What Happens When You Run “php artisan serve” in Laravel?

Laravel is one of the most popular PHP frameworks, making web development efficient and enjoyable. As a developer, you’ve likely used the php artisan serve command to quickly start a local development server. But have you ever wondered what happens behind the scenes when you run this command? Let’s explore this in detail, step by step, understand how Laravel identifies and runs the ServeCommand, and dive into what PHP’s built-in server is and how it compares to traditional web servers like Nginx or Apache.

What is php artisan serve?

The php artisan serve command is a Laravel feature that starts a local web server for your project. It uses PHP’s built-in server to make your Laravel application accessible at a specific address (e.g., http://127.0.0.1:8000) during development.

This command is especially useful for local development because it doesn’t require setting up a full-fledged web server like Nginx or Apache.

Step-by-Step Process: What Happens When You Run php artisan serve?

1. User Runs the Command
When you type php artisan serve in the terminal, Laravel's Artisan Console a command line tool for Laravel, kicks into action. It’s like a toolbox with various commands to assist in building, testing, and running Laravel applications.

2. Artisan Entry Point

• The artisan file in your project’s root directory acts as the entry point for all Artisan commands.
• When you run php artisan serve, the artisan file does the following:

1. Includes Composer’s autoloader (vendor/autoload.php).
2. Bootstraps the Laravel framework using bootstrap/app.php.

3. Artisan Finds the ServeCommand

• Laravel registers all Artisan commands when the application boots. For built-in commands like serve, Laravel registers them in the Illuminate\Foundation\Providers\ArtisanServiceProvider.
• This provider maps the command name (serve) to its corresponding class (Illuminate\Foundation\Console\ServeCommand).

4. Command Resolution and Autoloading

• The ServeCommand is located in the vendor/laravel/framework directory under the namespace Illuminate\Foundation\Console.
• Laravel uses Composer’s PSR-4 autoloading configuration to locate and load the class.
• This allows the ServeCommand class to be loaded without the full Laravel framework being fully initialized yet.

5. Preparing the Server

• The ServeCommand configures the PHP built-in server:
• Host: Default is 127.0.0.1 (localhost).
• Port: Default is 8000 (or a custom one via --port option).
• Document Root: Points to the public directory where Laravel’s entry file (index.php) resides.
• Internally, the command executes:

php -S 127.0.0.1:8000 -t public server.php

• php -S Starts PHP’s built-in server.
• -t public Specifies the document root.
• server.php: A router file to handle dynamic requests.

6. Handling Requests

• The server.php file acts as a router:
• If the requested file (e.g., CSS, JS) exists, it is served directly.
• Otherwise, requests are forwarded to index.php.

7. Laravel Processes the Request

• The index.php file initializes Laravel’s framework and handles incoming HTTP requests.
• It routes the request to the appropriate controller, processes the logic, and generates a response (e.g., HTML or JSON).

8. Response is Sent Back

The Laravel response is sent back to the PHP built-in server, which then delivers it to the browser.

What is PHP’s Built-In Server?

PHP’s built-in server is a simple development server introduced in PHP 5.4. It’s designed to help developers test applications without needing to install or configure a full web server.

Features of PHP Built-In Server:

• Ease of Use: Start it with a single command (php -S).
• Dynamic and Static Files: Serves both PHP scripts and static files like images or stylesheets.
• Custom Routing: Allows custom handling of requests through a router script (like Laravel’s server.php).

Comparison: PHP Built-In Server vs. Nginx/Apache

• Purpose: The PHP Built-in Server is For Development purposes only. Nginx/Apache is for both Production-ready and development.
• Performance: The PHP built-in server is Single-threaded (one request at a time) and Nginx/Apache is Multi-threaded (handles many requests concurrently)
• Configuration: The PHP built-in server minimal setup requires. nginx/Apache needs configuration files.
• Advanced Features: The PHP built-in server is Limited (e.g., no caching). Nignx/Apache can be used for Caching, load balancing, and more.

While this setup is convenient, it’s meant only for development. For live applications, web servers like Nginx or Apache provide the scalability and performance necessary for handling production traffic.

P.S. It always interests me to learn how things work behind the scenes. This helps me understand what is actually happening when I am building an application. You can read my other articles.