bugfixes and refactoring, cleanup

.gitignore

@@ -5,3 +5,7 @@ php-docs
 .phpdoc
 phpdoc
 html
+/cache
+contentnation.ini
+*.pem*
+composer.phar

.phan/config.php

@@ -359,6 +359,7 @@ return [
     'directory_list' => [
         'vendor/phan/phan/src/Phan',
         'vendor/smarty/smarty/src',
+        'vendor/resque/php-resque/lib',
         'php/',
         'plugins',
         'htdocs',
@@ -367,5 +368,7 @@ return [
     // A list of individual files to include in analysis
     // with a path relative to the root directory of the
     // project.
-    'file_list' => [],
+    'file_list' => [
+        'phan-stubs.php',
+    ],
 ];

README.md

@@ -35,7 +35,7 @@ If the include redis cache is enabled,
 - install redis
 - create a users.acl for redis with the content:
 
-    user federator on ~u_* +get +set  ~s_* +get +setex ~m_* +get +setex >redis*change*password
+    user federator on ~u_* +get +set  ~s_* +get +setex ~m_* +get +setex ~publickey_* +get +setex >redis*change*password
 
 - change password in the rediscache.ini to match your given password.
 - install the redis plugin from pecl if not provided via your distro
@@ -52,9 +52,11 @@ To configure an apache server, add the following rewrite rules:
       RewriteCond expr "%{HTTP:content-type} -strcmatch '*application/activity+json*'"
       RewriteRule ^@(.*)$ /federator.php?_call=fedusers/$1 [L,END]
       RewriteRule ^users/(.*)$ /federator.php?_call=fedusers/$1 [L,END]
-      RewriteRule ^api/federator/(.+)$ federator.php?_call=$1 [L,END]
+      RewriteRule ^inbox[/]?$ /federator.php?_call=fedusers/inbox [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.

composer.json

@@ -3,7 +3,8 @@
     "description": "A federation service",
     "type": "project",
     "require": {
-        "smarty/smarty": "^5.3"
+        "smarty/smarty": "^5.3",
+        "resque/php-resque": "^1.3.6"
     },
     "license": "GPL-3.0-or-later",
     "authors": [
@@ -14,5 +15,10 @@
     ],
     "require-dev": {
         "phan/phan": "^5.4"
+    },
+    "autoload": {
+        "psr-4": {
+            "Federator\\": "php/federator/"
+        }
     }
 }

config.ini

@@ -1,5 +1,7 @@
 [generic]
-externaldomain = 'your.fqdn'
+protocol = 'https'
+externaldomain = 'federator.your.fqdn'
+sourcedomain = 'your.fqdn'
 
 [database]
 host = '127.0.0.1'
@@ -18,3 +20,7 @@ dummy = 'dummyconnector.php'
 [maintenance]
 username = 'federatoradmin'
 password = '*change*me*as*well'
+
+[keys]
+federatorPrivateKeyPath = 'federator.pem'
+federatorPublicKeyPath = 'federator.pem.pub'

formatsupport.json

@@ -0,0 +1,8 @@
+{
+    "activitypub": {
+        "article": [
+            "localhost",
+            "writefreely.org"
+        ]
+    }
+}

phan-stubs.php

@@ -0,0 +1,10 @@
+<?php
+
+if (!function_exists('getallheaders')) {
+    /**
+     * @return array<string, string>
+     */
+    function getallheaders(): array {
+        return [];
+    }
+}

php/federator/api.php

@@ -6,7 +6,7 @@
  * @author Sascha Nitsch (grumpydeveloper)
  **/
 
- namespace Federator;
+namespace Federator;
 
 /**
  * main API class
@@ -46,8 +46,8 @@ class Api extends Main
      */
     public function __construct()
     {
-        $this->contentType = "application/json";
-        Main::__construct();
+        $this->contentType = 'application/json';
+        parent::__construct();
     }
 
     /**
@@ -63,18 +63,18 @@ class Api extends Main
         while ($this->path[0] === '/') {
             $this->path = substr($this->path, 1);
         }
-        $this->paths = explode("/", $this->path);
+        $this->paths = explode('/', $this->path);
     }
 
     /**
      * main API function
      */
-    public function run() : void
+    public function run(): void
     {
-        $this->setPath((string)$_REQUEST['_call']);
+        $this->setPath((string) $_REQUEST['_call']);
         $this->openDatabase();
         $this->loadPlugins();
-        $retval = "";
+        $retval = '';
         $handler = null;
         if ($this->connector === null) {
             http_response_code(500);
@@ -100,12 +100,16 @@ class Api extends Main
                 break;
             case 'fedusers':
                 $handler = new Api\FedUsers($this);
+                $this->setContentType('application/activity+json');
                 break;
             case 'v1':
                 switch ($this->paths[1]) {
                     case 'dummy':
                         $handler = new Api\V1\Dummy($this);
                         break;
+                    case 'newcontent':
+                        $handler = new Api\V1\NewContent($this);
+                        break;
                 }
                 break;
         }
@@ -119,7 +123,7 @@ class Api extends Main
             } catch (Exceptions\Exception $e) {
                 $this->setResponseCode($e->getRetCode());
                 $retval = json_encode(array(
-                    "error" => $e->getMessage()
+                    'error' => $e->getMessage()
                 ));
             }
         } else {
@@ -135,26 +139,26 @@ class Api extends Main
         }
         if ($printresponse) {
             if ($this->redirect !== null) {
-                header("Location: $this->redirect");
+                header('Location: ' . $this->redirect);
             }
             if ($this->responseCode != 404) {
-                header("Content-type: " . $this->contentType);
-                header("Access-Control-Allow-Origin: *");
+                header('Content-type: ' . $this->contentType);
+                header('Access-Control-Allow-Origin: *');
             }
             if ($this->cacheTime == 0) {
-                header("Cache-Control: no-cache, no-store, must-revalidate");
-                header("Pragma: no-cache");
-                header("Expires: 0");
+                header('Cache-Control: no-cache, no-store, must-revalidate');
+                header('Pragma: no-cache');
+                header('Expires: 0');
             } else {
-                $ts = gmdate("D, d M Y H:i:s", time() + $this->cacheTime) . " GMT";
-                header("Expires: $ts");
-                header("Pragma: cache");
-                header("Cache-Control: max-age=" . $this->cacheTime);
+                $ts = gmdate('D, d M Y H:i:s', time() + $this->cacheTime) . ' GMT';
+                header('Expires: ' . $ts);
+                header('Pragma: cache');
+                header('Cache-Control: max-age=' . $this->cacheTime);
             }
             echo $retval;
         } else {
             if (!headers_sent()) {
-                header("Content-type: " . $this->contentType);
+                header('Content-type: ' . $this->contentType);
             }
         }
     }
@@ -168,7 +172,7 @@ class Api extends Main
      * @param string $message optional message
      * @throws Exceptions\PermissionDenied
      */
-    public function checkPermission($permission, $exception = "\Exceptions\PermissionDenied", $message = null) : void
+    public function checkPermission($permission, $exception = '\Exceptions\PermissionDenied', $message = null): void
     {
         // generic check first
         if ($this->user === false) {
@@ -191,6 +195,100 @@ class Api extends Main
         throw new $exception($message);
     }
 
+    /**
+     * check if the headers include a valid signature
+     *
+     * @param string[] $headers the headers
+     * @throws Exceptions\PermissionDenied
+     * @return string|Exceptions\PermissionDenied
+     */
+    public function checkSignature($headers)
+    {
+        if (isset($headers['X-Sender'])) {
+            try {
+                return $this->connector->checkSignature($headers);
+            } catch (Exceptions\PermissionDenied $e) {
+                http_response_code(500);
+                throw $e;
+            }
+        }
+
+        $signatureHeader = $headers['Signature'] ?? null;
+
+        if (!isset($signatureHeader)) {
+            throw new Exceptions\PermissionDenied('Missing Signature header');
+        }
+
+        // Parse Signature header
+        preg_match_all('/(\w+)=["\']?([^"\',]+)["\']?/', $signatureHeader, $matches);
+        $signatureParts = array_combine($matches[1], $matches[2]);
+
+        $signature = base64_decode($signatureParts['signature']);
+        $signedHeaders = explode(' ', $signatureParts['headers']);
+        $keyId = $signatureParts['keyId'];
+        $publicKeyPem = false;
+        if ($this->cache !== null) {
+            $publicKeyPem = $this->cache->getPublicKey($keyId);
+        }
+
+        if ($publicKeyPem === false) {
+            // Fetch public key from `keyId` (usually actor URL + #main-key)
+            [$publicKeyData, $info] = \Federator\Main::getFromRemote($keyId, ['Accept: application/activity+json']);
+
+            if ($info['http_code'] != 200) {
+                throw new Exceptions\PermissionDenied('Failed to fetch public key from keyId: ' . $keyId);
+            }
+
+            $actor = json_decode($publicKeyData, true);
+
+            if (!is_array($actor) || !isset($actor['id'])) {
+                throw new Exceptions\PermissionDenied('Invalid actor data');
+            }
+
+            $publicKeyPem = $actor['publicKey']['publicKeyPem'] ?? null;
+
+            if (!isset($publicKeyPem) || $publicKeyPem === false) {
+                http_response_code(500);
+                throw new Exceptions\PermissionDenied('Public key couldn\'t be determined');
+            }
+
+            // Cache the public key for 1 hour
+            if ($this->cache !== null) {
+                $this->cache->savePublicKey($keyId, $publicKeyPem);
+            }
+        }
+
+        // Reconstruct the signed string
+        $signedString = '';
+        foreach ($signedHeaders as $header) {
+            if ($header === '(request-target)') {
+                $method = strtolower($_SERVER['REQUEST_METHOD']);
+                $path = $_SERVER['REQUEST_URI'];
+                $headerValue = "$method $path";
+            } else {
+                $headerValue = $headers[ucwords($header, '-')] ?? '';
+            }
+
+            $signedString .= strtolower($header) . ': ' . $headerValue . "\n";
+        }
+
+        $signedString = rtrim($signedString);
+
+        // Verify the signature
+        $pubkeyRes = openssl_pkey_get_public($publicKeyPem);
+        $verified = false;
+        if ($pubkeyRes instanceof \OpenSSLAsymmetricKey && is_string($signature)) {
+            $verified = openssl_verify($signedString, $signature, $pubkeyRes, OPENSSL_ALGO_SHA256);
+        }
+        if ($verified != 1) {
+            http_response_code(500);
+            throw new Exceptions\PermissionDenied('Signature verification failed');
+        }
+
+        // Signature is valid!
+        return 'Signature verified.';
+    }
+
     /**
      * remove unwanted elements from html input
      *
@@ -198,7 +296,7 @@ class Api extends Main
      *          input to strip
      * @return string stripped input
      */
-    public static function stripHTML(string $_input) : string
+    public static function stripHTML(string $_input): string
     {
         $out = preg_replace('/<(script[^>]*)>/i', '&lt;${1}&gt;', $_input);
         $out = preg_replace('/<\/(script)>/i', '&lt;/${1};&gt;', $out);
@@ -212,7 +310,7 @@ class Api extends Main
      *          parameter to check
      * @return bool true if in
      */
-    public static function hasPost(string $_key) : bool
+    public static function hasPost(string $_key): bool
     {
         return array_key_exists($_key, $_POST);
     }
@@ -228,13 +326,13 @@ class Api extends Main
      */
     public function escapePost(string $key, $int = false)
     {
-        if (! array_key_exists($key, $_POST)) {
+        if (!array_key_exists($key, $_POST)) {
             return $int ? 0 : "";
         }
         if ($int === true) {
             return intval($_POST[$key]);
         }
-        $ret = $this->dbh->escape_string($this->stripHTML((string)$_POST[$key]));
+        $ret = $this->dbh->escape_string($this->stripHTML((string) $_POST[$key]));
         return $ret;
     }
 

php/federator/api/fedusers.php

@@ -16,7 +16,7 @@ class FedUsers implements APIInterface
     /**
      * main instance
      *
-     * @var \Federator\Main $main
+     * @var \Federator\Api $main
      */
     private $main;
 
@@ -47,26 +47,36 @@ class FedUsers implements APIInterface
      */
     public function exec($paths, $user)
     {
-        $method = $_SERVER["REQUEST_METHOD"];
+        $method = $_SERVER['REQUEST_METHOD'];
         $handler = null;
+        $_username = $paths[1];
         switch (sizeof($paths)) {
             case 2:
                 if ($method === 'GET') {
-                    // /users/username or /@username
-                    return $this->returnUserProfile($paths[1]);
+                    // /users/username or /@username or /username
+                    return $this->returnUserProfile($_username);
+                } else {
+                    switch ($paths[1]) {
+                        case 'inbox':
+                            $_username = null;
+                            $handler = new FedUsers\Inbox($this->main);
+                            break;
+                        default:
+                            break;
+                    }
                 }
                 break;
             case 3:
                 // /users/username/(inbox|outbox|following|followers)
                 switch ($paths[2]) {
                     case 'following':
-                        // $handler = new FedUsers\Following();
+                        $handler = new FedUsers\Following($this->main);
                         break;
                     case 'followers':
-                        // $handler = new FedUsers\Followers();
+                        $handler = new FedUsers\Followers($this->main);
                         break;
                     case 'inbox':
-                        // $handler = new FedUsers\Inbox();
+                        $handler = new FedUsers\Inbox($this->main);
                         break;
                     case 'outbox':
                         $handler = new FedUsers\Outbox($this->main);
@@ -82,10 +92,10 @@ class FedUsers implements APIInterface
             $ret = false;
             switch ($method) {
                 case 'GET':
-                    $ret = $handler->get($paths[1]);
+                    $ret = $handler->get($_username);
                     break;
                 case 'POST':
-                    $ret = $handler->post($paths[1]);
+                    $ret = $handler->post($_username);
                     break;
             }
             if ($ret !== false) {
@@ -115,22 +125,31 @@ class FedUsers implements APIInterface
         if ($user === false || $user->id === null) {
             throw new \Federator\Exceptions\FileNotFound();
         }
+        $config = $this->main->getConfig();
+        $domain = $config['generic']['externaldomain'];
+        $sourcedomain = $config['generic']['sourcedomain'];
+        $jsonKey = json_encode($user->publicKey);
+        if (!is_string($jsonKey)) {
+            throw new \Federator\Exceptions\FileNotFound();
+        }
         $data = [
             'iconMediaType' => $user->iconMediaType,
             'iconURL' => $user->iconURL,
             'imageMediaType' => $user->imageMediaType,
             'imageURL' => $user->imageURL,
-            'fqdn' => $_SERVER['SERVER_NAME'],
+            'fqdn' => $domain,
+            'sourcedomain' => $sourcedomain,
             'name' => $user->name,
             'username' => $user->id,
-            'publickey' => str_replace("\n", "\\n", $user->publicKey),
+            'publickey' => trim($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;
     }
+
     /**
      * set response
      *

php/federator/api/fedusers/followers.php

@@ -0,0 +1,123 @@
+<?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\Api\FedUsers;
+
+/**
+ * handle activitypub followers requests
+ */
+class Followers implements \Federator\Api\FedUsers\FedUsersInterface
+{
+    /**
+     * main instance
+     *
+     * @var \Federator\Api $main
+     */
+    private $main;
+
+    /**
+     * constructor
+     * @param \Federator\Api $main main instance
+     */
+    public function __construct($main)
+    {
+        $this->main = $main;
+    }
+
+    /**
+     * handle get call
+     *
+     * @param string|null $_user user to fetch followers for
+     * @return string|false response
+     */
+    public function get($_user)
+    {
+        if (!isset($_user)) {
+            return false;
+        }
+        $dbh = $this->main->getDatabase();
+        $cache = $this->main->getCache();
+        $connector = $this->main->getConnector();
+
+        // get user
+        $user = \Federator\DIO\User::getUserByName(
+            $dbh,
+            $_user,
+            $connector,
+            $cache
+        );
+        if ($user->id === null) {
+            return false;
+        }
+
+        $followers = new \Federator\Data\ActivityPub\Common\Followers();
+        $followerItems = \Federator\DIO\Followers::getFollowersByUser($dbh, $user->id, $connector, $cache);
+
+        $config = $this->main->getConfig();
+        $protocol = $config['generic']['protocol'];
+        $domain = $config['generic']['externaldomain'];
+        $baseUrl = $protocol . '://' . $domain . '/' . $_user . '/followers';
+
+        $pageSize = 10;
+        $page = $this->main->extractFromURI('page', '');
+        $id = $baseUrl;
+        $items = [];
+        $totalItems = count($followerItems);
+
+        if ($page !== '') {
+            $pageNum = max(0, (int) $page);
+            $offset = (int)($pageNum * $pageSize);
+            $pagedItems = array_slice($followerItems, $offset, $pageSize);
+
+            foreach ($pagedItems as $follower) {
+                $items[] = $follower->actorURL;
+            }
+            $followers->setItems($items);
+            $id .= '?page=' . urlencode($page);
+        }
+
+        $followers->setID($id);
+        $followers->setPartOf($baseUrl);
+        $followers->setTotalItems($totalItems);
+
+        // Pagination navigation
+        $lastPage = max(0, ceil($totalItems / $pageSize) - 1);
+
+        if ($page === '' || $followers->getCount() == 0) {
+            $followers->setFirst($baseUrl . '?page=0');
+            $followers->setLast($baseUrl . '?page=' . $lastPage);
+        }
+        if ($page !== '') {
+            $pageNum = max(0, (int) $page);
+            if ($pageNum < $lastPage) {
+                $followers->setNext($baseUrl . '?page=' . ($pageNum + 1));
+            }
+            if ($pageNum > 0) {
+                $followers->setPrev($baseUrl . '?page=' . ($pageNum - 1));
+            }
+            $followers->setFirst($baseUrl . '?page=0');
+            $followers->setLast($baseUrl . '?page=' . $lastPage);
+        } else {
+            $followers->setType('OrderedCollection');
+        }
+        $obj = $followers->toObject();
+
+        return json_encode($obj, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT);
+    }
+
+    /**
+     * handle post call
+     *
+     * @param string|null $_user user to add data to outbox @unused-param
+     * @return string|false response
+     */
+    public function post($_user)
+    {
+        return false;
+    }
+}

