Various optimizations:

o Add model_cache::get() which caches models avoiding duplicate lookups
o Stop using ORM relationships for Item_Model::owner so that we can use caching
o For Item_Model::xxx_edit fields, don't make them editable for guests
o Other minor stuff.

These optimizations reduce the number of queries for a 9-photos page from ~200
to ~45.  Still way too many!

2 files changed, 51 insertions, 32 deletions

diff --git a/core/helpers/access.php b/core/helpers/access.php
index f40a5c7c..eda91d65 100644
--- a/core/helpers/access.php
+++ b/core/helpers/access.php
@@ -79,15 +79,8 @@ class access_Core {
    * @return boolean
    */
   public static function group_can($group, $perm_name, $item) {
-    if ($perm_name == "view") {
-      $resource = $item;
-    } else {
-      $resource = ORM::factory("access_cache")->where("item_id", $item->id)->find();
-      if (!$resource) {
-        throw new Exception("@todo MISSING_ACCESS for $item->id");
-      }
-    }
-
+    $resource = $perm_name == "view" ?
+      $item : model_cache::get("access_cache", $item->id, "item_id");
     return $resource->__get("{$perm_name}_{$group->id}") === self::ALLOW;
   }
 
@@ -103,15 +96,8 @@ class access_Core {
       return false;
     }
 
-    if ($perm_name == "view") {
-      $resource = $item;
-    } else {
-      $resource = ORM::factory("access_cache")->where("item_id", $item->id)->find();
-      if (!$resource) {
-        throw new Exception("@todo MISSING_ACCESS for $item->id");
-      }
-    }
-
+    $resource = $perm_name == "view" ?
+      $item : model_cache::get("access_cache", $item->id, "item_id");
     foreach (user::active()->groups as $group) {
       if ($resource->__get("{$perm_name}_{$group->id}") === self::ALLOW) {
         return true;
@@ -135,11 +121,7 @@ class access_Core {
     if ($album->type != "album") {
       throw new Exception("@todo INVALID_ALBUM_TYPE not an album");
     }
-    $access = ORM::factory("access_intent")->where("item_id", $album->id)->find();
-    if (!$access->loaded) {
-      throw new Exception("@todo MISSING_ACCESS for $album->id");
-    }
-
+    $access = model_cache::get("access_intent", $album->id, "item_id");
     $access->__set("{$perm_name}_{$group->id}", $value);
     $access->save();
 
@@ -268,17 +250,19 @@ class access_Core {
     $access_intent->save();
 
     // Create a new access cache entry and copy the parents values.
-    $parent_access_cache =
-      ORM::factory("access_cache")->where("item_id", $item->parent()->id)->find();
     $access_cache = ORM::factory("access_cache");
     $access_cache->item_id = $item->id;
-    foreach (self::_get_all_groups() as $group) {
-      foreach (ORM::factory("permission")->find_all() as $perm) {
-        $field = "{$perm->name}_{$group->id}";
-        if ($perm->name == "view") {
-          $item->$field = $item->parent()->$field;
-        } else {
-          $access_cache->$field = $parent_access_cache->$field;
+    if ($item->id != 1) {
+      $parent_access_cache =
+        ORM::factory("access_cache")->where("item_id", $item->parent()->id)->find();
+      foreach (self::_get_all_groups() as $group) {
+        foreach (ORM::factory("permission")->find_all() as $perm) {
+          $field = "{$perm->name}_{$group->id}";
+          if ($perm->name == "view") {
+            $item->$field = $item->parent()->$field;
+          } else {
+            $access_cache->$field = $parent_access_cache->$field;
+          }
         }
       }
     }
diff --git a/core/helpers/model_cache.php b/core/helpers/model_cache.php
new file mode 100644
index 00000000..7a01393b
--- /dev/null
+++ b/core/helpers/model_cache.php
@@ -0,0 +1,35 @@
+<?php defined("SYSPATH") or die("No direct script access.");
+/**
+ * Gallery - a web based photo album viewer and editor
+ * Copyright (C) 2000-2008 Bharat Mediratta
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+class model_cache_Core {
+  private static $cache;
+
+  function get($model_name,  $id, $field_name="id") {
+    if (TEST_MODE || empty(self::$cache->$model_name->$field_name->$id)) {
+      $model = ORM::factory($model_name)->where($field_name, $id)->find();
+      if (!$model->loaded) {
+        throw new Exception("@todo MISSING_MODEL $model_name:$id");
+      }
+      self::$cache->$model_name->$field_name->$id = $model;
+    }
+
+
+    return self::$cache->$model_name->$field_name->$id;
+  }
+}