Rubocop loading issue on VScode

If you are facing issue to load rubocop plugin to your VS code try the following steps to fix it.

The error message will be something like:

rubocop on VScode not working.Error “rubocop is not executable”

  1. First you have to ensure that you have installed ruby in your machine. if you are using docker containers for your project, ruby is installed inside the containers and VS Code cannot find it.
  2. Next install rubocop gem in your machine
                 $ gem install rubocop

3. Next take

  VS Code -> Settings -> search for 'rubocop' in Ruby > Rubocop: Execute Path

add the output of the following command:

        $ which rubocop

4. Reload the rubocop plugin from VS Code.

Now VS Code will get to execute rubocop.

A Ruby on Rails Application without models

This blog is a quick walkthrough of creating a Ruby On Rails application without a model.

Find Rails new options from here:

Find Gemfile options from here:

Install Ruby/Rails using rbenv

$ touch .rbenv-gemsets
$ echo project-name > .rbenv-gemsets
$ rbenv gemset active
$ rbenv install 2.5.3
$ gem install bundler
$ rbenv rehash
$ gem install rails -v 5.2.9
$ rbenv rehash
$ rails new my-new-porject --skip-active-record --skip-bundle -v 5.2.9

Add in Gemfile:

ruby “2.5.3”

comment jbuilder, we don’t need it.

# gem 'jbuilder', '~> 2.8’

Move rbenv gems file to new rails app folder

$ mv .rbenv-gemsets my-new-porject

$ touch .ruby-version

$ echo 2.5.3 > .ruby-version

$ gem install bundler

$ bundle

$ ruby -v
ruby 2.5.3p105 (2018-10-18 revision 65156) [x86_64-darwin18]

Start Rails server:

$ rails s

Gemfile add:

# Bootstrap Theme

gem 'bootstrap', '~> 4.3.0’

# Slim template Engine

gem 'slim', '>=4.0.1’

Do Bundle Install

$ bundle

Rename css to scss because we use bootsrap mixins and variables that work with scss files

$ mv app/assets/stylesheets/application.css app/assets/stylesheets/application.scss

Import Bootstrap styles in app/assets/stylesheets/application.scss:

// Custom bootstrap variables must be set or imported *before* bootstrap.
@import "bootstrap";

Then, remove all the *= require and *= require_tree statements from the Sass file. Instead, use @import to import Sass files.

Bootstrap JavaScript depends on jQuery
Add jquery-rails to Gemfile:

gem 'jquery-rails', '~> 4.3.4’

Bootstrap tooltips and popovers depend on popper.js for positioning.
Add Bootstrap dependencies and Bootstrap to your application.js:

//= require jquery3
//= require popper
//= require bootstrap-sprockets

While bootstrap-sprockets provides individual Bootstrap components for ease of debugging, you may alternatively require the concatenated bootstrap for faster compilation:

//= require jquery3
//= require popper
//= require bootstrap

Sass: Individual components

All Bootstrap opponents will be imported by default.
You can also import components explicitly. To start with a full list of modules copy _bootstrap.scss file into your assets as _bootstrap-custom.scss. Then comment out components you do not want from _bootstrap-custom. In the application Sass file, replace @import ‘bootstrap’ with:

@import 'bootstrap-custom';

Your application.css:

 * This is a manifest file that'll be compiled into application.css, which will include all the files
 * listed below.
 * Any CSS and SCSS file within this directory, lib/assets/stylesheets, or any plugin's
 * vendor/assets/stylesheets directory can be referenced here using a relative path.
 * You're free to add application-wide styles to this file and they'll appear at the bottom of the
 * compiled file so the styles you add here take precedence over styles defined in any other CSS/SCSS
 * files in this directory. Styles in this file should be added after the last require_* statement.
 * It is generally better to create a new file per style scope.

/*Custom bootstrap variables must be set or imported *before* bootstrap.
  The available variables can be found:
@import "bootstrap";

Your application.js File:

// This is a manifest file that'll be compiled into application.js, which will include all the files
// listed below.
// Any JavaScript/Coffee file within this directory, lib/assets/javascripts, or any plugin's
// vendor/assets/javascripts directory can be referenced here using a relative path.
// It's not advisable to add code directly here, but if you do, it'll appear at the bottom of the
// compiled file. JavaScript code in this file should be added after the last require_* statement.
// Read Sprockets README ( for details
// about supported directives.
//= require rails-ujs
//= require turbolinks
//= require_tree .
//= require jquery3
//= require popper
//= require bootstrap-sprockets

You can check sample bootstrap forms here:

Remove cable.js from javascripts # we don’t need this for now

Two ways to load files in Rails

There are two ways that files get loaded in Rails:

It is registered in the autoload process, and you reference a constant that corresponds to the file name. For instance, if you have app/controllers/pages_controller.rb and reference PagesController, app/controllers/pages_controller.rb will automatically be loaded. This happens for a preset list of directories in the load path. This is a feature of Rails, and is not part of the normal Ruby load process.
Files are explicitly required. If a file is required, Ruby looks through the entire list of paths in your load paths, and find the first case where the file you required is in the load path. You can see the entire load path by inspecting $LOAD_PATH (an alias for $:).

Since lib is in your load path, you have two options: either name your files with the same names as the constants, so Rails will automatically pick them up when you reference the constant in question, or explicitly require the module.

I also notice that you might be confused about another thing. ApplicationController is not the root object in the system. Observe:

module MyModule
  def im_awesome
    puts "#{self} is so awesome"
class ApplicationController < ActionController::Base
  include MyModule

class AnotherClass
# NoMethodError: undefined method `im_awesome' for #

You will need to include the module into whatever class you want to use it in.

class AnotherClass
  include MyModule
# AnotherClass is so awesome

Of course, in order to be able to include the module in the first place, you’ll need to have it available (using either of the techniques above).

Reference: This note is from a blog/site that I looked for some knowledge.

Get information about your Rails Environment

To get information about your Rails Environment Rails, Ruby, Rack versions use the following command,

$ rake about

About your application's environment
Ruby version 1.9.2 (i686-linux)
RubyGems version 1.8.10
Rack version 1.3
Rails version 3.1.3
JavaScript Runtime therubyracer (V8)
Active Record version 3.1.3
Action Pack version 3.1.3
Active Resource version 3.1.3
Action Mailer version 3.1.3
Active Support version 3.1.3
Middleware Rack::Cache, ActionDispatch::Static, Rack::Lock, Rack::Runtime, Rack::MethodOverride, Rails::Rack::Logger, ActionDispatch::ShowExceptions, ActionDispatch::RemoteIp, Rack::Sendfile, ActionDispatch::Reloader, ActionDispatch::Callbacks, ActiveRecord::ConnectionAdapters::ConnectionManagement, ActiveRecord::QueryCache, ActionDispatch::Cookies, ActionDispatch::Session::CookieStore, ActionDispatch::Flash, ActionDispatch::ParamsParser, ActionDispatch::Head, Rack::ConditionalGet, Rack::ETag, ActionDispatch::BestStandardsSupport, Warden::Manager, OmniAuth::Builder
Application root /home/abhi/my_app
Environment development
Database adapter mysql2
Database schema version 20120704103548