Create the Task model, with a title, a content and a priority (integer)
• Add a seed to create some tasks
• Add a validation (a task should have a title, and a priority from 0 to 5)
• Add a two scopes:
• one named most_importants (show tasks with priority 4 or 5)
• one named by_priority (to order tasks by priority)

• Explain how the layout works, show content_for? / content_for & yield(...)
• Replace with a @variable
• Add some style
• Explain helpers
• Explain partials

Exercice 2

• Create a partial for the footer
• Add some styling to the footer (nothing too fancy)

• Explain routes.rb, show rails routes / rails routes -g, add a resources, show differences with only, except. Add some member/collection routes. Explain admin namespace
• Create the index / new / show / edit / update / form logic
• Show byebug

Exercice 3

• Let them handle the logic for tasks

Solution

• Explain scaffold, use it to solve the exercice
• Explain what it creates by default (and rails formats)

• Explain associations, associate project and tasks
• Explain build, create (with has_one / has_many)
• Explain:

.where().first_or_create
.find_or_create_by()

• Add tasks number in projects index
• Explain N+1 problem and its solution (2 solutions, with includes & counter_cache)
• Explain diff between .length .count .size (maybe with .explain)
• Nested tasks, usefull partial, counter cache, moving tasks and a bit of coffee

Exercice 4

• Generate a new Category model using scaffold, with just a name:string property
• Create a join table between categories and projects, command:

rails g migration CreateJoinTableCategoryProject category project

• Use the has_and_belongs_to_many association
• Create a category (from console or web app)
• Try: Category.first.projects << Project.last in a rails console and try to understand what it does
• Try another time the same command... see what happens
• How could we prevent this problem? - maybe with this?
• Remove data with: Category.first.projects.delete(Project.last)
• Add a projects list in the category show page

-- End ex 4 --

• Explain how to add a select field in project form to select several categories

• Explain rubygems, Gemfile & bundler, launch doc server: gem server, if no doc: gem rdoc --all

• Install devise gem (for authentication), add a "admin" boolean

• add a "private" part (only viewable by current user)

• Install letter opener

• We now have authentication

• Add some authed part, with some secret data

• Display a logo somewhere

Exercice 5

• Add an attachment to projects
• Only allow admin to see that field in the form
• How would you prevent the update of that field from the controller by normal/guest users?

-- End ex5 --

• Explain how to display the image
• Send a notification to users linked to a project when a task is created (explain Action Mailer), add an attachment
• Explain TDD
• Explain translations (i18n)
• Show usual gems

• Explain how to create API
• Explain documentation
• Use another db
• Explain rails/rake tasks (and create one - for cronjobs for instance)
• Explain turbolinks
• Explain concerns
• Explain default security in Rails
• Explain how to deploy with capistrano
• Add CSS framework (zurb foundation)
• Add a lib through webpacker
• Action Cable
• Active Job
• logger

• slim - indented html
• simple_form - simple way to create forms (detect validations...)
• cocoon - simple way to handle nested models in forms, works great with simple_form
• gon - easy way to give some JS info from Rails to JS code
• will_paginate - handle pagination
• devise - authentication
• devise_masquerade - masquerade
• pundit - authorizations
• rolify - roles management
• prawn - pdf generator

In dev

• annotate - add some info to your models
• byebug - debug
• rspec - unit tests
• factory bot - simple way to create data in unit tests
• guard - a watcher that can be extended
• guard livereload / rack livereload - livereload
• letter opener - to see and get emails when developing
• rails best practices - to check your code and propose some improvements
• brakeman - to check your code for vulnerabilities
• bundler-audit - to check existing CVE in used gems
• rubocop - to check code syntax
• rubocop-rails_config - to configure rubocop with same configs as the official rails repo
• bullet - logs N+1 problems

For deployment

• capistrano - best tool to deploy an app in ruby
• capistrano-rvm
• capistrano-yarn
• capistrano-bundler
• capistrano-rails
• capistrano-rake