php/federator/api/fedusers/following.php

@@ -0,0 +1,122 @@
+<?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\Api\FedUsers;
+
+/**
+ * handle activitypub following requests
+ */
+class Following implements \Federator\Api\FedUsers\FedUsersInterface
+{
+    /**
+     * main instance
+     *
+     * @var \Federator\Api $main
+     */
+    private $main;
+
+    /**
+     * constructor
+     * @param \Federator\Api $main main instance
+     */
+    public function __construct($main)
+    {
+        $this->main = $main;
+    }
+
+    /**
+     * handle get call
+     *
+     * @param string|null $_user user to fetch followers for
+     * @return string|false response
+     */
+    public function get($_user)
+    {
+        if (!isset($_user)) {
+            return false;
+        }
+        $dbh = $this->main->getDatabase();
+        $cache = $this->main->getCache();
+        $connector = $this->main->getConnector();
+        // get user
+        $user = \Federator\DIO\User::getUserByName(
+            $dbh,
+            $_user,
+            $connector,
+            $cache
+        );
+        if ($user->id === null) {
+            return false;
+        }
+
+        $following = new \Federator\Data\ActivityPub\Common\Following();
+        $followingItems = \Federator\DIO\Followers::getFollowingByUser($dbh, $user->id, $connector, $cache);
+
+        $config = $this->main->getConfig();
+        $protocol = $config['generic']['protocol'];
+        $domain = $config['generic']['externaldomain'];
+        $baseUrl = $protocol . '://' . $domain . '/users/' . $_user . '/following';
+
+        $pageSize = 10;
+        $page = $this->main->extractFromURI('page', '');
+        $id = $baseUrl;
+        $items = [];
+        $totalItems = count($followingItems);
+
+        if ($page !== '') {
+            $pageNum = max(0, (int) $page);
+            $offset = (int) ($pageNum * $pageSize);
+            $pagedItems = array_slice($followingItems, $offset, $pageSize);
+
+            foreach ($pagedItems as $followed) {
+                $items[] = $followed->actorURL;
+            }
+            $following->setItems($items);
+            $id .= '?page=' . urlencode($page);
+        }
+
+        $following->setID($id);
+        $following->setPartOf($baseUrl);
+        $following->setTotalItems($totalItems);
+
+        // Pagination navigation
+        $lastPage = max(0, ceil($totalItems / $pageSize) - 1);
+
+        if ($page === '' || $following->getCount() == 0) {
+            $following->setFirst($baseUrl . '?page=0');
+            $following->setLast($baseUrl . '?page=' . $lastPage);
+        }
+        if ($page !== '') {
+            $pageNum = max(0, (int) $page);
+            if ($pageNum < $lastPage) {
+                $following->setNext($baseUrl . '?page=' . ($pageNum + 1));
+            }
+            if ($pageNum > 0) {
+                $following->setPrev($baseUrl . '?page=' . ($pageNum - 1));
+            }
+            $following->setFirst($baseUrl . '?page=0');
+            $following->setLast($baseUrl . '?page=' . $lastPage);
+        } else {
+            $following->setType('OrderedCollection');
+        }
+        $obj = $following->toObject();
+
+        return json_encode($obj, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT);
+    }
+
+    /**
+     * handle post call
+     *
+     * @param string|null $_user user to add data to outbox @unused-param
+     * @return string|false response
+     */
+    public function post($_user)
+    {
+        return false;
+    }
+}

php/federator/api/fedusers/inbox.php

@@ -0,0 +1,262 @@
+<?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\Api\FedUsers;
+
+/**
+ * handle activitypub inbox requests
+ */
+class Inbox implements \Federator\Api\FedUsers\FedUsersInterface
+{
+    /**
+     * main instance
+     *
+     * @var \Federator\Api $main
+     */
+    private $main;
+
+    /**
+     * constructor
+     * @param \Federator\Api $main api main instance
+     */
+    public function __construct($main)
+    {
+        $this->main = $main;
+    }
+
+    /**
+     * handle get call
+     *
+     * @param string|null $_user user to fetch inbox for @unused-param
+     * @return string|false response
+     */
+    public function get($_user)
+    {
+        return false;
+    }
+
+    /**
+     * handle post call
+     *
+     * @param string|null $_user user to add data to inbox
+     * @return string|false response
+     */
+    public function post($_user)
+    {
+        $_rawInput = file_get_contents('php://input');
+
+        $allHeaders = getallheaders();
+        try {
+            $this->main->checkSignature($allHeaders);
+        } catch (\Federator\Exceptions\PermissionDenied $e) {
+            error_log("signature check failed");
+            throw new \Federator\Exceptions\Unauthorized('Inbox::post Signature check failed: ' . $e->getMessage());
+        }
+
+        $activity = is_string($_rawInput) ? json_decode($_rawInput, true) : null;
+
+        $dbh = $this->main->getDatabase();
+        $cache = $this->main->getCache();
+        $connector = $this->main->getConnector();
+
+        $config = $this->main->getConfig();
+        if (!is_array($activity)) {
+            throw new \Federator\Exceptions\ServerError('Inbox::post Input wasn\'t of type array');
+        }
+
+        $inboxActivity = \Federator\Data\ActivityPub\Factory::newActivityFromJson($activity);
+
+        if ($inboxActivity === false) {
+            throw new \Federator\Exceptions\ServerError('Inbox::post couldn\'t create inboxActivity');
+        }
+        $actor = $inboxActivity->getAActor(); // url of the sender https://contentnation.net/username
+        $username = basename((string) (parse_url($actor, PHP_URL_PATH) ?? ''));
+        $domain = parse_url($actor, PHP_URL_HOST);
+        $userId = $username . '@' . $domain;
+        $user = \Federator\DIO\FedUser::getUserByName(
+            $dbh,
+            $userId,
+            $cache
+        );
+        if ($user === null || $user->id === null) {
+            error_log('Inbox::post couldn\'t find user: ' . $userId);
+            throw new \Federator\Exceptions\ServerError('Inbox::post couldn\'t find user: ' . $userId);
+        }
+
+        $users = [];
+
+        $receivers = array_merge($inboxActivity->getTo(), $inboxActivity->getCC());
+
+        // For Undo, the object may hold the proper to/cc
+        if ($inboxActivity->getType() === 'Undo') {
+            $object = $inboxActivity->getObject();
+            if ($object !== null && is_object($object)) {
+                $receivers = array_merge($object->getTo(), $object->getCC());
+            }
+        }
+
+        // Filter out the public address and keep only actual URLs
+        $receivers = array_filter($receivers, static function (mixed $receiver): bool {
+            return is_string($receiver)
+                && $receiver !== 'https://www.w3.org/ns/activitystreams#Public'
+                && (filter_var($receiver, FILTER_VALIDATE_URL) !== false);
+        });
+
+        if (isset($_user)) {
+            $receivers[] = $dbh->real_escape_string($_user); // Add the target user to the receivers list
+        }
+
+        // Special handling for Follow and Undo follow activities
+        if (strtolower($inboxActivity->getType()) === 'follow') {
+            // For Follow, the object should hold the target
+            $object = $inboxActivity->getObject();
+            if ($object !== null && is_string($object)) {
+                $receivers[] = $object;
+            }
+        } elseif (strtolower($inboxActivity->getType()) === 'undo') {
+            $object = $inboxActivity->getObject();
+            if ($object !== null && is_object($object)) {
+                // For Undo, the objects object should hold the target
+                if (strtolower($object->getType()) === 'follow') {
+                    $objObject = $object->getObject();
+                    if ($objObject !== null && is_string($objObject)) {
+                        $receivers[] = $objObject;
+                    }
+                }
+            }
+        }
+        $ourDomain = $config['generic']['externaldomain'];
+
+        $finalReceivers = [];
+        foreach ($receivers as $receiver) {
+            if ($receiver === '' || !is_string($receiver)) {
+                continue;
+            }
+            if (!str_contains($receiver, $ourDomain) && $receiver !== $_user) {
+                continue;
+            }
+            // check if receiver is an actor url from our domain
+            if ($receiver !== $_user) {
+                $receiverName = basename((string) (parse_url($receiver, PHP_URL_PATH) ?? ''));
+                $ourDomain = parse_url($receiver, PHP_URL_HOST);
+                if ($receiverName === null || $ourDomain === null) {
+                    error_log('Inbox::post no receiverName or domain found for receiver: ' . $receiver);
+                    continue;
+                }
+                if ($receiverName[0] === '@') {
+                    $receiverName = substr($receiverName, 1);
+                }
+                $receiver = $receiverName;
+            }
+            $finalReceivers[] = $receiver;
+        }
+        $finalReceivers = array_unique($finalReceivers); // remove duplicates
+        foreach ($finalReceivers as $receiver) {
+            if (str_ends_with($receiver, '/followers')) {
+                $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);
+                error_log("url $actor to username $username domain $domain");
+                if ($username === null || $domain === null) {
+                    error_log('Inbox::post no username or domain found for recipient: ' . $receiver);
+                    continue;
+                }
+                try {
+                    $followers = \Federator\DIO\Followers::getFollowersByFedUser(
+                        $dbh,
+                        $connector,
+                        $cache,
+                        $username . '@' . $domain
+                    );
+                } catch (\Throwable $e) {
+                    error_log('Inbox::post get followers for user: ' . $username . '@' . $domain . '. Exception: '
+                      . $e->getMessage());
+                    continue;
+                }
+
+                if (is_array($followers)) {
+                    $users = array_merge($users, array_column($followers, 'id'));
+                }
+            } else {
+                try {
+                    $localUser = \Federator\DIO\User::getUserByName(
+                        $dbh,
+                        $receiver,
+                        $connector,
+                        $cache
+                    );
+                } catch (\Throwable $e) {
+                    error_log('Inbox::post get user by name: ' . $receiver . '. Exception: ' . $e->getMessage());
+                    continue;
+                }
+                if ($localUser === null || $localUser->id === null) {
+                    error_log('Inbox::post 210 couldn\'t find user: ' . $receiver);
+                    continue;
+                }
+                $users[] = $localUser->id;
+            }
+        }
+
+        $users = array_unique($users); // remove duplicates
+
+        if (empty($users)) { // todo remove after proper implementation, debugging for now
+            $rootDir = '/tmp/';
+            // Save the raw input and parsed JSON to a file for inspection
+            file_put_contents(
+                $rootDir . 'logs/inbox.log',
+                date('Y-m-d H:i:s') . ": ==== POST Inbox Activity ====\n"
+                    . json_encode($inboxActivity, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT) . "\n\n",
+                FILE_APPEND
+            );
+        }
+
+        // Set the Redis backend for Resque
+        $rconfig = parse_ini_file($_SERVER['DOCUMENT_ROOT'] . '/../rediscache.ini');
+        $redisUrl = sprintf(
+            'redis://%s:%s@%s:%d?password-encoding=u',
+            urlencode($rconfig['username']),
+            urlencode($rconfig['password']),
+            $rconfig['host'],
+            intval($rconfig['port'], 10)
+        );
+        \Resque::setBackend($redisUrl);
+
+        foreach ($users as $receiver) {
+            if (!isset($receiver)) {
+                continue;
+            }
+            $token = \Resque::enqueue('inbox', 'Federator\\Jobs\\InboxJob', [
+                'user' => $user->id,
+                'recipientId' => $receiver,
+                'activity' => $inboxActivity->toObject(),
+            ]);
+            error_log('Inbox::post enqueued job for user: ' . $user->id . ' with token: ' . $token);
+        }
+        if (empty($users)) {
+            $type = strtolower($inboxActivity->getType());
+            if ($type === 'undo' || $type === 'delete') {
+                $token = \Resque::enqueue('inbox', 'Federator\\Jobs\\InboxJob', [
+                    'user' => $user->id,
+                    'recipientId' => "",
+                    'activity' => $inboxActivity->toObject(),
+                ]);
+                error_log('Inbox::post enqueued job for user: ' . $user->id . ' with token: ' . $token);
+            } else {
+                error_log('Inbox::post no users found for activity, doing nothing: '
+                    . json_encode($inboxActivity, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT));
+            }
+        }
+        return 'success';
+    }
+}

php/federator/api/fedusers/outbox.php

@@ -16,13 +16,13 @@ class Outbox implements \Federator\Api\FedUsers\FedUsersInterface
     /**
      * main instance
      *
-     * @var \Federator\Main $main
+     * @var \Federator\Api $main
      */
     private $main;
 
     /**
      * constructor
-     * @param \Federator\Main $main main instance
+     * @param \Federator\Api $main main instance
      */
     public function __construct($main)
     {
@@ -32,11 +32,14 @@ class Outbox implements \Federator\Api\FedUsers\FedUsersInterface
     /**
      * handle get call
      *
-     * @param string $_user user to fetch outbox for
+     * @param string|null $_user user to fetch outbox for
      * @return string|false response
      */
     public function get($_user)
     {
+        if (!isset($_user)) {
+            return false;
+        }
         $dbh = $this->main->getDatabase();
         $cache = $this->main->getCache();
         $connector = $this->main->getConnector();
@@ -50,42 +53,46 @@ class Outbox implements \Federator\Api\FedUsers\FedUsersInterface
         if ($user->id === null) {
             return false;
         }
+
         // get posts from user
         $outbox = new \Federator\Data\ActivityPub\Common\Outbox();
-        $min = $this->main->extractFromURI("min", "");
-        $max = $this->main->extractFromURI("max", "");
-        $page = $this->main->extractFromURI("page", "");
+        $min = intval($this->main->extractFromURI('min', '0'), 10);
+        $max = intval($this->main->extractFromURI('max', '0'), 10);
+        $page = $this->main->extractFromURI('page', '');
         if ($page !== "") {
-            $items = \Federator\DIO\Posts::getPostsByUser($dbh, $user->id, $connector, $cache, $min, $max);
+            $items = \Federator\DIO\Posts::getPostsByUser($dbh, $user->id, $connector, $cache, $min, $max, 20);
             $outbox->setItems($items);
         } else {
+            $tmpitems = \Federator\DIO\Posts::getPostsByUser($dbh, $user->id, $connector, $cache, $min, $max, 99999);
+            $outbox->setTotalItems(sizeof($tmpitems));
             $items = [];
         }
-        $host = $_SERVER['SERVER_NAME'];
-        $id = 'https://' . $host .'/' . $_user . '/outbox';
+        $config = $this->main->getConfig();
+        $protocol = $config['generic']['protocol'];
+        $domain = $config['generic']['externaldomain'];
+        $id = $protocol . '://' . $domain . '/' . $_user . '/outbox';
         $outbox->setPartOf($id);
         $outbox->setID($id);
-        if ($page !== '') {
-            $id .= '?page=' . urlencode($page);
+        if ($page === '') {
+            $outbox->setType('OrderedCollection');
         }
-        if ($page === '' || $outbox->count() == 0) {
-            $outbox->setFirst($id);
-            $outbox->setLast($id . '&min=0');
+        if ($page === '' || $outbox->getCount() == 0) {
+            $outbox->setFirst($id . '?page=true');
         }
-        if (sizeof($items)>0) {
-            $newestId = $items[0]->getPublished();
-            $oldestId = $items[sizeof($items)-1]->getPublished();
-            $outbox->setNext($id . '&max=' . $newestId);
-            $outbox->setPrev($id . '&min=' . $oldestId);
+        if (sizeof($items) > 0) {
+            $oldestTS = $items[0]->getPublished();
+            $newestTS = $items[sizeof($items) - 1]->getPublished();
+            $outbox->setNext($id . '?page=true&max=' . $newestTS);
+            $outbox->setPrev($id . '?page=true&min=' . $oldestTS);
         }
         $obj = $outbox->toObject();
-        return json_encode($obj);
+        return json_encode($obj, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT);
     }
 
     /**
      * handle post call
      *
-     * @param string $_user user to add data to outbox @unused-param
+     * @param string|null $_user user to add data to outbox @unused-param
      * @return string|false response
      */
     public function post($_user)

php/federator/api/v1/dummy.php

@@ -41,10 +41,10 @@ class Dummy implements \Federator\Api\APIInterface
      * run given url path
      *
      * @param array<string> $paths path array split by /
-     * @param \Federator\Data\User|false $user user who is calling us
+     * @param \Federator\Data\User|false $user user who is calling us @unused-param
      * @return bool true on success
      */
-    public function exec($paths, $user) : bool
+    public function exec($paths, $user): bool
     {
         // only for user with the 'publish' permission
         if ($user === false || $user->hasPermission('publish') === false) {
@@ -58,6 +58,7 @@ class Dummy implements \Federator\Api\APIInterface
                         if ($paths[2] === 'moo') {
                             return $this->getDummy();
                         }
+                        break;
                 }
                 break;
             case 'POST':
@@ -68,6 +69,7 @@ class Dummy implements \Federator\Api\APIInterface
                         }
                         break;
                 }
+                break;
         }
         $this->main->setResponseCode(404);
         return false;

