From f87b80266cb83fc6ca01391958cafd4aaa26fa3c Mon Sep 17 00:00:00 2001
From: Michael <heluecht@pirati.ca>
Date: Tue, 8 Feb 2022 21:05:15 +0000
Subject: [PATCH] Display followers for followers of private forums

---
 src/Module/ActivityPub/Followers.php     |  3 ++-
 src/Protocol/ActivityPub/Transmitter.php | 23 +++++++++++++++--------
 2 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/src/Module/ActivityPub/Followers.php b/src/Module/ActivityPub/Followers.php
index fbf5bf282e..54584de182 100644
--- a/src/Module/ActivityPub/Followers.php
+++ b/src/Module/ActivityPub/Followers.php
@@ -25,6 +25,7 @@ use Friendica\BaseModule;
 use Friendica\Model\Contact;
 use Friendica\Model\User;
 use Friendica\Protocol\ActivityPub;
+use Friendica\Util\HTTPSignature;
 
 /**
  * ActivityPub Followers
@@ -45,7 +46,7 @@ class Followers extends BaseModule
 
 		$page = $_REQUEST['page'] ?? null;
 
-		$followers = ActivityPub\Transmitter::getContacts($owner, [Contact::FOLLOWER, Contact::FRIEND], 'followers', $page);
+		$followers = ActivityPub\Transmitter::getContacts($owner, [Contact::FOLLOWER, Contact::FRIEND], 'followers', $page, (string)HTTPSignature::getSigner('', $_SERVER));
 
 		header('Content-Type: application/activity+json');
 		echo json_encode($followers);
diff --git a/src/Protocol/ActivityPub/Transmitter.php b/src/Protocol/ActivityPub/Transmitter.php
index 0b7159ec90..6a1dacf0a3 100644
--- a/src/Protocol/ActivityPub/Transmitter.php
+++ b/src/Protocol/ActivityPub/Transmitter.php
@@ -36,7 +36,6 @@ use Friendica\Model\GServer;
 use Friendica\Model\Item;
 use Friendica\Model\Photo;
 use Friendica\Model\Post;
-use Friendica\Model\Profile;
 use Friendica\Model\Tag;
 use Friendica\Model\User;
 use Friendica\Network\HTTPException;
@@ -49,6 +48,7 @@ use Friendica\Util\JsonLD;
 use Friendica\Util\LDSignature;
 use Friendica\Util\Map;
 use Friendica\Util\Network;
+use Friendica\Util\Strings;
 use Friendica\Util\XML;
 
 /**
@@ -146,15 +146,16 @@ class Transmitter
 	/**
 	 * Collects a list of contacts of the given owner
 	 *
-	 * @param array     $owner  Owner array
-	 * @param int|array $rel    The relevant value(s) contact.rel should match
-	 * @param string    $module The name of the relevant AP endpoint module (followers|following)
-	 * @param integer   $page   Page number
+	 * @param array     $owner     Owner array
+	 * @param int|array $rel       The relevant value(s) contact.rel should match
+	 * @param string    $module    The name of the relevant AP endpoint module (followers|following)
+	 * @param integer   $page      Page number
+	 * @param string    $requester URL of the requester
 	 *
 	 * @return array of owners
 	 * @throws \Exception
 	 */
-	public static function getContacts($owner, $rel, $module, $page = null)
+	public static function getContacts($owner, $rel, $module, $page = null, string $requester = null)
 	{
 		$parameters = [
 			'rel' => $rel,
@@ -179,8 +180,14 @@ class Transmitter
 		$data['totalItems'] = $total;
 
 		// When we hide our friends we will only show the pure number but don't allow more.
-		$profile = Profile::getByUID($owner['uid']);
-		if (!empty($profile['hide-friends'])) {
+		$show_contacts = empty($owner['hide-friends']);
+
+		// Allow fetching the contact list when the requester is part of the list.
+		if (($owner['page-flags'] == User::PAGE_FLAGS_PRVGROUP) && !empty($requester)) {
+			$show_contacts = DBA::exists('contact', ['nurl' => Strings::normaliseLink($requester), 'rel' => $rel]);
+		}
+
+		if (!$show_contacts) {
 			return $data;
 		}