Skell for ActivityPub feed

Add classes description on docblock
Add Delivery Handler (named Postman) and Subscription hook
2018-07-13 21:32:54 +01:00 · 2018-07-13 12:32:27 +01:00 · 2018-07-13 00:52:12 +01:00 · 2018-07-10 19:52:27 +01:00 · 2018-07-10 02:08:06 +01:00 · 2018-07-10 00:26:02 +00:00
22 changed files with 2425 additions and 2 deletions
--- a/ActivityPubPlugin.php
+++ b/ActivityPubPlugin.php
@ -0,0 +1,244 @@
+<?php
+require_once __DIR__ . DIRECTORY_SEPARATOR . "utils" . DIRECTORY_SEPARATOR . "postman.php";
+/**
+ * GNU social - a federating social network
+ *
+ * ActivityPubPlugin implementation for GNU Social
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @copyright 2018 Free Software Foundation http://fsf.org
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      https://www.gnu.org/software/social/
+ */
+if (!defined ('GNUSOCIAL')) {
+        exit (1);
+}
+
+/**
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      http://www.gnu.org/software/social/
+ */
+class ActivityPubPlugin extends Plugin
+{
+        /**
+         * Route/Reroute urls
+         *
+         * @param URLMapper $m
+         * @return void
+         */
+        public function onRouterInitialized (URLMapper $m)
+        {
+                ActivityPubURLMapperOverwrite::overwrite_variable ($m, ':nickname',
+                                            ['action' => 'showstream'],
+                                            ['nickname' => Nickname::DISPLAY_FMT],
+                                            'apActorProfile');
+
+                $m->connect (':nickname/liked.json',
+                            ['action'    => 'apActorLikedCollection'],
+                            ['nickname'  => Nickname::DISPLAY_FMT]);
+
+                $m->connect (':nickname/followers.json',
+                            ['action'    => 'apActorFollowers'],
+                            ['nickname'  => Nickname::DISPLAY_FMT]);
+
+                $m->connect (':nickname/following.json',
+                            ['action'    => 'apActorFollowing'],
+                            ['nickname'  => Nickname::DISPLAY_FMT]);
+
+                $m->connect (':nickname/inbox.json',
+                            ['action'    => 'apActorInbox'],
+                            ['nickname'  => Nickname::DISPLAY_FMT]);
+
+                $m->connect ('inbox.json',
+                            array ('action' => 'apSharedInbox'));
+
+                $m->connect ('api/statuses/public_timeline.as2',
+                            array ('action' => 'apFeed'));
+        }
+
+        /**
+         * Plugin version information
+         *
+         * @param array $versions
+         * @return boolean true
+         */
+        public function onPluginVersion (array &$versions)
+        {
+                $versions[] = [ 'name' => 'ActivityPub',
+                                'version' => GNUSOCIAL_VERSION,
+                                'author' => 'Daniel Supernault, Diogo Cordeiro',
+                                'homepage' => 'https://www.gnu.org/software/social/',
+                                'rawdescription' =>
+                                // Todo: Translation
+                                'Adds ActivityPub Support'];
+
+                return true;
+        }
+
+        /**
+         * Make sure necessary tables are filled out.
+         */
+        function onCheckSchema ()
+        {
+            $schema = Schema::get ();
+            $schema->ensureTable ('Activitypub_profile', Activitypub_profile::schemaDef());
+            return true;
+        }
+
+            /********************************************************
+             *                    Delivery Events                   *
+             ********************************************************/
+
+        /**
+         * Having established a remote subscription, send a notification to the
+         * remote ActivityPub profile's endpoint.
+         *
+         * @param Profile $profile  subscriber
+         * @param Profile $other    subscribee
+         * @return hook return value
+         * @throws Exception
+         */
+        function onEndSubscribe (Profile $profile, Profile $other)
+        {
+                if (!$profile->isLocal () || $other->isLocal ()) {
+                        return true;
+                }
+
+                try {
+                        $other = Activitypub_profile::fromProfile ($other);
+                } catch (Exception $e) {
+                        return true;
+                }
+
+                $postman = new Activitypub_postman ($profile, array ($other));
+
+                $postman->follow ();
+
+                return true;
+        }
+
+        /**
+         * Notify remote server on unsubscribe.
+         *
+         * @param Profile $profile
+         * @param Profile $other
+         * @return hook return value
+         */
+        function onEndUnsubscribe (Profile $profile, Profile $other)
+        {
+                if (!$profile->isLocal () || $other->isLocal ()) {
+                        return true;
+                }
+
+                try {
+                        $other = Activitypub_profile::fromProfile ($other);
+                } catch (Exception $e) {
+                        return true;
+                }
+
+                $postman = new Activitypub_postman ($profile, array ($other));
+
+                $postman->undo_follow ();
+
+                return true;
+        }
+
+        function onEndShowExportData (Action $action)
+        {
+                $action->elementStart ('div', array ('id' => 'export_data',
+                                                      'class' => 'section'));
+                $action->elementStart ('ul', array ('class' => 'xoxo'));
+
+                $action->elementStart ('li');
+                $action->element ('a', array ('href' => common_root_url ()."api/statuses/public_timeline.as2",
+                                               'class' => "json",
+                                               'type' => "application/activity+json",
+                                               'title' => "Public Timeline Feed (Activity Streams 2 JSON)"),
+                                    "Activity Streams 2");
+                $action->elementEnd ('li');
+
+                $action->elementEnd ('ul');
+                $action->elementEnd ('div');
+        }
+}
+
+/**
+ * Overwrites variables in URL-mapping
+ */
+class ActivityPubURLMapperOverwrite extends URLMapper
+{
+        static function overwrite_variable ($m, $path, $args, $paramPatterns, $newaction) {
+                $mimes = [
+                    'application/activity+json',
+                    'application/ld+json',
+                    'application/ld+json; profile="https://www.w3.org/ns/activitystreams"'
+                ];
+
+                if (in_array ($_SERVER["HTTP_ACCEPT"], $mimes) == false) {
+                        return true;
+                }
+
+                $m->connect ($path, array('action' => $newaction), $paramPatterns);
+                $regex = self::makeRegex($path, $paramPatterns);
+                foreach ($m->variables as $n => $v) {
+                        if ($v[1] == $regex) {
+                                $m->variables[$n][0]['action'] = $newaction;
+                        }
+                }
+        }
+}
+
+/**
+ * Plugin return handler
+ */
+class ActivityPubReturn
+{
+        /**
+         * Return a valid answer
+         *
+         * @param array $res
+         * @return void
+         */
+        static function answer ($res)
+        {
+                header ('Content-Type: application/activity+json');
+                echo json_encode ($res, JSON_UNESCAPED_SLASHES | (isset ($_GET["pretty"]) ? JSON_PRETTY_PRINT : null));
+                exit;
+        }
+
+        /**
+         * Return an error
+         *
+         * @param string $m
+         * @param int32 $code
+         * @return void
+         */
+        static function error ($m, $code = 500)
+        {
+                http_response_code ($code);
+                header ('Content-Type: application/activity+json');
+                $res[] = Activitypub_error::error_message_to_array ($m);
+                echo json_encode ($res, JSON_UNESCAPED_SLASHES);
+                exit;
+        }
+}
--- a/README.md
+++ b/README.md
@ -1,3 +1,2 @@
 # ActivityPub GNU/Social Plugin
-
-Warning: This is still a work in progress, not every ActivityPub property is fully implemented yet.
