very rudimental follower-support

- fixed rewrites to properly support @username/outbox, username/outbox, users/username/outbox, ...
- initial support for sending follow to e.g. mastodon (code commented out in api.php)
- database migration for follows table and fedusers table
- save retrieved fedusers in cache and db
- depend more on configs externaldomain, less on server_name
- properly implemented following-logic in dio
- made postForuUser static in newContent and inbox
- provide rsaprivate for signing reuests -> actPub-Servers
- change contenttype depending on use-case
- changed user json-template to have loop-back between user-template and webfinger (mastodon f.e. needs this)

README.md

@@ -53,9 +53,10 @@ To configure an apache server, add the following rewrite rules:
       RewriteRule ^@(.*)$ /federator.php?_call=fedusers/$1 [L,END]
       RewriteRule ^users/(.*)$ /federator.php?_call=fedusers/$1 [L,END]
       RewriteRule ^inbox[/]?$ /federator.php?_call=fedusers/inbox [L,END]
-      RewriteRule ^api/federator/(.+)$ federator.php?_call=$1 [L,END]
+      RewriteRule ^api/federator/(.+)$ /federator.php?_call=$1 [L,END]
       RewriteRule ^(\.well-known/.*)$ /federator.php?_call=$1 [L,END]
       RewriteRule ^(nodeinfo/2\.[01])$ /federator.php?_call=$1 [L,END]
+      RewriteRule ^([a-zA-Z0-9_-]+.*)$ /federator.php?_call=fedusers/$1 [L,END]
     </Directory>
 
 change your document root for the domain you want to use (or default one if using localhost) to the directory you installed it, with the /htdocs at the end. A user should only be able to open that file, not the other data.

htdocs/index.html

@@ -17,7 +17,7 @@
             <div class="request-box border p-4 rounded-lg mb-4 bg-gray-50 overflow-y-auto">
                 <label class="block font-medium">API target link</label>
                 <input type="text" class="target-link-input w-full p-2 border rounded-md mb-2"
-                    placeholder="Enter target link" value="federator/fedusers/grumpydevelop/outbox?page=0">
+                    placeholder="Enter target link" value="users/grumpydevelop/outbox?page=0">
 
                 <label class="block font-medium">Request type</label>
                 <input type="text" class="request-type-input w-full p-2 border rounded-md mb-2"
@@ -65,7 +65,7 @@
                 ...(profile ? { "X-Profile": profile } : {})
             };
 
-            fetch("http://localhost/api/" + targetLink, {
+            fetch("http://localhost/" + targetLink, {
                 method: requestType,
                 headers
             })
@@ -94,7 +94,7 @@
             const container = document.getElementById("request-container");
             const requestBox = container.firstElementChild.cloneNode(true);
 
-            requestBox.querySelector(".target-link-input").value = "federator/fedusers/grumpydevelop@contentnation.net/outbox?page=0";
+            requestBox.querySelector(".target-link-input").value = "users/grumpydevelop@contentnation.net/outbox?page=0";
             requestBox.querySelector(".request-type-input").value = "GET";
             requestBox.querySelector(".session-input").value = "";
             requestBox.querySelector(".profile-input").value = "";

php/federator/api.php

@@ -101,6 +101,7 @@ class Api extends Main
                 break;
             case 'fedusers':
                 $handler = new Api\FedUsers($this);
+                $this->setContentType("application/activity+json");
                 break;
             case 'v1':
                 switch ($this->paths[1]) {
@@ -110,6 +111,39 @@ class Api extends Main
                     case 'newcontent':
                         $handler = new Api\V1\NewContent($this);
                         break;
+                    /* case 'sendFollow': { // hacky implementation for testing purposes
+                        $username = $this->paths[2];
+                        $domain = $this->config['generic']['externaldomain'];
+                        $response = \Federator\DIO\Followers::sendFollowRequest(
+                            $this->dbh,
+                            $this->connector,
+                            $this->cache,
+                            $username,
+                            "admin@mastodon.local",
+                            $domain
+                        );
+                        header("Content-type: " . $this->contentType);
+                        header("Access-Control-Allow-Origin: *");
+                        header("Cache-Control: no-cache, no-store, must-revalidate");
+                        header("Pragma: no-cache");
+                        header("Expires: 0");
+                        if (is_string($response)) {
+                            $this->setResponseCode(200);
+                            $retval = json_encode(array(
+                                "status" => "ok",
+                                "message" => $response
+                            ));
+                        } else {
+                            $this->setResponseCode(500);
+                            $retval = json_encode(array(
+                                "status" => "error",
+                                "message" => "Failed to send follow request"
+                            ));
+                        }
+                        http_response_code($this->responseCode);
+                        echo $retval;
+                        return;
+                    } */
                 }
                 break;
         }

php/federator/api/fedusers.php

@@ -50,21 +50,10 @@ class FedUsers implements APIInterface
         $method = $_SERVER["REQUEST_METHOD"];
         $handler = null;
         $_username = $paths[1];
-        if (preg_match("#^([^@]+)@([^/]+)#", $_username, $matches) != 1) {
-            $hostUrl = $this->main->getHost();
-            if ($hostUrl !== false) {
-                $host = parse_url($hostUrl, PHP_URL_HOST);
-                $port = parse_url($hostUrl, PHP_URL_PORT);
-                if ($port !== null) {
-                    $host .= ":$port";
-                }
-                $_username = "$_username@$host";
-            }
-        }
         switch (sizeof($paths)) {
             case 2:
                 if ($method === 'GET') {
-                    // /fedusers/username or /@username
+                    // /users/username or /@username or /username
                     return $this->returnUserProfile($_username);
                 } else {
                     switch ($paths[1]) {
@@ -78,7 +67,7 @@ class FedUsers implements APIInterface
                 }
                 break;
             case 3:
-                // /fedusers/username/(inbox|outbox|following|followers)
+                // /users/username/(inbox|outbox|following|followers)
                 switch ($paths[2]) {
                     case 'following':
                         // $handler = new FedUsers\Following();
@@ -95,7 +84,7 @@ class FedUsers implements APIInterface
                 }
                 break;
             case 4:
-                // /fedusers/username/collections/(features|tags)
+                // /users/username/collections/(features|tags)
                 // not yet implemented
                 break;
         }
@@ -153,7 +142,7 @@ class FedUsers implements APIInterface
             'publickey' => trim($jsonKey, '"'),
             'registered' => gmdate('Y-m-d\TH:i:s\Z', $user->registered), // 2021-03-25T00:00:00Z
             'summary' => $user->summary,
-            'type' => $user->type
+            'type' => ucfirst($user->type) // capitalized user type
         ];
         $this->response = $this->main->renderTemplate('user.json', $data);
         return true;

php/federator/api/fedusers/inbox.php

@@ -60,7 +60,6 @@ class Inbox implements \Federator\Api\FedUsers\FedUsersInterface
         }
 
         $activity = is_string($_rawInput) ? json_decode($_rawInput, true) : null;
-        $host = $_SERVER['SERVER_NAME'];
 
         if (!is_array($activity)) {
             error_log("Inbox::post Input wasn't of type array");
@@ -69,10 +68,10 @@ class Inbox implements \Federator\Api\FedUsers\FedUsersInterface
 
         $inboxActivity = \Federator\Data\ActivityPub\Factory::newActivityFromJson($activity);
 
+        $rootDir = $_SERVER['DOCUMENT_ROOT'] . '../';
+
         // Shared inbox
         if (!isset($_user)) {
-            $rootDir = $_SERVER['DOCUMENT_ROOT'] . '../';
-
             // Save the raw input and parsed JSON to a file for inspection
             file_put_contents(
                 $rootDir . 'logs/inbox.log',
@@ -89,12 +88,15 @@ class Inbox implements \Federator\Api\FedUsers\FedUsersInterface
         $sendTo = $inboxActivity->getCC();
         if ($inboxActivity->getType() === 'Undo') { // for undo the object holds the proper cc
             $object = $inboxActivity->getObject();
-            if ($object !== null) {
+            if ($object !== null && is_object($object)) {
                 $sendTo = $object->getCC();
             }
         }
 
