From c569cec4ea49612ddc9d430d7fe792971c93c586 Mon Sep 17 00:00:00 2001
From: Garion Herman <garion@silverstripe.com>
Date: Fri, 31 May 2019 10:21:07 +1200
Subject: [PATCH] NEW Add updateHintsCacheKey extension point to fix invalid
 caching

If a module augments the allowed pagetypes based on external conditions,
the Hints Cache Key will not cover these conditions and may cause
incorrect output. An example of this is Subsites, which allows each
Subsite to have a different set of allowed pagetypes.
---
 code/Controllers/CMSMain.php | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/code/Controllers/CMSMain.php b/code/Controllers/CMSMain.php
index 5f41b325..9fa20345 100644
--- a/code/Controllers/CMSMain.php
+++ b/code/Controllers/CMSMain.php
@@ -2272,7 +2272,11 @@ class CMSMain extends LeftAndMain implements CurrentPageIdentifier, PermissionPr
      */
     protected function generateHintsCacheKey($memberID)
     {
-        return md5($memberID . '_' . __CLASS__);
+        $baseKey = $memberID . '_' . __CLASS__;
+
+        $this->extend('updateHintsCacheKey', $baseKey);
+
+        return md5($baseKey);
     }
 
     /**