From 5bc2f27b25eaf7c1fca105521654c4faf493f706 Mon Sep 17 00:00:00 2001
From: Marcel Werk <burntime@woltlab.com>
Date: Fri, 24 Apr 2020 17:02:40 +0200
Subject: [PATCH] Avoid potential race condition when saving profile visitors

---
 .../visitor/UserProfileVisitorAction.class.php  | 17 +++++++++++++++++
 .../install/files/lib/page/UserPage.class.php   | 16 +++++-----------
 2 files changed, 22 insertions(+), 11 deletions(-)

diff --git a/wcfsetup/install/files/lib/data/user/profile/visitor/UserProfileVisitorAction.class.php b/wcfsetup/install/files/lib/data/user/profile/visitor/UserProfileVisitorAction.class.php
index dbdf785ad0..2f7f6d4f12 100644
--- a/wcfsetup/install/files/lib/data/user/profile/visitor/UserProfileVisitorAction.class.php
+++ b/wcfsetup/install/files/lib/data/user/profile/visitor/UserProfileVisitorAction.class.php
@@ -82,4 +82,21 @@ class UserProfileVisitorAction extends AbstractDatabaseObjectAction implements I
 			'template' => WCF::getTPL()->fetch('groupedUserList')
 		];
 	}
+	
+	/**
+	 * Inserts a new visitor if it does not already exist, or updates it if it does.
+	 * @since       5.2
+	 */
+	public function registerVisitor() {
+		$sql = "INSERT INTO             wcf".WCF_N."_user_profile_visitor
+						(ownerID, userID, time)
+			VALUES                  (?, ?, ?)
+			ON DUPLICATE KEY UPDATE time = VALUES(time)";
+		$statement = WCF::getDB()->prepareStatement($sql);
+		$statement->execute([
+			$this->parameters['data']['ownerID'],
+			$this->parameters['data']['userID'],
+			$this->parameters['data']['time'] ?? TIME_NOW,
+		]);
+	}
 }
diff --git a/wcfsetup/install/files/lib/page/UserPage.class.php b/wcfsetup/install/files/lib/page/UserPage.class.php
index 96c7c6574a..072232effe 100644
--- a/wcfsetup/install/files/lib/page/UserPage.class.php
+++ b/wcfsetup/install/files/lib/page/UserPage.class.php
@@ -6,8 +6,7 @@ use wcf\data\user\cover\photo\UserCoverPhoto;
 use wcf\data\user\follow\UserFollowerList;
 use wcf\data\user\follow\UserFollowingList;
 use wcf\data\user\group\UserGroup;
-use wcf\data\user\profile\visitor\UserProfileVisitor;
-use wcf\data\user\profile\visitor\UserProfileVisitorEditor;
+use wcf\data\user\profile\visitor\UserProfileVisitorAction;
 use wcf\data\user\profile\visitor\UserProfileVisitorList;
 use wcf\data\user\UserEditor;
 use wcf\data\user\UserProfile;
@@ -180,17 +179,12 @@ class UserPage extends AbstractPage {
 			// save visitor
 			/** @noinspection PhpUndefinedFieldInspection */
 			if (PROFILE_ENABLE_VISITORS && WCF::getUser()->userID && !WCF::getUser()->canViewOnlineStatus) {
-				if (($visitor = UserProfileVisitor::getObject($this->user->userID, WCF::getUser()->userID)) !== null) {
-					$editor = new UserProfileVisitorEditor($visitor);
-					$editor->update(['time' => TIME_NOW]);
-				}
-				else {
-					UserProfileVisitorEditor::create([
+				(new UserProfileVisitorAction([], 'registerVisitor', [
+					'data' => [
 						'ownerID' => $this->user->userID,
 						'userID' => WCF::getUser()->userID,
-						'time' => TIME_NOW
-					]);
-				}
+					]
+				]))->executeAction();
 			}
 		}
 		
-- 
2.20.1