         $users = [];
+        $dbh = $this->main->getDatabase();
+        $cache = $this->main->getCache();
+        $connector = $this->main->getConnector();
 
         foreach ($sendTo as $receiver) {
             if ($receiver === '' || !is_string($receiver)) {
@@ -102,9 +104,23 @@ class Inbox implements \Federator\Api\FedUsers\FedUsersInterface
             }
 
             if (str_ends_with($receiver, '/followers')) {
-                $followers = $this->fetchAllFollowers($receiver, $host);
+                $actor = $inboxActivity->getAActor();
+                if ($actor === null || !is_string($actor)) {
+                    error_log("Inbox::post no actor found");
+                    continue;
+                }
+
+                // Extract username from the actor URL
+                $username = basename((string)(parse_url($actor, PHP_URL_PATH) ?? ''));
+                $domain = parse_url($actor, PHP_URL_HOST);
+                if ($username === null || $domain === null) {
+                    error_log("Inbox::post no username or domain found");
+                    continue;
+                }
+                $followers = \Federator\DIO\Followers::getFollowersByFedUser($dbh, $connector, $cache, $username . '@' . $domain);
+
                 if (is_array($followers)) {
-                    $users = array_merge($users, $followers);
+                    $users = array_merge($users, array_column($followers, 'id'));
                 }
             }
         }
@@ -116,7 +132,7 @@ class Inbox implements \Federator\Api\FedUsers\FedUsersInterface
                 continue;
             }
 
-            $this->postForUser($user, $inboxActivity);
+            $this->postForUser($dbh, $connector, $cache, $user, $inboxActivity);
         }
         return json_encode($inboxActivity, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT);
     }
@@ -124,17 +140,16 @@ class Inbox implements \Federator\Api\FedUsers\FedUsersInterface
     /**
      * handle post call for specific user
      *
+     * @param \mysqli $dbh database handle
+     * @param \Federator\Connector\Connector $connector connector to use
+     * @param \Federator\Cache\Cache|null $cache optional caching service
      * @param string $_user user to add data to inbox
      * @param \Federator\Data\ActivityPub\Common\Activity $inboxActivity the activity that we received
      * @return boolean response
      */
-    private function postForUser($_user, $inboxActivity)
+    private static function postForUser($dbh, $connector, $cache, $_user, $inboxActivity)
     {
         if (isset($_user)) {
-            $dbh = $this->main->getDatabase();
-            $cache = $this->main->getCache();
-            $connector = $this->main->getConnector();
-
             // get user
             $user = \Federator\DIO\User::getUserByName(
                 $dbh,
@@ -142,7 +157,7 @@ class Inbox implements \Federator\Api\FedUsers\FedUsersInterface
                 $connector,
                 $cache
             );
-            if ($user->id === null) {
+            if ($user === null || $user->id === null) {
                 error_log("Inbox::postForUser couldn't find user: $_user");
                 return false;
             }
@@ -158,64 +173,4 @@ class Inbox implements \Federator\Api\FedUsers\FedUsersInterface
 
         return true;
     }
-
-    /**
-     * fetch all followers from url and return the ones that belong to our server
-     *
-     * @param string $collectionUrl The url of f.e. the posters followers
-     * @param string $host our current host-url
-     * @return string[] the names of the followers that are hosted on our server
-     */
-    private static function fetchAllFollowers(string $collectionUrl, string $host): array
-    {
-        $users = [];
-
-        [$collectionResponse, $collectionInfo] = \Federator\Main::getFromRemote($collectionUrl, ['Accept: application/activity+json']);
-        if ($collectionInfo['http_code'] != 200) {
-            error_log("Inbox::fetchAllFollowers Failed to fetch follower collection metadata from $collectionUrl");
-            return [];
-        }
-
-        $collectionData = json_decode($collectionResponse, true);
-        $nextPage = $collectionData['first'] ?? $collectionData['current'] ?? null;
-
-        if (!isset($nextPage)) {
-            error_log("Inbox::fetchAllFollowers No 'first' or 'current' page in collection at $collectionUrl");
-            return [];
-        }
-
-        // Loop through all pages
-        while ($nextPage) {
-            [$pageResponse, $pageInfo] = \Federator\Main::getFromRemote($nextPage, ['Accept: application/activity+json']);
-            if ($pageInfo['http_code'] != 200) {
-                error_log("Inbox::fetchAllFollowers Failed to fetch follower page at $nextPage");
-                break;
-            }
-
-            $pageData = json_decode($pageResponse, true);
-            $items = $pageData['orderedItems'] ?? $pageData['items'] ?? [];
-
-            foreach ($items as $followerUrl) {
-                $parts = parse_url($followerUrl);
-                if (!isset($parts['host']) || !str_ends_with($parts['host'], $host)) {
-                    continue;
-                }
-
-                [$actorResponse, $actorInfo] = \Federator\Main::getFromRemote($followerUrl, ['Accept: application/activity+json']);
-                if ($actorInfo['http_code'] != 200) {
-                    error_log("Inbox::fetchAllFollowers Failed to fetch actor data for follower: $followerUrl");
-                    continue;
-                }
-
-                $actorData = json_decode($actorResponse, true);
-                if (isset($actorData['preferredUsername'])) {
-                    $users[] = $actorData['preferredUsername'];
-                }
-            }
-
-            $nextPage = $pageData['next'] ?? null;
-        }
-
-        return $users;
-    }
 }

php/federator/api/fedusers/outbox.php

@@ -66,15 +66,16 @@ class Outbox implements \Federator\Api\FedUsers\FedUsersInterface
         } else {
             $items = [];
         }
-        $host = $_SERVER['SERVER_NAME'];
+        $config = $this->main->getConfig();
-        $id = 'https://' . $host . '/users/' . $_user . '/outbox';
+        $domain = $config['generic']['externaldomain'];
+        $id = 'https://' . $domain . '/users/' . $_user . '/outbox';
         $outbox->setPartOf($id);
         $outbox->setID($id);
         if ($page !== '') {
             $id .= '?page=' . urlencode($page);
         }
         if ($page === '' || $outbox->count() == 0) {
-            $outbox->setFirst($id);
+            $outbox->setFirst($id . '?page=0');
             $outbox->setLast($id . '&min=0');
         }
         if (sizeof($items) > 0) {
@@ -84,7 +85,7 @@ class Outbox implements \Federator\Api\FedUsers\FedUsersInterface
             $outbox->setPrev($id . '&min=' . $oldestId);
         }
         $obj = $outbox->toObject();
-        return json_encode($obj);
+        return json_encode($obj, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT);
     }
 
     /**

php/federator/api/v1/dummy.php

@@ -20,12 +20,8 @@ class Dummy implements \Federator\Api\APIInterface
      */
     private $main;
 
-    /**
+    /** @var array<string, string> $message internal message to output */
-     * internal message to output
+    private $message = [];
-     *
-     * @var string $message
-     */
-    private $message = '';
 
     /**
      * constructor
@@ -47,9 +43,9 @@ class Dummy implements \Federator\Api\APIInterface
     public function exec($paths, $user): bool
     {
         // only for user with the 'publish' permission
-        // if ($user === false || $user->hasPermission('publish') === false) {
+        if ($user === false || $user->hasPermission('publish') === false) {
-        //     throw new \Federator\Exceptions\PermissionDenied();
+            throw new \Federator\Exceptions\PermissionDenied();
-        // }
+        }
         $method = $_SERVER["REQUEST_METHOD"];
         switch ($method) {
             case 'GET':
@@ -87,16 +83,13 @@ class Dummy implements \Federator\Api\APIInterface
      */
     public function getDummy()
     {
-        $dummyResponse = json_encode([
+        $this->message = [
             'r1' => '             (__)       ',
             'r2' => '      `------(oo)       ',
             'r3' => '       || __ (__)       ',
             'r4' => '       ||w  ||          ',
             'r5' => '                        '
-        ], JSON_PRETTY_PRINT);
+        ];
-        if ($dummyResponse !== false) {
-            $this->message = $dummyResponse;
-        }
         return true;
     }
 
@@ -117,6 +110,6 @@ class Dummy implements \Federator\Api\APIInterface
      */
     public function toJson()
     {
-        return $this->message;
+        return json_encode($this->message, JSON_PRETTY_PRINT) . "\n";
     }
 }

php/federator/api/v1/newcontent.php

@@ -71,12 +71,11 @@ class NewContent implements \Federator\Api\APIInterface
     /**
      * handle post call
      *
-     * @param string|null $_user user that triggered the post
+     * @param string|null $_user optional user that triggered the post
      * @return string|false response
      */
     public function post($_user)
     {
-        error_log("NewContent::post called with user: $_user");
         $_rawInput = file_get_contents('php://input');
 
         $allHeaders = getallheaders();
@@ -89,7 +88,9 @@ class NewContent implements \Federator\Api\APIInterface
         }
 
