DDST-819: Rework stream wrapper away from "local"

src/StreamWrapper/Foxml.php

@@ -3,16 +3,17 @@
 namespace Drupal\foxml\StreamWrapper;
 
 use Drupal\Core\File\FileSystem;
-use Drupal\Core\StreamWrapper\LocalReadOnlyStream;
+use Drupal\Core\StreamWrapper\ReadOnlyStream;
+use Drupal\Core\StreamWrapper\StreamWrapperInterface;
 use Drupal\Core\Url;
-
 use Drupal\foxml\Utility\Fedora3\DatastreamLowLevelAdapterInterface;
 use Drupal\foxml\Utility\Fedora3\ObjectLowLevelAdapterInterface;
+use Psr\Log\LoggerInterface;
 
 /**
  * FOXML stream wrapper.
  */
-class Foxml extends LocalReadOnlyStream {
+class Foxml extends ReadOnlyStream {
 
   use NotWritableTrait;
 
@@ -37,6 +38,13 @@ class Foxml extends LocalReadOnlyStream {
    */
   protected FileSystem $fileSystem;
 
+  /**
+   * Logging channel.
+   *
+   * @var \Psr\Log\LoggerInterface
+   */
+  protected LoggerInterface $logger;
+
   /**
    * Constructor.
    *
@@ -49,18 +57,12 @@ public function __construct() {
     $this->datastreamAdapter = \Drupal::service('foxml.parser.datastream_lowlevel_storage');
     $this->objectAdapter = \Drupal::service('foxml.parser.object_lowlevel_storage');
     $this->fileSystem = \Drupal::service('file_system');
+    $this->logger = \Drupal::service('logger.channel.foxml');
     // phpcs:enable
   }
 
   /**
-   * {@inheritdoc}
-   */
-  public function getDirectoryPath() {
-    throw new \Exception('Overides ::getLocalPath(), so this is not necessary.');
-  }
-
-  /**
-   * {@inheritdoc}
+   * {@inheritDoc}
    */
   protected function getLocalPath($uri = NULL) {
     // XXX: Adapted from LocalReadOnlyStream::getLocalPath().
@@ -75,14 +77,26 @@ protected function getLocalPath($uri = NULL) {
       return FALSE;
     }
     [$subtype, $target_actual] = $exploded;
+    // XXX: If you see this assert() complaining about "styles", you need some
+    // form of image style remapping, to have image style derivatives to be
+    // created under a different, writeable scheme.
     assert(in_array($subtype, ['object', 'datastream']), 'Valid URI.');
 
     try {
-      $path = $this->{"{$subtype}Adapter"}->dereference($target_actual);
+      /** @var \Drupal\foxml\Utility\Fedora3\LowLevelAdapterInterface $adapter */
+      $adapter = match($subtype) {
+        'object' => $this->objectAdapter,
+        'datastream' => $this->datastreamAdapter,
+      };
+      $path = $adapter->dereference($target_actual);
       assert(is_string($path), 'Dereferenced path.');
     }
     catch (\Exception $e) {
-      trigger_error('Failed to dereference URI.', E_USER_WARNING);
+      $this->logger->warning('Failed to dereference URI "{uri}". Exception info: {message}, {trace}', [
+        'uri' => $uri,
+        'message' => $e->getMessage(),
+        'trace' => $e->getTraceAsString(),
+      ]);
       return FALSE;
     }
 
@@ -110,8 +124,7 @@ protected function getLocalPath($uri = NULL) {
   public function getExternalUrl() {
     // XXX: Copypasta from
     // \Drupal\Core\StreamWrapper\PrivateStream::getExternalUrl().
-    $path = str_replace('\\', '/', $this
-      ->getTarget());
+    $path = str_replace('\\', '/', $this->getTarget());
     return Url::fromRoute('foxml.download', [
       'filepath' => $path,
     ], [
@@ -121,6 +134,32 @@ public function getExternalUrl() {
       ->toString();
   }
 