+Warning: This is still a work in progress, not every ActivityPub property is fully implemented yet.
--- a/actions/apactorfollowers.php
+++ b/actions/apactorfollowers.php
@ -0,0 +1,114 @@
+<?php
+/**
+ * GNU social - a federating social network
+ *
+ * ActivityPubPlugin implementation for GNU Social
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @copyright 2018 Free Software Foundation http://fsf.org
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      https://www.gnu.org/software/social/
+ */
+if (!defined ('GNUSOCIAL')) {
+        exit (1);
+}
+
+/**
+ * Actor's Followers Collection
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      http://www.gnu.org/software/social/
+ */
+class apActorFollowersAction extends ManagedAction
+{
+        protected $needLogin = false;
+        protected $canPost   = true;
+
+        /**
+         * Handle the Followers Collection request
+         *
+         * @return void
+         */
+        protected function handle ()
+        {
+                $nickname = $this->trimmed ('nickname');
+                try {
+                        $user    = User::getByNickname ($nickname);
+                        $profile = $user->getProfile ();
+                        $url     = $profile->profileurl;
+                } catch (Exception $e) {
+                        ActivityPubReturn::error ('Invalid username.');
+                }
+
+                if (!isset ($_GET["page"])) {
+                        $page = 1;
+                } else {
+                        $page = intval ($this->trimmed ('page'));
+                }
+
+                if ($page <= 0) {
+                        ActivityPubReturn::error ('Invalid page number.');
+                }
+
+                /* Fetch Followers */
+                try {
+                        $since = ($page - 1) * PROFILES_PER_MINILIST;
+                        $limit = (($page - 1) == 0 ? 1 : $page) * PROFILES_PER_MINILIST;
+                        $sub   = $profile->getSubscribers ($since, $limit);
+                } catch (NoResultException $e) {
+                        ActivityPubReturn::error ('This user has no followers.');
+                }
+
+                /* Calculate total items */
+                $total_subs  = $profile->subscriberCount ();
+                $total_pages = ceil ($total_subs / PROFILES_PER_MINILIST);
+
+                if ($total_pages == 0) {
+                        ActivityPubReturn::error ('This user has no followers.');
+                }
+
+                if ($page > $total_pages) {
+                        ActivityPubReturn::error ("There are only {$total_pages} pages.");
+                }
+
+                /* Get followers' URLs */
+                $subs = array ();
+                while ($sub->fetch ()) {
+                        $subs[] = $sub->profileurl;
+                }
+
+                $res = [
+                  '@context'     => [
+                    "https://www.w3.org/ns/activitystreams",
+                    "https://w3id.org/security/v1",
+                  ],
+                  'id'           => "{$url}/followers.json",
+                  'type'         => ($page == 0 ? 'OrderedCollection' : 'OrderedCollectionPage'),
+                  'totalItems'   => $total_subs,
+                  'next'         => $page+1 > $total_pages ? null : "{$url}/followers.json?page=".($page+1 == 1 ? 2 : $page+1),
+                  'prev'         => $page == 1 ? null : "{$url}/followers.json?page=".($page-1 <= 0 ? 1 : $page-1),
+                  'orderedItems' => $subs
+                ];
+
+                ActivityPubReturn::answer ($res);
+        }
+}
--- a/actions/apactorfollowing.php
+++ b/actions/apactorfollowing.php
@ -0,0 +1,114 @@
+<?php
+/**
+ * GNU social - a federating social network
+ *
+ * ActivityPubPlugin implementation for GNU Social
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @copyright 2018 Free Software Foundation http://fsf.org
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      https://www.gnu.org/software/social/
+ */
+if (!defined ('GNUSOCIAL')) {
+        exit (1);
+}
+
+/**
+ * Actor's Following Collection
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      http://www.gnu.org/software/social/
+ */
+class apActorFollowingAction extends ManagedAction
+{
+        protected $needLogin = false;
+        protected $canPost   = true;
+
+        /**
+         * Handle the Following Collection request
+         *
+         * @return void
+         */
+        protected function handle ()
+        {
+                $nickname = $this->trimmed ('nickname');
+                try {
+                        $user    = User::getByNickname ($nickname);
+                        $profile = $user->getProfile ();
+                        $url     = $profile->profileurl;
+                } catch (Exception $e) {
+                        ActivityPubReturn::error ('Invalid username.');
+                }
+
+                if (!isset ($_GET["page"])) {
+                        $page = 1;
+                } else {
+                        $page = intval ($this->trimmed ('page'));
+                }
+
+                if ($page <= 0) {
+                        ActivityPubReturn::error ('Invalid page number.');
+                }
+
+                /* Fetch Following */
+                try {
+                        $since = ($page - 1) * PROFILES_PER_MINILIST;
+                        $limit = (($page - 1) == 0 ? 1 : $page) * PROFILES_PER_MINILIST;
+                        $sub   = $profile->getSubscribed ($since, $limit);
+                } catch (NoResultException $e) {
+                        ActivityPubReturn::error ('This user is not following anyone.');
+                }
+
+                /* Calculate total items */
+                $total_subs  = $profile->subscriptionCount();
+                $total_pages = ceil ($total_subs / PROFILES_PER_MINILIST);
+
+                if ($total_pages == 0) {
+                        ActivityPubReturn::error ('This user is not following anyone.');
+                }
+
+                if ($page > $total_pages) {
+                        ActivityPubReturn::error ("There are only {$total_pages} pages.");
+                }
+
+                /* Get followed' URLs */
+                $subs = array ();
+                while ($sub->fetch ()) {
+                        $subs[] = $sub->profileurl;
+                }
+
+                $res = [
+                  '@context'     => [
+                    "https://www.w3.org/ns/activitystreams",
+                    "https://w3id.org/security/v1",
+                  ],
+                  'id'           => "{$url}/following.json",
+                  'type'         => ($page == 0 ? 'OrderedCollection' : 'OrderedCollectionPage'),
+                  'totalItems'   => $total_subs,
+                  'next'         => $page+1 > $total_pages ? null : "{$url}/followers.json?page=".($page+1 == 1 ? 2 : $page+1),
+                  'prev'         => $page == 1 ? null : "{$url}/followers.json?page=".($page-1 <= 0 ? 1 : $page-1),