         $input = is_string($_rawInput) ? json_decode($_rawInput, true) : null;
-        $host = $_SERVER['SERVER_NAME'];
+
+        $config = $this->main->getConfig();
+        $domain = $config['generic']['externaldomain'];
         if (!is_array($input)) {
             error_log("NewContent::post Input wasn't of type array");
             return false;
@@ -98,7 +99,8 @@ class NewContent implements \Federator\Api\APIInterface
         if (isset($allHeaders['X-Sender'])) {
             $newActivity = $this->main->getConnector()->jsonToActivity($input);
         } else {
-            $newActivity = \Federator\Data\ActivityPub\Factory::newActivityFromJson($input);
+            error_log("NewContent::post No X-Sender header found");
+            return false;
         }
 
         if ($newActivity === false) {
@@ -106,27 +108,26 @@ class NewContent implements \Federator\Api\APIInterface
             return false;
         }
 
-        $sendTo = $newActivity->getCC();
+        $dbh = $this->main->getDatabase();
-        if ($newActivity->getType() === 'Undo') {
+        $cache = $this->main->getCache();
-            $object = $newActivity->getObject();
+        $connector = $this->main->getConnector();
-            if ($object !== null) {
+
-                $sendTo = $object->getCC();
+        if (!isset($_user)) {
-            }
+            $user = $newActivity->getAActor(); // url of the sender https://contentnation.net/username
+            $user = str_replace(
+                $domain,
+                '',
+                $user
+            ); // retrieve only the last part of the url
+        } else {
+            $user = $dbh->real_escape_string($_user);
         }
 
         $users = [];
 
-        foreach ($sendTo as $receiver) {
+        $followers = $this->fetchAllFollowers($dbh, $connector, $cache, $user);
-            if ($receiver === '' || !is_string($receiver)) {
+        if (!empty($followers)) {
-                continue;
+            $users = array_merge($users, $followers);
-            }
-
-            if (str_ends_with($receiver, '/followers')) {
-                $followers = $this->fetchAllFollowers($receiver, $host);
-                if (is_array($followers)) {
-                    $users = array_merge($users, $followers);
-                }
-            }
         }
 
         if (empty($users)) { // todo remove after proper implementation, debugging for now
@@ -147,7 +148,7 @@ class NewContent implements \Federator\Api\APIInterface
                 continue;
             }
 
-            $this->postForUser($user, $newActivity);
+            $this->postForUser($dbh, $connector, $cache, $user, $newActivity);
         }
 
         return json_encode($newActivity, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT);
@@ -156,28 +157,33 @@ class NewContent implements \Federator\Api\APIInterface
     /**
      * handle post call for specific user
      *
+     * @param \mysqli $dbh @unused-param
+     *          database handle
+     * @param \Federator\Connector\Connector $connector
+     *          connector to fetch use with
+     * @param \Federator\Cache\Cache|null $cache
+     *          optional caching service
      * @param string $_user user that triggered the post
      * @param \Federator\Data\ActivityPub\Common\Activity $newActivity the activity that we received
      * @return boolean response
      */
-    private function postForUser($_user, $newActivity)
+    private static function postForUser($dbh, $connector, $cache, $_user, $newActivity)
     {
-        if (isset($_user)) {
+        if (!isset($_user)) {
-            $dbh = $this->main->getDatabase();
+            error_log("NewContent::postForUser no user given");
-            $cache = $this->main->getCache();
+            return false;
-            $connector = $this->main->getConnector();
+        }
 
-            // get user
+        // get user
-            $user = \Federator\DIO\User::getUserByName(
+        $user = \Federator\DIO\User::getUserByName(
-                $dbh,
+            $dbh,
-                $_user,
+            $_user,
-                $connector,
+            $connector,
-                $cache
+            $cache
-            );
+        );
-            if ($user->id === null) {
+        if ($user->id === null) {
-                error_log("NewContent::postForUser couldn't find user: $_user");
+            error_log("NewContent::postForUser couldn't find user: $_user");
-                return false;
+            return false;
-            }
         }
 
         $rootDir = $_SERVER['DOCUMENT_ROOT'] . '../';
@@ -194,58 +200,32 @@ class NewContent implements \Federator\Api\APIInterface
     /**
      * fetch all followers from url and return the ones that belong to our server
      *
-     * @param string $collectionUrl The url of f.e. the posters followers
+     * @param \mysqli $dbh
-     * @param string $host our current host-url
+     *          database handle
+     * @param \Federator\Connector\Connector $connector
+     *          connector to fetch use with
+     * @param \Federator\Cache\Cache|null $cache
+     *          optional caching service
+     * @param string $userId The id of the user
      * @return string[] the names of the followers that are hosted on our server
      */
-    private static function fetchAllFollowers(string $collectionUrl, string $host): array
+    private static function fetchAllFollowers($dbh, $connector, $cache, string $userId): array
     {
+        if (empty($userId)) {
+            return [];
+        }
+
         $users = [];
 
-        [$collectionResponse, $collectionInfo] = \Federator\Main::getFromRemote($collectionUrl, ['Accept: application/activity+json']);
+        $apFollowers = \Federator\DIO\Followers::getFollowersByUser(
-        if ($collectionInfo['http_code'] != 200) {
+            $dbh,
-            error_log("NewContent::fetchAllFollowers Failed to fetch follower collection metadata from $collectionUrl");
+            $userId,
-            return [];
+            $connector,
-        }
+            cache: $cache,
+        );
 
-        $collectionData = json_decode($collectionResponse, true);
+        foreach ($apFollowers as $follower) {
-        $nextPage = $collectionData['first'] ?? $collectionData['current'] ?? null;
+            $users[] = $follower->id;
-
-        if (!isset($nextPage)) {
-            error_log("NewContent::fetchAllFollowers No 'first' or 'current' page in collection at $collectionUrl");
-            return [];
-        }
-
-        // Loop through all pages
-        while ($nextPage) {
-            [$pageResponse, $pageInfo] = \Federator\Main::getFromRemote($nextPage, ['Accept: application/activity+json']);
-            if ($pageInfo['http_code'] != 200) {
-                error_log("NewContent::fetchAllFollowers Failed to fetch follower page at $nextPage");
-                break;
-            }
-
-            $pageData = json_decode($pageResponse, true);
-            $items = $pageData['orderedItems'] ?? $pageData['items'] ?? [];
-
-            foreach ($items as $followerUrl) {
-                $parts = parse_url($followerUrl);
-                if (!isset($parts['host']) || !str_ends_with($parts['host'], $host)) {
-                    continue;
-                }
-
-                [$actorResponse, $actorInfo] = \Federator\Main::getFromRemote($followerUrl, ['Accept: application/activity+json']);
-                if ($actorInfo['http_code'] != 200) {
-                    error_log("NewContent::fetchAllFollowers Failed to fetch actor data for follower: $followerUrl");
-                    continue;
-                }
-
-                $actorData = json_decode($actorResponse, true);
-                if (isset($actorData['preferredUsername'])) {
-                    $users[] = $actorData['preferredUsername'];
-                }
-            }
-
-            $nextPage = $pageData['next'] ?? null;
         }
 
         return $users;

php/federator/api/wellknown.php

@@ -44,8 +44,10 @@ class WellKnown implements APIInterface
      */
     private function hostMeta()
     {
+        $config = $this->main->getConfig();
+        $domain = $config['generic']['externaldomain'];
         $data = [
-          'fqdn' => $_SERVER['SERVER_NAME']
+          'fqdn' => $domain
         ];
         $this->response = $this->main->renderTemplate('host-meta.xml', $data);
         return true;

php/federator/api/wellknown/nodeinfo.php

@@ -45,8 +45,10 @@ class NodeInfo
      */
     public function exec($paths)
     {
+        $config = $this->main->getConfig();
+        $domain = $config['generic']['externaldomain'];
         $data = [
-            'fqdn' => $_SERVER['SERVER_NAME']
+            'fqdn' => $domain
         ];
         $template = null;
         if (sizeof($paths) == 2 && $paths[0] === '.well-known' && $paths[1] === 'nodeinfo') {

php/federator/cache/cache.php

@@ -17,7 +17,7 @@ interface Cache extends \Federator\Connector\Connector
      * save remote followers of user
      *
      * @param string $user user name
-     * @param \Federator\Data\ActivityPub\Common\APObject[]|false $followers user followers
+     * @param \Federator\Data\FedUser[]|false $followers user followers
      * @return void
      */
     public function saveRemoteFollowersOfUser($user, $followers);
@@ -48,6 +48,15 @@ interface Cache extends \Federator\Connector\Connector
      */
     public function saveRemoteUserByName($_name, $user);
 
