1 files changed, 20 insertions, 6 deletions
diff --git a/lib/private/files/cache/storage.php b/lib/private/files/cache/storage.php
index 2007f0c9e3d..ebef245f399 100644
--- a/lib/private/files/cache/storage.php
+++ b/lib/private/files/cache/storage.php
@@ -27,9 +27,13 @@
 namespace OC\Files\Cache;
 
 /**
- * Class Storage
+ * Handle the mapping between the string and numeric storage ids
  *
- * cache storage specific data
+ * Each storage has 2 different ids
+ * 	a string id which is generated by the storage backend and reflects the configuration of the storage (e.g. 'smb://user@host/share')
+ * 	and a numeric storage id which is referenced in the file cache
+ *
+ * A mapping between the two storage ids is stored in the database and accessible trough this class
  *
  * @package OC\Files\Cache
  */
@@ -71,7 +75,7 @@ class Storage {
 	/**
 	 * Adjusts the storage id to use md5 if too long
 	 * @param string $storageId storage id
-	 * @return unchanged $storageId if its length is less than 64 characters,
+	 * @return string unchanged $storageId if its length is less than 64 characters,
 	 * else returns the md5 of $storageId
 	 */
 	public static function adjustStorageId($storageId) {
@@ -82,14 +86,19 @@ class Storage {
 	}
 
 	/**
-	 * @return string
+	 * Get the numeric id for the storage
+	 *
+	 * @return int
 	 */
 	public function getNumericId() {
 		return $this->numericId;
 	}
 
 	/**
-	 * @return string|null
+	 * Get the string id for the storage
+	 *
+	 * @param int $numericId
+	 * @return string|null either the storage id string or null if the numeric id is not known
 	 */
 	public static function getStorageId($numericId) {
 
@@ -103,7 +112,10 @@ class Storage {
 	}
 
 	/**
-	 * @return string|null
+	 * Get the numeric of the storage with the provided string id
+	 *
+	 * @param $storageId
+	 * @return int|null either the numeric storage id or null if the storage id is not knwon
 	 */
 	public static function getNumericStorageId($storageId) {
 		$storageId = self::adjustStorageId($storageId);
@@ -118,6 +130,8 @@ class Storage {
 	}
 
 	/**
+	 * Check if a string storage id is known
+	 *
 	 * @param string $storageId
 	 * @return bool
 	 */