php/federator/api/v1/newcontent.php

@@ -0,0 +1,480 @@
+<?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\Api\V1;
+
+/**
+ * Called from our application to inform us about new content (f.e. new posts on contentnation.net)
+ */
+class NewContent implements \Federator\Api\APIInterface
+{
+    /**
+     * main instance
+     *
+     * @var \Federator\Api $main
+     */
+    private $main;
+
+    /**
+     * response from sub-calls
+     *
+     * @var string $response
+     */
+    private $response;
+
+    /**
+     * constructor
+     *
+     * @param \Federator\Main $main main instance
+     * @return void
+     */
+    public function __construct($main)
+    {
+        $this->main = $main;
+    }
+
+    /**
+     * run given url path
+     *
+     * @param array<string> $paths path array split by /
+     * @param \Federator\Data\User|false $user user who is calling us @unused-param
+     * @return bool true on success
+     */
+    public function exec($paths, $user)
+    {
+        $method = $_SERVER['REQUEST_METHOD'];
+        $_username = $paths[2];
+        if ($method === 'GET') { // unsupported
+            /// TODO: throw unsupported method exception
+            throw new \Federator\Exceptions\InvalidArgument('GET not supported');
+        }
+        switch (sizeof($paths)) {
+            case 3:
+                $ret = $this->post($_username);
+                break;
+        }
+
+        if (isset($ret) && $ret !== false) {
+            $this->response = $ret;
+            return true;
+        }
+
+        $this->main->setResponseCode(404);
+        return false;
+    }
+
+    /**
+     * handle post call
+     *
+     * @param string|null $_user optional user that triggered the post
+     * @return string|false response
+     */
+    public function post($_user)
+    {
+        $_rawInput = file_get_contents('php://input');
+        $allHeaders = getallheaders();
+        try {
+            $this->main->checkSignature($allHeaders);
+        } catch (\Federator\Exceptions\PermissionDenied $e) {
+            error_log('NewContent::post Signature check failed: ' . $e->getMessage());
+            http_response_code(401);
+            return false;
+        }
+
+        $input = is_string($_rawInput) ? json_decode($_rawInput, true) : null;
+
+
+        $dbh = $this->main->getDatabase();
+        $cache = $this->main->getCache();
+        $connector = $this->main->getConnector();
+
+        $config = $this->main->getConfig();
+        $domain = $config['generic']['externaldomain'];
+        if (!is_array($input)) {
+            error_log('NewContent::post Input wasn\'t of type array');
+            return false;
+        }
+
+        $articleId = '';
+        if (isset($allHeaders['X-Sender'])) {
+            $newActivity = $connector->jsonToActivity($input, $articleId);
+        } else {
+            error_log('NewContent::post No X-Sender header found');
+            return false;
+        }
+        if ($newActivity === false) {
+            error_log('NewContent::post couldn\'t create newActivity');
+            return false;
+        }
+        if (!isset($_user)) {
+            $user = $newActivity->getAActor(); // url of the sender https://contentnation.net/username
+            $posterName = str_replace(
+                $domain,
+                '',
+                $user
+            ); // retrieve only the last part of the url
+        } else {
+            $posterName = $dbh->real_escape_string($_user);
+        }
+
+        $users = [];
+
+        $receivers = array_merge($newActivity->getTo(), $newActivity->getCC());
+
+        // For Undo, the object may hold the proper to/cc
+        if ($newActivity->getType() === 'Undo') {
+            $object = $newActivity->getObject();
+            if ($object !== null && is_object($object)) {
+                $receivers = array_merge($object->getTo(), $object->getCC());
+            }
+        }
+
+        // Filter out the public address and keep only actual URLs
+        $receivers = array_filter($receivers, static function (mixed $receiver): bool {
+            return is_string($receiver)
+                && $receiver !== 'https://www.w3.org/ns/activitystreams#Public'
+                && (filter_var($receiver, FILTER_VALIDATE_URL) !== false);
+        });
+
+        foreach ($receivers as $receiver) {
+            if ($receiver === '' || !is_string($receiver)) {
+                continue;
+            }
+
+            if (str_ends_with($receiver, '/followers')) {
+                if ($posterName === null) {
+                    error_log('NewContent::post no username found');
+                    continue;
+                }
+                try {
+                    $followers = \Federator\DIO\Followers::getFollowersByUser($dbh, $posterName, $connector, $cache);
+                } catch (\Throwable $e) {
+                    error_log('NewContent::post get followers for user: ' . $posterName . '. Exception: '
+                        . $e->getMessage());
+                    continue;
+                }
+
+                if (is_array($followers)) {
+                    $users = array_merge($users, array_column($followers, 'id'));
+                }
+            } else {
+                // check if receiver is an actor url and not from our domain
+                if (str_contains($receiver, $domain)) {
+                    continue;
+                }
+                $receiverName = basename((string) (parse_url($receiver, PHP_URL_PATH) ?? ''));
+                $domain = parse_url($receiver, PHP_URL_HOST);
+                if ($receiverName === null || $domain === null) {
+                    if ($receiver === $posterName) {
+                        continue;
+                    }
+                    error_log('NewContent::post no receiverName or domain found for receiver: ' . $receiver);
+                    continue;
+                }
+                $receiver = $receiverName . '@' . $domain;
+                try {
+                    $user = \Federator\DIO\FedUser::getUserByName(
+                        $dbh,
+                        $receiver,
+                        $cache
+                    );
+                } catch (\Throwable $e) {
+                    error_log('NewContent::post get user by name: ' . $receiver . '. Exception: ' . $e->getMessage());
+                    continue;
+                }
+                if ($user === null || $user->id === null) {
+                    error_log('NewContent::post couldn\'t find user: ' . $receiver);
+                    continue;
+                }
+                $users[] = $user->id;
+            }
+        }
+
+        $users = array_unique($users); // remove duplicates
+
+        if (empty($users)) { // todo remove after proper implementation, debugging for now
+            $rootDir = PROJECT_ROOT . '/';
+            // Save the raw input and parsed JSON to a file for inspection
+            file_put_contents(
+                $rootDir . 'logs/newContent.log',
+                date('Y-m-d H:i:s') . ": ==== POST NewContent Activity ====\n"
+                    . json_encode($newActivity, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT) . "\n\n",
+                FILE_APPEND
+            );
+        }
+
+        foreach ($users as $receiver) {
+            if (!isset($receiver)) {
+                continue;
+            }
+
+            $token = \Resque::enqueue('inbox', 'Federator\\Jobs\\NewContentJob', [
+                'user' => $posterName,
+                'recipientId' => $receiver,
+                'activity' => $newActivity->toObject(),
+                'articleId' => $articleId,
+            ]);
+            error_log('Inbox::post enqueued job for receiver: ' . $receiver . ' with token: ' . $token);
+        }
+
+        return json_encode($newActivity, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT);
+    }
+
+    /**
+     * 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 $host host url of our server (e.g. https://federator.com)
+     * @param string $_user user that triggered the post
+     * @param string $_recipientId recipient of the post
+     * @param \Federator\Data\ActivityPub\Common\Activity $newActivity the activity that we received
+     * @param string $articleId the original id of the article (if applicable)
+     *                           (used to identify the article in the remote system)
+     * @return boolean response
+     */
+    public static function postForUser($dbh, $connector, $cache, $host, $_user, $_recipientId, $newActivity, $articleId)
+    {
+        if (!isset($_user)) {
+            error_log('NewContent::postForUser no user given');
+            return false;
+        }
+
+        // get sender
+        $user = \Federator\DIO\User::getUserByName(
+            $dbh,
+            $_user,
+            $connector,
+            $cache
+        );
+        if ($user === null || $user->id === null) {
+            error_log('NewContent::postForUser couldn\'t find user: ' . $_user);
+            return false;
+        }
+
+        // get recipient
+        $recipient = \Federator\DIO\FedUser::getUserByName(
+            $dbh,
+            $_recipientId,
+            $cache
+        );
+        if ($recipient === null || $recipient->id === null) {
+            error_log('NewContent::postForUser couldn\'t find user: ' . $_recipientId);
+            return false;
+        }
+
+        $rootDir = PROJECT_ROOT . '/';
+        // Save the raw input and parsed JSON to a file for inspection
+        file_put_contents(
+            $rootDir . 'logs/newcontent_' . $recipient->id . '.log',
+            date('Y-m-d H:i:s') . ": ==== POST " . $recipient->id . " NewContent Activity ====\n"
+                . json_encode($newActivity, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT) . "\n\n",
+            FILE_APPEND
+        );
+
+        $type = strtolower($newActivity->getType());
+
+        switch ($type) {
+            case 'follow':
+                // $success = false;
+                $actor = $newActivity->getAActor();
+                if ($actor !== '') {
+                    $newIdUrl = \Federator\DIO\Followers::generateNewFollowId($dbh, $host);
+                    $newActivity->setID($newIdUrl);
+                    /*if (is_string($followerDomain)) {
+                        $followerId = "{$followerUsername}@{$followerDomain}";
+                        $success = \Federator\DIO\Followers::sendFollowRequest($dbh, $connector, $cache, $user->id,
+                          $followerId, $followerDomain);
+                    }*/
+                }
+                /* if ($success === false) {
+                    error_log("NewContent::postForUser Failed to add follower for user $user->id");
+                } */
+                break;
+
+            case 'delete':
+                // Delete Note/Post
+                $object = $newActivity->getObject();
+                if (is_string($object)) {
+                    \Federator\DIO\Posts::deletePost($dbh, $object);
+                } elseif (is_object($object)) {
+                    $objectId = $object->getID();
+                    \Federator\DIO\Posts::deletePost($dbh, $objectId);
+                }
+                break;
+
+            case 'undo':
+                $object = $newActivity->getObject();
+                if (is_object($object)) {
+                    switch (strtolower($object->getType())) {
+                        case 'follow':
+                            $success = false;
+                            if ($object instanceof \Federator\Data\ActivityPub\Common\Activity) {
+                                $actor = $object->getAActor();
+                                if ($actor !== '') {
+                                    $followerUsername = basename((string) (parse_url($actor, PHP_URL_PATH) ?? ''));
+                                    $followerDomain = parse_url($actor, PHP_URL_HOST);
+                                    if (is_string($followerDomain)) {
+                                        $followerId = $followerUsername . '@' . $followerDomain;
+                                        $removedId = \Federator\DIO\Followers::removeFollow(
+                                            $dbh,
+                                            $followerId,
+                                            $user->id
+                                        );
+                                        if ($removedId !== false) {
+                                            $object->setID($removedId);
+                                            $newActivity->setObject($object);
+                                            $success = true;
+                                        } else {
+                                            error_log('NewContent::postForUser Failed to remove follow for user '
+                                                . $user->id);
+                                        }
+                                    }
+                                }
+                            }
+                            if ($success === false) {
+                                error_log('NewContent::postForUser Failed to remove follower for user ' . $user->id);
+                            }
+                            break;
+                        case 'like':
+                        case 'dislike':
+                            if (method_exists($object, 'getObject')) {
+                                $targetId = $object->getObject();
+                                if (is_string($targetId)) {
+                                    \Federator\DIO\Votes::removeVote($dbh, $user->id, $targetId);
+                                } else {
+                                    error_log('NewContent::postForUser Error in Undo Like/Dislike for user ' . $user->id
+                                      . ', targetId is not a string');
+                                }
+                            }
+                            break;
+                        case 'note':
+                            // Undo Note (remove note)
+                            $noteId = $object->getID();
+                            \Federator\DIO\Posts::deletePost($dbh, $noteId);
+                            break;
+                        case 'article':
+                            $articleId = $object->getID();
+                            \Federator\DIO\Posts::deletePost($dbh, $articleId);
+                            // also remove latest saved article-update
+                            \Federator\DIO\Posts::deletePost($dbh, $articleId . '#update');
+
+                            // Undo Article (remove article)
+                            $idPart = strrchr($recipient->id, '@');
+                            if ($idPart === false) {
+                                error_log('NewContent::postForUser Error in Undo Article. ' . $recipient->id
+                                    . ', recipient ID is not valid');
+                                return false;
+                            } else {
+                                $targetUrl = ltrim($idPart, '@');
+
+                                if ($object instanceof \Federator\Data\ActivityPub\Common\Article) {
+                                    $object = \Federator\DIO\Article::conditionalConvertToNote($object, $targetUrl);
+                                    $newActivity->setObject($object);
+                                } else {
+                                    error_log('NewContent::postForUser Error in Undo Article for recipient '
+                                        . $recipient->id . ', object is not an Article');
+                                }
+                            }
+
+                            break;
+                    }
+                } elseif (is_string($object)) {
+                    \Federator\DIO\Posts::deletePost($dbh, $object);
+                } else {
+                    error_log('NewContent::postForUser Error in Undo for recipient ' . $recipient->id
+                        . ', object is not a string or object');
+                }
+                break;
+
+            case 'like':
+            case 'dislike':
+                // Add Like/Dislike
+                $targetId = $newActivity->getObject();
+                if (is_string($targetId)) {
+                    \Federator\DIO\Votes::addVote($dbh, $user->id, $targetId, $type);
+                    // \Federator\DIO\Posts::savePost($dbh, $user->id, $newActivity, $articleId);
+                } else {
+                    error_log('NewContent::postForUser Error in Add Like/Dislike for recipient ' . $recipient->id
+                        . ', targetId is not a string');
+                    return false;
+                }
+                break;
+
+            case 'create':
+            case 'update':
+                $object = $newActivity->getObject();
+                if (is_object($object)) {
+                    switch (strtolower($object->getType())) {
+                        case 'note':
+                            \Federator\DIO\Posts::savePost($dbh, $user->id, $newActivity, $articleId);
+
+                            break;
+                        case 'article':
+                            \Federator\DIO\Posts::savePost($dbh, $user->id, $newActivity, $articleId);
+
+                            $idPart = strrchr($recipient->id, '@');
+                            if ($idPart === false) {
+                                error_log('NewContent::postForUser Error in Create/Update Article. ' . $recipient->id
+                                    . ', recipient ID is not valid');
+                                return false;
+                            } else {
+                                $targetUrl = ltrim($idPart, '@');
+
+                                if ($object instanceof \Federator\Data\ActivityPub\Common\Article) {
+                                    $object = \Federator\DIO\Article::conditionalConvertToNote($object, $targetUrl);
+                                    $newActivity->setObject($object);
+                                } else {
+                                    error_log('NewContent::postForUser Error in Create/Update Article for recipient '
+                                        . $recipient->id . ', object is not an Article');
+                                }
+                            }
+
+                            break;
+                        default:
+                            \Federator\DIO\Posts::savePost($dbh, $user->id, $newActivity, $articleId);
+                            break;
+                    }
+                }
+                // Post Note
+                break;
+
+            default:
+                error_log('NewContent::postForUser Unhandled activity type $type for user ' . $user->id);
+                break;
+        }
+
+        try {
+            $response = \Federator\DIO\Server::sendActivity($dbh, $host, $user, $recipient, $newActivity);
+        } catch (\Exception $e) {
+            error_log('NewContent::postForUser Failed to send activity: ' . $e->getMessage());
+            return false;
+        }
+        if (empty($response)) {
+            error_log('NewContent::postForUser Sent activity to ' . $recipient->id);
+        } else {
+            error_log('NewContent::postForUser Sent activity to ' . $recipient->id . ' with response: '
+                . json_encode($response, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT));
+        }
+
+        return true;
+    }
+
+    /**
+     * get internal represenation as json string
+     * @return string json string or html
+     */
+    public function toJson()
+    {
+        return $this->response;
+    }
+}

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', $data);
         return true;
@@ -59,7 +61,7 @@ class WellKnown implements APIInterface
      */
     public function exec($paths, $user)
     {
-        $method = $_SERVER["REQUEST_METHOD"];
+        $method = $_SERVER['REQUEST_METHOD'];
         switch ($method) {
             case 'GET':
                 switch (sizeof($paths)) {

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') {
@@ -65,7 +67,6 @@ class NodeInfo
                     $template = 'nodeinfo2.0.json';
             }
             $stats = \Federator\DIO\Stats::getStats($this->main);
-            echo "fetch usercount via connector\n";
             $data['usercount'] = $stats->userCount;
             $data['postcount'] = $stats->postCount;
             $data['commentcount'] = $stats->commentCount;

php/federator/api/wellknown/webfinger.php

@@ -48,7 +48,8 @@ class WebFinger
         $matches = [];
         $config = $this->main->getConfig();
         $domain = $config['generic']['externaldomain'];
-        if (preg_match("/^acct:([^@]+)@(.*)$/", $_resource, $matches) != 1 || $matches[2] !== $domain) {
+        $sourcedomain = $config['generic']['sourcedomain'];
+        if (preg_match("/^acct:([^@]+)@(.*)$/", $_resource, $matches) != 1 || ($matches[2] !== $sourcedomain && $matches[2] !== $domain)) {
             throw new \Federator\Exceptions\InvalidArgument();
         }
         $user = \Federator\DIO\User::getUserByName(
@@ -63,6 +64,7 @@ class WebFinger
         $data = [
             'username' => $user->id,
             'domain' => $domain,
+            'sourcedomain' => $sourcedomain,
         ];
         $response = $this->main->renderTemplate('webfinger_acct.json', $data);
         $this->wellKnown->setResponse($response);

php/federator/cache/cache.php

@@ -13,14 +13,35 @@ namespace Federator\Cache;
  */
 interface Cache extends \Federator\Connector\Connector
 {
+    /**
+     * save remote followers of user
+     *
+     * @param string $user user name
+     * @param \Federator\Data\FedUser[]|false $followers user followers
+     * @return void
+     */
+    public function saveFollowersByUser($user, $followers);
+
+    /**
+     * save remote following for user
+     *
+     * @param string $user user name
+     * @param \Federator\Data\FedUser[]|false $following user following
+     * @return void
+     */
+    public function saveFollowingByUser($user, $following);
+
     /**
      * save remote posts by user
      *
      * @param string $user user name
+     * @param int $min min timestamp
+     * @param int $max max timestamp
+     * @param int $limit limit results
      * @param \Federator\Data\ActivityPub\Common\APObject[]|false $posts user posts
      * @return void
      */
-    public function saveRemotePostsByUser($user, $posts);
+    public function saveRemotePostsByUser($user, $min, $max, $limit, $posts);
 
     /**
      * save remote stats
@@ -39,6 +60,15 @@ 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 $user);
+
     /**
      * save remote user by given session
      *
@@ -48,4 +78,29 @@ interface Cache extends \Federator\Connector\Connector
      * @return void
      */
     public function saveRemoteUserBySession($_session, $_user, $user);
+
+    /**
+     * Save the public key for a given keyId
+     *
+     * @param string $keyId The keyId (e.g., actor URL + #main-key)
+     * @param string $publicKeyPem The public key PEM to cache
+     * @return void
+     */
+    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
+     *
+     * @param string $keyId The keyId (e.g., actor URL + #main-key)
+     * @return string|false The cached public key PEM or false if not found
+     */
+    public function getPublicKey(string $keyId);
 }

php/federator/connector/connector.php

@@ -13,16 +13,32 @@ namespace Federator\Connector;
  */
 interface Connector
 {
+    /**
+     * get followers of given user
+     *
+     * @param string $id user id
+     * @return \Federator\Data\FedUser[]|false
+     */
+    public function getFollowersByUser($id);
+
+    /**
+     * get following of given user
+     *
+     * @param string $id user id
+     * @return \Federator\Data\FedUser[]|false
+     */
+    public function getFollowingByUser($id);
+
     /**
      * get posts by given user
      *
      * @param string $id user id
-     * @param string $minId min ID
-     * @param string $maxId max ID
-
-     * @return \Federator\Data\ActivityPub\Common\APObject[]|false
+     * @param int $min min value
+     * @param int $max max value
+     * @param int $limit maximum number of results
+     * @return \Federator\Data\ActivityPub\Common\Activity[]|false
      */
-    public function getRemotePostsByUser($id, $minId, $maxId);
+    public function getRemotePostsByUser($id, $min, $max, $limit);
 
     /**
      * get remote user by given name
@@ -47,4 +63,32 @@ interface Connector
      * @return \Federator\Data\Stats|false
      */
     public function getRemoteStats();
+
+    /**
+     * Convert jsonData to Activity format
+     *
+     * @param array<string, mixed> $jsonData the json data from our platfrom
+     * @param string $articleId the original id of the article (if applicable)
+     *                           (used to identify the article in the remote system)
+     * @return \Federator\Data\ActivityPub\Common\Activity|false
+     */
+    public function jsonToActivity(array $jsonData, &$articleId);
+
+    /**
+     * send target-friendly json from ActivityPub activity
+     *
+     * @param \Federator\Data\FedUser $sender the user of the sender
+     * @param \Federator\Data\ActivityPub\Common\Activity $activity the activity
+     * @return boolean did we successfully send the activity?
+     */
+    public function sendActivity($sender, $activity);
+
+    /**
+     * check if the headers include a valid signature
+     *
+     * @param string[] $headers the headers
+     * @throws \Federator\Exceptions\PermissionDenied
+     * @return string|\Federator\Exceptions\PermissionDenied
+     */
+    public function checkSignature($headers);
 }

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

@@ -47,7 +47,7 @@ class Activity extends APObject
         return $this;
     }
 
-    public function getAActor() : string
+    public function getAActor(): string
     {
         return $this->aactor;
     }
@@ -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/announce.php

@@ -0,0 +1,41 @@
+<?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 Announce extends Activity
+{
+    public function __construct()
+    {
+        parent::__construct('Announce');
+        parent::addContext('https://www.w3.org/ns/activitystreams');
+    }
+
+    /**
+     * convert internal state to php array
+     *
+     * @return array<string,mixed>
+     */
+    public function toObject()
+    {
+        $return = parent::toObject();
+        $return['type'] = 'Announce';
+        return $return;
+    }
+
+   /**
+     * create object from json
+     *
+     * @param array<string,mixed> $json input json
+     * @return bool true on success
+     */
+    public function fromJson($json)
+    {
+        return parent::fromJson($json);
+    }
+}

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;
 
