Nette DI service collections

ServiceCollectionsExtension.php

<?php

declare(strict_types=1);

namespace App;

use Nette\DI\CompilerExtension;


/**
 * Nette DI extension (https://nette.org/).
 *
 * Creates collections of services in DI container. Usage in NEON:
 *     extensions:
 *         serviceCollections: App\ServiceCollectionsExtension
 *
 *     serviceCollections:
 *         - MyInterfaceCollection
 *         - OtherClassCollection
 *
 * With such configuration, two new services of MyInterfaceCollection and OtherClassCollection type are created.
 * By convention, they must declare add() method with one typed parameter. A type of this parameter is taken and
 * every service from DI container of the type is passed to add() method in setup phase.
 */
class ServiceCollectionsExtension extends CompilerExtension
{
	private const METHOD = 'add';

	/** @var string[] */
	private $services = [];


	public function loadConfiguration()
	{
		$config = $this->getConfig();
		$builder = $this->getContainerBuilder();

		foreach ($config as $key => $class) {
			if (!class_exists($class)) {
				throw new \LogicException("Cannot create service collection. Collection class '$class' does not exist.");
			}

			$rc = new \ReflectionClass($class);
			if (!$rc->hasMethod(self::METHOD)) {
				throw new \LogicException("Cannot create service collection. Missing '$class::" . self::METHOD . "()' method.");
			}

			$params = $rc->getMethod(self::METHOD)->getParameters();
			if (count($params) !== 1) {
				throw new \LogicException("Cannot create service collection. Method '$class::" . self::METHOD . "()' must have exactly one parameter, but has " . count($params) . '.');

			} elseif (!$params[0]->hasType()) {
				throw new \LogicException("Cannot create service collection. Missing type of '$class::" . self::METHOD . "(\${$params[0]->getName()})' parameter.");

			} elseif ($params[0]->getType()->isBuiltin()) {
				throw new \LogicException("Cannot create service collection. Parameter '$class::" . self::METHOD . "(\${$params[0]->getName()})' has builtin type. It is not supported.");
			}

			$type = $params[0]->getType()->getName();
			$builder
				->addDefinition($name = $this->prefix($key))
				->setFactory($class);

			$this->services[$name] = $type;
		}
	}


	public function beforeCompile()
	{
		$builder = $this->getContainerBuilder();
		foreach ($this->services as $name => $type) {
			$service = $builder->getDefinition($name);
			foreach ($builder->findByType($type) as $add) {
				$service->addSetup(self::METHOD, [$add]);
			}
		}
	}
}