Ruby on Rails Tutorial for Beginners

What you'll Learn

1. What is Ruby on Rails?

• Ruby on Rails, or just Rails, is a web application framework written in Ruby. It’s designed to speed up web app development by providing built-in tools and conventions.
• Rails follow the MVC (Model-View-Controller) architecture, which separates data (Model), user interface (View), and logic (Controller).

2. Setting Up Your Environment

• To start with Rails, you must install Ruby, Rails, and a database like SQLite.
• Once installed, you can create a new Rails app with a simple command.

3. Creating a New Rails App

• Start by generating a new Rails project using the command:
  • rails new project_name
• This sets up the entire structure of your web app, including directories for models, views, controllers, and configurations.

4. Understanding MVC (Model-View-Controller)

• Model: Represents the data in the application. Rails models communicate with the database, allowing you to store and retrieve data.
• View: The user interface. Views display the data to the user (like HTML templates).
• Controller: Contains the logic that connects the Model and View. It handles user requests, retrieves data from the model, and passes it to the view.

5. Generating a Resource

• Use Rails generators to quickly create resources (models, views, controllers, and routes).
• For example, to create a blog post resource:
  • rails generate scaffold Post title:string body:text
• This command creates everything you need to manage posts, including database migrations, controllers, views, and routes.

6. Migrations and the Database

• Migrations are used to create and modify the database schema.
• After generating resources, run:
  • rails db:migrate
• This updates the database with your models’ new tables or columns.

7. Routing

• Rails uses a file called routes. Rb will define URLs and how they connect to controllers.
• For example, adding resources :posts in the routes file automatically generates routes like /posts, /posts/new, and /posts/:id.

8. Controllers and Actions

• Controllers handle user requests and decide what data to show in views. Each controller action corresponds to a different part of the app.
• Common actions include index (listing all records), show (viewing a single record), new (displaying a form), create (submitting data), edit, and destroy.

9. Views and Templates

• Views are typically written in HTML with embedded Ruby (ERB) to display data. You can use Ruby code in your templates to render dynamic content.
• Each controller action has a corresponding view file (e.g., index.html.erb for the index action).

10. Working with Forms

• Rails makes it easy to create forms that allow users to submit data. Rails helpers automatically generate the HTML for forms, such as form_for to create forms for your models.

11. Rails Console

• The Rails Console is an interactive Ruby shell that works with your app’s data. You can create, read, update, and delete records directly from the command line.

12. Deploying Your App

• Once your app is ready, you can deploy it to platforms like Heroku or other hosting providers. Rails provides easy integration for cloud deployment.