+                  'orderedItems' => $subs
+                ];
+
+                ActivityPubReturn::answer ($res);
+        }
+}
--- a/actions/apactorinbox.php
+++ b/actions/apactorinbox.php
@ -0,0 +1,115 @@
+<?php
+/**
+ * GNU social - a federating social network
+ *
+ * ActivityPubPlugin implementation for GNU Social
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @copyright 2018 Free Software Foundation http://fsf.org
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      https://www.gnu.org/software/social/
+ */
+if (!defined ('GNUSOCIAL')) {
+        exit (1);
+}
+
+/**
+ * Actor's Inbox
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      http://www.gnu.org/software/social/
+ */
+class apActorInboxAction extends ManagedAction
+{
+        protected $needLogin = false;
+        protected $canPost   = true;
+
+        /**
+         * Handle the Actor Inbox request
+         *
+         * @return void
+         */
+        protected function handle ()
+        {
+                $nickname  = $this->trimmed ('nickname');
+                try {
+                        $user    = User::getByNickname ($nickname);
+                        $profile = $user->getProfile ();
+                        $url     = $profile->profileurl;
+                } catch (Exception $e) {
+                        ActivityPubReturn::error ("Invalid username.");
+                }
+
+                if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
+                        ActivityPubReturn::error ("C2S not implemented just yet.");
+                }
+
+                $data = json_decode (file_get_contents ('php://input'));
+
+                // Validate data
+                if (!(isset($data->type))) {
+                        ActivityPubReturn::error ("Type was not specified.");
+                }
+                if (!isset($data->actor)) {
+                        ActivityPubReturn::error ("Actor was not specified.");
+                }
+                if (!isset($data->object)) {
+                        ActivityPubReturn::error ("Object was not specified.");
+                }
+
+                // Get valid Actor object
+                try {
+                        require_once dirname (__DIR__) . DIRECTORY_SEPARATOR . "utils" . DIRECTORY_SEPARATOR . "explorer.php";
+                        $actor_profile = new Activitypub_explorer;
+                        $actor_profile = $actor_profile->lookup ($data->actor);
+                        $actor_profile = $actor_profile[0];
+                } catch (Exception $e) {
+                        ActivityPubReturn::error ("Invalid Actor.", 404);
+                }
+
+                $to_profiles = array ($user);
+
+                // Process request
+                switch ($data->type) {
+                        case "Create":
+                                require_once __DIR__ . DIRECTORY_SEPARATOR . "inbox" . DIRECTORY_SEPARATOR . "Create.php";
+                                break;
+                        case "Delete":
+                                require_once __DIR__ . DIRECTORY_SEPARATOR . "inbox" . DIRECTORY_SEPARATOR . "Delete.php";
+                                break;
+                        case "Follow":
+                                require_once __DIR__ . DIRECTORY_SEPARATOR . "inbox" . DIRECTORY_SEPARATOR . "Follow.php";
+                                break;
+                        case "Like":
+                                require_once __DIR__ . DIRECTORY_SEPARATOR . "inbox" . DIRECTORY_SEPARATOR . "Like.php";
+                                break;
+                        case "Undo":
+                                require_once __DIR__ . DIRECTORY_SEPARATOR . "inbox" . DIRECTORY_SEPARATOR . "Undo.php";
+                                break;
+                        case "Announce":
+                                require_once __DIR__ . DIRECTORY_SEPARATOR . "inbox" . DIRECTORY_SEPARATOR . "Announce.php";
+                                break;
+                        default:
+                                ActivityPubReturn::error ("Invalid type value.");
+                }
+        }
+}
--- a/actions/apactorlikedcollection.php
+++ b/actions/apactorlikedcollection.php
@ -0,0 +1,146 @@
+<?php
+/**
+ * GNU social - a federating social network
+ *
+ * ActivityPubPlugin implementation for GNU Social
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @copyright 2018 Free Software Foundation http://fsf.org
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      https://www.gnu.org/software/social/
+ */
+if (!defined ('GNUSOCIAL')) {
+        exit (1);
+}
+
+/**
+ * Actor's Liked Collection
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      http://www.gnu.org/software/social/
+ */
+class apActorLikedCollectionAction extends ManagedAction
+{
+        protected $needLogin = false;
+        protected $canPost   = true;
+
+        /**
+         * Handle the Liked Collection request
+         *
+         * @return void
+         */
+        protected function handle ()
+        {
+                $nickname = $this->trimmed ('nickname');
+                try {
+                        $user    = User::getByNickname ($nickname);
+                        $profile = $user->getProfile ();
+                        $url     = $profile->profileurl;
+                } catch (Exception $e) {
+                        ActivityPubReturn::error ('Invalid username.');
+                }
+
+                $limit    = intval ($this->trimmed ('limit'));
+                $since_id = intval ($this->trimmed ('since_id'));
+                $max_id   = intval ($this->trimmed ('max_id'));
+
+                $limit    = empty ($limit) ? 40 : $limit;       // Default is 40
+                $since_id = empty ($since_id) ? null : $since_id;
+                $max_id   = empty ($max_id) ? null : $max_id;
+
+                // Max is 80
+                if ($limit > 80) {
+                        $limit = 80;
+                }
+
+                $fave = $this->fetch_faves($user->getID(), $limit, $since_id, $max_id);
+
+                $faves = array();
+                while ($fave->fetch ()) {
+                        $faves[] = $this->pretty_fave (clone ($fave));
+                }
+
+                $res = [
+                  '@context'          => [
+                    "https://www.w3.org/ns/activitystreams",
+                    [
+                      "@language" => "en"
+                    ]
+                  ],
+                  'id'           => "{$url}/liked.json",
+                  'type'         => 'OrderedCollection',
+                  'totalItems'   => Fave::countByProfile ($profile),
+                  'orderedItems' => $faves
+                ];
+
+                ActivityPubReturn::answer ($res);
+        }
+
+        /**
+         * Take a fave object and turns it in a pretty array to be used
+         * as a plugin answer
+         *
+         * @param Fave $fave_object
+         * @return array pretty array representating a Fave