+    /**
+     * save remote federation user by given name
+     *
+     * @param string $_name user/profile name
+     * @param \Federator\Data\FedUser $user user data
+     * @return void
+     */
+    public function saveRemoteFedUserByName(string $_name, \Federator\Data\FedUser $user);
+
     /**
      * save remote user by given session
      *
@@ -67,6 +76,14 @@ interface Cache extends \Federator\Connector\Connector
      */
     public function savePublicKey(string $keyId, string $publicKeyPem);
 
+    /**
+     * get remote federation user by given name
+     *
+     * @param string $_name user/profile name
+     * @return \Federator\Data\FedUser | false
+     */
+    public function getRemoteFedUserByName(string $_name);
+
     /**
      * Retrieve the public key for a given keyId
      *

php/federator/connector/connector.php

@@ -18,7 +18,7 @@ interface Connector
      *
      * @param string $id user id
 
-     * @return \Federator\Data\ActivityPub\Common\APObject[]|false
+     * @return \Federator\Data\FedUser[]|false
      */
     public function getRemoteFollowersOfUser($id);
 

php/federator/data/activitypub/common/Announce.php

@@ -25,8 +25,6 @@ class Announce extends Activity
     {
         $return = parent::toObject();
         $return['type'] = 'Announce';
-        // overwrite id from url
-        $return['id'] = $this->getURL();
         return $return;
     }
 

php/federator/data/activitypub/common/Undo.php

@@ -25,8 +25,6 @@ class Undo extends Activity
     {
         $return = parent::toObject();
         $return['type'] = 'Undo';
-        // overwrite id from url
-        $return['id'] = $this->getURL();
         return $return;
     }
 

php/federator/data/activitypub/common/accept.php

@@ -0,0 +1,18 @@
+<?php
+/**
+ * SPDX-FileCopyrightText: 2024 Sascha Nitsch (grumpydeveloper) https://contentnation.net/@grumpydevelop
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ *
+ * @author Yannis Vogel (vogeldevelopment)
+ **/
+
+namespace Federator\Data\ActivityPub\Common;
+
+class Accept extends Activity
+{
+    public function __construct()
+    {
+      parent::__construct('Accept');
+      parent::addContext('https://www.w3.org/ns/activitystreams');
+    }
+}

php/federator/data/activitypub/common/activity.php

@@ -74,6 +74,7 @@ class Activity extends APObject
     {
         if (array_key_exists('actor', $json)) {
             $this->actor = $json['actor'];
+            $this->aactor = $json['actor'];
             unset($json['actor']);
         }
         if (!parent::fromJson($json)) {
@@ -102,7 +103,7 @@ class Activity extends APObject
     /**
      * get Child Object
      *
-     * @return APObject|null
+     * @return APObject|string|null
      */
     public function getObject()
     {

php/federator/data/activitypub/common/apobject.php

@@ -27,7 +27,7 @@ class APObject implements \JsonSerializable
     /**
      * child object
      *
-     * @var APObject|null $object
+     * @var APObject|string|null $object
      */
     private $object = null;
 
@@ -358,7 +358,7 @@ class APObject implements \JsonSerializable
     /**
      * get child object
      *
-     * @return APObject|null child object
+     * @return APObject|string|null child object
      */
     public function getObject()
     {
@@ -750,8 +750,8 @@ class APObject implements \JsonSerializable
         if (array_key_exists('mediaType', $json)) {
             $this->mediaType = $json['mediaType'];
         }
-        if (array_key_exists('object', $json)) {
+        if (array_key_exists('object', $json)) { // some actPub servers send strings in the object field
-            $this->object = \Federator\Data\ActivityPub\Factory::newFromJson($json['object'], "");
+            $this->object = is_array($json['object']) ? \Federator\Data\ActivityPub\Factory::newFromJson($json['object'], "") : $json['object'];
         }
         if (array_key_exists('sensitive', $json)) {
             $this->sensitive = $json['sensitive'];
@@ -890,7 +890,7 @@ class APObject implements \JsonSerializable
             $return['mediaType'] = $this->mediaType;
         }
         if ($this->object !== null) {
-            $return['object'] = $this->object->toObject();
+            $return['object'] = is_string($this->object) ? $this->object : $this->object->toObject();
         }
         if ($this->atomURI !== '') {
             $return['atomUri'] = $this->atomURI;

php/federator/data/activitypub/common/delete.php

@@ -0,0 +1,54 @@
+<?php
+/**
+ * SPDX-FileCopyrightText: 2024 Sascha Nitsch (grumpydeveloper) https://contentnation.net/@grumpydevelop
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ *
+ * @author Yannis Vogel (vogeldevelopment)
+ **/
+
+namespace Federator\Data\ActivityPub\Common;
+
+class Delete extends Activity
+{
+    /**
+     * object overwrite
+     * @var string
+     */
+    private $object = "";
+  
+    public function setFObject(string $object): void
+    {
+      $this->object = $object;
+    }
+  
+    public function __construct()
+    {
+      parent::__construct('Delete');
+      parent::addContext('https://www.w3.org/ns/activitystreams');
+    }
+  
+    /**
+     * create from json/array
+     * @param mixed $json
+     */
+    public function fromJson($json): bool
+    {
+      if (array_key_exists('object', $json)) {
+        $this->object = $json['object'];
+        unset($json['object']);
+      }
+      return parent::fromJson($json);
+    }
+    /**
+     * convert internal state to php array
+     * @return array<string,mixed>
+     */
+    public function toObject()
+    {
+      $return = parent::toObject();
+      if ($this->object !== "") {
+        $return['object'] = $this->object;
+      }
+      return $return;
+    }
+}

php/federator/data/activitypub/common/follow.php

@@ -0,0 +1,50 @@
+<?php
+/**
+ * SPDX-FileCopyrightText: 2024 Sascha Nitsch (grumpydeveloper) https://contentnation.net/@grumpydevelop
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ *
+ * @author Yannis Vogel (vogeldevelopment)
+ **/
+
+namespace Federator\Data\ActivityPub\Common;
+
+class Follow extends Activity
+{
+    /**
+     * object overwrite
+     * @var string
+     */
+    private $object = "";
+
+    public function setFObject(string $object): void
+    {
+        $this->object = $object;
+    }
+
+    public function __construct()
+    {
+        parent::__construct("Follow");
+        parent::addContext('https://www.w3.org/ns/activitystreams');
+    }
+
+    public function fromJson($json): bool
+    {
+        if (array_key_exists('object', $json)) {
+            $this->object = $json['object'];
+            unset($json['object']);
+        }
+        return parent::fromJson($json);
+    }
+    /**
+     * convert internal state to php array
+     * @return array<string,mixed>
+     */
+    public function toObject()
+    {
+        $return = parent::toObject();
+        if ($this->object !== "") {
+            $return['object'] = $this->object;
+        }
+        return $return;
+    }
+}

php/federator/data/activitypub/common/reject.php

@@ -0,0 +1,18 @@
+<?php
+/**
+ * SPDX-FileCopyrightText: 2024 Sascha Nitsch (grumpydeveloper) https://contentnation.net/@grumpydevelop
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ *
+ * @author Yannis Vogel (vogeldevelopment)
+ **/
+
+namespace Federator\Data\ActivityPub\Common;
+
+class Reject extends Activity
+{
+    public function __construct()
+    {
+      parent::__construct('Reject');
+      parent::addContext('https://www.w3.org/ns/activitystreams');
+    }
+}

php/federator/data/activitypub/factory.php

@@ -31,6 +31,9 @@ class Factory
         }
         $return = null;
         switch ($json['type']) {
+            case 'Announce':
+                $return = new Common\Announce();
+                break;
             case 'Article':
                 $return = new Common\Article();
                 break;
@@ -39,10 +42,10 @@ class Factory
                 break;
             case 'Event':
                 $return = new Common\Event();
-                break;
+                break;*/
             case 'Follow':
                 $return = new Common\Follow();
-                break;*/
+                break;
             case 'Image':
                 $return = new Common\Image();
                 break;
@@ -83,21 +86,24 @@ class Factory
         }
         //$return = false;
         switch ($json['type']) {
-            /* case 'Accept':
+            case 'Accept':
                 $return = new Common\Accept();
-                break; */
+                break;
             case 'Announce':
                 $return = new Common\Announce();
                 break;
             case 'Create':
                 $return = new Common\Create();
                 break;
-            /*case 'Delete':
+            case 'Delete':
                 $return = new Common\Delete();
                 break;
             case 'Follow':
                 $return = new Common\Follow();
-                break;*/
+                break;
+            case 'Reject':
+                $return = new Common\Reject();
+                break;
             case 'Undo':
                 $return = new Common\Undo();
                 break;

