php 52 lines · 7 steps

A single-action JSON user controller in PHP

An invokable controller parses a JSON request, validates it, creates a user, and returns a structured response.

Explained by highlit

Intermediate invokable-class json-api validation dependency-injection constructor-promotion

1<?php
2 
3declare(strict_types=1);
4 
5namespace App\Http;
6 
7final class CreateUserController
8{
9    public function __construct(private readonly UserRepository $users)
10    {
11    }
12 
13    public function __invoke(): void
14    {
15        header('Content-Type: application/json');
16 
17        $raw = file_get_contents('php://input');
18        $payload = json_decode($raw ?: '', true, 512, JSON_THROW_ON_ERROR);
19 
20        if (!is_array($payload) || empty($payload['email']) || empty($payload['name'])) {
21            $this->respond(422, [
22                'error' => 'Validation failed',
23                'fields' => ['email', 'name'],
24            ]);
25            return;
26        }
27 
28        $email = filter_var($payload['email'], FILTER_VALIDATE_EMAIL);
29 
30        if ($email === false) {
31            $this->respond(422, ['error' => 'Invalid email address']);
32            return;
33        }
34 
35        $user = $this->users->create(
36            name: trim((string) $payload['name']),
37            email: $email,
38        );
39 
40        $this->respond(201, [
41            'id' => $user->id,
42            'name' => $user->name,
43            'email' => $user->email,
44        ]);
45    }
46 
47    private function respond(int $status, array $body): void
48    {
49        http_response_code($status);
50        echo json_encode($body, JSON_THROW_ON_ERROR | JSON_UNESCAPED_SLASHES);
51    }
52}

01 / 01

STEP 01

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Three takeaways

1Constructor property promotion collapses dependency injection into a single readonly parameter.
2Validating and normalizing input before persisting keeps bad data out of the repository.
3Centralizing status codes and JSON encoding in one helper keeps every response consistent.

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