From 97db4d26c61ac7ac67046412d4f6ac2427becc4b Mon Sep 17 00:00:00 2001
From: Tim Otten <totten@civicrm.org>
Date: Thu, 20 Oct 2022 16:22:16 -0700
Subject: [PATCH] FiveFiftySix - Add pre-upgrade warning for deeply nested
 extension paths

---
 CRM/Upgrade/Incremental/php/FiveFiftySix.php | 36 ++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/CRM/Upgrade/Incremental/php/FiveFiftySix.php b/CRM/Upgrade/Incremental/php/FiveFiftySix.php
index 896ccd1a39..b749886ff5 100644
--- a/CRM/Upgrade/Incremental/php/FiveFiftySix.php
+++ b/CRM/Upgrade/Incremental/php/FiveFiftySix.php
@@ -21,6 +21,42 @@
  */
 class CRM_Upgrade_Incremental_php_FiveFiftySix extends CRM_Upgrade_Incremental_Base {
 
+  public function setPreUpgradeMessage(&$preUpgradeMessage, $rev, $currentVer = NULL) {
+    if ($rev === '5.56.alpha1') {
+      $preUpgradeMessage .= $this->createDeepExtMessage();
+    }
+  }
+
+  /**
+   * In 5.56, the extension-system abides by a limit on the depth of search.
+   * This improves the performance of cache-clears. The default depth
+   * should catch most/all extensions on most/all sites -- but it's
+   * possible that some sites still need a deep search.
+   *
+   * @return string
+   */
+  protected function createDeepExtMessage(): string {
+    $infinityAndBeyond = 1000;
+    $liveSystem = CRM_Extension_System::singleton();
+    $deepSystem = new CRM_Extension_System(['maxDepth' => $infinityAndBeyond]);
+    $problemKeys = array_diff($deepSystem->getFullContainer()->getKeys(), $liveSystem->getFullContainer()->getKeys());
+    if (empty($problemKeys)) {
+      return '';
+    }
+
+    $message = ts('When loading extensions, CiviCRM searches the filesystem. In v5.56+, the default search is more constrained. This improves performance, but some extensions (%1) will become invisible. To make these visible, you should either move the source-code or edit <code>civicrm.settings.php</code>. For example, you may add this line:', [
+      1 => implode(', ', array_map(
+        function($key) {
+          return '"<code>' . htmlentities($key) . '</code>"';
+        },
+        $problemKeys
+      )),
+    ]);
+    $example = htmlentities("\$civicrm_setting['domain']['ext_max_depth'] = $infinityAndBeyond;");
+
+    return "<p><strong>" . ts('WARNING') . "</strong>: {$message}</p><pre>$example</pre>";
+  }
+
   /**
    * Upgrade step; adds tasks including 'runSql'.
    *
-- 
2.25.1