Dependency Injection For Function Example

DependencyInjectionForFuncExample.php

<?php

/*
 * # installation
 *
 * $ cat composer.json
 * {
 *   "require": {
 *       "pimple/pimple": "~3.0"
 *   }
 * }
 * $ composer install
 */

namespace Dcb9 {
	interface SessionInterface {
		public function getStorage();
	}
}

namespace {
	require_once './vendor/autoload.php';

	use Pimple\Container;

	class SessionStorage {}
	class Session implements Dcb9\SessionInterface {
		protected $storage;

		public function __construct($storage) {
			$this->storage = $storage;
		}

		public function getStorage()
		{
			return $this->storage;
		}
	}

	$container = new Container();
	$container['session_storage'] = function ($c) {
		return new SessionStorage();
	};
	$container['session'] = function ($c) {
		return new Session($c['session_storage']);
	};

	$testFunc = function ($name, Dcb9\SessionInterface $session) {
		var_dump($session);
		var_dump($name);
	};

	$refFunc = new ReflectionFunction($testFunc);
	$args = [];
	foreach ($refFunc->getParameters() as $param) {
		$type = $param->getType();
		$value = null;
		if ($type === null && $param->name == 'name') {
			 $value = 'bob';
		} else {
			$className = $type->__toString();
			if($container['session'] instanceof $className) {
				$value = $container['session'];
			}
		}

		$args[$param->getPosition()] = $value;
	}

	$refFunc->invokeArgs($args);
}