Ruby on Rails

Motivation: The core framework used for GitLab’s web application. Learn about its structure, conventions, and common libraries used.

Structure:

• app/: Contains the core application logic, controllers, models, views, and helpers.
• config/: Holds configuration files like database.yml, routes.rb, and environments/*.rb.
• db/: Stores database schemas, migrations, and seeds.
• lib/: Provides reusable code modules and libraries.
• public/: Contains static files such as images, CSS, and JavaScript.
• test/: Houses test suites for the application’s functionality.
• vendor/: Includes external dependencies and gems.

Conventions:

• Model-View-Controller (MVC): A common architectural pattern separating concerns for data, presentation, and user interactions.
• RESTful Routing: A convention for defining routes and actions based on HTTP verbs (GET, POST, PUT, DELETE).
• Active Record: An Object-Relational Mapper (ORM) simplifying database interactions.
• ActiveRecord Associations: Defines relationships between models such as has_many, belongs_to, has_one.
• Gemfile: A file managing application dependencies and gems.

Common Libraries and Tools:

• Action Pack: Provides the foundation for controllers, views, and routing.
• Active Support: Offers utility classes and extensions to Ruby core functionality.
• Active Record: Manages database interactions.
• Action Mailer: Facilitates email sending within the application.
• Action View: Renders HTML templates and assists with view logic.
• Action Cable: Enables real-time communication features using WebSockets.
• Rake: A build and task management tool.
• Capistrano: Deploys Rails applications to servers.
• Sidekiq: A background worker queue.

Code Examples:

• app/controllers/projects_controller.rb: Contains actions for managing projects, such as creating, updating, and deleting.

class ProjectsController < ApplicationController
            def index
              @projects = Project.all
            end
          
            def show
              @project = Project.find(params[:id])
            end
          
            # ...
          end
          

• app/models/project.rb: Defines the Project model, including its attributes and relationships.

class Project < ApplicationRecord
            has_many :issues
            has_many :users, through: :members
          
            # ...
          end
          

• config/routes.rb: Defines application routes and their corresponding actions.

Rails.application.routes.draw do
            resources :projects do
              resources :issues
            end
          end
          

• db/migrate/20231207123456_create_projects.rb: A database migration for creating the Project table.

class CreateProjects < ActiveRecord::Migration[7.0]
            def change
              create_table :projects do |t|
                t.string :name
                t.timestamps
              end
            end
          end
          

• Gemfile: Lists the application’s dependencies and gems.

source 'https://rubygems.org'
          
          gem 'rails', '~> 7.0'
          gem 'sqlite3'
          gem 'rspec-rails'
          gem 'factory_bot_rails'
          gem 'faker'
          
          # ...
          

References:

• Ruby on Rails Guides
• GitLab Source Code
• Rails API Documentation