php/federator/data/feduser.php

@@ -0,0 +1,151 @@
+<?php
+/**
+ * SPDX-FileCopyrightText: 2024 Sascha Nitsch (grumpydeveloper) https://contentnation.net/@grumpydevelop
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ *
+ * @author Yannis Vogel (vogeldevelopment)
+ **/
+
+namespace Federator\Data;
+
+/**
+ * storage class for user attributes
+ */
+class FedUser
+{
+    /**
+     * user id
+     *
+     * @var string $id
+     */
+    public $id;
+
+    /**
+     * user url
+     *
+     * @var string $actorURL
+     */
+    public $actorURL;
+
+    /**
+     * user name
+     *
+     * @var string $name
+     */
+    public $name = '';
+
+    /**
+     * user public key
+     *
+     * @var string $publicKey
+     */
+    public $publicKey;
+
+    /**
+     * summary for user/profile
+     *
+     * @var string $summary
+     */
+    public $summary = '';
+
+    /**
+     * type of user (person/group)
+     *
+     * @var string $type
+     */
+    public $type = 'Person';
+
+    /**
+     * inbox URL
+     *
+     * @var string $inboxURL
+     */
+    public $inboxURL;
+
+    /**
+     * shared inbox URL
+     *
+     * @var string $sharedInboxURL
+     */
+    public $sharedInboxURL;
+
+    /**
+     * followers URL
+     *
+     * @var string $followersURL
+     */
+    public $followersURL;
+
+    /**
+     * following URL
+     *
+     * @var string $followingURL
+     */
+    public $followingURL;
+
+    /**
+     * public key ID
+     *
+     * @var string $publicKeyId
+     */
+    public $publicKeyId;
+
+    /**
+     * outbox URL
+     *
+     * @var string $outboxURL
+     */
+    public $outboxURL;
+
+    /**
+     * create new user object from json string
+     *
+     * @param string $input input string
+     * @return FedUser|false
+     */
+    public static function createFromJson($input)
+    {
+        $data = json_decode($input, true);
+        if ($data === null) {
+            return false;
+        }
+        $user = new FedUser();
+        $user->id = $data['id'] ?? '';
+        $user->actorURL = $data['actorURL'] ?? '';
+        $user->name = $data['name'] ?? '';
+        $user->publicKey = $data['publicKey'] ?? '';
+        $user->summary = $data['summary'] ?? '';
+        $user->type = $data['type'] ?? 'Person';
+        $user->inboxURL = $data['inbox'] ?? '';
+        $user->sharedInboxURL = $data['sharedInbox'] ?? '';
+        $user->followersURL = $data['followers'] ?? '';
+        $user->followingURL = $data['following'] ?? '';
+        $user->publicKeyId = $data['publicKeyId'] ?? '';
+        $user->outboxURL = $data['outbox'] ?? '';
+        return $user;
+    }
+
+    /**
+     * convert internal data to json string
+     *
+     * @return string
+     */
+    public function toJson()
+    {
+        $data = [
+            'id' => $this->id,
+            'actorURL' => $this->actorURL,
+            'name' => $this->name,
+            'publicKey' => $this->publicKey,
+            'summary' => $this->summary,
+            'type' => $this->type,
+            'inbox' => $this->inboxURL,
+            'sharedInbox' => $this->sharedInboxURL,
+            'followers' => $this->followersURL,
+            'following' => $this->followingURL,
+            'publicKeyId' => $this->publicKeyId,
+            'outbox' => $this->outboxURL,
+        ];
+        return json_encode($data) ?: '';
+    }
+}

php/federator/dio/feduser.php

@@ -0,0 +1,242 @@
+<?php
+/**
+ * SPDX-FileCopyrightText: 2024 Sascha Nitsch (grumpydeveloper) https://contentnation.net/@grumpydevelop
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ *
+ * @author Yannis Vogel (vogeldevelopment)
+ **/
+
+namespace Federator\DIO;
+
+/**
+ * IO functions related to fedUsers
+ */
+class FedUser
+{
+    /**
+     * add local user based on given user object received from remote service
+     * @param \mysqli $dbh database handle
+     * @param \Federator\Data\FedUser $user user object to use
+     * @param string $_user user/profile name
+     * @return void
+     */
+    protected static function addLocalUser($dbh, $user, $_user)
+    {
+        // check if it is timed out user
+        $sql = 'select unix_timestamp(`validuntil`) from fedusers where id=?';
+        $stmt = $dbh->prepare($sql);
+        if ($stmt === false) {
+            throw new \Federator\Exceptions\ServerError();
+        }
+        $stmt->bind_param("s", $_user);
+        $validuntil = 0;
+        $ret = $stmt->bind_result($validuntil);
+        $stmt->execute();
+        if ($ret) {
+            $stmt->fetch();
+        }
+        $stmt->close();
+        if ($validuntil == 0) {
+            $sql = 'insert into fedusers (id, url, name, publickey, summary, type, inboxurl, sharedinboxurl,';
+            $sql .= ' followersurl, followingurl, publickeyid, outboxurl, validuntil)';
+            $sql .= ' values (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, now() + interval 1 day)';
+            $stmt = $dbh->prepare($sql);
+            if ($stmt === false) {
+                throw new \Federator\Exceptions\ServerError();
+            }
+            $stmt->bind_param(
+                "ssssssssssss",
+                $_user,
+                $user->actorURL,
+                $user->name,
+                $user->publicKey,
+                $user->summary,
+                $user->type,
+                $user->inboxURL,
+                $user->sharedInboxURL,
+                $user->followersURL,
+                $user->followingURL,
+                $user->publicKeyId,
+                $user->outboxURL
+            );
+        } else {
+            // update to existing user
+            $sql = 'update fedusers set validuntil=now() + interval 1 day, url=?, name=?, publickey=?, summary=?,';
+            $sql .= ' type=?, inboxurl=?, sharedinboxurl=?, followersurl=?, followingurl=?, publickeyid=?, outboxurl=?';
+            $sql .= ' where id=?';
+            $stmt = $dbh->prepare($sql);
+            if ($stmt === false) {
+                throw new \Federator\Exceptions\ServerError();
+            }
+            $stmt->bind_param(
+                "ssssssssssss",
+                $user->actorURL,
+                $user->name,
+                $user->publicKey,
+                $user->summary,
+                $user->type,
+                $user->inboxURL,
+                $user->sharedInboxURL,
+                $user->followersURL,
+                $user->followingURL,
+                $user->publicKeyId,
+                $user->outboxURL,
+                $_user
+            );
+        }
+        try {
+            $stmt->execute();
+            $stmt->close();
+            $user->id = $_user;
+        } catch (\mysqli_sql_exception $e) {
+            error_log($sql);
+            error_log(print_r($user, true));
+            error_log($e->getMessage());
+        }
+    }
+
+    /**
+     * extend the given user with internal data
+     * @param \mysqli $dbh database  handle
+     * @param \Federator\Data\FedUser $user user to extend
+     * @param string $_user user/profile name
+     */
+    protected static function extendUser(\mysqli $dbh, \Federator\Data\FedUser $user, $_user): void
+    {
+        $sql = 'select id,unix_timestamp(`validuntil`) from fedusers where id=?';
+        $stmt = $dbh->prepare($sql);
+        if ($stmt === false) {
+            throw new \Federator\Exceptions\ServerError();
+        }
+        $stmt->bind_param("s", $_user);
+        $validuntil = 0;
+        $ret = $stmt->bind_result($user->id, $validuntil);
+        $stmt->execute();
+        if ($ret) {
+            $stmt->fetch();
+        }
+        $stmt->close();
+        // if a new user, create own database entry with additionally needed info
+        if ($user->id === null || $validuntil < time()) {
+            self::addLocalUser($dbh, $user, $_user);
+        }
+
+        // no further processing for now
+    }
+
+    /**
+     * get user by name
+     *
+     * @param \mysqli $dbh
+     *          database handle
+     * @param string $_name
+     *          user name
+     * @param \Federator\Cache\Cache|null $cache
+     *          optional caching service
+     * @return \Federator\Data\FedUser
+     */
+    public static function getUserByName($dbh, $_name, $cache)
+    {
+        $user = false;
+
+        // ask cache
+        if ($cache !== null) {
+            $user = $cache->getRemoteFedUserByName($_name);
+        }
+        if ($user !== false) {
+            return $user;
+        }
+        // check our db
+        $sql = 'select id, url, name, publickey, summary, type, inboxurl, sharedinboxurl, followersurl,';
+        $sql .= ' followingurl,publickeyid,outboxurl';
+        $sql .= ' from fedusers where id=? and validuntil>=now()';
+        $stmt = $dbh->prepare($sql);
+        if ($stmt === false) {
+            throw new \Federator\Exceptions\ServerError();
+        }
+        $stmt->bind_param("s", $_name);
+        $user = new \Federator\Data\FedUser();
+        $ret = $stmt->bind_result(
+            $user->id,
+            $user->actorURL,
+            $user->name,
+            $user->publicKey,
+            $user->summary,
+            $user->type,
+            $user->inboxURL,
+            $user->sharedInboxURL,
+            $user->followersURL,
+            $user->followingURL,
+            $user->publicKeyId,
+            $user->outboxURL
+        );
+        $stmt->execute();
+        if ($ret) {
+            $stmt->fetch();
+        }
+        $stmt->close();
+
+        if ($user->id === null) {
+            // check if its a federated user with username@domain.ending
+            if (preg_match("/^([^@]+)@(.*)$/", $_name, $matches) == 1) {
+                // make webfinger request
+                $remoteURL = 'https://' . $matches[2] . '/.well-known/webfinger?resource=acct:' . urlencode($_name);
+                $headers = ['Accept: application/activity+json'];
+                [$response, $info] = \Federator\Main::getFromRemote($remoteURL, $headers);
+                if ($info['http_code'] != 200) {
+                    throw new \Federator\Exceptions\ServerError();
+                }
+                $r = json_decode($response, true);
+                if ($r === false || $r === null || !is_array($r)) {
+                    throw new \Federator\Exceptions\ServerError();
+                }
+                // get the webwinger user url and fetch the user
+                if (isset($r['links'])) {
+                    foreach ($r['links'] as $link) {
+                        if (isset($link['rel']) && $link['rel'] === 'self') {
+                            $remoteURL = $link['href'];
+                            break;
+                        }
+                    }
+                }
+                if (!isset($remoteURL)) {
+                    throw new \Federator\Exceptions\ServerError();
+                }
+                // fetch the user
+                $headers = ['Accept: application/activity+json'];
+                [$response, $info] = \Federator\Main::getFromRemote($remoteURL, $headers);
+                if ($info['http_code'] != 200) {
+                    throw new \Federator\Exceptions\ServerError();
+                }
+                $r = json_decode($response, true);
+                if ($r === false || $r === null || !is_array($r)) {
+                    throw new \Federator\Exceptions\ServerError();
+                }
+                $r['publicKeyId'] = $r['publicKey']['id'];
+                $r['publicKey'] = $r['publicKey']['publicKeyPem'];
+                if (isset($r['endpoints'])) {
+                    if (isset($r['endpoints']['sharedInbox'])) {
+                        $r['sharedInbox'] = $r['endpoints']['sharedInbox'];
+                    }
+                }
+                $r['actorURL'] = $remoteURL;
+                $data = json_encode($r);
+                if ($data === false) {
+                    throw new \Federator\Exceptions\ServerError();
+                }
+                $user = \Federator\Data\FedUser::createFromJson($data);
+            }
+        }
+
+        if ($cache !== null && $user !== false) {
+            if ($user->id === null && $user->actorURL !== null) {
+                self::addLocalUser($dbh, $user, $_name);
+            }
+            $cache->saveRemoteFedUserByName($_name, $user);
+        }
+        if ($user === false) {
+            throw new \Federator\Exceptions\ServerError();
+        }
+        return $user;
+    }
+}

