RegisterStreamWrappersPass.php

<?php

namespace Drupal\Core\DependencyInjection\Compiler;

use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
use Symfony\Component\DependencyInjection\Compiler\ServiceLocatorTagPass;
use Symfony\Component\DependencyInjection\ContainerBuilder;
use Symfony\Component\DependencyInjection\Reference;

/**
 * Adds services tagged 'stream_wrapper' to the stream_wrapper_manager service.
 */
class RegisterStreamWrappersPass implements CompilerPassInterface {
    
    /**
     * {@inheritdoc}
     */
    public function process(ContainerBuilder $container) : void {
        if (!$container->hasDefinition('stream_wrapper_manager')) {
            return;
        }
        $stream_wrapper_manager = $container->getDefinition('stream_wrapper_manager');
        $services = [];
        foreach ($container->findTaggedServiceIds('stream_wrapper') as $id => $tags) {
            $class = $container->getDefinition($id)
                ->getClass();
            // Loop through all the tags for this stream wrapper as we may have
            // multiple schemes.
            foreach ($tags as $attributes) {
                $stream_wrapper_manager->addMethodCall('addStreamWrapper', [
                    $id,
                    $class,
                    $attributes['scheme'],
                ]);
            }
            $services[$id] = new Reference($id);
        }
        $stream_wrapper_manager->addArgument(ServiceLocatorTagPass::register($container, $services));
    }

}