class YamlFileLoader

1. 9.x drupal/core/vendor/symfony/routing/Symfony/Component/Routing/Loader/YamlFileLoader.php \Symfony\Component\Routing\Loader\YamlFileLoader
2. 9.x drupal/core/vendor/symfony/dependency-injection/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php \Symfony\Component\DependencyInjection\Loader\YamlFileLoader

Kernel.php in drupal/core/vendor/symfony/http-kernel/Symfony/Component/HttpKernel/Kernel.php

XmlFileLoaderTest.php in drupal/core/vendor/symfony/dependency-injection/Symfony/Component/DependencyInjection/Tests/Loader/XmlFileLoaderTest.php

YamlFileLoaderTest.php in drupal/core/vendor/symfony/dependency-injection/Symfony/Component/DependencyInjection/Tests/Loader/YamlFileLoaderTest.php

class YamlFileLoader extends FileLoader {

  /**
   * Loads a Yaml file.
   *
   * @param mixed  $file The resource
   * @param string $type The resource type
   */
  public function load($file, $type = null) {
    $path = $this->locator
      ->locate($file);
    $content = $this
      ->loadFile($path);
    $this->container
      ->addResource(new FileResource($path));

    // empty file
    if (null === $content) {
      return;
    }

    // imports
    $this
      ->parseImports($content, $file);

    // parameters
    if (isset($content['parameters'])) {
      foreach ($content['parameters'] as $key => $value) {
        $this->container
          ->setParameter($key, $this
          ->resolveServices($value));
      }
    }

    // extensions
    $this
      ->loadFromExtensions($content);

    // services
    $this
      ->parseDefinitions($content, $file);
  }

  /**
   * Returns true if this class supports the given resource.
   *
   * @param mixed  $resource A resource
   * @param string $type     The resource type
   *
   * @return Boolean true if this class supports the given resource, false otherwise
   */
  public function supports($resource, $type = null) {
    return is_string($resource) && 'yml' === pathinfo($resource, PATHINFO_EXTENSION);
  }

  /**
   * Parses all imports
   *
   * @param array  $content
   * @param string $file
   */
  private function parseImports($content, $file) {
    if (!isset($content['imports'])) {
      return;
    }
    foreach ($content['imports'] as $import) {
      $this
        ->setCurrentDir(dirname($file));
      $this
        ->import($import['resource'], null, isset($import['ignore_errors']) ? (bool) $import['ignore_errors'] : false, $file);
    }
  }

  /**
   * Parses definitions
   *
   * @param array  $content
   * @param string $file
   */
  private function parseDefinitions($content, $file) {
    if (!isset($content['services'])) {
      return;
    }
    foreach ($content['services'] as $id => $service) {
      $this
        ->parseDefinition($id, $service, $file);
    }
  }