+         */
+        protected function pretty_fave ($fave_object)
+        {
+                $res = array("uri" => $fave_object->uri,
+                             "created" => $fave_object->created,
+                             "object" => Activitypub_notice::notice_to_array (Notice::getByID ($fave_object->notice_id)));
+
+                return $res;
+        }
+
+        /**
+         * Fetch faves
+         *
+         * @param int32 $user_id
+         * @param int32 $limit
+         * @param int32 $since_id
+         * @param int32 $max_id
+         * @return Fave fetchable fave collection
+         */
+        private static function fetch_faves ($user_id, $limit = 40, $since_id = null,
+                                             $max_id = null)
+        {
+                $fav = new Fave ();
+
+                $fav->user_id = $user_id;
+
+                $fav->orderBy ('modified DESC');
+
+                if ($since_id != null) {
+                        $fav->whereAdd ("notice_id  > {$since_id}");
+                }
+
+                if ($max_id != null) {
+                        $fav->whereAdd ("notice_id  < {$max_id}");
+                }
+
+                $fav->limit ($limit);
+
+                $fav->find ();
+
+                return $fav;
+        }
+}
--- a/actions/apactorprofile.php
+++ b/actions/apactorprofile.php
@ -0,0 +1,67 @@
+<?php
+/**
+ * GNU social - a federating social network
+ *
+ * ActivityPubPlugin implementation for GNU Social
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @copyright 2018 Free Software Foundation http://fsf.org
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      https://www.gnu.org/software/social/
+ */
+if (!defined ('GNUSOCIAL')) {
+        exit (1);
+}
+
+/**
+ * Actor's profile (Local users only)
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      http://www.gnu.org/software/social/
+ */
+class apActorProfileAction extends ManagedAction
+{
+        protected $needLogin = false;
+        protected $canPost   = true;
+
+        /**
+         * Handle the Actor Profile request
+         *
+         * @return void
+         */
+        protected function handle()
+        {
+                $nickname = $this->trimmed ('nickname');
+                try {
+                        $user    = User::getByNickname ($nickname);
+                        $profile = $user->getProfile ();
+                }
+                catch (Exception $e) {
+                        ActivityPubReturn::error ('Invalid username.', 404);
+                }
+
+                $res = Activitypub_profile::profile_to_array ($profile);
+
+                ActivityPubReturn::answer ($res);
+        }
+}
--- a/actions/apfeed.php
+++ b/actions/apfeed.php
@ -0,0 +1,342 @@
+<?php
+/**
+ * GNU social - a federating social network
+ *
+ * ActivityPubPlugin implementation for GNU Social
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @copyright 2018 Free Software Foundation http://fsf.org
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      https://www.gnu.org/software/social/
+ */
+if (!defined('GNUSOCIAL')) {
+        exit(1);
+}
+
+/**
+ * ActivityPub Feed
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      http://www.gnu.org/software/social/
+ */
+class apFeedAction extends ManagedAction
+{
+        protected $needLogin = false;
+        protected $canPost = true;
+
+        var $page = 1;
+        var $count = 20;
+        var $max_id = 0;
+        var $since_id = 0;
+
+        /**
+         * Handle the Actor Inbox request
+         *
+         * @return void
+         */
+        protected function handle ()
+        {
+                $this->showJsonTimeline($this->getNotices());
+        }
+
+        /**
+         * Get notices
+         *
+         * @return array notices
+         */
+         function getNotices()
+         {
+                $notices = array ();
+
+                $stream = new PublicNoticeStream (null);
+
+                $notice = $stream->getNotices (($this->page - 1) * $this->count,
+                                              $this->count,
+                                              $this->since_id, $this->max_id);
+
+                $notices = $notice->fetchAll ();
+
+                NoticeList::prefill ($notices);
+
+                return $notices;
+        }
+
+        function showJsonTimeline ($notice)
+        {
+                header ('Content-Type: application/json; charset=utf-8');
+
+                $statuses = array ();
+
+                if (is_array ($notice)) {
+                        //FIXME: make everything calling showJsonTimeline use only Notice objects
+                        $ids = array ();
+                        foreach($notice as $n) {
+                                $ids[] = $n->getID ();
+                        }
+                        $notice = Notice::multiGet ('id', $ids);
+                }
+
+                while ($notice->fetch ()) {
+                        try {
+                                $twitter_status = $this->twitterStatusArray ($notice);
+                                array_push ($statuses, $twitter_status);
+                        } catch (Exception $e) {
+                                common_log (LOG_ERR, $e->getMessage ());
+                                continue;
+                        }
+                }
+
+                $this->showJsonObjects ($statuses);
+        }
+
+        function showJsonObjects ($objects)
+        {
+                $json_objects = json_encode ($objects);
+                if ($json_objects === false) {
+                        $this-> clientError(_('JSON encoding failed. Error: ').json_last_error_msg ());
+                } else {
+                        print $json_objects;
+                }
+        }
+
+        function twitterStatusArray ($notice, $include_user = true)
+        {
+                $base = $this->twitterSimpleStatusArray ($notice, $include_user);
+
+                // FIXME: MOVE TO SHARE PLUGIN
+                if (!empty ($notice->repeat_of)) {
+                        $original = Notice::getKV ('id', $notice->repeat_of);
+                        if ($original instanceof Notice) {
+                                $orig_array = $this->twitterSimpleStatusArray($original, $include_user);
+                                $base['retweeted_status'] = $orig_array;
+                        }
+                }
+
+                return $base;
+        }
+
+        function twitterSimpleStatusArray ($notice, $include_user = true)
+        {
+                $profile = $notice->getProfile ();
+
+                $twitter_status = array ();
+                $twitter_status['text'] = $notice->content;
+                $twitter_status['truncated'] = false;
+                $twitter_status['created_at'] = self::dateTwitter ($notice->created);
+                try {
+                        // We could just do $notice->reply_to but maybe the future holds a
+                        // different story for parenting.