+  /**
+   * Returns the target of the resource within the stream.
+   *
+   * XXX: Effectively copypasta from
+   * \Drupal\Core\StreamWrapper\LocalStream::getTarget(), to facilitate parsing
+   * of the URI.
+   *
+   * @param null|string $uri
+   *   Optional URI.
+   *
+   * @return string
+   *   The coordinates of the resource.
+   *
+   * @see \Drupal\Core\StreamWrapper\LocalStream::getTarget()
+   */
+  protected function getTarget(?string $uri = NULL) : string {
+    if (!isset($uri)) {
+      $uri = $this->uri;
+    }
+
+    [, $target] = explode('://', $uri, 2);
+
+    // Remove erroneous leading or trailing, forward-slashes and backslashes.
+    return trim($target, '\/');
+  }
+
   /**
    * {@inheritdoc}
    */
@@ -139,15 +178,128 @@ public function getDescription() {
    * {@inheritDoc}
    * phpcs:disable Drupal.NamingConventions.ValidFunctionName.ScopeNotCamelCaps
    */
-  public function url_stat($uri, $flags) {
-    return static::applyMask(parent::url_stat($uri, $flags));
+  public function url_stat($path, $flags) {
+    return ($flags & STREAM_URL_STAT_QUIET) ?
+      @static::applyMask(stat($this->getLocalPath($path))) :
+      static::applyMask(stat($this->getLocalPath($path)));
   }
 
   /**
    * {@inheritDoc}
    */
   public function stream_stat() {
-    return static::applyMask(parent::stream_stat());
+    return static::applyMask(fstat($this->handle));
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function dir_closedir() {
+    trigger_error(__FUNCTION__ . '() not supported for foxml stream wrapper.', E_USER_WARNING);
+    return TRUE;
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function dir_opendir($path, $options) {
+    trigger_error(__FUNCTION__ . '() not supported for foxml stream wrapper.', E_USER_WARNING);
+    return FALSE;
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function dir_readdir() {
+    trigger_error(__FUNCTION__ . '() not supported for foxml stream wrapper.', E_USER_WARNING);
+    return FALSE;
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function dir_rewinddir() {
+    trigger_error(__FUNCTION__ . '() not supported for foxml stream wrapper.', E_USER_WARNING);
+    return FALSE;
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function stream_cast($cast_as) {
+    trigger_error(__FUNCTION__ . '() not supported for foxml stream wrapper.', E_USER_WARNING);
+    return FALSE;
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function stream_close() {
+    $result = fclose($this->handle);
+    unset($this->handle);
+    return $result;
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function stream_eof() {
+    return feof($this->handle);
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function stream_read($count) {
+    return fread($this->handle, $count);
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function stream_seek($offset, $whence = SEEK_SET) {
+    return fseek($this->handle, $offset, $whence);
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function stream_set_option($option, $arg1, $arg2) {
+    return stream_context_set_option($this->handle, $option, $arg1, $arg2);
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function stream_tell() {
+    return ftell($this->handle);
   } // phpcs:enable Drupal.NamingConventions.ValidFunctionName.ScopeNotCamelCaps
 
+  /**
+   * {@inheritDoc}
+   */
+  public static function getType() {
+    return StreamWrapperInterface::HIDDEN;
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function realpath() {
+    // XXX: Avoiding spamming via trigger_error() here, as we expect this to be
+    // called legitimately, such as from:
+    // - https://git.drupalcode.org/project/imagemagick/-/blob/218b8bb59225232eb502862c202a7a3849cf0e6e/src/EventSubscriber/ImagemagickEventSubscriber.php#L136
+    return FALSE;
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function dirname($uri = NULL) {
+    // XXX: Avoiding spamming via trigger_error() here, as we expect this to be
+    // called legitimately, such as from:
+    // - https://github.com/discoverygarden/dgi_migrate/blob/a93b0ce642db6f0ecdde4d184a501c280fb9d2ed/src/Plugin/migrate/process/EnsureNonWritableTrait.php#L52-L56
+    return FALSE;
+  }
+
 }