  /**
   * Parses a definition.
   *
   * @param string $id
   * @param array  $service
   * @param string $file
   */
  private function parseDefinition($id, $service, $file) {
    if (is_string($service) && 0 === strpos($service, '@')) {
      $this->container
        ->setAlias($id, substr($service, 1));
      return;
    }
    elseif (isset($service['alias'])) {
      $public = !array_key_exists('public', $service) || (bool) $service['public'];
      $this->container
        ->setAlias($id, new Alias($service['alias'], $public));
      return;
    }
    if (isset($service['parent'])) {
      $definition = new DefinitionDecorator($service['parent']);
    }
    else {
      $definition = new Definition();
    }
    if (isset($service['class'])) {
      $definition
        ->setClass($service['class']);
    }
    if (isset($service['scope'])) {
      $definition
        ->setScope($service['scope']);
    }
    if (isset($service['synthetic'])) {
      $definition
        ->setSynthetic($service['synthetic']);
    }
    if (isset($service['public'])) {
      $definition
        ->setPublic($service['public']);
    }
    if (isset($service['abstract'])) {
      $definition
        ->setAbstract($service['abstract']);
    }
    if (isset($service['factory_class'])) {
      $definition
        ->setFactoryClass($service['factory_class']);
    }
    if (isset($service['factory_method'])) {
      $definition
        ->setFactoryMethod($service['factory_method']);
    }
    if (isset($service['factory_service'])) {
      $definition
        ->setFactoryService($service['factory_service']);
    }
    if (isset($service['file'])) {
      $definition
        ->setFile($service['file']);
    }
    if (isset($service['arguments'])) {
      $definition
        ->setArguments($this
        ->resolveServices($service['arguments']));
    }
    if (isset($service['properties'])) {
      $definition
        ->setProperties($this
        ->resolveServices($service['properties']));
    }
    if (isset($service['configurator'])) {
      if (is_string($service['configurator'])) {
        $definition
          ->setConfigurator($service['configurator']);
      }
      else {
        $definition
          ->setConfigurator(array(
          $this
            ->resolveServices($service['configurator'][0]),
          $service['configurator'][1],
        ));
      }
    }
    if (isset($service['calls'])) {
      foreach ($service['calls'] as $call) {
        $args = isset($call[1]) ? $this
          ->resolveServices($call[1]) : array();
        $definition
          ->addMethodCall($call[0], $args);
      }
    }
    if (isset($service['tags'])) {
      if (!is_array($service['tags'])) {
        throw new InvalidArgumentException(sprintf('Parameter "tags" must be an array for service "%s" in %s.', $id, $file));
      }
      foreach ($service['tags'] as $tag) {
        if (!isset($tag['name'])) {
          throw new InvalidArgumentException(sprintf('A "tags" entry is missing a "name" key for service "%s" in %s.', $id, $file));
        }
        $name = $tag['name'];
        unset($tag['name']);
        foreach ($tag as $attribute => $value) {
          if (!is_scalar($value)) {
            throw new InvalidArgumentException(sprintf('A "tags" attribute must be of a scalar-type for service "%s", tag "%s" in %s.', $id, $name, $file));
          }
        }
        $definition
          ->addTag($name, $tag);
      }
    }
    $this->container
      ->setDefinition($id, $definition);
  }

  /**
   * Loads a YAML file.
   *
   * @param string $file
   *
   * @return array The file content
   */
  private function loadFile($file) {
    return $this
      ->validate(Yaml::parse($file), $file);
  }

  /**
   * Validates a YAML file.
   *
   * @param mixed  $content
   * @param string $file
   *
   * @return array
   *
   * @throws InvalidArgumentException When service file is not valid
   */
  private function validate($content, $file) {
    if (null === $content) {
      return $content;
    }
    if (!is_array($content)) {
      throw new InvalidArgumentException(sprintf('The service file "%s" is not valid.', $file));
    }
    foreach (array_keys($content) as $namespace) {
      if (in_array($namespace, array(
        'imports',
        'parameters',
        'services',
      ))) {
        continue;
      }
      if (!$this->container
        ->hasExtension($namespace)) {
        $extensionNamespaces = array_filter(array_map(function ($ext) {
          return $ext
            ->getAlias();
        }, $this->container
          ->getExtensions()));
        throw new InvalidArgumentException(sprintf('There is no extension able to load the configuration for "%s" (in %s). Looked for namespace "%s", found %s', $namespace, $file, $namespace, $extensionNamespaces ? sprintf('"%s"', implode('", "', $extensionNamespaces)) : 'none'));
      }
    }
    return $content;
  }

  /**
   * Resolves services.
   *
   * @param string $value
   *
   * @return Reference
   */
  private function resolveServices($value) {
    if (is_array($value)) {
      $value = array_map(array(
        $this,
        'resolveServices',
      ), $value);
    }
    elseif (is_string($value) && 0 === strpos($value, '@')) {
      if (0 === strpos($value, '@?')) {
        $value = substr($value, 2);
        $invalidBehavior = ContainerInterface::IGNORE_ON_INVALID_REFERENCE;
      }
      else {
        $value = substr($value, 1);
        $invalidBehavior = ContainerInterface::EXCEPTION_ON_INVALID_REFERENCE;
      }
      if ('=' === substr($value, -1)) {
        $value = substr($value, 0, -1);
        $strict = false;
      }
      else {
        $strict = true;
      }
      $value = new Reference($value, $invalidBehavior, $strict);
    }
    return $value;
  }

  /**
   * Loads from Extensions
   *
   * @param array $content
   */
  private function loadFromExtensions($content) {
    foreach ($content as $namespace => $values) {
      if (in_array($namespace, array(
        'imports',
        'parameters',
        'services',
      ))) {
        continue;
      }
      if (!is_array($values)) {
        $values = array();
      }
      $this->container
        ->loadFromExtension($namespace, $values);
    }
  }

}