MDL-72133 report_log: Add fallback context display

report/log/classes/helper.php

@@ -0,0 +1,60 @@
+<?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/>.
+
+namespace report_log;
+
+/**
+ * Helper class for displaying logs.
+ *
+ * @package    report_log
+ * @copyright  2024 Benjamin Walker <[email protected]>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class helper {
+
+    /**
+     * Returns a string that attempts to infer event context display when context no longer exists.
+     * This can be used to show a minimum amount of info in log tables, but ideally this would
+     * be a last resort as log display should not change.
+     *
+     * @param \core\event\base|\stdClass $event
+     * @return string inferred context display, or an empty string.
+     */
+    public static function get_context_fallback(\core\event\base|\stdClass $event): string {
+        if (empty($event) || empty($event->contextlevel) || empty($event->component)) {
+            return '';
+        }
+
+        $name = \context_helper::get_level_name($event->contextlevel);
+        $instanceid = $event->contextinstanceid ?? '';
+
+        // Use the plugin name for modules and blocks.
+        if ($event->contextlevel == CONTEXT_MODULE || $event->contextlevel == CONTEXT_BLOCK) {
+            // Some events list the component as core and store the modulename in other.
+            $component = !empty($event->other['modulename']) ? 'mod_' . $event->other['modulename'] : $event->component;
+
+            // Use module name to keep names consistent. Making component human readable is a close approximation.
+            $modulename = preg_replace('/^(mod_|block_)/', '', $component);
+            $name = str_replace('_', ' ', $modulename);
+        }
+
+        // Can't access context get_url methods, so don't bother showing a url.
+        return get_string('missingcontext', 'report_log', [
+            'name' => strtolower($name),
+            'instanceid' => $instanceid,
+        ]);
+    }
+}

report/log/classes/table_log.php

@@ -248,7 +248,7 @@ class report_log_table_log extends table_sql {
                     if (empty($this->download) && $url = $context->get_url()) {
                         $contextname = html_writer::link($url, $contextname);
                     }
-                } else {
+                } else if (!$contextname = \report_log\helper::get_context_fallback($event)) {
                     $contextname = get_string('other');
                 }
             }

report/log/lang/en/report_log.php

@@ -37,6 +37,7 @@ $string['log:view'] = 'View course logs';
 $string['log:viewtoday'] = 'View today\'s logs';
 $string['page'] = 'Page {$a}';
 $string['logsformat'] = 'Logs format';
+$string['missingcontext'] = 'Deleted {$a->name} (id \'{$a->instanceid}\')';
 $string['missingcourse'] = 'Missing course (id \'{$a->instanceid}\')';
 $string['nocapability'] = 'Can not access user log report';
 $string['nologreaderenabled'] = 'No log reader enabled';

report/loglive/classes/table_log.php

@@ -196,7 +196,7 @@ class report_loglive_table_log extends table_sql {
                     if ($url = $context->get_url()) {
                         $contextname = html_writer::link($url, $contextname);
                     }
-                } else {
+                } else if (!$contextname = \report_log\helper::get_context_fallback($event)) {
                     $contextname = get_string('other');
                 }
             }