Controllers

In NixPHP, a controller is anything that handles an incoming HTTP request.
This can be either:

• a controller class method, or
• an anonymous function (Closure).

This section explains both options.

Controller Classes

You can define a controller as a simple PHP class with public methods.

namespace App\Controllers;

use function NixPHP\render;

class HelloController
{
    public function index()
    {
        return render('hello', ['name' => 'World']);
    }
}

• Namespace: Controllers are typically placed in App\Controllers.
• Method: The method name should match the one you defined in your route.
• Return: The method must return a Psr\Http\Message\ResponseInterface.

Defining a Route to a Controller

// app/routes.php

route()->add('GET', '/hello', [HelloController::class, 'index']);

When a user visits /hello, NixPHP:

1. Instantiates the HelloController.
2. Calls the index() method.
3. Sends the returned Response to the browser.

Closures as Controllers

Instead of using a class, you can define a route directly with a Closure:

// app/routes.php

use function NixPHP\response;

route()->add('GET', '/ping', function () {
    return response('Pong!');
});

• Closures must also return a Psr\Http\Message\ResponseInterface.
• Useful for small endpoints, quick APIs, or simple prototyping.

Route Parameters

If your route contains dynamic segments, NixPHP passes them automatically to your handler:

// app/routes.php

route()->add('GET', '/user/{id}', [UserController::class, 'profile']);

Controller example:

namespace App\Controllers;

use function NixPHP\render;

class UserController
{
    public function profile($id)
    {
        return render('user-profile', ['id' => $id]);
    }
}

Closure example:

route()->add('GET', '/order/{orderId}', function ($orderId) {
    return response("Order ID: {$orderId}");
});

• Parameters are injected based on their order.
• Parameter names in methods or closures do not have to match the URL placeholders — only the position matters.

Returning Responses

Every handler (whether class method or closure) must return a Psr\Http\Message\ResponseInterface.

Helper functions available:

Helper	Description
render($template, $variables = [])	Renders a view and returns an HTML Response
response($content)	Creates a basic text response

When to use Controller Classes vs. Closures

Use Case	Recommended Approach
Larger, structured application logic	Controller class
Handling multiple related routes (e.g., UserController, PostController)	Controller class
Small, isolated endpoints	Closure
Quick API prototypes or testing	Closure
You want to group logic and share methods	Controller class
You just need a quick one-off response	Closure