From c95e501f98a5708f09258f9592c80c686d33742a Mon Sep 17 00:00:00 2001
From: Matthias Pfefferle <pfefferle@users.noreply.github.com>
Date: Tue, 30 May 2023 10:22:01 +0200
Subject: [PATCH] redirect to canonical URL if it is not an ActivityPub request

---
 includes/class-activitypub.php     |  2 +-
 includes/functions.php             |  2 +-
 includes/model/class-blog-user.php |  4 ++++
 includes/model/class-user.php      |  4 ++++
 includes/rest/class-users.php      | 10 +++++++++-
 5 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/includes/class-activitypub.php b/includes/class-activitypub.php
index 72cea52..2da2dce 100644
--- a/includes/class-activitypub.php
+++ b/includes/class-activitypub.php
@@ -227,7 +227,7 @@ class Activitypub {
 			);
 			\add_rewrite_rule(
 				'^@([\w\-\.]+)',
-				'index.php?rest_route=/' . ACTIVITYPUB_REST_NAMESPACE . '/users/$matches[1]&redirect=true',
+				'index.php?rest_route=/' . ACTIVITYPUB_REST_NAMESPACE . '/users/$matches[1]',
 				'top'
 			);
 		}
diff --git a/includes/functions.php b/includes/functions.php
index 1f25e04..dfbdf37 100644
--- a/includes/functions.php
+++ b/includes/functions.php
@@ -236,7 +236,7 @@ function is_activitypub_request() {
 	 * ActivityPub requests are currently only made for
 	 * author archives, singular posts, and the homepage.
 	 */
-	if ( ! \is_author() && ! \is_singular() && ! \is_home() ) {
+	if ( ! \is_author() && ! \is_singular() && ! \is_home() && ! defined( 'REST_REQUEST' ) && ! REST_REQUEST ) {
 		return false;
 	}
 
diff --git a/includes/model/class-blog-user.php b/includes/model/class-blog-user.php
index 2183efb..fd01aa7 100644
--- a/includes/model/class-blog-user.php
+++ b/includes/model/class-blog-user.php
@@ -55,6 +55,10 @@ class Blog_User extends User {
 		return \esc_url( \trailingslashit( get_home_url() ) . '@' . $this->get_username() );
 	}
 
+	public function get_canonical_url() {
+		return \get_home_url();
+	}
+
 	public function get_username() {
 		return \esc_html( \get_option( 'activitypub_blog_user_identifier', 'feed' ) );
 	}
diff --git a/includes/model/class-user.php b/includes/model/class-user.php
index 29b65bf..5bb1e77 100644
--- a/includes/model/class-user.php
+++ b/includes/model/class-user.php
@@ -96,6 +96,10 @@ class User {
 		return \esc_url( \get_author_posts_url( $this->user_id ) );
 	}
 
+	public function get_canonical_url() {
+		return $this->get_url();
+	}
+
 	public function get_username() {
 		return \esc_attr( \get_the_author_meta( 'login', $this->user_id ) );
 	}
diff --git a/includes/rest/class-users.php b/includes/rest/class-users.php
index c6d92ee..8c0452d 100644
--- a/includes/rest/class-users.php
+++ b/includes/rest/class-users.php
@@ -6,6 +6,8 @@ use WP_REST_Server;
 use WP_REST_Response;
 use Activitypub\User_Factory;
 
+use function Activitypub\is_activitypub_request;
+
 /**
  * ActivityPub Followers REST-Class
  *
@@ -54,6 +56,12 @@ class Users {
 			return $user;
 		}
 
+		// redirect to canonical URL if it is not an ActivityPub request
+		if ( ! is_activitypub_request() ) {
+			header( 'Location: ' . $user->get_canonical_url() );
+			exit;
+		}
+
 		/*
 		 * Action triggerd prior to the ActivityPub profile being created and sent to the client
 		 */
@@ -81,7 +89,7 @@ class Users {
 
 		$params['user_id'] = array(
 			'required' => true,
-			'type' => 'string',
+			'type'     => 'string',
 		);
 
 		return $params;