@@ -347,7 +347,7 @@ class APObject implements \JsonSerializable
     /**
      * set child object
      *
-     * @param APObject $object
+     * @param APObject|string $object
      * @return void
      */
     public function setObject($object)
@@ -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()
     {
@@ -376,6 +376,17 @@ class APObject implements \JsonSerializable
         $this->summary = $summary;
         return $this;
     }
+
+    /**
+     * get summary
+     *
+     * @return string summary
+     */
+    public function getSummary()
+    {
+        return $this->summary;
+    }
+
     /**
      * set type
      *
@@ -459,6 +470,16 @@ class APObject implements \JsonSerializable
         return $this;
     }
 
+    /**
+     * get name
+     *
+     * @return string name
+     */
+    public function getName() : string
+    {
+        return $this->name;
+    }
+
     /**
      * add Image
      *
@@ -647,7 +668,7 @@ class APObject implements \JsonSerializable
         if (array_key_exists('duration', $json)) {
             try {
                 $this->duration = new \DateInterval($json['duration']);
-            } catch (\Exception $unused_e) {
+            } catch (\Throwable $unused_e) {
                 error_log("error parsing duration ". $json['duration']);
             }
         }
@@ -750,8 +771,8 @@ class APObject implements \JsonSerializable
         if (array_key_exists('mediaType', $json)) {
             $this->mediaType = $json['mediaType'];
         }
-        if (array_key_exists('object', $json)) {
-            $this->object = \Federator\Data\ActivityPub\Factory::newFromJson($json['object'], "");
+        if (array_key_exists('object', $json)) { // some actPub servers send strings in the object field
+            $this->object = is_array($json['object']) ? \Federator\Data\ActivityPub\Factory::newFromJson($json['object'], "") : $json['object'];
         }
         if (array_key_exists('sensitive', $json)) {
             $this->sensitive = $json['sensitive'];
@@ -773,7 +794,7 @@ class APObject implements \JsonSerializable
      * {@inheritDoc}
      * @see JsonSerializable::jsonSerialize()
      */
-    public function jsonSerialize()
+    public function jsonSerialize(): mixed
     {
         return $this->toObject();
     }
@@ -875,7 +896,7 @@ class APObject implements \JsonSerializable
             $return['tag'] = $tags;
         }
         if ($this->updated > 0) {
-            $return['updated'] = gmdate("Y-m-d\TH:i:S\Z", $this->updated);
+            $return['updated'] = gmdate("Y-m-d\TH:i:s\Z", $this->updated);
         }
         if ($this->url !== '') {
             $return['url'] = $this->url;
@@ -890,7 +911,7 @@ 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/collection.php

@@ -10,7 +10,7 @@ namespace Federator\Data\ActivityPub\Common;
 
 class Collection extends APObject
 {
-    protected int $totalItems = 0;
+    protected int $totalItems = -1;
     private string $first = '';
     private string $last = '';
 
@@ -28,7 +28,7 @@ class Collection extends APObject
     {
         $return = parent::toObject();
         $return['type'] = 'Collection';
-        if ($this->totalItems > 0) {
+        if ($this->totalItems >= 0) {
             $return['totalItems'] = $this->totalItems;
         }
         if ($this->first !== '') {
@@ -48,20 +48,48 @@ class Collection extends APObject
      */
     public function fromJson($json)
     {
-        return parent::fromJson($json);
+        $success = parent::fromJson($json);
+        if (!$success) {
+            return false;
+        }
+        if (array_key_exists('totalItems', $json)) {
+            $this->totalItems = $json['totalItems'];
+        }
+        if (array_key_exists('first', $json)) {
+            $this->first = $json['first'];
+        }
+        if (array_key_exists('last', $json)) {
+            $this->last = $json['last'];
+        }
+        return true;
     }
 
-    public function count() : int
+    /**
+     * set total items
+     *
+     * @param int $totalItems total items
+     */
+    public function setTotalItems(int $totalItems): void
+    {
+        $this->totalItems = $totalItems;
+    }
+
+    public function getTotalItems(): int
     {
         return $this->totalItems;
     }
 
-    public function setFirst(string $url) : void
+    public function getFirst(): string
+    {
+        return $this->first;
+    }
+
+    public function setFirst(string $url): void
     {
         $this->first = $url;
     }
 
-    public function setLast(string $url) : void
+    public function setLast(string $url): void
     {
         $this->last = $url;
     }

php/federator/data/activitypub/common/create.php

@@ -26,7 +26,9 @@ class Create extends Activity
         $return = parent::toObject();
         $return['type'] = 'Create';
         // overwrite id from url
-        $return['id'] = $this->getURL();
+        if ($this->getURL() !== '') {
+            $return['id'] = $this->getURL();
+        }
         return $return;
     }
 

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

@@ -0,0 +1,36 @@
+<?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
+{
+    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
+    {
+        return parent::fromJson($json);
+    }
+    /**
+     * convert internal state to php array
+     * @return array<string,mixed>
+     */
+    public function toObject()
+    {
+        $return = parent::toObject();
+        return $return;
+    }
+}

php/federator/data/activitypub/common/dislike.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 Dislike extends Activity
+{
+    public function __construct()
+    {
+        parent::__construct('Dislike');
+        parent::addContext('https://www.w3.org/ns/activitystreams');
+    }
+}

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

@@ -0,0 +1,55 @@
+<?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 getObject(): string
+    {
+        return $this->object;
+    }
+
+    public function __construct()
+    {
+        parent::__construct("Follow");
+        parent::addContext('https://www.w3.org/ns/activitystreams');
+    }
+
+    public function fromJson($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/followers.php

@@ -0,0 +1,53 @@
+<?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 Followers extends OrderedCollectionPage
+{
+    public function __construct()
+    {
+        parent::__construct();
+        parent::addContext('https://www.w3.org/ns/activitystreams');
+    }
+
+    /**
+     * set items
+     *
+     * @param string[] $items the items in the collection
+     * @return void
+     */
+    public function setItems(&$items)
+    {
+        // Optionally: type check that all $items are Activity objects
+        $this->orderedItems = $items;
+        $this->totalItems = sizeof($items);
+    }
+
+    /**
+     * convert internal state to php array
+     *
+     * @return array<string,mixed>
+     */
+    public function toObject()
+    {
+        $return = parent::toObject();
+        return $return;
+    }
+
+    /**
+     * create object from json
+     *
+     * @param array<string,mixed> $json input json
+     * @return bool true on success
+     */
+    public function fromJson($json)
+    {
+        return parent::fromJson($json);
+    }
+}

php/federator/data/activitypub/common/following.php

@@ -0,0 +1,53 @@
+<?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 Following extends OrderedCollectionPage
+{
+    public function __construct()
+    {
+        parent::__construct();
+        parent::addContext('https://www.w3.org/ns/activitystreams');
+    }
+
+    /**
+     * set items
+     *
+     * @param string[] $items the items in the collection
+     * @return void
+     */
+    public function setItems(&$items)
+    {
+        // Optionally: type check that all $items are Activity objects
+        $this->orderedItems = $items;
+        $this->totalItems = sizeof($items);
+    }
+
+    /**
+     * convert internal state to php array
+     *
+     * @return array<string,mixed>
+     */
+    public function toObject()
+    {
+        $return = parent::toObject();
+        return $return;
+    }
+
+    /**
+     * create object from json
+     *
+     * @param array<string,mixed> $json input json
+     * @return bool true on success
+     */
+    public function fromJson($json)
+    {
+        return parent::fromJson($json);
+    }
+}

php/federator/data/activitypub/common/inbox.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 Inbox extends OrderedCollectionPage
+{
+    public function __construct()
+    {
+        parent::__construct();
+        parent::addContext('https://www.w3.org/ns/activitystreams');
+        parent::addContexts([
+            "ostatus" => "http://ostatus.org#",
+            "atomUri" => "ostatus:atomUri",
+            "inReplyToAtomUri" => "ostatus:inReplyToAtomUri",
+            "conversation" => "ostatus:conversation",
+            "sensitive" => "as:sensitive",
+            "toot" => "http://joinmastodon.org/ns#",
+            "votersCount" => "toot:votersCount",
+            "Hashtag" => "as:Hashtag"
+        ]);
+    }
+
+    /**
+     * convert internal state to php array
+     *
+     * @return array<string,mixed>
+     */
+    public function toObject()
+    {
+        $return = parent::toObject();
+        return $return;
+    }
+
+    /**
+     * create object from json
+     *
+     * @param array<string,mixed> $json input json
+     * @return bool true on success
+     */
+    public function fromJson($json)
+    {
+        return parent::fromJson($json);
+    }
+}

php/federator/data/activitypub/common/like.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 Like extends Activity
+{
+    public function __construct()
+    {
+        parent::__construct('Like');
+        parent::addContext('https://www.w3.org/ns/activitystreams');
+    }
+}

php/federator/data/activitypub/common/orderedcollection.php

@@ -13,9 +13,9 @@ class OrderedCollection extends Collection
     /**
      * nested items
      *
-     * @var APObject[]
+     * @var APObject[]|string[]
      */
-    protected $items = [];
+    protected $orderedItems = [];
 
     public function __construct()
     {
@@ -32,9 +32,13 @@ class OrderedCollection extends Collection
     {
         $return = parent::toObject();
         $return['type'] = 'OrderedCollection';
-        if ($this->totalItems > 0) {
-            foreach ($this->items as $item) {
-                $return['OrderedItems'][] = $item->toObject();
+        if (sizeof($this->orderedItems) > 0) {
+            foreach ($this->orderedItems as $item) {
+                if (is_string($item)) {
+                    $return['orderedItems'][] = $item;
+                } elseif (is_object($item)) {
+                    $return['orderedItems'][] = $item->toObject();
+                }
             }
         }
         return $return;
@@ -48,44 +52,63 @@ class OrderedCollection extends Collection
      */
     public function fromJson($json)
     {
-        return parent::fromJson($json);
+        $success = parent::fromJson($json);
+        if (!$success) {
+            return false;
+        }
+        if (array_key_exists('orderedItems', $json)) {
+            foreach ($json['orderedItems'] as $item) {
+                $obj = \Federator\Data\ActivityPub\Factory::newActivityFromJson($item);
+                if ($obj !== false) {
+                    $this->orderedItems[] = $obj;
+                }
+            }
+        }
+
+        return true;
     }
 
-    public function append(APObject &$item) : void
+    /**
+     * add item to collection
+     * @param APObject|string $item
+     */
+    public function append(&$item): void
     {
-        $this->items[] = $item;
-        $this->totalItems = sizeof($this->items);
+        $this->orderedItems[] = $item;
     }
 
     /**
      * get item with given index
      *
-     * @return APObject|false
+     * @return APObject|string|false
      */
     public function get(int $index)
     {
         if ($index >= 0) {
-            if ($index >= $this->totalItems) {
+            if ($index >= sizeof($this->orderedItems)) {
                 return false;
             }
-            return $this->items[$index];
+            return $this->orderedItems[$index];
         } else {
-            if ($this->totalItems+ $index < 0) {
+            if (sizeof($this->orderedItems) + $index < 0) {
                 return false;
             }
-            return $this->items[$this->totalItems + $index];
+            return $this->orderedItems[sizeof($this->orderedItems) + $index];
         }
     }
 
+    public function getCount(): int
+    {
+        return sizeof($this->orderedItems);
+    }
     /**
      * set items
      *
-     * @param APObject[] $items
+     * @param APObject[]|string[] $items
      * @return void
      */
     public function setItems(&$items)
     {
-        $this->items = $items;
-        $this->totalItems = sizeof($items);
+        $this->orderedItems = $items;
     }
 }

php/federator/data/activitypub/common/orderedcollectionpage.php

@@ -19,6 +19,7 @@ class OrderedCollectionPage extends OrderedCollection
     {
         parent::__construct();
         parent::addContext('https://www.w3.org/ns/activitystreams');
+        $this->setType('OrderedCollectionPage');
     }
 
     /**
@@ -38,7 +39,7 @@ class OrderedCollectionPage extends OrderedCollection
         if ($this->partOf !== '') {
             $return['partOf'] = $this->partOf;
         }
-        $return['type'] = 'OrderedCollectionPage';
+        $return['type'] = $this->getType();
         return $return;
     }
 
@@ -50,7 +51,29 @@ class OrderedCollectionPage extends OrderedCollection
      */
     public function fromJson($json)
     {
-        return parent::fromJson($json);
+        $success = parent::fromJson($json);
+        if (!$success) {
+            return false;
+        }
+        if (array_key_exists('next', $json)) {
+            $this->next = $json['next'];
+        }
+        if (array_key_exists('prev', $json)) {
+            $this->prev = $json['prev'];
+        }
+        if (array_key_exists('partOf', $json)) {
+            $this->partOf = $json['partOf'];
+        }
+        return true;
+    }
+
+    /**
+     * get next url
+     * @return string next URL
+     */
+    public function getNext()
+    {
+        return $this->next;
     }
 
     /**

php/federator/data/activitypub/common/outbox.php

@@ -4,6 +4,7 @@
  * SPDX-License-Identifier: GPL-3.0-or-later
  *
  * @author Sascha Nitsch (grumpydeveloper)
+ * @author Yannis Vogel (vogeldevelopment)
  **/
 
 namespace Federator\Data\ActivityPub\Common;
@@ -26,6 +27,17 @@ class Outbox extends OrderedCollectionPage
         ]);
     }
 
+    /**
+     * set items
+     *
+     * @param \Federator\Data\ActivityPub\Common\APObject[] $items the items in the collection
+     */
+    public function setItems(&$items)
+    {
+        // Optionally: type check that all $items are Activity objects
+        $this->orderedItems = $items;
+    }
+
     /**
      * convert internal state to php array
      *

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/common/undo.php

@@ -0,0 +1,41 @@
+<?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 Undo extends Activity
+{
+    public function __construct()
+    {
+        parent::__construct('Undo');
+        parent::addContext('https://www.w3.org/ns/activitystreams');
+    }
+
+    /**
+     * convert internal state to php array
+     *
+     * @return array<string,mixed>
+     */
+    public function toObject()
+    {
+        $return = parent::toObject();
+        $return['type'] = 'Undo';
+        return $return;
+    }
+
+   /**
+     * create object from json
+     *
+     * @param array<string,mixed> $json input json
+     * @return bool true on success
+     */
+    public function fromJson($json)
+    {
+        return parent::fromJson($json);
+    }
+}

php/federator/data/activitypub/common/unsupported.txt

@@ -0,0 +1,16 @@
+Array
+(
+    [type] => Document
+    [mediaType] => image/jpeg
+    [url] => https://noc.social/system/media_attachments/files/112/350/286/131/419/396/original/26ab9c8a4ab13f16.jpg
+    [name] => Screenshot Zeitleiste aus kdenlive.
+    [blurhash] => UC8|^tSwI-bu-taeRiaeu5e.aJjGsBWnR*jH
+    [focalPoint] => Array
+        (
+            [0] => -0.01
+            [1] => -0.79
+        )
+
+    [width] => 1333
+    [height] => 651
+)

php/federator/data/activitypub/common/update.php

@@ -0,0 +1,45 @@
+<?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 Update extends Activity
+{
+    public function __construct()
+    {
+        parent::__construct('Update');
+        parent::addContext('https://www.w3.org/ns/activitystreams');
+    }
+
+    /**
+     * convert internal state to php array
+     *
+     * @return array<string,mixed>
+     */
+    public function toObject()
+    {
+        $return = parent::toObject();
+        $return['type'] = 'Update';
+        // overwrite id from url
+        if ($this->getURL() !== '') {
+            $return['id'] = $this->getURL();
+        }
+        return $return;
+    }
+
+   /**
+     * create object from json
+     *
+     * @param array<string,mixed> $json input json
+     * @return bool true on success
+     */
+    public function fromJson($json)
+    {
+        return parent::fromJson($json);
+    }
+}

php/federator/data/activitypub/common/vote.php

@@ -0,0 +1,27 @@
+<?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 Vote extends APObject
+{
+    public function __construct()
+    {
+        parent::__construct('Vote');
+    }
+
+    /**
+     * create object from json
+     * @param mixed $json input
+     * @return bool true on success
+     */
+    public function fromJson($json)
+    {
+        return parent::fromJson($json);
+    }
+}

php/federator/data/activitypub/factory.php

@@ -16,7 +16,7 @@ class Factory
 
     /**
      * create object tree from json
-     * @param array<string, mixed> $json input json
+     * @param array<string, mixed>|mixed $json input json
      * @return Common\APObject|null object or false on error
      */
     public static function newFromJson($json, string $jsonstring)
@@ -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;
@@ -39,21 +42,45 @@ 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;
-            /*case 'Note':
+            case 'Note':
                 $return = new Common\Note();
                 break;
-            case 'Question':
-                $return = new \Common\Question();
+            case 'Outbox':
+                $return = new Common\Outbox();
+                break;
+            case 'Vote':
+                $return = new Common\Vote();
+                break;
+            case 'Like':
+                $return = new Common\Like();
+                break;
+            case 'Dislike':
+                $return = new Common\Dislike();
+                break;
+            case 'Inbox':
+                $return = new Common\Inbox();
+                break;
+            case 'OrderedCollection':
+                $return = new Common\OrderedCollection();
+                break;
+            case 'OrderedCollectionPage':
+                $return = new Common\OrderedCollectionPage();
+                break;
+            case 'Tombstone':
+                $return = new Common\APObject("Tombstone");
+                break;
+            /*case 'Question':
+                $return = new Common\Question();
                 break;
             case 'Video':
-                $return = new \Common\Video();
+                $return = new Common\Video();
                 break;*/
             default:
                 error_log("newFromJson: unknown type: '" . $json['type'] . "' " . $jsonstring);
@@ -77,9 +104,7 @@ class Factory
         }
         //$return = false;
         switch ($json['type']) {
-            case 'MakePhanHappy':
-                break;
-/*            case 'Accept':
+            case 'Accept':
                 $return = new Common\Accept();
                 break;
             case 'Announce':
@@ -91,18 +116,30 @@ class Factory
             case 'Delete':
                 $return = new Common\Delete();
                 break;
+            case 'Like':
+                $return = new Common\Like();
+                break;
+            case 'Dislike':
+                $return = new Common\Dislike();
+                break;
             case 'Follow':
                 $return = new Common\Follow();
                 break;
+            case 'Reject':
+                $return = new Common\Reject();
+                break;
             case 'Undo':
-                $return = new \Common\Undo();
-                break;*/
+                $return = new Common\Undo();
+                break;
+            case 'Update':
+                $return = new Common\Update();
+                break;
             default:
-                error_log("newActivityFromJson " . print_r($json, true));
+                error_log("newActivityFromJson unsupported type: " . print_r($json, true));
         }
-        /*if ($return !== false && $return->fromJson($json) !== null) {
+        if (isset($return) && $return->fromJson($json) !== null) {
             return $return;
-        }*/
+        }
         return false;
     }
 }

