Add ICacheDriver->getAllKeys method

src/Core/Cache.php

@@ -46,6 +46,29 @@ class Cache extends \Friendica\BaseObject
 		return self::$driver;
 	}
 
+	/**
+	 * @brief Returns all the cache keys sorted alphabetically
+	 *
+	 * @return array|null Null if the driver doesn't support this feature
+	 */
+	public static function getAllKeys()
+	{
+		$time = microtime(true);
+
+		$return = self::getDriver()->getAllKeys();
+
+		// Keys are prefixed with the node hostname, let's remove it
+		array_walk($return, function (&$value) {
+			$value = preg_replace('/^' . self::getApp()->get_hostname() . ':/', '', $value);
+		});
+
+		sort($return);
+
+		self::getApp()->save_timestamp($time, 'cache');
+
+		return $return;
+	}
+
 	/**
 	 * @brief Fetch cached data according to the key
 	 *