php/federator/dio/followers.php

@@ -13,11 +13,10 @@ namespace Federator\DIO;
  */
 class Followers
 {
-
     /**
      * get followers of user
      *
-     * @param \mysqli $dbh @unused-param
+     * @param \mysqli $dbh
      *          database handle
      * @param string $id
      *          user id
@@ -25,7 +24,7 @@ class Followers
      *          connector to fetch use with
      * @param \Federator\Cache\Cache|null $cache
      *          optional caching service
-     * @return \Federator\Data\ActivityPub\Common\APObject[]
+     * @return \Federator\Data\FedUser[]
      */
     public static function getFollowersByUser($dbh, $id, $connector, $cache)
     {
@@ -37,7 +36,29 @@ class Followers
             }
         }
         $followers = [];
-        // TODO: check our db
+        $sql = 'select source_user from follows where target_user = ?';
+        $stmt = $dbh->prepare($sql);
+        if ($stmt === false) {
+            throw new \Federator\Exceptions\ServerError();
+        }
+        $stmt->bind_param("s", $id);
+        $stmt->execute();
+        $followerIds = [];
+        $stmt->bind_result($sourceUser);
+        while ($stmt->fetch()) {
+            $followerIds[] = $sourceUser;
+        }
+        $stmt->close();
+        foreach ($followerIds as $followerId) {
+            $user = \Federator\DIO\FedUser::getUserByName(
+                $dbh,
+                $followerId,
+                $cache,
+            );
+            if ($user !== false && $user->id !== null) {
+                $followers[] = $user;
+            }
+        }
 