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/article.php

@@ -0,0 +1,67 @@
+<?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 articles
+ */
+class Article
+{
+    /**
+     * Convert an Article to a Note
+     *
+     * @param \Federator\Data\ActivityPub\Common\Article $article
+     * @return \Federator\Data\ActivityPub\Common\Note
+     *      The generated note
+     */
+    public static function convertToNote($article)
+    {
+        $note = new \Federator\Data\ActivityPub\Common\Note();
+        $note->setId($article->getId())
+            ->setURL($article->getURL());
+        $note->setContent($article->getContent());
+        $note->setSummary($article->getSummary());
+        $note->setPublished($article->getPublished());
+        $note->setName($article->getName());
+        $note->setAttributedTo($article->getAttributedTo());
+        foreach ($article->getTo() as $to) {
+            $note->addTo($to);
+        }
+        foreach ($article->getCc() as $cc) {
+            $note->addCc($cc);
+        }
+        return $note;
+    }
+
+    /** Conditionally convert article to a note
+     *
+     * @param \Federator\Data\ActivityPub\Common\Article $article
+     * @param string $targetUrl
+     *      The target URL for the activity (e.g. mastodon.social)
+     * @return \Federator\Data\ActivityPub\Common\Note|\Federator\Data\ActivityPub\Common\Article
+     *      The generated note on success, false on failure
+     */
+    public static function conditionalConvertToNote($article, $targetUrl)
+    {
+        $supportFile = file_get_contents($_SERVER['DOCUMENT_ROOT'] . '../formatsupport.json');
+        if ($supportFile === false) {
+            error_log("Article::conditionalConvertToNote Failed to read support file for article conversion.");
+            return $article; // Fallback to original article if file read fails
+        }
+        $supportlist = json_decode($supportFile, true);
+
+        if (!isset($supportlist['activitypub']['article']) ||
+            !is_array($supportlist['activitypub']['article']) ||
+            !in_array($targetUrl, $supportlist['activitypub']['article'], true)
+        ) {
+            return self::convertToNote($article); // Articles are not supported for this target
+        }
+        return $article; // Articles are supported, return as is
+    }
+}

php/federator/dio/feduser.php

@@ -0,0 +1,469 @@
+<?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 $_user user/profile name
+     * @return void
+     */
+    protected static function addUserToDB($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('FedUser::addLocalUser Failed to prepare statement');
+        }
+        $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('FedUser::addLocalUser Failed to prepare create statement');
+            }
+            $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('FedUser::extendUser Failed to prepare update statement');
+            }
+            $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('FedUser::extendUser Failed to prepare statement');
+        }
+        $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 || $validuntil < time()) {
+            self::addUserToDB($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`, ';
+        $sql .= '`followersurl`, `followingurl`, `publickeyid`, `outboxurl`';
+        $sql .= ' from fedusers where `id`=? and `validuntil`>=now()';
+        $stmt = $dbh->prepare($sql);
+        if ($stmt === false) {
+            throw new \Federator\Exceptions\ServerError('FedUser::getUserByName Failed to prepare statement');
+        }
+        $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('FedUser::getUserByName Failed to fetch webfinger for '
+                        . $_name);
+                }
+                $r = json_decode($response, true);
+                if ($r === false || $r === null || !is_array($r)) {
+                    throw new \Federator\Exceptions\ServerError('FedUser::getUserByName Failed to decode webfinger for '
+                        . $_name);
+                }
+                // get the webwinger user url and fetch the user
+                if (isset($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('FedUser::getUserByName Failed to find self link '
+                        . 'in webfinger for ' . $_name);
+                }
+            } else {
+                $remoteURL = $_name;
+            }
+            // 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('FedUser::getUserByName Failed to fetch user from '
+                    . 'remoteUrl for ' . $_name);
+            }
+            $r = json_decode($response, true);
+            if ($r === false || $r === null || !is_array($r)) {
+                throw new \Federator\Exceptions\ServerError('FedUser::getUserByName Failed to decode user for '
+                    . $_name);
+            }
+            $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('FedUser::getUserByName Failed to encode userdata '
+                    . $_name);
+            }
+            $user = \Federator\Data\FedUser::createFromJson($data);
+        }
+
+        if ($cache !== null && $user !== false) {
+            if ($user->id !== null && $user->actorURL !== null) {
+                self::addUserToDB($dbh, $user, $_name);
+            }
+            $cache->saveRemoteFedUserByName($_name, $user);
+        }
+        if ($user === false) {
+            throw new \Federator\Exceptions\ServerError('FedUser::getUserByName User not found');
+        }
+        return $user;
+    }
+
+    /**
+     * handle post call for specific user
+     *
+     * @param \Federator\Main $main main instance
+     * @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 that triggered the post
+     * @param string $_recipientId recipient of the post
+     * @param \Federator\Data\ActivityPub\Common\Activity $inboxActivity the activity that we received
+     * @return boolean response
+     */
+    public static function inboxForUser($main, $dbh, $connector, $cache, $_user, $_recipientId, $inboxActivity)
+    {
+        if (!isset($_user)) {
+            error_log('Inbox::postForUser no user given');
+            return false;
+        }
+
+        // get sender
+        $user = \Federator\DIO\FedUser::getUserByName(
+            $dbh,
+            $_user,
+            $cache
+        );
+        if ($user === null || $user->id === null) {
+            error_log('Inbox::postForUser couldn\'t find user: ' . $_user);
+            return false;
+        }
+
+        $type = strtolower($inboxActivity->getType());
+
+        if ($_recipientId === '') {
+            if ($type === 'undo' || $type === 'delete') {
+                switch ($type) {
+                    case 'delete':
+                        // Delete Note/Post
+                        $object = $inboxActivity->getObject();
+                        if (is_string($object)) {
+                            \Federator\DIO\Posts::deletePost($dbh, $object);
+                        } elseif (is_object($object)) {
+                            $objectId = $object->getID();
+                            \Federator\DIO\Posts::deletePost($dbh, $objectId);
+                        } else {
+                            error_log('Inbox::postForUser Error in Delete Post for user ' . $user->id
+                                . ', object is not a string or object');
+                            error_log(' object of type ' . gettype($object));
+                            return false;
+                        }
+                        break;
+
+                    case 'undo':
+                        $object = $inboxActivity->getObject();
+                        if (is_object($object)) {
+                            switch (strtolower($object->getType())) {
+                                case 'like':
+                                case 'dislike':
+                                    // Undo Like/Dislike (remove like/dislike)
+                                    $targetId = $object->getID();
+                                    // \Federator\DIO\Votes::removeVote($dbh, $user->id, $targetId, 'dislike');
+                                    \Federator\DIO\Posts::deletePost($dbh, $targetId);
+                                    break;
+                                case 'note':
+                                case 'article':
+                                    // Undo Note (remove note)
+                                    $noteId = $object->getID();
+                                    \Federator\DIO\Posts::deletePost($dbh, $noteId);
+                                    break;
+                            }
+                        }
+                        break;
+
+                    default:
+                        error_log('Inbox::postForUser Unhandled activity type ' . $type . ' for user ' . $user->id);
+                        break;
+                }
+
+                return true;
+            }
+        }
+
+        $atPos = strpos($_recipientId, '@');
+        if ($atPos !== false) {
+            $_recipientId = substr($_recipientId, 0, $atPos);
+        }
+
+        // get recipient
+        $recipient = \Federator\DIO\User::getUserByName(
+            $dbh,
+            $_recipientId,
+            $connector,
+            $cache
+        );
+        if ($recipient === null || $recipient->id === null) {
+            error_log('Inbox::postForUser couldn\'t find recipient: ' . $_recipientId);
+            return false;
+        }
+
+        $rootDir = $_SERVER['DOCUMENT_ROOT'] .  '../';
+        // Save the raw input and parsed JSON to a file for inspection
+        file_put_contents(
+            $rootDir . 'logs/inbox_' . $recipient->id . '.log',
+            date('Y-m-d H:i:s') . ": ==== POST " . $recipient->id . " Inbox Activity ====\n"
+                . json_encode($inboxActivity, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT) . "\n\n",
+            FILE_APPEND
+        );
+
+        switch ($type) {
+            case 'follow':
+                $success = \Federator\DIO\Followers::addExternalFollow(
+                    $dbh,
+                    $inboxActivity->getID(),
+                    $user->id,
+                    $recipient->id
+                );
+
+                if ($success === true) {
+                    // send accept back
+                    $accept = new \Federator\Data\ActivityPub\Common\Accept();
+                    $local = $inboxActivity->getObject();
+                    if (is_string($local)) {
+                        $accept->setAActor($local);
+                        $id = bin2hex(openssl_random_pseudo_bytes(4));
+                        $accept->setID($local . '#accepts/follows/' . $id);
+                        $obj = new \Federator\Data\ActivityPub\Common\Activity($inboxActivity->getType());
+                        $config = $main->getConfig();
+                        $ourhost = $config['generic']['protocol'] . '://' . $config['generic']['externaldomain'];
+                        $obj->setID($ourhost . '/' . $id);
+                        $obj->setAActor($inboxActivity->getAActor());
+                        $obj->setObject($local);
+                        $accept->setObject($obj);
+                        // send
+                        \Federator\DIO\Server::sendActivity($dbh, $ourhost, $recipient, $user, $accept);
+                    }
+                } else {
+                    error_log('Inbox::postForUser Failed to add follower for user ' . $user->id);
+                }
+                break;
+
+            case 'delete':
+                // Delete Note/Post
+                $object = $inboxActivity->getObject();
+                if (is_string($object)) {
+                    \Federator\DIO\Posts::deletePost($dbh, $object);
+                } elseif (is_object($object)) {
+                    $objectId = $object->getID();
+                    \Federator\DIO\Posts::deletePost($dbh, $objectId);
+                }
+                break;
+
+            case 'undo':
+                $object = $inboxActivity->getObject();
+                if (is_object($object)) {
+                    switch (strtolower($object->getType())) {
+                        case 'follow':
+                            $success = false;
+                            if ($object instanceof \Federator\Data\ActivityPub\Common\Activity) {
+                                $actor = $object->getAActor();
+                                if ($actor !== '') {
+                                    $success = \Federator\DIO\Followers::removeFollow($dbh, $user->id, $recipient->id);
+                                }
+                            }
+                            if ($success === false) {
+                                error_log('Inbox::postForUser Failed to remove follower for user ' . $user->id);
+                            }
+                            break;
+                        case 'like':
+                        case 'dislike':
+                            // Undo Like/Dislike (remove like/dislike)
+                            $targetId = $object->getID();
+                            \Federator\DIO\Votes::removeVote($dbh, $user->id, $targetId);
+                            // \Federator\DIO\Posts::deletePost($dbh, $targetId);
+                            break;
+                        case 'note':
+                            // Undo Note (remove note)
+                            $noteId = $object->getID();
+                            \Federator\DIO\Posts::deletePost($dbh, $noteId);
+                            break;
+                    }
+                }
+                break;
+
+            case 'like':
+            case 'dislike':
+                // Add Like/Dislike
+                $targetId = $inboxActivity->getObject();
+                if (is_string($targetId)) {
+                    \Federator\DIO\Votes::addVote($dbh, $user->id, $targetId, $type);
+                } else {
+                    error_log('Inbox::postForUser Error in Add Like/Dislike for user ' . $user->id
+                        . ', targetId is not a string');
+                    return false;
+                }
+                break;
+
+            case 'create':
+            case 'update':
+                $object = $inboxActivity->getObject();
+                if (is_object($object)) {
+                    switch (strtolower($object->getType())) {
+                        case 'note':
+                            \Federator\DIO\Posts::savePost($dbh, $user->id, $inboxActivity);
+                            break;
+                        case 'article':
+                            \Federator\DIO\Posts::savePost($dbh, $user->id, $inboxActivity);
+                            break;
+                        default:
+                            \Federator\DIO\Posts::savePost($dbh, $user->id, $inboxActivity);
+                            break;
+                    }
+                }
+                break;
+            default:
+                error_log('Inbox::postForUser Unhandled activity type $type for user ' . $user->id);
+                break;
+        }
+        return true;
+    }
+}

php/federator/dio/followers.php

@@ -0,0 +1,530 @@
+<?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 followers
+ */
+class Followers
+{
+    /**
+     * get followers of user
+     *
+     * @param \mysqli $dbh
+     *          database handle
+     * @param string $id
+     *          user id
+     * @param \Federator\Connector\Connector $connector
+     *          connector to fetch use with
+     * @param \Federator\Cache\Cache|null $cache
+     *          optional caching service
+     * @return \Federator\Data\FedUser[]
+     */
+    public static function getFollowersByUser($dbh, $id, $connector, $cache)
+    {
+        // ask cache
+        if ($cache !== null) {
+            $followers = $cache->getFollowersByUser($id);
+            if ($followers !== false) {
+                return $followers;
+            }
+        }
+        $followers = [];
+        $sql = 'select source_user from follows where target_user = ?';
+        $stmt = $dbh->prepare($sql);
+        if ($stmt === false) {
+            throw new \Federator\Exceptions\ServerError('Followers::getFollowersByUser Failed to prepare statement');
+        }
+        $stmt->bind_param('s', $id);
+        $stmt->execute();
+        $followerIds = [];
+        $stmt->bind_result($sourceUser);
+        while ($stmt->fetch()) {
+            $followerIds[] = $sourceUser;
+        }
+        $stmt->close();
+        foreach ($followerIds as $followerId) {
+            try {
+                $user = \Federator\DIO\FedUser::getUserByName(
+                    $dbh,
+                    $followerId,
+                    $cache,
+                );
+            } catch (\Throwable $e) {
+                error_log('Followers::getFollowersByUser Exception: ' . $e->getMessage());
+                continue; // Skip this user if an exception occurs
+            }
+            if ($user !== false && $user->id !== null) {
+                $followers[] = $user;
+            }
+        }
+
+        if ($followers === []) {
+            // ask connector for user-id
+            $followers = $connector->getFollowersByUser($id);
+            if ($followers === false) {
+                $followers = [];
+            }
+        }
+        // save followers to cache
+        if ($cache !== null) {
+            $cache->saveFollowersByUser($id, $followers);
+        }
+        return $followers;
+    }
+    /**
+     * get following for user - who does the user follow
+     *
+     * @param \mysqli $dbh
+     *          database handle
+     * @param string $id
+     *          user id
+     * @param \Federator\Connector\Connector $connector
+     *          connector to fetch use with
+     * @param \Federator\Cache\Cache|null $cache
+     *          optional caching service
+     * @return \Federator\Data\FedUser[]
+     */
+    public static function getFollowingByUser($dbh, $id, $connector, $cache)
+    {
+        // ask cache
+        if ($cache !== null) {
+            $following = $cache->getFollowingByUser($id);
+            if ($following !== false) {
+                return $following;
+            }
+        }
+        $following = [];
+        $sql = 'select target_user from follows where source_user = ?';
+        $stmt = $dbh->prepare($sql);
+        if ($stmt === false) {
+            throw new \Federator\Exceptions\ServerError('Followers::getFollowingForUser Failed to prepare statement');
+        }
+        $stmt->bind_param('s', $id);
+        $stmt->execute();
+        $followingIds = [];
+        $stmt->bind_result($sourceUser);
+        while ($stmt->fetch()) {
+            $followingIds[] = $sourceUser;
+        }
+        $stmt->close();
+        foreach ($followingIds as $followingId) {
+            try {
+                $user = \Federator\DIO\FedUser::getUserByName(
+                    $dbh,
+                    $followingId,
+                    $cache,
+                );
+            } catch (\Throwable $e) {
+                error_log('Followers::getFollowingByUser Exception: ' . $e->getMessage());
+                continue; // Skip this user if an exception occurs
+            }
+            if ($user !== false && $user->id !== null) {
+                $following[] = $user;
+            }
+        }
+
+        if ($following === []) {
+            // ask connector for user-id
+            $following = $connector->getFollowingByUser($id);
+            if ($following === false) {
+                $following = [];
+            }
+        }
+        // save posts to DB
+        if ($cache !== null) {
+            $cache->saveFollowingByUser($id, $following);
+        }
+        return $following;
+    }
+
+    /**
+     * get followers of federated external user (e.g. mastodon)
+     *
+     * @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('Followers::getFollowersByFedUser Failed to prepare statement');
+        }
+        $stmt->bind_param("s", $id);
+        $stmt->execute();
+        $followerIds = [];
+        $stmt->bind_result($sourceUser);
+        while ($stmt->fetch()) {
+            $followerIds[] = $sourceUser;
+        }
+        foreach ($followerIds as $followerId) {
+            try {
+                $user = \Federator\DIO\User::getUserByName(
+                    $dbh,
+                    $followerId,
+                    $connector,
+                    $cache
+                );
+            } catch (\Throwable $e) {
+                error_log('Followers::getFollowersByFedUser Exception: ' . $e->getMessage());
+                continue; // Skip this user if an exception occurs
+            }
+            if ($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('Followers::sendFollowRequest Failed to get database handle');
+        }
+        $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('Followers::addFollow Failed to prepare statement');
+        }
+        $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('Followers::addFollow Failed to prepare id-check'
+                . 'statement');
+            }
+            $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('Followers::addFollow Failed to prepare insert statement');
+        }
+        $stmt->bind_param('sss', $idurl, $sourceUser, $targetUserId);
+        $stmt->execute();
+        $stmt->close();
+        return $idurl; // Return the generated follow ID
+    }
+
+    /**
+     * add follow
+     *
+     * @param \mysqli $dbh database handle
+     * @param string $followId the follow ID to use (should be an external url)
+     * @param string $sourceUserId source user id
+     * @param string $targetUserId target user id
+     * @return boolean true on success, false on failure
+     */
+    public static function addExternalFollow($dbh, $followId, $sourceUserId, $targetUserId)
+    {
+        // 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('Followers::addExternalFollow Failed to prepare statement');
+        }
+        $stmt->bind_param('ss', $sourceUserId, $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
+        }
+
+        // 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('Followers::addExternalFollow Failed to prepare insert '
+                . 'statement');
+        }
+        $stmt->bind_param('sss', $followId, $sourceUserId, $targetUserId);
+        $stmt->execute();
+        $stmt->close();
+        return true;
+    }
+
+    /**
+     * generate new follow id
+     *
+     * @param \mysqli $dbh database handle
+     * @param string $hostUrl the host URL (e.g. federator URL)
+     * @return string the new follow id
+     */
+    public static function generateNewFollowId($dbh, $hostUrl)
+    {
+        // Generate a new unique follow ID
+        do {
+            $newId = bin2hex(openssl_random_pseudo_bytes(16));
+            $newIdUrl = $hostUrl . '/' . $newId;
+
+            // 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('Followers::generateNewFollowId Failed to prepare id-check'
+                    . ' statement');
+            }
+            $stmt->bind_param('s', $newIdUrl);
+            $foundId = 0;
+            $ret = $stmt->bind_result($foundId);
+            $stmt->execute();
+            if ($ret) {
+                $stmt->fetch();
+            }
+            $stmt->close();
+        } while ($foundId > 0);
+
+        return $newIdUrl;
+    }
+
+    /**
+     * remove follow
+     *
+     * @param \mysqli $dbh database handle
+     * @param string $sourceUser source user id
+     * @param string $targetUserId target user id
+     * @return string|false removed followId on success, false on failure
+     */
+    public static function removeFollow($dbh, $sourceUser, $targetUserId)
+    {
+        // Combine retrieval and removal in one query using MySQL's RETURNING (if supported)
+        $sql = 'delete from follows where source_user = ? and target_user = ? RETURNING id';
+        $stmt = $dbh->prepare($sql);
+        if ($stmt !== false) {
+            $stmt->bind_param('ss', $sourceUser, $targetUserId);
+            if ($stmt->execute()) {
+                $stmt->bind_result($followId);
+                if ($stmt->fetch() === true) {
+                    $stmt->close();
+                    if (!empty($followId)) {
+                        return $followId;
+                    } else {
+                        return false;
+                    }
+                }
+            }
+            $stmt->close();
+        } else {
+            // Fallback for MySQL versions that do not support RETURNING
+            // First, fetch the id of the follow to be removed
+            $sql = 'select id from follows where source_user = ? and target_user = ?';
+            $stmt = $dbh->prepare($sql);
+            if ($stmt === false) {
+                throw new \Federator\Exceptions\ServerError('Followers::removeFollow Failed to prepare select '
+                    . 'statement');
+            }
+            $stmt->bind_param('ss', $sourceUser, $targetUserId);
+            $stmt->execute();
+            $stmt->bind_result($followId);
+            $found = $stmt->fetch();
+            $stmt->close();
+
+            if ($found === false || empty($followId)) {
+                return false; // No such follow found
+            }
+
+            // Now, delete the row
+            $sql = 'delete from follows where source_user = ? and target_user = ?';
+            $stmt = $dbh->prepare($sql);
+            if ($stmt === false) {
+                throw new \Federator\Exceptions\ServerError('Followers::removeFollow Failed to prepare delete '
+                    . 'statement');
+            }
+            $stmt->bind_param('ss', $sourceUser, $targetUserId);
+            $stmt->execute();
+            $affectedRows = $stmt->affected_rows;
+            $stmt->close();
+
+            return $affectedRows > 0 ? $followId : false;
+        }
+        return false;
+    }
+}

