2.11. Реестр (Registry)

2.11.1. Назначение

Для реализации централизованного хранения объектов, часто используемых во всем приложении, как правило, реализуется с помощью абстрактного класса только c статическими методами (или с помощью шаблона Singleton). Помнте что это вводит глобальное состояние, которого следует избегать. Используйте Dependency Injection вместо Registry.

2.11.2. Диаграмма UML

Alt Registry UML Diagram

2.11.3. Код

Вы можете найти этот код на GitHub

Registry.php

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
<?php declare(strict_types=1);

namespace DesignPatterns\Structural\Registry;

abstract class Registry
{
    const LOGGER = 'logger';

    /**
     * this introduces global state in your application which can not be mocked up for testing
     * and is therefor considered an anti-pattern! Use dependency injection instead!
     *
     * @var Service[]
     */
    private static $services = [];

    /**
     * @var array
     */
    private static $allowedKeys = [
        self::LOGGER,
    ];

    public static function set(string $key, Service $value)
    {
        if (!in_array($key, self::$allowedKeys)) {
            throw new \InvalidArgumentException('Invalid key given');
        }

        self::$services[$key] = $value;
    }

    public static function get(string $key): Service
    {
        if (!in_array($key, self::$allowedKeys) || !isset(self::$services[$key])) {
            throw new \InvalidArgumentException('Invalid key given');
        }

        return self::$services[$key];
    }
}

Service.php

1
2
3
4
5
6
7
8
<?php

namespace DesignPatterns\Structural\Registry;

class Service
{

}

2.11.4. Тест

Tests/RegistryTest.php

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
<?php declare(strict_types=1);

namespace DesignPatterns\Structural\Registry\Tests;

use DesignPatterns\Structural\Registry\Registry;
use DesignPatterns\Structural\Registry\Service;
use PHPUnit\Framework\MockObject\MockObject;
use PHPUnit\Framework\TestCase;

class RegistryTest extends TestCase
{
    private $service;

    protected function setUp(): void
    {
        $this->service = $this->getMockBuilder(Service::class)->getMock();
    }

    public function testSetAndGetLogger()
    {
        /** @noinspection PhpParamsInspection */
        Registry::set(Registry::LOGGER, $this->service);

        $this->assertSame($this->service, Registry::get(Registry::LOGGER));
    }

    public function testThrowsExceptionWhenTryingToSetInvalidKey()
    {
        $this->expectException(\InvalidArgumentException::class);

        Registry::set('foobar', $this->service);
    }

    /**
     * notice @runInSeparateProcess here: without it, a previous test might have set it already and
     * testing would not be possible. That's why you should implement Dependency Injection where an
     * injected class may easily be replaced by a mockup
     *
     * @runInSeparateProcess
     */
    public function testThrowsExceptionWhenTryingToGetNotSetKey()
    {
        $this->expectException(\InvalidArgumentException::class);

        Registry::get(Registry::LOGGER);
    }
}