Ruby on Rails, often simply referred to as Rails, is a popular web application framework that helps developers quickly build web applications with less code. In this blog post, we will explore what Rails is, why it's so popular, and how to get started with it. We'll be using real code examples and analogies to help you understand the concepts, so even if you're new to programming, you'll be able to follow along.
What is Ruby on Rails?
Rails is a web application framework built on top of the Ruby programming language. A web application framework is like a toolbox for developers, providing them with the tools and components they need to build web applications more efficiently. Ruby is an object-oriented programming language designed to be easy to read and write. Rails combines the best parts of Ruby with a set of conventions and best practices to help developers write clean, maintainable code.
To better understand what Rails is, let's use an analogy. Imagine you're building a house. You could start from scratch, cutting down trees and milling your own lumber, but that would be a lot of work. Instead, you might choose to use pre-built components like wall frames, windows, and doors. These components save you time and effort, allowing you to focus on the overall design and structure of the house.
Rails is like those pre-built components for web applications. It provides a structure and conventions that developers can follow to quickly build web applications without having to reinvent the wheel each time.
Why is Rails popular?
Rails has gained popularity for several reasons. Some of the key factors include:
Convention over configuration: Rails follows a set of conventions that help developers write clean, maintainable code. These conventions also reduce the amount of configuration required to set up a new application, allowing developers to focus on writing code rather than configuring their environment.
Don't Repeat Yourself (DRY): Rails encourages developers to write code that is reusable and modular, reducing the amount of duplicated code in a project. This makes the code easier to maintain and update.
Rapid development: Rails provides many tools and shortcuts that help developers build web applications quickly. These include code generators, a built-in development server, and a powerful database integration system called ActiveRecord.
Active community: Rails has a large and active community of developers who contribute to the project, create third-party libraries (called "gems"), and help answer questions on forums like Stack Overflow.
Wide adoption: Rails has been used to build many popular websites, including GitHub, Shopify, and Airbnb. This means that there are plenty of resources and examples available to help you learn and grow as a Rails developer.
Getting started with Rails
To get started with Rails, you'll first need to install Ruby and Rails on your computer. You can find instructions for your specific operating system on the official Rails installation guide.
Once you have Ruby and Rails installed, you can create a new Rails application by running the following command in your terminal:
rails new my_first_rails_app
This will create a new directory called
my_first_rails_app with the basic structure of a Rails application. You can replace "my_first_rails_app" with any name you choose.
Next, navigate to the newly created directory by running:
Now that you're inside the Rails application directory, you can start the built-in development server by running:
This will start the server on port 3000 by default. Open your web browser and navigate to
http://localhost:3000, and you should see the "Welcome aboard" Rails page.
Congratulations! You've just created your first Rails application.
Understanding the Rails structure
Rails follows a specific structure called the Model-View-Controller (MVC) pattern. This pattern separates the application into three main components:
Model: Represents the data and business logic of the application. Models interact with the database and perform operations like creating, updating, and fetching records.
View: Represents the presentation layer of the application. Views display the data from the model in a user-friendly format, such as an HTML page.
Controller: Acts as an intermediary between the model and the view. Controllers receive user input from the view, process that input, and update the model and/or view accordingly.
To illustrate how these components work together, let's create a simple Rails application that manages a list of tasks.
First, we'll generate a new model called
Task by running the following command:
rails generate model Task title:string completed:boolean
This command creates a new model called
Task with two attributes:
title (a string) and
completed (a boolean). It also generates a database migration file, which is used to create the tasks table in the database.
Next, run the following command to apply the migration and create the tasks table:
Now that we have our model set up, let's create a controller to handle user input. Run the following command to generate a new controller called
rails generate controller Tasks
This command creates a new file called
tasks_controller.rb inside the
app/controllers directory. Open this file and add the following code to create a new action called
class TasksController < ApplicationController def index @tasks = Task.all end end
index action fetches all tasks from the database and stores them in an instance variable called
@tasks. Instance variables are available to the view, so we can use
@tasks to display the list of tasks in the browser.
Next, let's create a view for the
index action. Create a new file called
index.html.erb inside the
app/views/tasks directory and add the following code:
<h1>Task List</h1> <table> <thead> <tr> <th>Title</th> <th>Completed</th> </tr> </thead> <tbody> <% @tasks.each do |task| %> <tr> <td><%= task.title %></td> <td><%= task.completed ? 'Yes' : 'No' %></td> </tr> <% end %> </tbody> </table>
This code creates an HTML table and uses a loop to display each task's title and completed status.
Finally, we need to update the routes file to tell Rails to use our new controller and action. Open the file
config/routes.rb and add the following line:
This line creates a set of routes for the
TasksController, including the
index action we just created.
Restart your Rails server and navigate to
http://localhost:3000/tasks, and you should see the task list with an empty table. You've just created a simple Rails application that follows the MVC pattern!
In this blog post, we've introduced Ruby on Rails, explained its popularity, and walked through creating a simple Rails application. Rails provides a powerful set of tools and conventions that enable developers to build web applications quickly and efficiently.
As you continue learning Rails, you'll discover many more features and techniques to help you build complex, feature-rich applications. The Rails community is a valuable resource for learning and growing as a developer, so don't hesitate to ask questions and seek help when needed. Good luck on your Rails journey!