+                        $parent = $notice->getParent ();
+                        $in_reply_to = $parent->id;
+                } catch (NoParentNoticeException $e) {
+                        $in_reply_to = null;
+                } catch (NoResultException $e) {
+                        // the in_reply_to message has probably been deleted
+                        $in_reply_to = null;
+                }
+                $twitter_status['in_reply_to_status_id'] = $in_reply_to;
+
+                $source = null;
+                $source_link = null;
+
+                $ns = $notice->getSource ();
+                if ($ns instanceof Notice_source) {
+                        $source = $ns->code;
+                        if (!empty ($ns->url)) {
+                                $source_link = $ns->url;
+                                if (!empty ($ns->name)) {
+                                        $source = $ns->name;
+                                }
+                        }
+                }
+
+                $twitter_status['uri'] = $notice->getUri ();
+                $twitter_status['source'] = $source;
+                $twitter_status['source_link'] = $source_link;
+                $twitter_status['id'] = intval ($notice->id);
+
+                $replier_profile = null;
+
+                if ($notice->reply_to) {
+                        $reply = Notice::getKV (intval ($notice->reply_to));
+                        if ($reply) {
+                                $replier_profile = $reply->getProfile ();
+                        }
+                }
+
+                $twitter_status['in_reply_to_user_id'] =
+                    ($replier_profile) ? intval ($replier_profile->id) : null;
+                $twitter_status['in_reply_to_screen_name'] =
+                    ($replier_profile) ? $replier_profile->nickname : null;
+
+                try {
+                        $notloc = Notice_location::locFromStored ($notice);
+                        // This is the format that GeoJSON expects stuff to be in
+                        $twitter_status['geo'] = array ('type' => 'Point',
+                                                        'coordinates' => array (
+                                                            (float) $notloc->lat,
+                                                            (float) $notloc->lon));
+                } catch (ServerException $e) {
+                        $twitter_status['geo'] = null;
+                }
+
+                // Enclosures
+                $attachments = $notice->attachments ();
+
+                if (!empty ($attachments)) {
+
+                        $twitter_status['attachments'] = array ();
+
+                        foreach ($attachments as $attachment) {
+                                try {
+                                        $enclosure_o = $attachment->getEnclosure ();
+                                        $enclosure = array();
+                                        $enclosure['url'] = $enclosure_o->url;
+                                        $enclosure['mimetype'] = $enclosure_o->mimetype;
+                                        $enclosure['size'] = $enclosure_o->size;
+                                        $twitter_status['attachments'][] = $enclosure;
+                                } catch (ServerException $e) {
+                                        // There was not enough metadata available
+                                }
+                        }
+                }
+
+                if ($include_user && $profile) {
+                        // Don't get notice (recursive!)
+                        $twitter_user = $this->twitterUserArray($profile, false);
+                        $twitter_status['user'] = $twitter_user;
+                }
+                // StatusNet-specific
+
+                $twitter_status['statusnet_html'] = $notice->getRendered();
+                $twitter_status['statusnet_conversation_id'] = intval($notice->conversation);
+
+                // The event call to handle NoticeSimpleStatusArray lets plugins add data to the output array
+                Event::handle('NoticeSimpleStatusArray',
+                              array ($notice, &$twitter_status, $this->scoped,
+                                    array ('include_user' => $include_user)));
+
+                return $twitter_status;
+        }
+
+        static function dateTwitter($dt)
+        {
+                $dateStr = date ('d F Y H:i:s', strtotime ($dt));
+                $d = new DateTime ($dateStr, new DateTimeZone ('UTC'));
+                $d->setTimezone (new DateTimeZone(common_timezone()));
+                return $d->format ('D M d H:i:s O Y');
+        }
+
+        function twitterUserArray ($profile, $get_notice = false)
+        {
+                $twitter_user = array ();
+
+                try {
+                        $user = $profile->getUser ();
+                } catch (NoSuchUserException $e) {
+                        $user = null;
+                }
+
+                $twitter_user['id'] = $profile->getID ();
+                $twitter_user['name'] = $profile->getBestName ();
+                $twitter_user['screen_name'] = $profile->getNickname ();
+                $twitter_user['location'] = $profile->location;
+                $twitter_user['description'] = $profile->getDescription ();
+
+                // TODO: avatar url template (example.com/user/avatar?size={x}x{y})
+                $twitter_user['profile_image_url'] = Avatar::urlByProfile($profile, AVATAR_STREAM_SIZE);
+                $twitter_user['profile_image_url_https'] = $twitter_user['profile_image_url'];
+
+                // START introduced by qvitter API, not necessary for StatusNet API
+                $twitter_user['profile_image_url_profile_size'] = Avatar::urlByProfile($profile, AVATAR_PROFILE_SIZE);
+                try {
+                        $avatar = Avatar::getUploaded ($profile);
+                        $origurl = $avatar->displayUrl ();
+                } catch(Exception $e) {
+                        $origurl = $twitter_user['profile_image_url_profile_size'];
+                }
+                $twitter_user['profile_image_url_original'] = $origurl;
+
+                $twitter_user['groups_count'] = $profile->getGroupCount();
+                foreach (array('linkcolor', 'backgroundcolor') as $key) {
+                        $twitter_user[$key] =  Profile_prefs::getConfigData($profile, 'theme', $key);
+                }
+                // END introduced by qvitter API, not necessary for StatusNet API
+
+                $twitter_user['url'] = ($profile->homepage) ? $profile->homepage : null;
+                $twitter_user['protected'] = (!empty($user) && $user->private_stream) ? true : false;
+                $twitter_user['followers_count'] = $profile->subscriberCount();
+
+                // Note: some profiles don't have an associated user
+
+                $twitter_user['friends_count'] = $profile->subscriptionCount ();
+
+                $twitter_user['created_at'] = self::dateTwitter($profile->created);
+
+                $timezone = 'UTC';
+
+                if (!empty($user) && $user->timezone) {
+                        $timezone = $user->timezone;
+                }
+
+                $t = new DateTime;
+                $t->setTimezone (new DateTimeZone ($timezone));
+
+                $twitter_user['utc_offset']     = $t->format('Z');
+                $twitter_user['time_zone']      = $timezone;
+                $twitter_user['statuses_count'] = $profile->noticeCount();
+
+                // Is the requesting user following this user?