php/federator/dio/posts.php

@@ -13,47 +13,331 @@ namespace Federator\DIO;
  */
 class Posts
 {
-
     /**
      * get posts by user
      *
      * @param \mysqli $dbh @unused-param
      *          database handle
-     * @param string $id
+     * @param string $userid
      *          user id
      * @param \Federator\Connector\Connector $connector
      *          connector to fetch use with
      * @param \Federator\Cache\Cache|null $cache
      *          optional caching service
-     * @param string $minId
-     *          minimum ID
-     * @param string $maxId
-     *          maximum ID
-     * @return \Federator\Data\ActivityPub\Common\APObject[]
+     * @param int $min
+     *          minimum timestamp
+     * @param int $max
+     *          maximum timestamp
+     * @param int $limit
+     *          maximum number of results
+     * @return \Federator\Data\ActivityPub\Common\Activity[]
      */
-    public static function getPostsByUser($dbh, $id, $connector, $cache, $minId, $maxId)
+    public static function getPostsByUser($dbh, $userid, $connector, $cache, $min, $max, $limit)
     {
         // ask cache
         if ($cache !== null) {
-            $posts = $cache->getRemotePostsByUser($id, $minId, $maxId);
+            $posts = $cache->getRemotePostsByUser($userid, $min, $max, $limit);
             if ($posts !== false) {
                 return $posts;
             }
         }
-        $posts = [];
-        // TODO: check our db
+        $posts = self::getPostsFromDb($dbh, $userid, $min, $max, $limit);
+        if ($posts === false) {
+            $posts = [];
+        }
 
-        if ($posts === []) {
-            // ask connector for user-id
-            $posts = $connector->getRemotePostsByUser($id, $minId, $maxId);
-            if ($posts === false) {
-                $posts = [];
+        // Only override $min if we found posts in our DB
+        $remoteMin = $min;
+        if (!empty($posts)) {
+            // Find the latest published date in the DB posts
+            $latestPublished = null;
+            foreach ($posts as $post) {
+                $published = $post->getPublished();
+                if ($published != null) {
+                    if ($latestPublished === null || $published > $latestPublished) {
+                        $latestPublished = $published;
+                    }
+                }
+            }
+            if ($latestPublished !== null) {
+                $remoteMin = $latestPublished;
             }
         }
-        // save posts to DB
+
+        // Fetch newer posts from connector (if any) if max is not set and limit not reached
+        if ($max == 0 && sizeof($posts) < $limit) {
+            $newPosts = $connector->getRemotePostsByUser($userid, $remoteMin, $max, $limit);
+            if ($newPosts !== false && is_array($newPosts)) {
+                // Merge new posts with DB posts, avoiding duplicates by ID
+                $existingIds = [];
+                foreach ($posts as $post) {
+                    $existingIds[$post->getID()] = true;
+                }
+                foreach ($newPosts as $newPost) {
+                    if (!isset($existingIds[$newPost->getID()])) {
+                        if ($newPost->getID() !== '') {
+                            self::savePost($dbh, $userid, $newPost);
+                        }
+                        if (sizeof($posts) < $limit) {
+                            $posts[] = $newPost;
+                        }
+                    }
+                }
+            }
+        }
+
+        $originUrl = 'localhost';
+        if (isset($_SERVER['HTTP_HOST'])) {
+            $originUrl = $_SERVER['HTTP_HOST']; // origin of our request - e.g. mastodon
+        } elseif (isset($_SERVER['HTTP_ORIGIN'])) {
+            $origin = $_SERVER['HTTP_ORIGIN'];
+            $parsed = parse_url($origin);
+            if (isset($parsed) && isset($parsed['host'])) {
+                $parsedHost = $parsed['host'];
+                if (is_string($parsedHost) && $parsedHost !== '') {
+                    $originUrl = $parsedHost;
+                }
+            }
+        }
+        if (!isset($originUrl) || $originUrl === '') {
+            $originUrl = 'localhost'; // Fallback to localhost if no origin is set
+        }
+
+        // optionally convert from article to note
+        foreach ($posts as $post) {
+            switch (strtolower($post->getType())) {
+                case 'undo':
+                    $object = $post->getObject();
+                    if (is_object($object)) {
+                        if (strtolower($object->getType()) === 'article') {
+                            if ($object instanceof \Federator\Data\ActivityPub\Common\Article) {
+                                $object = \Federator\DIO\Article::conditionalConvertToNote($object, $originUrl);
+                                $post->setObject($object);
+                            }
+                        }
+                    }
+
+                    break;
+
+                case 'create':
+                case 'update':
+                    $object = $post->getObject();
+                    if (is_object($object)) {
+                        if (strtolower($object->getType()) === 'article') {
+                            if ($object instanceof \Federator\Data\ActivityPub\Common\Article) {
+                                $object = \Federator\DIO\Article::conditionalConvertToNote($object, $originUrl);
+                                $post->setObject($object);
+                            }
+                        }
+                    }
+
+                    break;
+
+                default:
+                    break;
+            }
+        }
+
         if ($cache !== null) {
-            $cache->saveRemotePostsByUser($id, $posts);
+            $cache->saveRemotePostsByUser($userid, $min, $max, $limit, $posts);
         }
         return $posts;
     }
+
+    /**
+     * Get posts for a user from the DB (optionally by date)
+     *
+     * @param \mysqli $dbh
+     * @param string $userId
+     * @param int $min min timestamp
+     * @param int $max max timestamp
+     * @param int $limit
+     * @return \Federator\Data\ActivityPub\Common\Activity[]|false
+     */
+    public static function getPostsFromDb($dbh, $userId, $min, $max, $limit = 20)
+    {
+        $sql = 'SELECT `id`, `url`, `user_id`, `actor`, `type`, `object`, `to`, `cc`, unix_timestamp(`published`) as '
+            . 'published FROM posts WHERE user_id = ?';
+        $params = [$userId];
+        $types = 's';
+        if ($min > 0) {
+            $sql .= ' AND published >= from_unixtime(?)';
+            $params[] = $min;
+            $types .= 's';
+        }
+        if ($max > 0) {
+            $sql .= ' AND published <= from_unixtime(?)';
+            $params[] = $max;
+            $types .= 's';
+        }
+        $sql .= ' ORDER BY published DESC LIMIT ' . $limit;
+
+        $stmt = $dbh->prepare($sql);
+        if ($stmt === false) {
+            throw new \Federator\Exceptions\ServerError();
+        }
+        $stmt->bind_param($types, ...$params);
+        $stmt->execute();
+        $result = $stmt->get_result();
+        if (!($result instanceof \mysqli_result)) {
+            $stmt->close();
+            return false;
+        }
+        $posts = [];
+        while ($row = $result->fetch_assoc()) {
+            if (isset($row['to']) && $row['to'] !== null) {
+                $row['to'] = json_decode($row['to'], true);
+            }
+            if (isset($row['cc']) && $row['cc'] !== null) {
+                $row['cc'] = json_decode($row['cc'], true);
+            }
+            if (isset($row['object']) && $row['object'] !== null) {
+                $decoded = json_decode($row['object'], true);
+                // Only use decoded value if it's an array/object
+                if (is_array($decoded)) {
+                    $row['object'] = $decoded;
+                }
+            }
+            if (isset($row['published']) && $row['published'] !== null) {
+                // If it's numeric, keep as int. If it's a string, try to parse as ISO 8601.
+                if (!is_numeric($row['published'])) {
+                    // Try to parse as datetime string
+                    $timestamp = strtotime($row['published']);
+                    $row['published'] = $timestamp !== false ? $timestamp : null;
+                }
+            }
+            $activity = \Federator\Data\ActivityPub\Factory::newActivityFromJson($row);
+            if ($activity !== false) {
+                $posts[] = $activity;
+            }
+        }
+        $stmt->close();
+        return $posts;
+    }
+
+    /**
+     * Save a post (insert or update)
+     *
+     * @param \mysqli $dbh
+     * @param string $userId
+     * @param \Federator\Data\ActivityPub\Common\Activity $post
+     * @param string|null $articleId the original id of the article
+     *                           (used to identify the source article in the remote system)
+     * @return bool
+     */
+    public static function savePost($dbh, $userId, $post, $articleId = null)
+    {
+        $sql = 'INSERT INTO posts (
+                `id`, `url`, `user_id`, `actor`, `type`, `object`, `to`, `cc`, `published`, `article_id`
+            ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+            ON DUPLICATE KEY UPDATE
+                `url` = VALUES(`url`),
+                `user_id` = VALUES(`user_id`),
+                `actor` = VALUES(`actor`),
+                `type` = VALUES(`type`),
+                `object` = VALUES(`object`),
+                `to` = VALUES(`to`),
+                `cc` = VALUES(`cc`),
+                `published` = VALUES(`published`),
+                `article_id` = VALUES(`article_id`)';
+        $stmt = $dbh->prepare($sql);
+        if ($stmt === false) {
+            throw new \Federator\Exceptions\ServerError();
+        }
+
+        $id = $post->getID();
+        $url = $post->getUrl();
+        $actor = $post->getAActor();
+        $type = $post->getType();
+        $object = $post->getObject();
+        $objectJson = ($object instanceof \Federator\Data\ActivityPub\Common\APObject)
+            ? json_encode($object)
+            : $object;
+        if ($objectJson === false) {
+            $objectJson = null;
+        }
+        if (is_object($object)) {
+            $id = $object->getID();
+        }
+        $to = $post->getTo();
+        $cc = $post->getCC();
+        $toJson = is_array($to) ? json_encode($to) : (is_string($to) ? json_encode([$to]) : null);
+        $ccJson = is_array($cc) ? json_encode($cc) : (is_string($cc) ? json_encode([$cc]) : null);
+        $published = $post->getPublished();
+        $publishedStr = $published ? gmdate('Y-m-d H:i:s', $published) : gmdate('Y-m-d H:i:s');
+
+        $stmt->bind_param(
+            'ssssssssss',
+            $id,
+            $url,
+            $userId,
+            $actor,
+            $type,
+            $objectJson,
+            $toJson,
+            $ccJson,
+            $publishedStr,
+            $articleId,
+        );
+        $result = $stmt->execute();
+        $stmt->close();
+        return $result;
+    }
+
+    /**
+     * Delete a post
+     *
+     * @param \mysqli $dbh
+     * @param string $id   The post ID
+     * @return bool
+     */
+    public static function deletePost($dbh, $id)
+    {
+        $sql = 'delete from posts where id = ?';
+        $stmt = $dbh->prepare($sql);
+        if ($stmt === false) {
+            throw new \Federator\Exceptions\ServerError();
+        }
+        $stmt->bind_param('s', $id);
+        $stmt->execute();
+        $affectedRows = $stmt->affected_rows;
+        $stmt->close();
+        return $affectedRows > 0;
+    }
+
+    /** retrieve original article id of post
+     *
+     * @param \mysqli $dbh
+     * @param \Federator\Data\ActivityPub\Common\Activity $post
+     * @return string|null
+     */
+    public static function getOriginalArticleId($dbh, $post)
+    {
+        $sql = 'SELECT `article_id` FROM posts WHERE id = ?';
+        $stmt = $dbh->prepare($sql);
+        if ($stmt === false) {
+            throw new \Federator\Exceptions\ServerError();
+        }
+        $id = $post->getID();
+        $object = $post->getObject();
+        if (is_object($object)) {
+            $inReplyTo = $object->getInReplyTo();
+            if ($inReplyTo !== '') {
+                $id = $inReplyTo; // Use inReplyTo as ID if it's a string
+            } else {
+                $id = $object->getObject();
+            }
+        } elseif (is_string($object)) {
+            $id = $object; // If object is a string, use it directly
+        }
+        $stmt->bind_param('s', $id);
+        $articleId = null;
+        $ret = $stmt->bind_result($articleId);
+        $stmt->execute();
+        if ($ret) {
+            $stmt->fetch();
+        }
+        $stmt->close();
+        return $articleId;
+    }
 }

php/federator/dio/server.php

@@ -0,0 +1,108 @@
+<?php
+/**
+ * SPDX-FileCopyrightText: 2025 Sascha Nitsch (grumpydeveloper) https://contentnation.net/@grumpydevelop
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ *
+ * @author Sascha Nitsch (grumpyveveloper)
+ **/
+
+namespace Federator\DIO;
+
+/**
+ * Do the Server2Server communication
+ */
+class Server
+{
+    /**
+     * send activity to federated server
+     *
+     * @param \mysqli $dbh database handle
+     * @param string $ourhost host url of our server (e.g. federator)
+     * @param \Federator\Data\User $sender source user
+     * @param \Federator\Data\FedUser $receiver federated user to receive the activity
+     * @param \Federator\Data\ActivityPub\Common\Activity $activity activity to send
+     * @return boolean true on success
+     */
+    public static function sendActivity($dbh, $ourhost, $sender, $receiver, $activity)
+    {
+        $receiverInboxUrl = $receiver->inboxURL;
+
+        $json = json_encode($activity, JSON_UNESCAPED_SLASHES);
+
+        if ($json === false) {
+            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';
+        echo "inboxurl $receiverInboxUrl\n";
+        $parsedReceiverInboxUrl = parse_url($receiverInboxUrl);
+        if ($parsedReceiverInboxUrl === false) {
+            throw new \Exception('Failed to parse URL: ' . $receiverInboxUrl);
+        }
+
+        if (!isset($parsedReceiverInboxUrl['host']) || !isset($parsedReceiverInboxUrl['path'])) {
+            throw new \Exception('Invalid inbox URL: missing host or path');
+        }
+        $extHost = $parsedReceiverInboxUrl['host'];
+        $path = $parsedReceiverInboxUrl['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, $sender->id); // OR from DB
+        if ($privateKey === false) {
+            throw new \Exception('Failed to get private key');
+        }
+        $pkeyId = openssl_pkey_get_private($privateKey);
+
+        if ($pkeyId === false) {
+            throw new \Exception('Invalid private key');
+        }
+echo "signaturestring $signatureString\n";
+        openssl_sign($signatureString, $signature, $pkeyId, OPENSSL_ALGO_SHA256);
+        $signature_b64 = base64_encode($signature);
+
+        // Build keyId (public key ID from your actor object)
+        $keyId = $ourhost . '/' . $sender->id . '#main-key';
+
+        $signatureHeader = 'keyId="' . $keyId
+            . '",algorithm="rsa-sha256",headers="(request-target) host date digest",signature="' . $signature_b64 . '"';
+
+        $ch = curl_init($receiverInboxUrl);
+        if ($ch === false) {
+            throw new \Exception('Failed to initialize cURL');
+        }
+        $headers = [
+            'Host: ' . $extHost,
+            'Date: ' . $date,
+            'Digest: ' . $digest,
+            'Content-Type: application/activity+json',
+            'Signature: ' . $signatureHeader,
+            'Accept: application/activity+json',
+        ];
+print_r($headers);
+        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($ch);
+
+        if ($response === false) {
+            throw new \Exception('Failed to send activity: ' . curl_error($ch));
+        } else {
+            $httpcode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
+            if ($httpcode != 200 && $httpcode != 202) {
+                throw new \Exception('Unexpected HTTP code ' . $httpcode . ':' . $response);
+            }
+        }
+        if ($response !== true) {
+            error_log($response);
+        }
+        return true;
+    }
+}

php/federator/dio/user.php

@@ -26,9 +26,9 @@ class User
         $sql = 'select unix_timestamp(`validuntil`) from users where id=?';
         $stmt = $dbh->prepare($sql);
         if ($stmt === false) {
-            throw new \Federator\Exceptions\ServerError();
+            throw new \Federator\Exceptions\ServerError('User::addLocalUser Failed to prepare statement');
         }
-        $stmt->bind_param("s", $_user);
+        $stmt->bind_param('s', $_user);
         $validuntil = 0;
         $ret = $stmt->bind_result($validuntil);
         $stmt->execute();
@@ -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,';
@@ -49,11 +50,11 @@ class User
             $sql .= ' values (?, ?, ?, ?, now() + interval 1 day, ?, ?, ?, ?, ?, ?, ?, ?)';
             $stmt = $dbh->prepare($sql);
             if ($stmt === false) {
-                throw new \Federator\Exceptions\ServerError();
+                throw new \Federator\Exceptions\ServerError('User::addLocalUser Failed to prepare create statement');
             }
             $registered = gmdate('Y-m-d H:i:s', $user->registered);
             $stmt->bind_param(
-                "ssssssssssss",
+                'ssssssssssss',
                 $_user,
                 $user->externalid,
                 $public,
@@ -73,11 +74,11 @@ class User
             $sql .= ' iconmediatype=?, iconurl=?, imagemediatype=?, imageurl=? where id=?';
             $stmt = $dbh->prepare($sql);
             if ($stmt === false) {
-                throw new \Federator\Exceptions\ServerError();
+                throw new \Federator\Exceptions\ServerError('User::addLocalUser Failed to prepare update statement');
             }
             $registered = gmdate('Y-m-d H:i:s', $user->registered);
             $stmt->bind_param(
-                "sssssssss",
+                'sssssssss',
                 $user->type,
                 $user->name,
                 $user->summary,
@@ -100,18 +101,42 @@ 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('User::getrsaprivate Failed to prepare statement');
+        }
+        $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);
         if ($stmt === false) {
-            throw new \Federator\Exceptions\ServerError();
+            throw new \Federator\Exceptions\ServerError('User::extendUser Failed to prepare statement');
         }
         $stmt->bind_param("s", $_user);
         $validuntil = 0;
@@ -157,9 +182,9 @@ class User
         $sql .= 'iconmediatype,iconurl,imagemediatype,imageurl from users where id=? and validuntil>=now()';
         $stmt = $dbh->prepare($sql);
         if ($stmt === false) {
-            throw new \Federator\Exceptions\ServerError();
+            throw new \Federator\Exceptions\ServerError('User::getUserByName Failed to prepare statement');
         }
-        $stmt->bind_param("s", $_name);
+        $stmt->bind_param('s', $_name);
         $user = new \Federator\Data\User();
         $ret = $stmt->bind_result(
             $user->id,
@@ -184,12 +209,10 @@ class User
             $ruser = $connector->getRemoteUserByName($_name);
             if ($ruser !== false) {
                 $user = $ruser;
+                self::addLocalUser($dbh, $user, $_name);
             }
         }
         if ($cache !== null) {
-            if ($user->id === null && $user->externalid !== null) {
-                self::addLocalUser($dbh, $user, $_name);
-            }
             $cache->saveRemoteUserByName($_name, $user);
         }
         return $user;

