How To Build A Simple CRUD App With Ruby On Rails

Ruby on Rails, commonly referred to as Rails, is a popular web application framework written in the Ruby programming language. It follows the Model-View-Controller (MVC) architectural pattern and is known for its “convention over configuration” philosophy, which minimizes the amount of code needed to get a web application up and running.

In this blog, we will guide you through building a simple CRUD (Create, Read, Update, Delete) application with Ruby on Rails.

Prerequisites To follow along with this tutorial, you will need:

Ruby installed on your system

RubyGems, the Ruby package manager

Rails, which can be installed using RubyGems

A database management system (DBMS) such as MySQL or PostgreSQL

Step 1: Create a New Rails Application

Open up your terminal or command prompt and create a new Rails application using the following command:

rails new crud_app

This command will create a new directory called “crud_app” in your current directory and generate all the necessary files and folders for a new Rails application.

Step 2: Generate a Model and Migration

In Rails, models are used to represent data in the database. To generate a new model, run the following command:

rails generate model Product name:string description:text price:decimal

This command generates a new model called “Product” with three attributes: name, description, and price. The “name” attribute is a string, “description” is text, and “price” is a decimal number.

Rails also generates a migration file that defines how the table should be created in the database. To run the migration, use the following command:

rails db:migrate

This will create a new table in the database called “products” with the columns we specified in our migration.

Step 3: Generate a Controller

Controllers in Rails handle the logic for handling requests and rendering views. To generate a new controller, run the following command:

rails generate controller Products

This command generates a new controller called “Products”. By default, Rails will create a new directory called “products” inside the “app/views” directory, which will contain all the view templates for the Products controller.

Step 4: Add Routes

Routes in Rails determine which controller action should be called when a particular URL is requested. To add a route for our Products controller, open up the “config/routes.rb” file and add the following line:

resources :products

This line tells Rails to generate all the necessary routes for a RESTful resource called “products”, including routes for creating, reading, updating, and deleting products.

Step 5: Implement CRUD Functionality

Now that we have our model, controller, and routes set up, we can start implementing the CRUD functionality for our Products. Open up the “app/controllers/products_controller.rb” file and add the following actions:

index: This action retrieves all the products from the database and renders a view that displays them.

show: This action retrieves a single product based on its ID and renders a view that displays it.

new: This action initializes a new product object and renders a view that displays a form for creating a new product.

create: This action creates a new product object based on the parameters submitted from the new form and saves it to the database.

edit: This action retrieves a single product based on its ID and renders a view that displays a form for editing it.

update: This action updates an existing product based on the parameters submitted from the edit form.

destroy: This action deletes an existing product based on its ID.

Conclusion