+                // These values might actually also mean "unknown". Ambiguity issues?
+                $twitter_user['following']          = false;
+                $twitter_user['statusnet_blocking'] = false;
+                $twitter_user['notifications']      = false;
+
+                if ($this->scoped instanceof Profile) {
+                        try {
+                                $sub = Subscription::getSubscription($this->scoped, $profile);
+                                // Notifications on?
+                                $twitter_user['following'] = true;
+                                $twitter_user['notifications'] = ($sub->jabber || $sub->sms);
+                        } catch (NoResultException $e) {
+                                // well, the values are already false...
+                        }
+                        $twitter_user['statusnet_blocking'] = $this->scoped->hasBlocked($profile);
+                }
+
+                if ($get_notice) {
+                        $notice = $profile->getCurrentNotice ();
+                        if ($notice instanceof Notice) {
+                                // don't get user!
+                                $twitter_user['status'] = $this->twitterStatusArray($notice, false);
+                        }
+                }
+                // StatusNet-specific
+
+                $twitter_user['statusnet_profile_url'] = $profile->profileurl;
+
+                // The event call to handle NoticeSimpleStatusArray lets plugins add data to the output array
+                Event::handle('TwitterUserArray', array ($profile, &$twitter_user, $this->scoped, array()));
+
+                return $twitter_user;
+        }
+}
--- a/actions/apsharedinbox.php
+++ b/actions/apsharedinbox.php
@ -0,0 +1,135 @@
+<?php
+require_once dirname (__DIR__) . DIRECTORY_SEPARATOR . "utils" . DIRECTORY_SEPARATOR . "explorer.php";
+/**
+ * GNU social - a federating social network
+ *
+ * ActivityPubPlugin implementation for GNU Social
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @copyright 2018 Free Software Foundation http://fsf.org
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      https://www.gnu.org/software/social/
+ */
+if (!defined ('GNUSOCIAL')) {
+        exit (1);
+}
+
+/**
+ * Shared Inbox Handler
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      http://www.gnu.org/software/social/
+ */
+class apSharedInboxAction extends ManagedAction
+{
+        protected $needLogin = false;
+        protected $canPost   = true;
+
+        /**
+         * Handle the Shared Inbox request
+         *
+         * @return void
+         */
+        protected function handle ()
+        {
+                if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
+                        ActivityPubReturn::error ("Only POST requests allowed.");
+                }
+
+                $data = json_decode (file_get_contents ('php://input'));
+
+                // Validate data
+                if (!isset($data->type)) {
+                        ActivityPubReturn::error ("Type was not specified.");
+                }
+                if (!isset($data->actor)) {
+                        ActivityPubReturn::error ("Actor was not specified.");
+                }
+                if (!isset($data->object)) {
+                        ActivityPubReturn::error ("Object was not specified.");
+                }
+
+                $discovery = new Activitypub_explorer;
+
+                // Get valid Actor object
+                try {
+                        $actor_profile = $discovery->lookup ($data->actor);
+                        $actor_profile = $actor_profile[0];
+                } catch (Exception $e) {
+                        ActivityPubReturn::error ("Invalid Actor.", 404);
+                }
+
+                unset ($discovery);
+
+                // Public To:
+                $public_to = array ("https://www.w3.org/ns/activitystreams#Public",
+                                    "Public",
+                                    "as:Public");
+
+                // Process request
+                switch ($data->type) {
+                        case "Create":
+                                if (!isset($data->to)) {
+                                        ActivityPubReturn::error ("To was not specified.");
+                                }
+                                $discovery = new Activitypub_Discovery;
+                                $to_profiles = array ();
+                                // Generate To objects
+                                if (is_array ($data->to)) {
+                                        // Remove duplicates from To actors set
+                                        array_unique ($data->to);
+                                        foreach ($data->to as $to_url) {
+                                                try {
+                                                        $to_profiles = array_merge ($to_profiles, $discovery->lookup ($to_url));
+                                                } catch (Exception $e) {
+                                                        // XXX: Invalid actor found, not sure how we handle those
+                                                }
+                                        }
+                                } else if (empty ($data->to) || in_array ($data->to, $public_to)) {
+                                        // No need to do anything else at this point, let's just break out the if
+                                } else {
+                                        try {
+                                                $to_profiles[]= $discovery->lookup ($data->to);
+                                        } catch (Exception $e) {
+                                                ActivityPubReturn::error ("Invalid Actor.", 404);
+                                        }
+                                }
+                                unset ($discovery);
+                                require_once __DIR__ . DIRECTORY_SEPARATOR . "inbox" . DIRECTORY_SEPARATOR . "Create.php";
+                                break;
+                        case "Follow":
+                                require_once __DIR__ . DIRECTORY_SEPARATOR . "inbox" . DIRECTORY_SEPARATOR . "Follow.php";
+                                break;
+                        case "Like":
+                                require_once __DIR__ . DIRECTORY_SEPARATOR . "inbox" . DIRECTORY_SEPARATOR . "Like.php";
+                                break;
+                        case "Announce":
+                                require_once __DIR__ . DIRECTORY_SEPARATOR . "inbox" . DIRECTORY_SEPARATOR . "Announce.php";
+                                break;
+                        case "Undo":
+                                require_once __DIR__ . DIRECTORY_SEPARATOR . "inbox" . DIRECTORY_SEPARATOR . "Undo.php";
+                                break;
+                        default:
+                                ActivityPubReturn::error ("Invalid type value.");
+                }
+    }
+}
--- a/actions/inbox/Announce.php
+++ b/actions/inbox/Announce.php
@ -0,0 +1,37 @@
+<?php
+/**
+ * GNU social - a federating social network
+ *
+ * ActivityPubPlugin implementation for GNU Social
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @copyright 2018 Free Software Foundation http://fsf.org
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      https://www.gnu.org/software/social/
+ */
+if (!defined ('GNUSOCIAL')) {
+        exit (1);
+}
+
+try {
+        Notice::getByUri ($data->object)->repeat ($actor_profile, "ActivityPub");
+        ActivityPubReturn::answer ("Notice repeated successfully.");
+} catch (Exception $e) {
+        ActivityPubReturn::error ($e->getMessage (), 403);
+}
--- a/actions/inbox/Create.php
+++ b/actions/inbox/Create.php
@ -0,0 +1,93 @@
+<?php
+/**
+ * GNU social - a federating social network
+ *
+ * ActivityPubPlugin implementation for GNU Social
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @copyright 2018 Free Software Foundation http://fsf.org
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      https://www.gnu.org/software/social/
+ */
+if (!defined ('GNUSOCIAL')) {
+        exit (1);
+}
+
+$valid_object_types = array ("Note");
+
+// Validate data
+if (!(isset ($data->object->type) && in_array ($data->object->type, $valid_object_types))) {
+        ActivityPubReturn::error ("Invalid Object type.");
+}
+if (!isset ($data->object->content)) {
+        ActivityPubReturn::error ("Object content was not specified.");
+}
+
+$content = $data->object->content;
+
+$act = new Activity ();
+$act->verb = ActivityVerb::POST;
+$act->time = time ();
+$act->actor = $actor_profile->asActivityObject ();
+
+$act->context = new ActivityContext ();
+
+// Is this a reply?
