From fbb36f89770ac0196efa646e55156deeabbaf584 Mon Sep 17 00:00:00 2001
From: Brendan Heywood <brendan@catalyst-au.net>
Date: Wed, 2 Jun 2021 11:57:39 +1000
Subject: [PATCH] MDL-67822 report_performance: Add DB schema check

---
 lib/classes/check/manager.php                 |  1 +
 lib/classes/check/performance/dbschema.php    | 85 +++++++++++++++++++
 .../lang/en/report_performance.php            |  3 +
 3 files changed, 89 insertions(+)
 create mode 100644 lib/classes/check/performance/dbschema.php

diff --git a/lib/classes/check/manager.php b/lib/classes/check/manager.php
index 69ebcc65e9d..e4b35f88927 100644
--- a/lib/classes/check/manager.php
+++ b/lib/classes/check/manager.php
@@ -69,6 +69,7 @@ class manager {
             new performance\debugging(),
             new performance\backups(),
             new performance\stats(),
+            new performance\dbschema(),
         ];
 
         // Any plugin can add status checks to this report by implementing a callback
diff --git a/lib/classes/check/performance/dbschema.php b/lib/classes/check/performance/dbschema.php
new file mode 100644
index 00000000000..cdbb8957938
--- /dev/null
+++ b/lib/classes/check/performance/dbschema.php
@@ -0,0 +1,85 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle 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 Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * DB schema performance check
+ *
+ * @package    core
+ * @category   check
+ * @copyright  2021 Brendan Heywood <brendan@catalyst-au.net>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace core\check\performance;
+
+defined('MOODLE_INTERNAL') || die();
+
+use core\check\check;
+use core\check\result;
+
+/**
+ * DB schema performance check
+ *
+ * @copyright  2021 Brendan Heywood <brendan@catalyst-au.net>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class dbschema extends check {
+
+    /**
+     * Get the short check name
+     *
+     * @return string
+     */
+    public function get_name(): string {
+        return get_string('check_dbschema_name', 'report_performance');
+    }
+
+    /**
+     * A link to a place to action this
+     *
+     * @return action_link|null
+     */
+    public function get_action_link(): ?\action_link {
+        return new \action_link(
+            new \moodle_url(\get_docs_url('Verify_Database_Schema')),
+            get_string('moodledocs'));
+    }
+
+    /**
+     * Return result
+     * @return result
+     */
+    public function get_result(): result {
+        global $DB;
+
+        $dbmanager = $DB->get_manager();
+        $schema = $dbmanager->get_install_xml_schema();
+
+        if (!$errors = $dbmanager->check_database_schema($schema)) {
+            return new result(result::OK, get_string('check_dbschema_ok', 'report_performance'), '');
+        }
+
+        $details = '';
+        foreach ($errors as $tablename => $items) {
+            $details .= \html_writer::tag('h4', $tablename);
+            foreach ($items as $item) {
+                $details .= \html_writer::tag('pre', $item);
+            }
+        }
+        return new result(result::ERROR, get_string('check_dbschema_errors', 'report_performance'), $details);
+    }
+}
+
diff --git a/report/performance/lang/en/report_performance.php b/report/performance/lang/en/report_performance.php
index 57e08425943..f7172566f25 100644
--- a/report/performance/lang/en/report_performance.php
+++ b/report/performance/lang/en/report_performance.php
@@ -29,6 +29,9 @@ $string['check_backup_details'] = 'Enabling automated backup will automatically
 $string['check_cachejs_comment_disable'] = 'If enabled, page loading performance is improved.';
 $string['check_cachejs_comment_enable'] = 'If disabled, page might load slow.';
 $string['check_cachejs_details'] = 'Javascript caching and compression greatly improves page loading performance. It is strongly recommended for production sites.';
+$string['check_dbschema_name'] = 'Database schema check';
+$string['check_dbschema_ok'] = 'Database schema is correct.';
+$string['check_dbschema_errors'] = 'Database schema is not aligned.';
 $string['check_debugmsg_comment_nodeveloper'] = 'If set to DEVELOPER, performance may be affected slightly.';
 $string['check_debugmsg_comment_developer'] = 'If set to a value other than DEVELOPER, performance may be improved slightly.';
 $string['check_debugmsg_details'] = 'There is rarely any advantage in going to Developer level, unless requested by a developer.<p>Once you have obtained the error message, and copied and pasted it somewhere, it is HIGHLY RECOMMENDED to turn Debug back to NONE. Debug messages can give clues to a hacker as to the setup of your site and may affect performance.</p>';