From 519c932cd63749843dbbb2af883793d5c937ee0c Mon Sep 17 00:00:00 2001
From: Brendan Heywood <brendan@catalyst-au.net>
Date: Wed, 22 Jun 2022 16:32:05 +1000
Subject: [PATCH] MDL-75014 core: Add xyz_before_session_start callback

---
 lib/setup.php   | 13 +++++++++++++
 lib/upgrade.txt |  1 +
 2 files changed, 14 insertions(+)

diff --git a/lib/setup.php b/lib/setup.php
index a49539753ff..52a8dc3cffe 100644
--- a/lib/setup.php
+++ b/lib/setup.php
@@ -826,6 +826,19 @@ if (empty($CFG->sessiontimeout)) {
 if (empty($CFG->sessiontimeoutwarning)) {
     $CFG->sessiontimeoutwarning = 20 * 60;
 }
+
+// Allow plugins to callback just before the session is started.
+$pluginswithfunction = get_plugins_with_function('before_session_start', 'lib.php');
+foreach ($pluginswithfunction as $plugins) {
+    foreach ($plugins as $function) {
+        try {
+            $function();
+        } catch (Throwable $e) {
+            debugging("Exception calling '$function'", DEBUG_DEVELOPER, $e->getTrace());
+        }
+    }
+}
+
 \core\session\manager::start();
 
 if (!empty($CFG->proxylogunsafe) || !empty($CFG->proxyfixunsafe)) {
diff --git a/lib/upgrade.txt b/lib/upgrade.txt
index 0410498f3dd..357880cdb7b 100644
--- a/lib/upgrade.txt
+++ b/lib/upgrade.txt
@@ -41,6 +41,7 @@ information provided here is intended especially for developers.
   implemented by adhoc tasks. For backwards compatibility, a default implementation has been added to `\core\task\adhoc_task` to
   return the class name.
 * The function get_module_metadata() has been finally deprecated and can not be used anymore.
+* Allow plugins to callback on all pages just prior to the session start.
 
 === 4.0 ===