Installing Laravel and Defining Routes

Laravel is the most widely used PHP framework for building web applications: it provides routing, controllers, a template engine (Blade), an ORM (Eloquent), validation, queues, testing… This course follows Laravel 13, which requires PHP 8.3 or higher (we use PHP 8.5) and Composer 2.

Creating a project

# With the official installer
composer global require laravel/installer
laravel new boutique        # asks a few questions (starter kit, database, Pest or PHPUnit...)

# Or directly with Composer
composer create-project laravel/laravel boutique

cd boutique
php artisan serve           # http://127.0.0.1:8000
# or: php artisan dev       # server + queue + logs + Vite (also: composer run dev)

By default, a new project uses SQLite (database/database.sqlite, created and migrated at installation): no database server is needed to get started. composer create-project installs PHPUnit for tests; the installer lets you choose between Pest and PHPUnit.

The essential directory structure

Folder / file	Role
routes/web.php	web page routes
app/Http/Controllers	controllers
app/Models	Eloquent models
resources/views	Blade views
database/migrations	schema evolution
bootstrap/app.php	application configuration (middleware, routes, exceptions)
.env	local configuration: database, APP_KEY, debug mode

The .env file contains secrets: it is listed in .gitignore, and it is .env.example that is committed.

First route

// routes/web.php
use Illuminate\Support\Facades\Route;

Route::get('/', function () {
    return view('welcome');           // displays resources/views/welcome.blade.php
});

Route::get('/bonjour', fn () => 'Hello Laravel!'); // a string becomes an HTML response

A route associates an HTTP verb (get, post, put, patch, delete) and a URI with an action.

Parameters and constraints

Route::get('/articles/{id}', function (string $id) {
    return "Article no. $id";
})->whereNumber('id');              // /articles/abc will return 404

Route::get('/auteurs/{nom?}', fn (?string $nom = null) => $nom ?? 'All authors'); // optional parameter

Parameters are injected into the function in the order in which they appear in the URI.

Named routes

Route::get('/articles/{id}', [ArticleController::class, 'show'])->name('articles.show');

// Elsewhere (controller, view):
$url = route('articles.show', ['id' => 42]);   // http://127.0.0.1:8000/articles/42
return redirect()->route('articles.show', ['id' => 42]);

Naming routes lets you change a URI without breaking all the application’s links.

Artisan, your command-line assistant

php artisan route:list          # all routes, their names and actions
php artisan make:controller ArticleController
php artisan tinker              # interactive console

API routes (routes/api.php) are no longer present by default since Laravel 11: you add them with php artisan install:api, which we will see in the advanced course.

In the runnable exercises, you will re-implement the core of a router in plain PHP, to understand what Laravel does for you; the tasks will then have you practice in a real project.