         if ($followers === []) {
             // ask connector for user-id
@@ -52,4 +73,263 @@ class Followers
         }
         return $followers;
     }
+    /**
+     * get followers of user
+     *
+     * @param \mysqli $dbh
+     *          database handle
+     * @param \Federator\Connector\Connector $connector
+     *          connector to fetch use with
+     * @param \Federator\Cache\Cache|null $cache
+     *          optional caching service
+     * @param string $id
+     *          user id
+     * @return \Federator\Data\User[]
+     */
+
+    public static function getFollowersByFedUser($dbh, $connector, $cache, $id)
+    {
+        $followers = [];
+
+        $sql = 'select source_user from follows where target_user = ?';
+        $stmt = $dbh->prepare($sql);
+        if ($stmt === false) {
+            throw new \Federator\Exceptions\ServerError();
+        }
+        $stmt->bind_param("s", $id);
+        $stmt->execute();
+        $followerIds = [];
+        $stmt->bind_result($sourceUser);
+        while ($stmt->fetch()) {
+            $followerIds[] = $sourceUser;
+        }
+        foreach ($followerIds as $followerId) {
+            $user = \Federator\DIO\User::getUserByName(
+                $dbh,
+                $followerId,
+                $connector,
+                $cache
+            );
+            if ($user !== false && $user->id !== null) {
+                $followers[] = $user;
+            }
+        }
+        return $followers;
+    }
+
+    /**
+     * send follow request
+     *
+     * @param \mysqli $dbh database handle
+     * @param \Federator\Connector\Connector $connector connector to use
+     * @param \Federator\Cache\Cache|null $cache optional caching service
+     * @param string $_user source user
+     * @param string $_targetUser target user id
+     * @param string $host the host for generating the follow ID
+     * @return string|false the generated follow ID on success, false on failure
+     */
+    public static function sendFollowRequest($dbh, $connector, $cache, $_user, $_targetUser, $host)
+    {
+        if ($dbh === false) {
+            throw new \Federator\Exceptions\ServerError();
+        }
+        $user = \Federator\DIO\User::getUserByName(
+            $dbh,
+            $_user,
+            $connector,
+            $cache
+        );
+        if ($user === false || $user->id === null) {
+            throw new \Federator\Exceptions\FileNotFound();
+        }
+
+        $fedUser = \Federator\DIO\FedUser::getUserByName(
+            $dbh,
+            $_targetUser,
+            $cache
+        );
+        if ($fedUser === false || $fedUser->actorURL === null) {
+            throw new \Federator\Exceptions\FileNotFound();
+        }
+
+        $sourceUser = $user->id;
+        $idUrl = self::addFollow($dbh, $sourceUser, $fedUser->id, $host);
+        if ($idUrl === false) {
+            return false; // Failed to add follow
+        }
+        $followObj = new \Federator\Data\ActivityPub\Common\Follow();
+        $sourceUserUrl = 'https://' . $host . '/' . $sourceUser;
+        $followObj->setFObject($fedUser->actorURL);
+        $followObj->setAActor($sourceUserUrl);
+        $followObj->setID($idUrl);
+
+        // Send the Follow activity
+        $inboxUrl = $fedUser->inboxURL;
+
+        $json = json_encode($followObj, JSON_UNESCAPED_SLASHES);
+
+        if ($json === false) {
+            self::removeFollow($dbh, $sourceUser, $fedUser->id);
+            throw new \Exception('Failed to encode JSON: ' . json_last_error_msg());
+        }
+        $digest = 'SHA-256=' . base64_encode(hash('sha256', $json, true));
+        $date = gmdate('D, d M Y H:i:s') . ' GMT';
+        $parsed = parse_url($inboxUrl);
+        if ($parsed === false) {
+            self::removeFollow($dbh, $sourceUser, $fedUser->id);
+            throw new \Exception('Failed to parse URL: ' . $inboxUrl);
+        }
+
+        if (!isset($parsed['host']) || !isset($parsed['path'])) {
+            self::removeFollow($dbh, $sourceUser, $fedUser->id);
+            throw new \Exception('Invalid inbox URL: missing host or path');
+        }
+        $extHost = $parsed['host'];
+        $path = $parsed['path'];
+
+        // Build the signature string
+        $signatureString = "(request-target): post {$path}\n" .
+            "host: {$extHost}\n" .
+            "date: {$date}\n" .
+            "digest: {$digest}";
+
+        // Get rsa private key
+        $privateKey = \Federator\DIO\User::getrsaprivate($dbh, $user->id); // OR from DB
+        if ($privateKey === false) {
+            self::removeFollow($dbh, $sourceUser, $fedUser->id);
+            throw new \Exception('Failed to get private key');
+        }
+        $pkeyId = openssl_pkey_get_private($privateKey);
+
+        if ($pkeyId === false) {
+            self::removeFollow($dbh, $sourceUser, $fedUser->id);
+            throw new \Exception('Invalid private key');
+        }
+
+        openssl_sign($signatureString, $signature, $pkeyId, OPENSSL_ALGO_SHA256);
+        $signature_b64 = base64_encode($signature);
+
+        // Build keyId (public key ID from your actor object)
+        $keyId = 'https://' . $host . '/' . $user->id . '#main-key';
+
+        $signatureHeader = 'keyId="' . $keyId . '",algorithm="rsa-sha256",headers="(request-target) host date digest",signature="' . $signature_b64 . '"';
+
+        $ch = curl_init($inboxUrl);
+        if ($ch === false) {
+            self::removeFollow($dbh, $sourceUser, $fedUser->id);
+            throw new \Exception('Failed to initialize cURL');
+        }
+        $headers = [
+            'Host: ' . $extHost,
+            'Date: ' . $date,
+            'Digest: ' . $digest,
+            'Content-Type: application/activity+json',
+            'Signature: ' . $signatureHeader,
+            'Accept: application/activity+json',
+        ];
+
+        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
+        curl_setopt($ch, CURLOPT_POST, true);
+        curl_setopt($ch, CURLOPT_POSTFIELDS, $json);
+        curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
+        $response = curl_exec($ch);
+        curl_close($ch);
+
+        // Log the response for debugging if needed
+        if ($response === false) {
+            self::removeFollow($dbh, $sourceUser, $fedUser->id);
+            throw new \Exception("Failed to send Follow activity: " . curl_error($ch));
+        } else {
+            $httpcode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
+            if ($httpcode != 200 && $httpcode != 202) {
+                self::removeFollow($dbh, $sourceUser, $fedUser->id);
+                throw new \Exception("Unexpected HTTP code $httpcode: $response");
+            }
+        }
+        return $idUrl;
+    }
+
+    /**
+     * add follow
+     *
+     * @param \mysqli $dbh database handle
+     * @param string $sourceUser source user id
+     * @param string $targetUserId target user id
+     * @param string $host the host for generating the follow ID
+     * @return string|false the generated follow ID on success, false on failure
+     */
+    public static function addFollow($dbh, $sourceUser, $targetUserId, $host)
+    {
+        // Check if we already follow this user
+        $sql = 'select id from follows where source_user = ? and target_user = ?';
+        $stmt = $dbh->prepare($sql);
+        if ($stmt === false) {
+            throw new \Federator\Exceptions\ServerError();
+        }
+        $stmt->bind_param("ss", $sourceUser, $targetUserId);
+        $foundId = 0;
+        $ret = $stmt->bind_result($foundId);
+        $stmt->execute();
+        if ($ret) {
+            $stmt->fetch();
+        }
+        $stmt->close();
+        if ($foundId != 0) {
+            return false; // Already following this user
+        }
+
+        // Generate a unique ID for the follow relationship
+        do {
+            $id = bin2hex(openssl_random_pseudo_bytes(16));
+            $idurl = 'https://' . $host . '/' . $sourceUser . '/' . $id;
+
+            // Check if the generated ID is unique
+            $sql = 'select id from follows where id = ?';
+            $stmt = $dbh->prepare($sql);
+            if ($stmt === false) {
+                throw new \Federator\Exceptions\ServerError();
+            }
+            $stmt->bind_param("s", $idurl);
+            $foundId = 0;
+            $ret = $stmt->bind_result($foundId);
+            $stmt->execute();
+            if ($ret) {
+                $stmt->fetch();
+            }
+            $stmt->close();
+        } while ($foundId > 0);
+
+        // Add follow with created_at timestamp
+        $sql = 'insert into follows (id, source_user, target_user, created_at) values (?, ?, ?, NOW())';
+        $stmt = $dbh->prepare($sql);
+        if ($stmt === false) {
+            throw new \Federator\Exceptions\ServerError();
+        }
+        $stmt->bind_param("sss", $idurl, $sourceUser, $targetUserId);
+        $stmt->execute();
+        $stmt->close();
+        return $idurl; // Return the generated follow ID
+    }
+
+    /**
+     * remove follow
+     *
+     * @param \mysqli $dbh database handle
+     * @param string $sourceUser source user id
+     * @param string $targetUserId target user id
+     * @return bool true on success
+     */
+    public static function removeFollow($dbh, $sourceUser, $targetUserId)
+    {
+        $sql = 'delete from follows where source_user = ? and target_user = ?';
+        $stmt = $dbh->prepare($sql);
+        if ($stmt === false) {
+            throw new \Federator\Exceptions\ServerError();
+        }
+        $stmt->bind_param("ss", $sourceUser, $targetUserId);
+        $stmt->execute();
+        $affectedRows = $stmt->affected_rows;
+        $stmt->close();
+        return $affectedRows > 0;
+    }
 }

php/federator/dio/user.php

@@ -42,6 +42,7 @@ class User
                 throw new \Federator\Exceptions\ServerError();
             }
             $public = openssl_pkey_get_details($private_key)['key'];
+            $user->publicKey = $public;
             $private = '';
             openssl_pkey_export($private_key, $private);
             $sql = 'insert into users (id, externalid, rsapublic, rsaprivate, validuntil,';
@@ -100,13 +101,37 @@ class User
         }
     }
 
+    /**
+     * get private rsa key
+     * @return string|false key or false
+     */
+    public static function getrsaprivate(\mysqli $dbh, string $_user)
+    {
+        $sql = "select rsaprivate from users where id=?";
+        $stmt = $dbh->prepare($sql);
+        if ($stmt === false) {
+            throw new \Federator\Exceptions\ServerError();
+        }
+        $stmt->bind_param("s", $_user);
+        $ret = $stmt->bind_result($rsaPrivateKey);
+        $stmt->execute();
+        if ($ret) {
+            $stmt->fetch();
+        }
+        $stmt->close();
+        if ($rsaPrivateKey !== null) {
+            return $rsaPrivateKey;
+        }
+        return false;
+    }
+
     /**
      * extend the given user with internal data
      * @param \mysqli $dbh database  handle
      * @param \Federator\Data\User $user user to extend
      * @param string $_user user/profile name
      */
-    protected static function extendUser(\mysqli $dbh, $user, $_user) : void
+    protected static function extendUser(\mysqli $dbh, $user, $_user): void
     {
         $sql = 'select id,unix_timestamp(`validuntil`) from users where id=?';
         $stmt = $dbh->prepare($sql);

php/federator/main.php

@@ -280,6 +280,16 @@ class Main
         $this->host = $host;
     }
 
+    /**
+     * set content type
+     *
+     * @param string $_type content type
+     */
+    public function setContentType($_type): void
+    {
+        $this->contentType = $_type;
+    }
+
     /**
      * set response code
      *

