From 9e217d8441d916fdf52ec1d2500dad9ccd782592 Mon Sep 17 00:00:00 2001
From: Andrew Nicols <andrew@nicols.co.uk>
Date: Thu, 18 Oct 2018 14:16:57 +0800
Subject: [PATCH] MDL-62560 tool_dataprivacy: Add a purpose override cache

---
 .../dataprivacy/classes/purpose_override.php  | 48 ++++++++++++++++++-
 admin/tool/dataprivacy/db/caches.php          |  7 +++
 .../dataprivacy/lang/en/tool_dataprivacy.php  |  1 +
 admin/tool/dataprivacy/version.php            |  2 +-
 4 files changed, 55 insertions(+), 3 deletions(-)

diff --git a/admin/tool/dataprivacy/classes/purpose_override.php b/admin/tool/dataprivacy/classes/purpose_override.php
index b3ee4182198..5b022ab8633 100644
--- a/admin/tool/dataprivacy/classes/purpose_override.php
+++ b/admin/tool/dataprivacy/classes/purpose_override.php
@@ -89,11 +89,55 @@ class purpose_override extends \core\persistent {
      * @return  array
      */
     public static function get_overrides_for_purpose(purpose $purpose) : array {
+        $cache = \cache::make('tool_dataprivacy', 'purpose_overrides');
+
         $overrides = [];
-        foreach (self::get_records(['purposeid' => $purpose->get('id')]) as $override) {
-            $overrides[$override->get('roleid')] = $override;
+        $alldata = $cache->get($purpose->get('id'));
+        if (false === $alldata) {
+            $tocache = [];
+            foreach (self::get_records(['purposeid' => $purpose->get('id')]) as $override) {
+                $tocache[] = $override->to_record();
+                $overrides[$override->get('roleid')] = $override;
+            }
+            $cache->set($purpose->get('id'), $tocache);
+        } else {
+            foreach ($alldata as $data) {
+                $override = new self(0, $data);
+                $overrides[$override->get('roleid')] = $override;
+            }
         }
 
         return $overrides;
     }
+
+    /**
+     * Adds the new record to the cache.
+     *
+     * @return null
+     */
+    protected function after_create() {
+        $cache = \cache::make('tool_dataprivacy', 'purpose_overrides');
+        $cache->delete($this->get('purposeid'));
+    }
+
+    /**
+     * Updates the cache record.
+     *
+     * @param bool $result
+     * @return null
+     */
+    protected function after_update($result) {
+        $cache = \cache::make('tool_dataprivacy', 'purpose_overrides');
+        $cache->delete($this->get('purposeid'));
+    }
+
+    /**
+     * Removes unnecessary stuff from db.
+     *
+     * @return null
+     */
+    protected function before_delete() {
+        $cache = \cache::make('tool_dataprivacy', 'purpose_overrides');
+        $cache->delete($this->get('purposeid'));
+    }
 }
diff --git a/admin/tool/dataprivacy/db/caches.php b/admin/tool/dataprivacy/db/caches.php
index 00124bb34c0..a07db1a11bd 100644
--- a/admin/tool/dataprivacy/db/caches.php
+++ b/admin/tool/dataprivacy/db/caches.php
@@ -33,6 +33,13 @@ $definitions = array(
         'staticacceleration' => true,
         'staticaccelerationsize' => 30,
     ),
+    'purpose_overrides' => array(
+        'mode' => cache_store::MODE_APPLICATION,
+        'simplekeys' => true,
+        'simpledata' => false,
+        'staticacceleration' => true,
+        'staticaccelerationsize' => 50,
+    ),
     'contextlevel' => array(
         'mode' => cache_store::MODE_APPLICATION,
         'simplekeys' => true,
diff --git a/admin/tool/dataprivacy/lang/en/tool_dataprivacy.php b/admin/tool/dataprivacy/lang/en/tool_dataprivacy.php
index 5206d2261dc..448435f69da 100644
--- a/admin/tool/dataprivacy/lang/en/tool_dataprivacy.php
+++ b/admin/tool/dataprivacy/lang/en/tool_dataprivacy.php
@@ -35,6 +35,7 @@ $string['approverequest'] = 'Approve request';
 $string['bulkapproverequests'] = 'Approve requests';
 $string['bulkdenyrequests'] = 'Deny requests';
 $string['cachedef_purpose'] = 'Data purposes';
+$string['cachedef_purpose_overrides'] = 'Purpose overrides in the Data Privacy tool';
 $string['cachedef_contextlevel'] = 'Context levels purpose and category';
 $string['cancelrequest'] = 'Cancel request';
 $string['cancelrequestconfirmation'] = 'Do you really want cancel this data request?';
diff --git a/admin/tool/dataprivacy/version.php b/admin/tool/dataprivacy/version.php
index bb982419edb..3efc437a0ce 100644
--- a/admin/tool/dataprivacy/version.php
+++ b/admin/tool/dataprivacy/version.php
@@ -24,6 +24,6 @@
 
 defined('MOODLE_INTERNAL') || die;
 
-$plugin->version   = 2018100401;
+$plugin->version   = 2018100403;
 $plugin->requires  = 2018050800;        // Moodle 3.5dev (Build 2018031600) and upwards.
 $plugin->component = 'tool_dataprivacy';