Issue #2473179 by Fabianx, Berdir, dawehner: Use FileCache for config storage

core/lib/Drupal/Core/Config/ExtensionInstallStorage.php

@@ -44,9 +44,8 @@ class ExtensionInstallStorage extends InstallStorage {
    *   search and to get overrides from.
    */
   public function __construct(StorageInterface $config_storage, $directory = self::CONFIG_INSTALL_DIRECTORY, $collection = StorageInterface::DEFAULT_COLLECTION, $include_profile = TRUE) {
+    parent::__construct($directory, $collection);
     $this->configStorage = $config_storage;
-    $this->directory = $directory;
-    $this->collection = $collection;
     $this->includeProfile = $include_profile;
   }
 

core/lib/Drupal/Core/Config/FileStorage.php

@@ -2,6 +2,7 @@
 
 namespace Drupal\Core\Config;
 
+use Drupal\Component\FileCache\FileCacheFactory;
 use Drupal\Component\Serialization\Yaml;
 use Drupal\Component\Serialization\Exception\InvalidDataTypeException;
 
@@ -24,6 +25,13 @@ class FileStorage implements StorageInterface {
    */
   protected $directory = '';
 
+  /**
+   * The file cache object.
+   *
+   * @var \Drupal\Component\FileCache\FileCacheInterface
+   */
+  protected $fileCache;
+
   /**
    * Constructs a new FileStorage.
    *
@@ -36,6 +44,11 @@ class FileStorage implements StorageInterface {
   public function __construct($directory, $collection = StorageInterface::DEFAULT_COLLECTION) {
     $this->directory = $directory;
     $this->collection = $collection;
+
+    // Use a NULL File Cache backend by default. This will ensure only the
+    // internal statc caching of FileCache is used and thus avoids blowing up
+    // the APCu cache.
+    $this->fileCache = FileCacheFactory::get('config', ['cache_backend_class' => NULL]);
   }
 
   /**
@@ -90,7 +103,12 @@ class FileStorage implements StorageInterface {
     if (!$this->exists($name)) {
       return FALSE;
     }
+
     $filepath = $this->getFilePath($name);
+    if ($data = $this->fileCache->get($filepath)) {
+      return $data;
+    }
+
     $data = file_get_contents($filepath);
     try {
       $data = $this->decode($data);
@@ -98,6 +116,8 @@ class FileStorage implements StorageInterface {
     catch (InvalidDataTypeException $e) {
       throw new UnsupportedDataTypeConfigException('Invalid data type in config ' . $name . ', found in file' . $filepath . ' : ' . $e->getMessage());
     }
+    $this->fileCache->set($filepath, $data);
+
     return $data;
   }
 
@@ -119,18 +139,18 @@ class FileStorage implements StorageInterface {
    */
   public function write($name, array $data) {
     try {
-      $data = $this->encode($data);
+      $encoded_data = $this->encode($data);
     }
     catch (InvalidDataTypeException $e) {
       throw new StorageException("Invalid data type in config $name: {$e->getMessage()}");
     }
 
     $target = $this->getFilePath($name);
-    $status = @file_put_contents($target, $data);
+    $status = @file_put_contents($target, $encoded_data);
     if ($status === FALSE) {
       // Try to make sure the directory exists and try writing again.
       $this->ensureStorage();
-      $status = @file_put_contents($target, $data);
+      $status = @file_put_contents($target, $encoded_data);
     }
     if ($status === FALSE) {
       throw new StorageException('Failed to write configuration file: ' . $this->getFilePath($name));
@@ -138,6 +158,9 @@ class FileStorage implements StorageInterface {
     else {
       drupal_chmod($target);
     }
+
+    $this->fileCache->set($target, $data);
+
     return TRUE;
   }
 
@@ -152,6 +175,7 @@ class FileStorage implements StorageInterface {
       }
       return FALSE;
     }
+    $this->fileCache->delete($this->getFilePath($name));
     return drupal_unlink($this->getFilePath($name));
   }
 
@@ -163,6 +187,8 @@ class FileStorage implements StorageInterface {
     if ($status === FALSE) {
       throw new StorageException('Failed to rename configuration file from: ' . $this->getFilePath($name) . ' to: ' . $this->getFilePath($new_name));
     }
+    $this->fileCache->delete($this->getFilePath($name));
+    $this->fileCache->delete($this->getFilePath($new_name));
     return TRUE;
   }
 

core/lib/Drupal/Core/Config/InstallStorage.php

@@ -58,8 +58,7 @@ class InstallStorage extends FileStorage {
    *   default collection.
    */
   public function __construct($directory = self::CONFIG_INSTALL_DIRECTORY, $collection = StorageInterface::DEFAULT_COLLECTION) {
-    $this->directory = $directory;
-    $this->collection = $collection;
+    parent::__construct($directory, $collection);
   }
 
   /**