plugins/federator/contentnation.php

@@ -54,11 +54,11 @@ class ContentNation implements Connector
      * get followers of given user
      *
      * @param string $userId user id
-     * @return \Federator\Data\ActivityPub\Common\APObject[]|false
+     * @return \Federator\Data\FedUser[]|false
      */
     public function getRemoteFollowersOfUser($userId)
     {
-        // todo implement queue for this, move to DIO
+        // todo implement queue for this
         if (preg_match("#^([^@]+)@([^/]+)#", $userId, $matches) == 1) {
             $userId = $matches[1];
         }
@@ -109,25 +109,25 @@ class ContentNation implements Connector
         $posts = [];
         if (array_key_exists('activities', $r)) {
             $activities = $r['activities'];
-            $host = $_SERVER['SERVER_NAME'];
+            $config = $this->main->getConfig();
+            $domain = $config['generic']['externaldomain'];
             $imgpath = $this->config['userdata']['path'];
             $userdata = $this->config['userdata']['url'];
             foreach ($activities as $activity) {
                 $create = new \Federator\Data\ActivityPub\Common\Create();
-                $create->setAActor('https://' . $host . '/' . $userId);
+                $create->setAActor('https://' . $domain . '/' . $userId);
                 $create->setID($activity['id'])
-                    ->setPublished($activity['timestamp'])
+                    ->setPublished($activity['published'] ?? $activity['timestamp'])
                     ->addTo("https://www.w3.org/ns/activitystreams#Public")
-                    ->addCC('https://' . $host . '/' . $userId . '/followers.json');
+                    ->addCC('https://' . $domain . '/' . $userId . '/followers');
+
                 switch ($activity['type']) {
                     case 'Article':
-                        $create->setURL('https://' . $host . '/' . $activity['language'] . '/' . $userId . '/'
+                        $create->setURL('https://' . $domain . '/' . $activity['name']);
-                            . $activity['name']);
                         $apArticle = new \Federator\Data\ActivityPub\Common\Article();
                         if (array_key_exists('tags', $activity)) {
                             foreach ($activity['tags'] as $tag) {
-                                $href = 'https://' . $host . '/' . $activity['language']
+                                $href = 'https://' . $domain . '/search.htm?tagsearch=' . urlencode($tag);
-                                    . '/search.htm?tagsearch=' . urlencode($tag);
                                 $tagObj = new \Federator\Data\ActivityPub\Common\Tag();
                                 $tagObj->setHref($href)
                                     ->setName('#' . urlencode(str_replace(' ', '', $tag)))
@@ -137,7 +137,7 @@ class ContentNation implements Connector
                         }
                         $apArticle->setPublished($activity['published'])
                             ->setName($activity['title'])
-                            ->setAttributedTo('https://' . $host . '/' . $activity['profilename'])
+                            ->setAttributedTo('https://' . $domain . '/' . $activity['profilename'])
                             ->setContent(
                                 $activity['teaser'] ??
                                 $this->main->translate(
@@ -147,11 +147,10 @@ class ContentNation implements Connector
                                 )
                             )
                             ->addTo("https://www.w3.org/ns/activitystreams#Public")
-                            ->addCC('https://' . $host . '/' . $userId . '/followers.json');
+                            ->addCC('https://' . $domain . '/' . $userId . '/followers.json');
                         $articleimage = $activity['imagealt'] ??
                             $this->main->translate($activity['language'], 'article', 'image');
-                        $idurl = 'https://' . $host . '/' . $activity['language']
+                        $idurl = 'https://' . $domain . '/' . $userId . '/' . $activity['name'];
-                            . '/' . $userId . '/' . $activity['name'];
                         $apArticle->setID($idurl)
                             ->setURL($idurl);
                         $image = $activity['image'] ?? $activity['profileimg'];
@@ -176,7 +175,7 @@ class ContentNation implements Connector
                         $posts[] = $create;
                         break; // Comment
                     case 'Vote':
-                        $url = 'https://' . $host . '/' . $activity['articlelang'] . $userId . '/'
+                        $url = 'https://' . $domain . '/' . $userId . '/'
                             . $activity['articlename'];
                         $url .= '/vote/' . $activity['id'];
                         $create->setURL($url);
@@ -204,8 +203,7 @@ class ContentNation implements Connector
                         $actor = new \Federator\Data\ActivityPub\Common\APObject('Person');
                         $actor->setName($activity['username']);
                         $like->setActor($actor);
-                        $url = 'https://' . $host . '/' . $activity['articlelang']
+                        $url = 'https://' . $domain . '/' . $userId . '/' . $activity['articlename'];
-                            . '/' . $userId . '/' . $activity['articlename'];
                         if ($activity['comment'] !== '') {
                             $url .= '/comment/' . $activity['comment'];
                         }

plugins/federator/dummyconnector.php

@@ -23,7 +23,7 @@ class DummyConnector implements Connector
      * get followers of given user
      *
      * @param string $userId user id @unused-param
-     * @return \Federator\Data\ActivityPub\Common\APObject[]|false
+     * @return \Federator\Data\FedUser[]|false
      */
     public function getRemoteFollowersOfUser($userId)
     {

plugins/federator/rediscache.php

@@ -90,7 +90,7 @@ class RedisCache implements Cache
      *
      * @param string $id user id @unused-param
 
-     * @return \Federator\Data\ActivityPub\Common\APObject[]|false
+     * @return \Federator\Data\FedUser[]|false
      */
     public function getRemoteFollowersOfUser($id)
     {
@@ -163,6 +163,26 @@ class RedisCache implements Cache
         return $user;
     }
 
+    /**
+     * get remote federation user by given name
+     *
+     * @param string $_name user/profile name
+     * @return \Federator\Data\FedUser | false
+     */
+    public function getRemoteFedUserByName(string $_name)
+    {
+        if (!$this->connected) {
+            $this->connect();
+        }
+        $key = self::createKey('u', $_name);
+        $data = $this->redis->get($key);
+        if ($data === false) {
+            return false;
+        }
+        $user = \Federator\Data\FedUser::createFromJson($data);
+        return $user;
+    }
+
     /**
      * get remote user by given session
      *
@@ -203,7 +223,7 @@ class RedisCache implements Cache
      * save remote followers by user
      *
      * @param string $user user name @unused-param
-     * @param \Federator\Data\ActivityPub\Common\APObject[]|false $followers user followers @unused-param
+     * @param \Federator\Data\FedUser[]|false $followers user followers @unused-param
      * @return void
      */
     public function saveRemoteFollowersOfUser($user, $followers)
@@ -252,6 +272,20 @@ class RedisCache implements Cache
         $this->redis->setEx($key, $this->userTTL, $serialized);
     }
 
+    /**
+     * save remote federation user by given name
+     *
+     * @param string $_name user/profile name
+     * @param \Federator\Data\FedUser $user user data
+     * @return void
+     */
+    public function saveRemoteFedUserByName(string $_name, \Federator\Data\FedUser $user)
+    {
+        $key = self::createKey('u', $_name);
+        $serialized = $user->toJson();
+        $this->redis->setEx($key, $this->userTTL, $serialized);
+    }
+
     /**
      * save remote user by given session
      *

sql/2025-05-06.sql

@@ -0,0 +1,3 @@
+create table follows(`id` varchar(255) unique primary key,`source_user` varchar(255) not null,`target_user` varchar(255) not null,`created_at` timestamp default current_timestamp,unique key `unique_follow` (`source_user`, `target_user`));
+create table fedusers(`id` varchar(255) unique primary key,`url` varchar(255) not null,`name` varchar(255) default '',`publickey` text default '',`summary` text default '',`validuntil` timestamp null default null,`type` enum('person', 'group') default 'person',`inboxurl` varchar(255) default null,`sharedinboxurl` varchar(255) default null,`followersurl` varchar(255) default null,`followingurl` varchar(255) default null,`publickeyid` varchar(255) default null,`outboxurl` varchar(255) default null,unique key `unique_feduser` (`url`),unique key `unique_feduser_id` (`url`));
+update settings set `value`="2025-05-06" where `key`="database_version";

templates/federator/user.json

@@ -58,7 +58,7 @@
             {rdelim}
         {rdelim}
     ],
-    "id":"https://{$fqdn}/users/{$username}",
+    "id":"https://{$fqdn}/{$username}",
     "type":"{$type}",
     "following":"https://{$fqdn}/users/{$username}/following",
     "followers":"https://{$fqdn}/users/{$username}/followers",
@@ -74,8 +74,8 @@
     "discoverable":true,
     "published":"{$registered}",
     "publicKey":{ldelim}
-    "id":"https://{$fqdn}/users/{$username}#main-key",
+    "id":"https://{$fqdn}/{$username}#main-key",
-    "owner":"https://{$fqdn}/users/{$username}",
+    "owner":"https://{$fqdn}/{$username}",
     "publicKeyPem":"{$publickey}"
     {rdelim},
     "tag":[],