From 903089793362a64294e934bbefd4608bd14f74e9 Mon Sep 17 00:00:00 2001
From: Arthur Schiwon <blizzz@arthur-schiwon.de>
Date: Wed, 8 Jan 2020 11:02:37 +0100
Subject: [PATCH] cache group existence early to save useless requests to LDAP

we do it for users already

Signed-off-by: Arthur Schiwon <blizzz@arthur-schiwon.de>
---
 apps/user_ldap/lib/Access.php     | 21 +++++++++++++++++++--
 apps/user_ldap/lib/Group_LDAP.php |  2 +-
 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/apps/user_ldap/lib/Access.php b/apps/user_ldap/lib/Access.php
index 6104c908a8..fcc64ae0dc 100644
--- a/apps/user_ldap/lib/Access.php
+++ b/apps/user_ldap/lib/Access.php
@@ -345,7 +345,7 @@ class Access extends LDAPUtility {
 		}
 		return [];
 	}
-	
+
 	/**
 	 * Set password for an LDAP user identified by a DN
 	 *
@@ -652,6 +652,8 @@ class Access extends LDAPUtility {
 			if ($this->ncUserManager instanceof PublicEmitter && $isUser) {
 				$this->cacheUserExists($name);
 				$this->ncUserManager->emit('\OC\User', 'assignedUserId', [$name]);
+			} elseif (!$isUser) {
+				$this->cacheGroupExists($name);
 			}
 			return true;
 		}
@@ -761,6 +763,13 @@ class Access extends LDAPUtility {
 		$this->connection->writeToCache('userExists'.$ocName, true);
 	}
 
+	/**
+	 * caches a group as existing
+	 */
+	public function cacheGroupExists(string $gid): void {
+		$this->connection->writeToCache('groupExists'.$gid, true);
+	}
+
 	/**
 	 * caches the user display name
 	 *
@@ -958,7 +967,15 @@ class Access extends LDAPUtility {
 	 * @return array
 	 */
 	public function fetchListOfGroups($filter, $attr, $limit = null, $offset = null) {
-		return $this->fetchList($this->searchGroups($filter, $attr, $limit, $offset), $this->manyAttributes($attr));
+		$groupRecords = $this->searchGroups($filter, $attr, $limit, $offset);
+		array_walk($groupRecords, function($record) {
+			$newlyMapped = false;
+			$gid = $this->dn2ocname($record['dn'][0], null, false, $newlyMapped, $record);
+			if(!$newlyMapped && is_string($gid)) {
+				$this->cacheGroupExists($gid);
+			}
+		});
+		return $this->fetchList($groupRecords, $this->manyAttributes($attr));
 	}
 
 	/**
diff --git a/apps/user_ldap/lib/Group_LDAP.php b/apps/user_ldap/lib/Group_LDAP.php
index 0a348c2ee6..0c4b7182ec 100644
--- a/apps/user_ldap/lib/Group_LDAP.php
+++ b/apps/user_ldap/lib/Group_LDAP.php
@@ -1147,7 +1147,7 @@ class Group_LDAP extends BackendUtility implements \OCP\GroupInterface, IGroupLD
 						$uuid,
 						false
 					);
-					$this->access->connection->writeToCache("groupExists" . $gid, true);
+					$this->access->cacheGroupExists($gid);
 				}
 			}
 			return $dn != null;