php/federator/dio/votes.php

@@ -0,0 +1,97 @@
+<?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 votes
+ */
+class Votes
+{
+    /**
+     * Add a vote (like/dislike)
+     *
+     * @param \mysqli $dbh
+     * @param string $userId      The user who votes
+     * @param string $targetId    The object being voted on (e.g., post id)
+     * @param string $type        'like' or 'dislike'
+     * @return string|false       The generated vote ID on success, false on failure
+     */
+    public static function addVote($dbh, $userId, $targetId, $type)
+    {
+        // Check if already voted
+        $sql = 'SELECT id FROM votes WHERE user_id = ? AND target_id = ? AND type = ?';
+        $stmt = $dbh->prepare($sql);
+        if ($stmt === false) {
+            throw new \Federator\Exceptions\ServerError();
+        }
+        $stmt->bind_param('sss', $userId, $targetId, $type);
+        $foundId = 0;
+        $ret = $stmt->bind_result($foundId);
+        $stmt->execute();
+        if ($ret) {
+            $stmt->fetch();
+        }
+        $stmt->close();
+        if ($foundId != 0) {
+            return false; // Already voted
+        }
+
+        // Generate a unique ID for the vote
+        do {
+            $id = bin2hex(openssl_random_pseudo_bytes(16));
+            // Check if the generated ID is unique
+            $sql = 'SELECT id FROM votes WHERE id = ?';
+            $stmt = $dbh->prepare($sql);
+            if ($stmt === false) {
+                throw new \Federator\Exceptions\ServerError();
+            }
+            $stmt->bind_param('s', $id);
+            $foundId = 0;
+            $ret = $stmt->bind_result($foundId);
+            $stmt->execute();
+            if ($ret) {
+                $stmt->fetch();
+            }
+            $stmt->close();
+        } while ($foundId > 0);
+
+        // Add vote with created_at timestamp
+        $sql = 'INSERT INTO votes (id, user_id, target_id, type, created_at) VALUES (?, ?, ?, ?, NOW())';
+        $stmt = $dbh->prepare($sql);
+        if ($stmt === false) {
+            throw new \Federator\Exceptions\ServerError();
+        }
+        $stmt->bind_param('ssss', $id, $userId, $targetId, $type);
+        $stmt->execute();
+        $stmt->close();
+        return $id; // Return the generated vote ID
+    }
+
+    /**
+     * Remove a vote (like/dislike)
+     *
+     * @param \mysqli $dbh
+     * @param string $userId
+     * @param string $targetId
+     * @return bool             true on success
+     */
+    public static function removeVote($dbh, $userId, $targetId)
+    {
+        $sql = 'DELETE FROM votes WHERE user_id = ? AND target_id = ?';
+        $stmt = $dbh->prepare($sql);
+        if ($stmt === false) {
+            throw new \Federator\Exceptions\ServerError();
+        }
+        $stmt->bind_param('ss', $userId, $targetId);
+        $stmt->execute();
+        $affectedRows = $stmt->affected_rows;
+        $stmt->close();
+        return $affectedRows > 0;
+    }
+}

php/federator/jobs/inboxjob.php

@@ -0,0 +1,78 @@
+<?php
+
+namespace Federator\Jobs;
+
+class InboxJob extends \Federator\Api
+{
+    /** @var array<string, mixed> $args Arguments for the job */
+    public $args = [];
+
+    /**
+     * cache instance
+     *
+     * @var \Federator\Cache\Cache $cache
+     */
+    protected $cache;
+
+    /**
+     * remote connector
+     *
+     * @var \Federator\Connector\Connector $connector
+     */
+    protected $connector = null;
+
+    /**
+     * database instance
+     *
+     * @var \Mysqli $dbh
+     */
+    protected $dbh;
+
+    /**
+     * constructor
+     */
+    public function __construct()
+    {
+        parent::__construct();
+    }
+
+    /**
+     * Set up environment for this job
+     */
+    public function setUp(): void
+    {
+        $this->openDatabase();
+        $this->loadPlugins();
+    }
+
+    /**
+     * Perform the inbox job.
+     *
+     * @return bool true on success, false on failure
+     */
+    public function perform(): bool
+    {
+        error_log('InboxJob: Starting job');
+        $user = $this->args['user'];
+        $recipientId = $this->args['recipientId'];
+        $activity = $this->args['activity'];
+
+        $inboxActivity = \Federator\Data\ActivityPub\Factory::newActivityFromJson($activity);
+
+        if ($inboxActivity === false) {
+            error_log('InboxJob: Failed to create inboxActivity from JSON');
+            return false;
+        }
+
+        \Federator\DIO\FedUser::inboxForUser(
+            $this,
+            $this->dbh,
+            $this->connector,
+            $this->cache,
+            $user,
+            $recipientId,
+            $inboxActivity
+        );
+        return true;
+    }
+}

php/federator/jobs/newcontentjob.php

@@ -0,0 +1,83 @@
+<?php
+
+namespace Federator\Jobs;
+
+class NewContentJob extends \Federator\Api
+{
+    /** @var array<string, mixed> $args Arguments for the job */
+    public $args = [];
+
+    /**
+     * cache instance
+     *
+     * @var \Federator\Cache\Cache $cache
+     */
+    protected $cache;
+
+    /**
+     * remote connector
+     *
+     * @var \Federator\Connector\Connector $connector
+     */
+    protected $connector = null;
+
+    /**
+     * database instance
+     *
+     * @var \Mysqli $dbh
+     */
+    protected $dbh;
+
+    /**
+     * constructor
+     */
+    public function __construct()
+    {
+        parent::__construct();
+    }
+
+    /**
+     * Set up environment for this job
+     */
+    public function setUp(): void
+    {
+        $this->openDatabase();
+        $this->loadPlugins();
+    }
+
+    /**
+     * Perform the inbox job.
+     *
+     * @return bool true on success, false on failure
+     */
+    public function perform(): bool
+    {
+        error_log('NewContentJob: Starting job');
+        $user = $this->args['user'];
+        $recipientId = $this->args['recipientId'];
+        $activity = $this->args['activity'];
+        $articleId = $this->args['articleId'] ?? null;
+
+        $activity = \Federator\Data\ActivityPub\Factory::newActivityFromJson($activity);
+
+        if ($activity === false) {
+            error_log('NewContentJob: Failed to create activity from JSON');
+            return false;
+        }
+        $domain = $this->config['generic']['externaldomain'];
+
+        $ourUrl = 'https://' . $domain;
+
+        \Federator\Api\V1\NewContent::postForUser(
+            $this->dbh,
+            $this->connector,
+            $this->cache,
+            $ourUrl,
+            $user,
+            $recipientId,
+            $activity,
+            $articleId
+        );
+        return true;
+    }
+}

php/federator/language.php

@@ -20,9 +20,9 @@ class Language
      * @var array $validLanguages
      */
     private $validLanguages = array(
-        "de" => true,
-        "en" => true,
-        "xy" => true
+        'de' => true,
+        'en' => true,
+        'xy' => true
     );
 
     /**
@@ -96,8 +96,8 @@ class Language
             if ($root === '') {
                 $root = '.';
             }
-            if (@file_exists($root . '../lang/federator/' . $this->uselang . "/$group.inc")) {
-                require($root . '../lang/federator/' . $this->uselang . "/$group.inc");
+            if (@file_exists($root . '../lang/federator/' . $this->uselang . '/' . $group . '.inc')) {
+                require($root . '../lang/federator/' . $this->uselang . '/' . $group . '.inc');
                 $this->lang[$group] = $l;
             }
         }
@@ -107,15 +107,15 @@ class Language
                 if (isset($values[$i])) {
                     $string = str_replace("\$$i", $values[$i], $string);
                 } else {
-                    $string = str_replace("\$$i", "", $string);
+                    $string = str_replace("\$$i", '', $string);
                 }
             }
             return $string;
         }
         $basedir = $_SERVER['DOCUMENT_ROOT'] . '/../';
-        $fh = @fopen("$basedir/logs/missingtrans.txt", 'a');
+        $fh = @fopen($basedir . '/logs/missingtrans.txt', 'a');
         if ($fh !== false) {
-            fwrite($fh, $this->uselang.":$group:$key\n");
+            fwrite($fh, $this->uselang . ':' . $group . ':' . "$key\n");
             fclose($fh);
         }
         return ">>$group:$key<<";
@@ -132,7 +132,7 @@ class Language
     {
         if (! isset($this->lang[$group])) {
             $l = [];
-            require_once($_SERVER['DOCUMENT_ROOT'] . '/../lang/' . $this->uselang . "/$group.inc");
+            require_once($_SERVER['DOCUMENT_ROOT'] . '/../lang/' . $this->uselang . '/' . $group . '.inc');
             $this->lang[$group] = $l;
         }
         // @phan-suppress-next-line PhanPartialTypeMismatchReturn
@@ -288,7 +288,7 @@ function smarty_function_printlang($params, $template) : string
  */
 function smarty_function_printjslang($params, $template) : string
 {
-    $lang = $template->getTemplateVars("language");
+    $lang = $template->getTemplateVars('language');
     $prefix = 'window.translations.' . $params['group'] . '.' . $params['key'] . ' = \'';
     $postfix = '\';';
     if (isset($params['var'])) {

php/federator/main.php

@@ -20,31 +20,43 @@ class Main
      *
      * @var Cache\Cache $cache
      */
-    protected $cache;
+    protected $cache = null;
+
     /**
      * current config
      *
      * @var array<string,mixed>  $config
      */
     protected $config;
+
     /**
      * remote connector
      *
      * @var Connector\Connector $connector
      */
     protected $connector = null;
+
+    /**
+     * remote host (f.e. https://contentnation.net)
+     *
+     * @var string $host
+     */
+    protected $host = null;
+
     /**
      * response content type
      *
      * @var string $contentType
      */
-    protected $contentType = "text/html";
+    protected $contentType = 'text/html';
+
     /**
      * database instance
      *
      * @var \Mysqli $dbh
      */
     protected $dbh;
+
     /**
      * extra headers
      *
@@ -150,9 +162,19 @@ class Main
         return $this->connector;
     }
 
+    /**
+     * get host (f.e. https://contentnation.net)
+     *
+     * @return string
+     */
+    public function getHost()
+    {
+        return $this->host;
+    }
+
     /**
      * get config
-     * @return Array<String, Mixed>
+     * @return array<string, mixed>
      */
     public function getConfig()
     {
@@ -172,7 +194,7 @@ class Main
     /**
      * load plugins
      */
-    public function loadPlugins() : void
+    public function loadPlugins(): void
     {
         if (array_key_exists('plugins', $this->config)) {
             $basepath = $_SERVER['DOCUMENT_ROOT'] . '../plugins/federator/';
@@ -196,11 +218,11 @@ class Main
      */
     public function openDatabase($usernameOverride = null, $passwordOverride = null)
     {
-        $dbconf = $this->config["database"];
+        $dbconf = $this->config['database'];
         $this->dbh = new \mysqli(
             $dbconf['host'],
-            $usernameOverride ?? (string)$dbconf['username'],
-            $passwordOverride ?? (string)$dbconf['password'],
+            $usernameOverride ?? (string) $dbconf['username'],
+            $passwordOverride ?? (string) $dbconf['password'],
             $dbconf['database']
         );
         if ($this->dbh->connect_error !== null) {
@@ -232,27 +254,51 @@ class Main
 
     /**
      * set cache
+     *
+     * @param \Federator\Cache\Cache $cache the new cache
      */
-    public function setCache(Cache\Cache $cache) : void
+    public function setCache(Cache\Cache $cache): void
     {
         $this->cache = $cache;
     }
 
     /**
      * set connector
+     *
+     * @param \Federator\Connector\Connector $connector the new connector
      */
     public function setConnector(Connector\Connector $connector) : void
     {
         $this->connector = $connector;
     }
 
+    /**
+     * set host
+     *
+     * @param string $host the new host url
+     */
+    public function setHost(string $host) : void
+    {
+        $this->host = $host;
+    }
+
+    /**
+     * set content type
+     *
+     * @param string $_type content type
+     */
+    public function setContentType($_type): void
+    {
+        $this->contentType = $_type;
+    }
+
     /**
      * set response code
      *
      * @param int $code
      *          new response code
      */
-    public function setResponseCode(int $code) : void
+    public function setResponseCode(int $code): void
     {
         $this->responseCode = $code;
     }
@@ -270,7 +316,7 @@ class Main
      *          optional parameters
      * @return string translation
      */
-    public static function translate(?string $lang, string $group, string $key, array $parameters = array()) : string
+    public static function translate(?string $lang, string $group, string $key, array $parameters = array()): string
     {
         $l = new Language($lang);
         return $l->printlang($group, $key, $parameters);
@@ -281,7 +327,7 @@ class Main
      *
      * @param ?string $lang
      */
-    public static function validLanguage(?string $lang) : bool
+    public static function validLanguage(?string $lang): bool
     {
         $language = new Language($lang);
         if ($language->getLang() === $lang) {

php/federator/maintenance.php

@@ -22,7 +22,7 @@ class Maintenance
      */
     public static function run($argc, $argv)
     {
-        date_default_timezone_set("Europe/Berlin");
+        date_default_timezone_set('Europe/Berlin');
         spl_autoload_register(static function (string $className) {
             $root = $_SERVER['DOCUMENT_ROOT'];
             include $root . '../php/' . str_replace("\\", "/", strtolower($className)) . '.php';

php/federator/test.php

@@ -0,0 +1,200 @@
+<?php
+/**
+ * SPDX-FileCopyrightText: 2024 Sascha Nitsch (grumpydeveloper) https://contentnation.net/@grumpydevelop
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ *
+ * @author Sascha Nitsch (grumpydeveloper)
+ **/
+
+namespace Federator;
+
+/**
+ * test functions
+ */
+class Test
+{
+    /**
+     * fetch outbox
+     * @param string $_name user handle to fetch
+     * @return void
+     */
+    public static function fetchOutbox($_name)
+    {
+        // make webfinger request
+        $r = self::webfinger($_name);
+        $outbox = $r['outbox'];
+        $headers = ['Accept: application/activity+json'];
+        [$response, $info] = \Federator\Main::getFromRemote($outbox, $headers);
+        if ($info['http_code'] != 200) {
+            return;
+        }
+        $json = json_decode($response, true);
+        if ($json === false) {
+            return;
+        }
+        $ap = \Federator\Data\ActivityPub\Factory::newFromJson($json, $response);
+        if (!($ap instanceof \Federator\Data\ActivityPub\Common\OrderedCollection)) {
+            echo "unsupport reply from $outbox\n";
+            return;
+        }
+        // first and total items should be set
+        $total = $ap->getTotalItems();
+        echo "total items: " . $total;
+        echo " first: " . $ap->getFirst() . "\n";
+
+        $page = $ap->getFirst();
+        $count = 0;
+
+        while ($count < $total) {
+            echo "query $page\n";
+            // query pages
+            [$response, $info] = \Federator\Main::getFromRemote($page, $headers);
+            if ($info['http_code'] != 200) {
+                return;
+            }
+            // echo "'$response'\n";
+            $json = json_decode($response, true);
+            $ap = \Federator\Data\ActivityPub\Factory::newFromJson($json, $response);
+            if (!($ap instanceof \Federator\Data\ActivityPub\Common\OrderedCollectionPage)) {
+                echo "unsupport reply from $page\n";
+                return;
+            }
+            $thisCount = $ap->getCount();
+            echo "count: " . $thisCount . "\n";
+            for ($i = 0; $i < $thisCount; ++$i) {
+                $entry = $ap->get($i);
+                if ($entry instanceof \Federator\Data\ActivityPub\Common\APObject) {
+                    echo $entry->getID() . " " . $entry->getPublished() . "\n";
+                }
+            }
+            $count += $thisCount;
+            $page = $ap->getNext();
+        }
+        //print_r($ap);
+    }
+    /**
+     * run test
+     *
+     * @param int $argc number of arguments
+     * @param string[] $argv arguments
+     * @return void
+     */
+    public static function run($argc, $argv)
+    {
+        date_default_timezone_set('Europe/Berlin');
+        spl_autoload_register(static function (string $className) {
+            include PROJECT_ROOT . '/php/' . str_replace("\\", "/", strtolower($className)) . '.php';
+        });
+        if ($argc < 2) {
+            self::printUsage();
+        }
+        // pretend that we are running from web directory
+        define('PROJECT_ROOT', dirname(__DIR__, 2));
+        $api = new \Federator\Api();
+        $api->loadPlugins();
+        $api->openDatabase();
+
+        for ($i = 1; $i < $argc; ++$i) {
+            switch ($argv[$i]) {
+                case 'fetchoutbox':
+                    self::fetchOutbox($argv[$i + 1]);
+                    ++$i;
+                    break;
+                case 'upvote':
+                    self::upvote($api, $argv[$i + 1]);
+                    ++$i;
+                    break;
+                default:
+                    self::printUsage();
+            }
+        }
+    }
+
+
+    /**
+     * print usage of test tool
+     *
+     * @return void
+     */
+    public static function printUsage()
+    {
+        echo "usage php test.php <command> <parameter> [<command> <parameter>...]\n";
+        echo "command can be one of:\n";
+        echo " fetchoutbox - fetch users outbox. parameter: username\n";
+        echo " upvote - upvote. parameter: URL to upvote\n";
+        echo " downvote - downvote. parameter: URL to downvote\n";
+        echo " comment - comment. parameter: URL to comment, text to comment\n";
+        echo " Run this after you updated the program files\n";
+        exit();
+    }
+
+    /**
+     * upvote given URL
+     *
+     * @param \Federator\Api $api api instance
+     * @param string $_url URL to upvote
+     * @note uses hardcoded source
+     * @return void
+     */
+    public static function upvote($api, $_url)
+    {
+        $dbh = $api->getDatabase();
+        $inboxActivity = new \Federator\Data\ActivityPub\Common\Like();
+        $inboxActivity->setAActor('https://mastodon.local/users/admin');
+        $inboxActivity->setObject($_url);
+        $inboxActivity->setID("https://mastodon.local/users/admin#like/" . md5($_url));
+        \Federator\DIO\FedUser::inboxForUser(
+            $api,
+            $dbh,
+            $api->getConnector(),
+            null,
+            'admin@mastodon.local',
+            "grumpydevelop@192.168.178.143",
+            $inboxActivity
+        );
+    }
+
+    /**
+     * do a webfinger request
+     * @param string $_name name to query
+     */
+    private static function webfinger($_name): mixed
+    {
+        // make webfinger request
+        if (preg_match("/^([^@]+)@(.*)$/", $_name, $matches) != 1) {
+            echo "username is malformed";
+            return false;
+        }
+        $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) {
+            return false;
+        }
+        $r = json_decode($response, true);
+        if (isset($r['links'])) {
+            foreach ($r['links'] as $link) {
+                if (isset($link['rel']) && $link['rel'] === 'self') {
+                    $remoteURL = $link['href'];
+                    break;
+                }
+            }
+        }
+        if (!isset($remoteURL)) {
+            echo "FedUser::getUserByName Failed to find self link in webfinger for " . $_name . "\n";
+            return false;
+        }
+        // fetch the user
+        $headers = ['Accept: application/activity+json'];
+        [$response, $info] = \Federator\Main::getFromRemote($remoteURL, $headers);
+        if ($info['http_code'] != 200) {
+            echo "FedUser::getUserByName Failed to fetch user from remoteUrl for " . $_name . "\n";
+            return false;
+        }
+        $r = json_decode($response, true);
+        return $r;
+    }
+}
+
+
+Test::run($argc, $argv);

