<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Contracts\Service;
use Psr\Container\ContainerExceptionInterface;
use Psr\Container\NotFoundExceptionInterface;
// Help opcache.preload discover always-needed symbols
class_exists(ContainerExceptionInterface::class);
class_exists(NotFoundExceptionInterface::class);
/**
* A trait to help implement ServiceProviderInterface.
*
* @author Robin Chalas <robin.chalas@gmail.com>
* @author Nicolas Grekas <p@tchwork.com>
*/
trait ServiceLocatorTrait
{
private $factories;
private $loading = [];
private $providedTypes;
/**
* @param callable[] $factories
*/
public function __construct(array $factories)
{
$this->factories = $factories;
}
/**
* {@inheritdoc}
*
* @return bool
*/
public function has($id)
{
return isset($this->factories[$id]);
}
/**
* {@inheritdoc}
*/
public function get($id)
{
if (!isset($this->factories[$id])) {
throw $this->createNotFoundException($id);
}
if (isset($this->loading[$id])) {
$ids = array_values($this->loading);
$ids = \array_slice($this->loading, array_search($id, $ids));
$ids[] = $id;
throw $this->createCircularReferenceException($id, $ids);
}
$this->loading[$id] = $id;
try {
return $this->factories[$id]($this);
} finally {
unset($this->loading[$id]);
}
}
/**
* {@inheritdoc}
*/
public function getProvidedServices(): array
{
if (null === $this->providedTypes) {
$this->providedTypes = [];
foreach ($this->factories as $name => $factory) {
if (!\is_callable($factory)) {
$this->providedTypes[$name] = '?';
} else {
$type = (new \ReflectionFunction($factory))->getReturnType();
$this->providedTypes[$name] = $type ? ($type->allowsNull() ? '?' : '').($type instanceof \ReflectionNamedType ? $type->getName() : $type) : '?';
}
}
}
return $this->providedTypes;
}
private function createNotFoundException(string $id): NotFoundExceptionInterface
{
if (!$alternatives = array_keys($this->factories)) {
$message = 'is empty...';
} else {
$last = array_pop($alternatives);
if ($alternatives) {
$message = sprintf('only knows about the "%s" and "%s" services.', implode('", "', $alternatives), $last);
} else {
$message = sprintf('only knows about the "%s" service.', $last);
}
}
if ($this->loading) {
$message = sprintf('The service "%s" has a dependency on a non-existent service "%s". This locator %s', end($this->loading), $id, $message);
} else {
$message = sprintf('Service "%s" not found: the current service locator %s', $id, $message);
}
return new class($message) extends \InvalidArgumentException implements NotFoundExceptionInterface {
};
}
private function createCircularReferenceException(string $id, array $path): ContainerExceptionInterface
{
return new class(sprintf('Circular reference detected for service "%s", path: "%s".', $id, implode(' -> ', $path))) extends \RuntimeException implements ContainerExceptionInterface {
};
}
}