Chris@0: <?php
Chris@0: 
Chris@0: namespace Drupal\Component\Discovery;
Chris@0: 
Chris@0: use Drupal\Component\Serialization\Yaml;
Chris@0: use Drupal\Component\FileCache\FileCacheFactory;
Chris@0: 
Chris@0: /**
Chris@0:  * Provides discovery for YAML files within a given set of directories.
Chris@0:  */
Chris@0: class YamlDiscovery implements DiscoverableInterface {
Chris@0: 
Chris@0:   /**
Chris@0:    * The base filename to look for in each directory.
Chris@0:    *
Chris@0:    * @var string
Chris@0:    */
Chris@0:   protected $name;
Chris@0: 
Chris@0:   /**
Chris@0:    * An array of directories to scan, keyed by the provider.
Chris@0:    *
Chris@0:    * @var array
Chris@0:    */
Chris@0:   protected $directories = [];
Chris@0: 
Chris@0:   /**
Chris@0:    * Constructs a YamlDiscovery object.
Chris@0:    *
Chris@0:    * @param string $name
Chris@0:    *   The base filename to look for in each directory. The format will be
Chris@0:    *   $provider.$name.yml.
Chris@0:    * @param array $directories
Chris@0:    *   An array of directories to scan, keyed by the provider.
Chris@0:    */
Chris@0:   public function __construct($name, array $directories) {
Chris@0:     $this->name = $name;
Chris@0:     $this->directories = $directories;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function findAll() {
Chris@0:     $all = [];
Chris@0: 
Chris@0:     $files = $this->findFiles();
Chris@0:     $provider_by_files = array_flip($files);
Chris@0: 
Chris@0:     $file_cache = FileCacheFactory::get('yaml_discovery:' . $this->name);
Chris@0: 
Chris@0:     // Try to load from the file cache first.
Chris@0:     foreach ($file_cache->getMultiple($files) as $file => $data) {
Chris@0:       $all[$provider_by_files[$file]] = $data;
Chris@0:       unset($provider_by_files[$file]);
Chris@0:     }
Chris@0: 
Chris@0:     // If there are files left that were not returned from the cache, load and
Chris@0:     // parse them now. This list was flipped above and is keyed by filename.
Chris@0:     if ($provider_by_files) {
Chris@0:       foreach ($provider_by_files as $file => $provider) {
Chris@0:         // If a file is empty or its contents are commented out, return an empty
Chris@0:         // array instead of NULL for type consistency.
Chris@0:         $all[$provider] = $this->decode($file);
Chris@0:         $file_cache->set($file, $all[$provider]);
Chris@0:       }
Chris@0:     }
Chris@0: 
Chris@0:     return $all;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Decode a YAML file.
Chris@0:    *
Chris@0:    * @param string $file
Chris@0:    *   Yaml file path.
Chris@0:    * @return array
Chris@0:    */
Chris@0:   protected function decode($file) {
Chris@0:     return Yaml::decode(file_get_contents($file)) ?: [];
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Returns an array of file paths, keyed by provider.
Chris@0:    *
Chris@0:    * @return array
Chris@0:    */
Chris@0:   protected function findFiles() {
Chris@0:     $files = [];
Chris@0:     foreach ($this->directories as $provider => $directory) {
Chris@0:       $file = $directory . '/' . $provider . '.' . $this->name . '.yml';
Chris@0:       if (file_exists($file)) {
Chris@0:         $files[$provider] = $file;
Chris@0:       }
Chris@0:     }
Chris@0:     return $files;
Chris@0:   }
Chris@0: 
Chris@0: }