php/federator/workers/worker_inbox.php

@@ -0,0 +1,27 @@
+<?php
+
+define('PROJECT_ROOT', dirname(__DIR__, 3));
+require_once PROJECT_ROOT . '/vendor/autoload.php';
+$_SERVER['DOCUMENT_ROOT'] = PROJECT_ROOT . '/htdocs/';
+
+spl_autoload_register(static function (string $className) {
+    include PROJECT_ROOT . '/php/' . str_replace("\\", "/", strtolower($className)) . '.php';
+});
+
+$config = parse_ini_file(PROJECT_ROOT . '/rediscache.ini');
+
+// Set the Redis backend for Resque
+$redisUrl = sprintf(
+    'redis://%s:%s@%s:%d?password-encoding=u',
+    urlencode($config['username']),
+    urlencode($config['password']),
+    $config['host'],
+    intval($config['port'], 10)
+);
+\Resque::setBackend($redisUrl);
+
+// Start the worker
+$worker = new \Resque_Worker(['inbox']);
+
+fwrite(STDOUT, "*** Starting worker for inbox queue\n");
+$worker->work(10); // 10 seconds interval

plugins/federator/dummyconnector.php

@@ -19,15 +19,38 @@ class DummyConnector implements Connector
     {
     }
 
+    /**
+     * get followers of given user
+     *
+     * @param string $userId user id @unused-param
+     * @return \Federator\Data\FedUser[]|false
+     */
+    public function getFollowersByUser($userId)
+    {
+        return false;
+    }
+
+    /**
+     * get following of given user
+     *
+     * @param string $id user id @unused-param
+     * @return \Federator\Data\FedUser[]|false
+     */
+    public function getFollowingByUser($id)
+    {
+        return false;
+    }
+
     /**
      * get posts by given user
      *
      * @param string $id user id @unused-param
-     * @param string $minId min ID @unused-param
-     * @param string $maxId max ID @unused-param
-     * @return \Federator\Data\ActivityPub\Common\APObject[]|false
+     * @param int $min min timestamp @unused-param
+     * @param int $max max timestamp @unused-param
+     * @param int $limit limit number of results @unused-param
+     * @return \Federator\Data\ActivityPub\Common\Activity[]|false
      */
-    public function getRemotePostsByUser($id, $minId, $maxId)
+    public function getRemotePostsByUser($id, $min, $max, $limit)
     {
         return false;
     }
@@ -46,6 +69,19 @@ class DummyConnector implements Connector
         return $stats;
     }
 
+    /**
+     * Convert jsonData to Activity format
+     *
+     * @param array<string, mixed> $jsonData the json data from our platfrom @unused-param
+     * @param string $articleId the original id of the article (if applicable)
+     *                           (used to identify the article in the remote system) @unused-param
+     * @return \Federator\Data\ActivityPub\Common\Activity|false
+     */
+    public function jsonToActivity(array $jsonData, &$articleId)
+    {
+        return false;
+    }
+
     /**
      * get remote user by name
      * @param string $_name user or profile name
@@ -70,10 +106,34 @@ class DummyConnector implements Connector
         // validate $_session and $user
         $user = new \Federator\Data\User();
         $user->externalid = $_user;
-        $user->permissions = ['PUBLISH'];
+        $user->permissions = ['publish'];
         $user->session = $_session;
         return $user;
     }
+
+    /**
+     * send target-friendly json from ActivityPub activity
+     *
+     * @param \Federator\Data\FedUser $sender the user of the sender @unused-param
+     * @param \Federator\Data\ActivityPub\Common\Activity $activity the activity @unused-param
+     * @return boolean did we successfully send the activity?
+     */
+    public function sendActivity($sender, $activity)
+    {
+        return false;
+    }
+
+    /**
+     * check if the headers include a valid signature
+     *
+     * @param string[] $headers the headers @unused-param
+     * @throws \Federator\Exceptions\PermissionDenied
+     * @return string|\Federator\Exceptions\PermissionDenied
+     */
+    public function checkSignature($headers)
+    {
+        return new \Federator\Exceptions\PermissionDenied("Dummy connector: no signature check");
+    }
 }
 
 namespace Federator;

plugins/federator/rediscache.php

@@ -41,6 +41,13 @@ class RedisCache implements Cache
      */
     private $userTTL;
 
+    /**
+     * public key cache time to live in secods
+     *
+     * @var int $publicKeyPemTTL
+     */
+    private $publicKeyPemTTL;
+
     /**
      * constructor
      */
@@ -50,6 +57,8 @@ class RedisCache implements Cache
         if ($config !== false) {
             $this->config = $config;
             $this->userTTL = array_key_exists('userttl', $config) ? intval($config['userttl'], 10) : 60;
+            $this->publicKeyPemTTL = array_key_exists('publickeypemttl', $config)
+              ? intval($config['publickeypemttl'], 10) : 3600;
         }
     }
 
@@ -59,10 +68,20 @@ class RedisCache implements Cache
      */
     private function connect()
     {
-         $this->redis = new \Redis();
-         $this->redis->pconnect($this->config['host'], intval($this->config['port'], 10));
-         // @phan-suppress-next-line PhanTypeMismatchArgumentInternalProbablyReal
-         $this->redis->auth([$this->config['username'], $this->config['password']]);
+        $this->redis = new \Redis();
+        $this->redis->pconnect($this->config['host'], intval($this->config['port'], 10));
+        // @phan-suppress-next-line PhanTypeMismatchArgumentInternalProbablyReal
+        $this->redis->auth([$this->config['username'], $this->config['password']]);
+
+        // Set the Redis backend for Resque
+        $redisUrl = sprintf(
+            'redis://%s:%s@%s:%d',
+            urlencode($this->config['username']),
+            urlencode($this->config['password']),
+            $this->config['host'],
+            intval($this->config['port'], 10)
+        );
+        \Resque::setBackend($redisUrl);
     }
 
     /**
@@ -77,16 +96,57 @@ class RedisCache implements Cache
         return $prefix . '_' . md5($input);
     }
 
+    /**
+     * get followers of given user
+     *
+     * @param string $id user id @unused-param
+
+     * @return \Federator\Data\FedUser[]|false
+     */
+    public function getFollowersByUser($id)
+    {
+        error_log("rediscache::getFollowersByUser not implemented");
+        return false;
+    }
+
+    /**
+     * get following of given user
+     *
+     * @param string $id user id @unused-param
+
+     * @return \Federator\Data\FedUser[]|false
+     */
+    public function getFollowingByUser($id)
+    {
+        error_log("rediscache::getFollowingByUser not implemented");
+        return false;
+    }
+
+    /**
+     * Convert jsonData to Activity format
+     *
+     * @param array<string, mixed> $jsonData the json data from our platfrom @unused-param
+     * @param string $articleId the original id of the article (if applicable)
+     *                           (used to identify the article in the remote system) @unused-param
+     * @return \Federator\Data\ActivityPub\Common\Activity|false
+     */
+    public function jsonToActivity(array $jsonData, &$articleId)
+    {
+        error_log("rediscache::jsonToActivity not implemented");
+        return false;
+    }
+
     /**
      * get posts by given user
      *
      * @param string $id user id @unused-param
-     * @param string $minId min ID @unused-param
-     * @param string $maxId max ID @unused-param
+     * @param int $min min timestamp @unused-param
+     * @param int $max max timestamp @unused-param
+     * @param int $limit limit results @unused-param
 
-     * @return \Federator\Data\ActivityPub\Common\APObject[]|false
+     * @return \Federator\Data\ActivityPub\Common\Activity[]|false
      */
-    public function getRemotePostsByUser($id, $minId, $maxId)
+    public function getRemotePostsByUser($id, $min, $max, $limit)
     {
         error_log("rediscache::getRemotePostsByUser not implemented");
         return false;
@@ -131,6 +191,26 @@ 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
      *
@@ -152,14 +232,56 @@ class RedisCache implements Cache
         return $user;
     }
 
+    /**
+     * Retrieve the public key for a given keyId
+     *
+     * @param string $keyId The keyId (e.g., actor URL + #main-key)
+     * @return string|false The cached public key PEM or false if not found
+     */
+    public function getPublicKey(string $keyId)
+    {
+        if (!$this->connected) {
+            $this->connect();
+        }
+        $key = self::createKey('publickey', $keyId);
+        return $this->redis->get($key);
+    }
+
+    /**
+     * save remote followers by user
+     *
+     * @param string $user user name @unused-param
+     * @param \Federator\Data\FedUser[]|false $followers user followers @unused-param
+     * @return void
+     */
+    public function saveFollowersByUser($user, $followers)
+    {
+        error_log("rediscache::saveFollowersByUser not implemented");
+    }
+
+    /**
+     * save remote following for user
+     *
+     * @param string $user user name @unused-param
+     * @param \Federator\Data\FedUser[]|false $following user following @unused-param
+     * @return void
+     */
+    public function saveFollowingByUser($user, $following)
+    {
+        error_log("rediscache::saveFollowingByUser not implemented");
+    }
+
     /**
      * save remote posts by user
      *
      * @param string $user user name @unused-param
+     * @param int $min min timestamp @unused-param
+     * @param int $max max timestamp @unused-param
+     * @param int $limit limit results @unused-param
      * @param \Federator\Data\ActivityPub\Common\APObject[]|false $posts user posts @unused-param
      * @return void
      */
-    public function saveRemotePostsByUser($user, $posts)
+    public function saveRemotePostsByUser($user, $min, $max, $limit, $posts)
     {
         error_log("rediscache::saveRemotePostsByUser not implemented");
     }
@@ -179,6 +301,7 @@ class RedisCache implements Cache
         $serialized = $stats->toJson();
         $this->redis->setEx($key, $this->config['statsttl'], $serialized);
     }
+
     /**
      * save remote user by name
      *
@@ -187,6 +310,23 @@ class RedisCache implements Cache
      * @return void
      */
     public function saveRemoteUserByName($_name, $user)
+    {
+        if (!$this->connected) {
+            $this->connect();
+        }
+        $key = self::createKey('u', $_name);
+        $serialized = $user->toJson();
+        $this->redis->setEx($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();
@@ -205,7 +345,47 @@ class RedisCache implements Cache
     {
         $key = self::createKey('s', $_session . $_user);
         $serialized = $user->toJson();
-        $this->redis->setEx($key, $this->userTTL, $serialized,);
+        $this->redis->setEx($key, $this->userTTL, $serialized);
+    }
+
+    /**
+     * Save the public key for a given keyId
+     *
+     * @param string $keyId The keyId (e.g., actor URL + #main-key)
+     * @param string $publicKeyPem The public key PEM to cache
+     * @return void
+     */
+    public function savePublicKey(string $keyId, string $publicKeyPem)
+    {
+        if (!$this->connected) {
+            $this->connect();
+        }
+        $key = self::createKey('publickey', $keyId);
+        $this->redis->setEx($key, $this->publicKeyPemTTL, $publicKeyPem);
+    }
+
+    /**
+     * send target-friendly json from ActivityPub activity
+     *
+     * @param \Federator\Data\FedUser $sender the user of the sender @unused-param
+     * @param \Federator\Data\ActivityPub\Common\Activity $activity the activity @unused-param
+     * @return boolean did we successfully send the activity?
+     */
+    public function sendActivity($sender, $activity)
+    {
+        return false;
+    }
+
+    /**
+     * check if the headers include a valid signature
+     *
+     * @param string[] $headers the headers @unused-param
+     * @throws \Federator\Exceptions\PermissionDenied
+     * @return string|\Federator\Exceptions\PermissionDenied
+     */
+    public function checkSignature($headers)
+    {
+        return new \Federator\Exceptions\PermissionDenied("RedisCache: no signature check");
     }
 }
 

progress.md

@@ -19,10 +19,10 @@ primary goal is to connect ContentNation via ActivityPub again.
 - [X] full cache for users
 - [X] webfinger
 - [X] discovery endpoints
-- [ ] ap outbox
-- [ ] ap inbox
+- [X] ap outbox
+- [X] ap inbox
 - [ ] support for AP profile in service
 - [ ] support for article
 - [ ] support for comment
 - [ ] posting comments from ap to service
-- [ ] callback from service to add new input
+- [X] callback from service to add new input

rediscache.ini

@@ -4,4 +4,5 @@ port = 6379
 username = federator
 password = redis*change*password
 userttl = 10
+publickeypemttl = 3600
 statsttl = 60

sql/2024-07-24.sql

@@ -0,0 +1,2 @@
+create table outbox (`id` char(32) unique primary key, `user` varchar(255), index(user), `timestamp` timestamp, `type` enum ("article", "note"), index(type), `externalid` varchar(255), index(externalid), `apjson` text);
+update settings set `value`="2024-07-24" where `key`="database_version";

sql/2024-07-30.sql

@@ -0,0 +1,2 @@
+create table webfinger (`subject` varchar(255) unique primary key, `timestamp` timestamp, index(`timestamp`), `aliases` text, `links` text);
+update settings set `value`="2024-07-22" where `key`="database_version";

sql/2024-08-19.sql

@@ -0,0 +1,3 @@
+create table settings(`key` varchar(255) unique primary key, `value` text);
+create table users(`id` varchar(255) unique primary key, `externalid` varchar(255), index(`externalid`), `rsapublic` text, `rsaprivate` text);
+insert into settings (`key`, `value`) value ("database_version", "2024-07-19");

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";

sql/2025-05-19.sql

@@ -0,0 +1,2 @@
+create table posts(`id` varchar(255) primary key,`url` varchar(255) not null,`user_id` varchar(255) not null,`actor` varchar(255) not null,`type` varchar(255) not null default 'note',`object` text default null,`to` text default null,`cc` text default null,`published` timestamp not null default current_timestamp);
+update settings set `value`="2025-05-19" where `key`="database_version";

sql/2025-05-27.sql

@@ -0,0 +1,2 @@
+alter table posts add `article_id` varchar(255) null default null comment 'The optional original article id (of non-federated system, e.g. CN)';
+update settings set `value`="2025-05-27" where `key`="database_version";

templates/federator/host-meta.xml

@@ -1,4 +1,4 @@
-version="1.0" encoding="UTF-8"?>
+<?xml version="1.0" encoding="UTF-8"?>
 <XRD xmlns="http://docs.oasis-open.org/ns/xri/xrd-1.0">
   <Link rel="lrdd" template="https://{$fqdn}/.well-known/webfinger?resource={ldelim}uri{rdelim}"/>
 </XRD>

templates/federator/user.json

@@ -58,32 +58,32 @@
             {rdelim}
         {rdelim}
     ],
-    "id":"https://{$fqdn}/users/{$username}",
+    "id":"https://{$fqdn}/{$username}",
     "type":"{$type}",
-    "following":"https://{$fqdn}/users/{$username}/following",
-    "followers":"https://{$fqdn}/users/{$username}/followers",
-    "inbox":"https://{$fqdn}/users/{$username}/inbox",
-    "outbox":"https://{$fqdn}/users/{$username}/outbox",
-    "featured":"https://{$fqdn}/users/{$username}/collections/featured",
-    "featuredTags":"https://{$fqdn}/users/{$username}/collections/tags",
+    "following":"https://{$fqdn}/{$username}/following",
+    "followers":"https://{$fqdn}/{$username}/followers",
+    "inbox":"https://{$fqdn}/{$username}/inbox",
+    "outbox":"https://{$fqdn}/{$username}/outbox",
+    {*"featured":"https://{$fqdn}/{$username}/collections/featured",
+    "featuredTags":"https://{$fqdn}/{$username}/collections/tags",*}
     "preferredUsername":"{$username}",
     "name":"{$name}",
     "summary":"{$summary}",
-    "url":"https://{$fqdn}/@{$username}",
+    "url":"https://{$sourcedomain}/@{$username}",
     "manuallyApprovesFollowers":false,
     "discoverable":true,
     "published":"{$registered}",
     "publicKey":{ldelim}
-    "id":"https://{$fqdn}/users/{$username}#main-key",
-    "owner":"https://{$fqdn}/users/{$username}",
-    "publicKeyPem":"{$publickey}"
+        "id":"https://{$fqdn}/{$username}#main-key",
+        "owner":"https://{$sourcedomain}/{$username}",
+        "publicKeyPem":"{$publickey}"
     {rdelim},
     "tag":[],
     "attachment":[
         {if $type==='group'}{ldelim}
         "type":"PropertyValue",
         "name":"website",
-        "value":"\u003ca href=\"https://{$fqdn}/@{$username}\" target=\"_blank\" rel=\"nofollow noopener noreferrer me\"\u003e\u003cspan class=\"invisible\"\u003ehttps://\u003c/span\u003e\u003cspan class=\"\"\u003e{$fqdn}/@{$username}\u003c/span\u003e\u003cspan class=\"invisible\"\u003e\u003c/span\u003e\u003c/a\u003e"
+        "value":"\u003ca href=\"https://{$sourcedomain}/@{$username}\" target=\"_blank\" rel=\"nofollow noopener noreferrer me\"\u003e\u003cspan class=\"invisible\"\u003ehttps://\u003c/span\u003e\u003cspan class=\"\"\u003e{$fqdn}/@{$username}\u003c/span\u003e\u003cspan class=\"invisible\"\u003e\u003c/span\u003e\u003c/a\u003e"
         {rdelim}{/if}
     ],
     "endpoints":{ldelim}

templates/federator/webfinger_acct.json

@@ -1,8 +1,7 @@
 {ldelim}
-  "subject": "acct:{$username}@{$domain}",
+  "subject": "acct:{$username}@{$sourcedomain}",
   "aliases": [
-    "https://{$domain}/@{$username}",
-    "https://{$domain}/users/{$username}"
+    "https://{$sourcedomain}/@{$username}"
   ],
   "links": [
     {ldelim}"rel": "self", "type": "application/activity+json", "href": "https://{$domain}/{$username}"{rdelim},