From 446cd0dfe171d9c9ff9e6be3aeb0d9fe657d7e60 Mon Sep 17 00:00:00 2001
From: Aleksander Machniak <machniak@kolabsys.com>
Date: Sat, 13 Feb 2016 13:09:59 +0100
Subject: [PATCH] Performance: Limit number of SQL queries needed for "object
 relations update" operation

---
 .../calendar/drivers/kolab/kolab_calendar.php |  8 +-----
 plugins/kolab_notes/kolab_notes.php           |  6 +----
 plugins/libkolab/lib/kolab_storage_config.php | 26 +++++++++++--------
 .../drivers/kolab/tasklist_kolab_driver.php   |  8 +-----
 4 files changed, 18 insertions(+), 30 deletions(-)

diff --git a/plugins/calendar/drivers/kolab/kolab_calendar.php b/plugins/calendar/drivers/kolab/kolab_calendar.php
index 9043b4a9..a2ff6ee9 100644
--- a/plugins/calendar/drivers/kolab/kolab_calendar.php
+++ b/plugins/calendar/drivers/kolab/kolab_calendar.php
@@ -572,14 +572,8 @@ class kolab_calendar extends kolab_storage_folder_api
    */
   protected function save_links($uid, $links)
   {
-    // make sure we have a valid array
-    if (empty($links)) {
-      $links = array();
-    }
-
     $storage = kolab_storage_config::get_instance();
-    $remove = array_diff($storage->get_object_links($uid), $links);
-    return $storage->save_object_links($uid, $links, $remove);
+    return $storage->save_object_links($uid, (array) $links);
   }
 
   /**
diff --git a/plugins/kolab_notes/kolab_notes.php b/plugins/kolab_notes/kolab_notes.php
index 58741c65..18e15444 100644
--- a/plugins/kolab_notes/kolab_notes.php
+++ b/plugins/kolab_notes/kolab_notes.php
@@ -1247,12 +1247,8 @@ class kolab_notes extends rcube_plugin
 
     private function save_links($uid, $links)
     {
-        if (empty($links)) {
-            $links = array();
-        }
         $config = kolab_storage_config::get_instance();
-        $remove = array_diff($config->get_object_links($uid), $links);
-        return $config->save_object_links($uid, $links, $remove);
+        return $config->save_object_links($uid, (array) $links);
     }
 
     /**
diff --git a/plugins/libkolab/lib/kolab_storage_config.php b/plugins/libkolab/lib/kolab_storage_config.php
index e843e976..cd295267 100644
--- a/plugins/libkolab/lib/kolab_storage_config.php
+++ b/plugins/libkolab/lib/kolab_storage_config.php
@@ -711,7 +711,8 @@ class kolab_storage_config
      * Find objects linked with the given groupware object through a relation
      *
      * @param string Object UUID
-     * @param array List of related URIs
+     *
+     * @return array List of related URIs
      */
     public function get_object_links($uid)
     {
@@ -735,27 +736,30 @@ class kolab_storage_config
     }
 
     /**
+     * Save relations of an object.
+     * Note, that we already support only one-to-one relations.
+     * So, all relations to the object that are not provided in $links
+     * argument will be removed.
      *
+     * @param string $uid   Object UUID
+     * @param array  $links List of related-object URIs
+     *
+     * @return bool True on success, False on failure
      */
-    public function save_object_links($uid, $links, $remove = array())
+    public function save_object_links($uid, $links)
     {
         $object_uri = self::build_member_url($uid);
-        $relations = $this->get_relations_for_member($uid);
-        $done = false;
+        $relations  = $this->get_relations_for_member($uid);
+        $done       = false;
 
         foreach ($relations as $relation) {
             // make relation members up-to-date
             kolab_storage_config::resolve_members($relation);
 
             // remove and add links
-            $members = array_diff($relation['members'], (array)$remove);
+            $members = array($object_uri);
             $members = array_unique(array_merge($members, $links));
 
-            // make sure the object_uri is still a member
-            if (!in_array($object_uri, $members)) {
-                $members[$object_uri];
-            }
-
             // remove relation if no other members remain
             if (count($members) <= 1) {
                 $done = $this->delete($relation['uid']);
@@ -768,7 +772,7 @@ class kolab_storage_config
             }
             // no changes, we're happy
             else {
-                $done = true;
+                $done  = true;
                 $links = array();
             }
         }
diff --git a/plugins/tasklist/drivers/kolab/tasklist_kolab_driver.php b/plugins/tasklist/drivers/kolab/tasklist_kolab_driver.php
index 885340ed..9de33dc4 100644
--- a/plugins/tasklist/drivers/kolab/tasklist_kolab_driver.php
+++ b/plugins/tasklist/drivers/kolab/tasklist_kolab_driver.php
@@ -1114,14 +1114,8 @@ class tasklist_kolab_driver extends tasklist_driver
      */
     private function save_links($uid, $links)
     {
-        // make sure we have a valid array
-        if (empty($links)) {
-            $links = array();
-        }
-
         $config = kolab_storage_config::get_instance();
-        $remove = array_diff($config->get_object_links($uid), $links);
-        return $config->save_object_links($uid, $links, $remove);
+        return $config->save_object_links($uid, (array) $links);
     }
 
     /**