+if (isset ($data->object->reply_to)) {
+        $reply_to = Notice::getByUri ($data->object->reply_to);
+        $act->context->replyToID = $reply_to->getUri ();
+        $act->context->replyToUrl = $data->object->reply_to;
+} else {
+        $reply_to = null;
+}
+
+$act->context->attention = common_get_attentions ($content, $actor_profile, $reply_to);
+
+foreach ($to_profiles as $to)
+{
+        $act->context->attention[$to->getUri ()] = "http://activitystrea.ms/schema/1.0/person";
+}
+
+// Reject notice if it is too long (without the HTML)
+// This is done after MediaFile::fromUpload etc. just to act the same as the ApiStatusesUpdateAction
+if (Notice::contentTooLong ($content)) {
+        ActivityPubReturn::error ("That's too long. Maximum notice size is %d character.");
+}
+
+$options = array ('source' => 'ActivityPub', 'uri' => $data->id);
+// $options gets filled with possible scoping settings
+ToSelector::fillActivity ($this, $act, $options);
+
+$actobj = new ActivityObject ();
+$actobj->type = ActivityObject::NOTE;
+$actobj->content = common_render_content ($content, $actor_profile, $reply_to);
+
+// Finally add the activity object to our activity
+$act->objects[] = $actobj;
+
+try {
+        $res = array ("@context" => "https://www.w3.org/ns/activitystreams",
+                  "id"     => $data->id,
+                  "type"   => "Create",
+                  "actor"  => $data->actor,
+                  "object" => Activitypub_notice::notice_to_array (Notice::saveActivity ($act, $actor_profile, $options)));
+        ActivityPubReturn::answer ($res);
+} catch (Exception $e) {
+        ActivityPubReturn::error ($e->getMessage ());
+}
--- a/actions/inbox/Delete.php
+++ b/actions/inbox/Delete.php
@ -0,0 +1,41 @@
+<?php
+/**
+ * GNU social - a federating social network
+ *
+ * ActivityPubPlugin implementation for GNU Social
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @copyright 2018 Free Software Foundation http://fsf.org
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      https://www.gnu.org/software/social/
+ */
+if (!defined ('GNUSOCIAL')) {
+        exit (1);
+}
+
+try {
+        Activitypub_notice::getByUri ($data->object)->deleteAs ($actor_profile);
+        $res = array ("@context" => "https://www.w3.org/ns/activitystreams",
+                  "type"   => "Delete",
+                  "actor"  => $data->actor,
+                  "object" => $data->object);
+        ActivityPubReturn::answer ($res);
+} catch (Exception $e) {
+        ActivityPubReturn::error ($e->getMessage (), 403);
+}
--- a/actions/inbox/Follow.php
+++ b/actions/inbox/Follow.php
@ -0,0 +1,58 @@
+<?php
+/**
+ * GNU social - a federating social network
+ *
+ * ActivityPubPlugin implementation for GNU Social
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @copyright 2018 Free Software Foundation http://fsf.org
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      https://www.gnu.org/software/social/
+ */
+if (!defined ('GNUSOCIAL')) {
+        exit (1);
+}
+
+// Validate Object
+if (!is_string ($data->object)) {
+        ActivityPubReturn::error ("Invalid Object object, URL expected.");
+}
+
+// Get valid Object profile
+try {
+        $object_profile = new Activitypub_explorer;
+        $object_profile = $object_profile->lookup ($data->object)[0];
+} catch(Exception $e) {
+        ActivityPubReturn::error ("Invalid Object Actor URL.", 404);
+}
+
+try {
+        if (!Subscription::exists ($actor_profile, $object_profile)) {
+                Subscription::start ($actor_profile, $object_profile);
+                $res = array ("@context" => "https://www.w3.org/ns/activitystreams",
+                          "type"   => "Follow",
+                          "actor"  => $data->actor,
+                          "object" => $data->object);
+                ActivityPubReturn::answer ($res);
+        } else {
+                ActivityPubReturn::error ("Already following.", 409);
+        }
+} catch (Exception $e) {
+        ActivityPubReturn::error ("Invalid Object Actor URL.", 404);
+}
--- a/actions/inbox/Like.php
+++ b/actions/inbox/Like.php
@ -0,0 +1,41 @@
+<?php
+/**
+ * GNU social - a federating social network
+ *
+ * ActivityPubPlugin implementation for GNU Social
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @copyright 2018 Free Software Foundation http://fsf.org
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      https://www.gnu.org/software/social/
+ */
+if (!defined ('GNUSOCIAL')) {
+        exit (1);
+}
+
+try {
+        Fave::addNew ($actor_profile, Notice::getByUri ($data->object));
+        $res = array ("@context" => "https://www.w3.org/ns/activitystreams",
+                  "type"   => "Like",
+                  "actor"  => $data->actor,
+                  "object" => $data->object);
+        ActivityPubReturn::answer ($res);
+} catch (Exception $e) {
+        ActivityPubReturn::error ($e->getMessage (), 403);
+}
--- a/actions/inbox/Undo.php
+++ b/actions/inbox/Undo.php
@ -0,0 +1,78 @@
+<?php
+/**
+ * GNU social - a federating social network
+ *
+ * ActivityPubPlugin implementation for GNU Social
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @copyright 2018 Free Software Foundation http://fsf.org
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      https://www.gnu.org/software/social/
+ */
+if (!defined ('GNUSOCIAL')) {
+        exit (1);
+}
+
+// Validate data
+if (!isset ($data->type)) {
+        ActivityPubReturn::error ("Type was not specified.");
+}
+
+switch ($data->object->type) {
+case "Like":
+        try {
+                // Validate data
+                if (!isset ($data->object->object)) {
+                        ActivityPubReturn::error ("Object Notice URL was not specified.");
+                }
+
+                Fave::removeEntry ($actor_profile, Notice::getByUri ($data->object->object));
+                ActivityPubReturn::answer ("Notice disfavorited successfully.");
+        } catch (Exception $e) {
+                ActivityPubReturn::error ($e->getMessage (), 403);
+        }
+        break;
