Getting Started with Symfony: ‘Hello World’ Example

Introduction
Prerequisites
Installing Symfony
Setting Up the Web Server
Creating a Controller
Your First Route and Controller
Using Templates
Routes Configuration
Database Connectivity
Conclusion

Introduction

When starting to learn any new framework, it’s always a good practice to begin with a ‘Hello World’ example. This tutorial will guide you through the steps of setting up a basic ‘Hello World’ app using Symfony, one of the leading frameworks for building web applications in PHP.

Prerequisites

PHP 7.2.5 or higher installed on your system
Composer – PHP’s dependency manager
A text editor or IDE of your choice
A basic understanding of PHP

Installing Symfony

Symfony can be easily installed on any platform using Composer:

composer create-project symfony/website-skeleton hello_world

This command creates a new directory called ‘hello_world’ with a basic Symfony project within it.

Setting Up the Web Server

Symfony provides a web server bundle that is super handy for development:

composer require symfony/web-server-bundle --dev

To start the server, navigate to your project directory and run:

php bin/console server:run

Your application will be available at ‘http://localhost:8000’.

Creating a Controller

In Symfony, logic is defined within ‘controllers’. Let’s create a controller to handle our ‘Hello World’ output:

php bin/console make:controller HelloWorldController

This will generate a new controller class and a template for us.

Your First Route and Controller

Open the generated controller located at ‘src/Controller/HelloWorldController.php’ and modify the ‘index’ method:

use Symfony\Component\HttpFoundation\Response;

// ...

public function index(): Response
{
    return new Response('<html><body>Hello World!</body></html>');
}

Visit ‘http://localhost:8000/hello-world’ to see the output.

Using Templates

We can simplify our controller’s action by returning a rendered template:

use Symfony\Component\HttpFoundation\Response;
use Twig\Environment;

// ...

private $twig;

public function __construct(Environment $twig)
{
    $this->twig = $twig;
}

public function index(): Response
{
    return new Response($this->twig->render('hello_world/index.html.twig'));
}

The template file ‘templates/hello_world/index.html.twig’ may look like this:

<html>
    <head><title>Hello World!</title></head>
    <body>
        <h1>Hello World!</h1>
    </body>
</html>

Routes Configuration

Let’s define a route in config/routes.yaml:

hello_world:
    path:  /hello-world
    controller: App\Controller\HelloWorldController::index

This tells Symfony that whenever the ‘/hello-world’ path is hit, it should execute the ‘index’ method on our ‘HelloWorldController’.

Database Connectivity

Although not necessary for a ‘Hello World’ app, it’s useful to know how to connect to a database. This can be achieved by updating the ‘.env’ file with your database credentials and running:

php bin/console doctrine:database:create

This creates a new database that can be used in your Symfony project.

Conclusion

This tutorial provided a step-by-step guide on creating a simple ‘Hello World’ application using Symfony. By following this tutorial, you should now have a basic understanding of Symfony components such as routes, controllers, and views. Keep exploring Symfony’s features to build more complex applications.

Next Article: Symfony Best Practices: Directory Structure and Code Organization

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Series: Symfony & Doctrine Tutotirlas

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