IniFileLoader example

        $cacheDir = $container->getParameter('kernel.cache_dir');
        if (!\is_string($cacheDir)) {
            throw new \RuntimeException('Container parameter "kernel.cache_dir" needs to be a string');
        }

        $locator = new FileLocator('Resources/config');

        $resolver = new LoaderResolver([
            new XmlFileLoader($container, $locator),
            new YamlFileLoader($container, $locator),
            new IniFileLoader($container, $locator),
            new PhpFileLoader($container, $locator),
            new GlobFileLoader($container, $locator),
            new DirectoryLoader($container, $locator),
            new ClosureLoader($container),
        ]);

        $configLoader = new DelegatingLoader($resolver);

        $confDir = $this->getPath() . '/Resources/config';

        $configLoader->load($confDir . '/{packages}/*' . Kernel::CONFIG_EXTS, 'glob');
        

$container->addCompilerPass(new ReverseProxyCompilerPass());
        $container->addCompilerPass(new StorefrontMigrationReplacementCompilerPass());
    }

    private function buildConfig(ContainerBuilder $container, string $environment): void
    {
        $locator = new FileLocator('Resources/config');

        $resolver = new LoaderResolver([
            new XmlFileLoader($container, $locator),
            new YamlFileLoader($container, $locator),
            new IniFileLoader($container, $locator),
            new PhpFileLoader($container, $locator),
            new GlobFileLoader($container, $locator),
            new DirectoryLoader($container, $locator),
            new ClosureLoader($container),
        ]);

        $configLoader = new DelegatingLoader($resolver);

        $confDir = $this->getPath() . '/Resources/config';

        $configLoader->load($confDir . '/{packages}/*' . Kernel::CONFIG_EXTS, 'glob');
        

        return new ElasticsearchExtension();
    }

    private function buildConfig(ContainerBuilder $container): void
    {
        $locator = new FileLocator('Resources/config');

        $resolver = new LoaderResolver([
            new XmlFileLoader($container, $locator),
            new YamlFileLoader($container, $locator),
            new IniFileLoader($container, $locator),
            new PhpFileLoader($container, $locator),
            new GlobFileLoader($container, $locator),
            new DirectoryLoader($container, $locator),
            new ClosureLoader($container),
        ]);

        $configLoader = new DelegatingLoader($resolver);

        $confDir = $this->getPath() . '/Resources/config';

        $configLoader->load($confDir . '/{packages}/*' . Kernel::CONFIG_EXTS, 'glob');