+case "Follow":
+        // Validate data
+        if (!isset ($data->object->object)) {
+                ActivityPubReturn::error ("Object Actor URL was not specified.");
+        }
+        // Get valid Object profile
+        try {
+                $object_profile = new Activitypub_explorer;
+                $object_profile = $object_profile->lookup ($data->object->object)[0];
+        } catch (Exception $e) {
+                ActivityPubReturn::error ("Invalid Object Actor URL.", 404);
+        }
+
+        try {
+                if (Subscription::exists ($actor_profile, $object_profile)) {
+                        Subscription::cancel ($actor_profile, $object_profile);
+                        ActivityPubReturn::answer ("You are no longer following this person.");
+                } else {
+                        ActivityPubReturn::error ("You are not following this person already.", 409);
+                }
+        } catch (Exception $e) {
+                ActivityPubReturn::error ("Invalid Object Actor URL.", 404);
+        }
+        break;
+default:
+        ActivityPubReturn::error ("Invalid object type.");
+        break;
+}
--- a/classes/Activitypub_attachment.php
+++ b/classes/Activitypub_attachment.php
@ -0,0 +1,77 @@
+<?php
+/**
+ * GNU social - a federating social network
+ *
+ * ActivityPubPlugin implementation for GNU Social
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @copyright 2018 Free Software Foundation http://fsf.org
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      https://www.gnu.org/software/social/
+ */
+if (!defined ('GNUSOCIAL')) {
+        exit (1);
+}
+
+/**
+ * ActivityPub Attachment representation
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      http://www.gnu.org/software/social/
+ */
+class Activitypub_attachment extends Managed_DataObject
+{
+        /**
+         * Generates a pretty array from an Attachment object
+         *
+         * @param Attachment $attachment
+         * @return pretty array to be used in a response
+         */
+        public static function attachment_to_array ($attachment)
+        {
+                $res = [
+                        '@context'  => [
+                                "https://www.w3.org/ns/activitystreams",
+                                [
+                                        "@language" => "en"
+                                ]
+                        ],
+                        'id'       => $attachment->getID (),
+                        'mimetype' => $attachment->mimetype,
+                        'url'      => $attachment->getUrl (),
+                        'size'     => intval($attachment->size), // $attachment->getSize ()
+                        'title'    => $attachment->getTitle (),
+                        'meta'     => null
+                ];
+
+                // Image
+                if (substr ($res["mimetype"], 0, 5) == "image")
+                {
+                        $res["meta"]= [
+                                'width'  => $attachment->width,
+                                'height' => $attachment->height
+                        ];
+                }
+
+                return $res;
+        }
+}
--- a/classes/Activitypub_error.php
+++ b/classes/Activitypub_error.php
@ -0,0 +1,56 @@
+<?php
+/**
+ * GNU social - a federating social network
+ *
+ * ActivityPubPlugin implementation for GNU Social
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @copyright 2018 Free Software Foundation http://fsf.org
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      https://www.gnu.org/software/social/
+ */
+if (!defined ('GNUSOCIAL')) {
+        exit (1);
+}
+
+/**
+ * ActivityPub error representation
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      http://www.gnu.org/software/social/
+ */
+class Activitypub_error extends Managed_DataObject
+{
+        /**
+         * Generates a pretty error from a string
+         *
+         * @param string $m
+         * @return pretty array to be used in a response
+         */
+        public static function error_message_to_array ($m)
+        {
+                $res = [
+                        'error'=> $m
+                ];
+                return $res;
+        }
+}
--- a/classes/Activitypub_notice.php
+++ b/classes/Activitypub_notice.php
@ -0,0 +1,89 @@
+<?php
+/**
+ * GNU social - a federating social network
+ *
+ * ActivityPubPlugin implementation for GNU Social
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @copyright 2018 Free Software Foundation http://fsf.org
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      https://www.gnu.org/software/social/
+ */
+if (!defined ('GNUSOCIAL')) {
+        exit (1);
+}
+
+/**
+ * ActivityPub notice representation
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      http://www.gnu.org/software/social/
+ */
+class Activitypub_notice extends Managed_DataObject
+{
+        /**
+         * Generates a pretty notice from a Notice object
+         *
+         * @param Notice $notice
+         * @return pretty array to be used in a response
+         */
+        public static function notice_to_array ($notice)
+        {
+                $attachments = array ();
+                foreach($notice->attachments () as $attachment) {
+                        $attachments[] = Activitypub_attachment::attachment_to_array ($attachment);
+                }
+
+                $tags = array ();
+                foreach($notice->getTags()as $tag) {
+                        if ($tag != "") {       // Hacky workaround to avoid stupid outputs
+                                $tags[] = Activitypub_tag::tag_to_array ($tag);
+                        }
+                }
+
+                $to = array ();
+                foreach ($notice->getAttentionProfileIDs () as $to_id) {
+                        $to[] = Profile::getById ($to_id)->getUri ();
+                }
+                if (!is_null($to)) {
+                        $to = array ("https://www.w3.org/ns/activitystreams#Public");
+                }
+
+                $item = [
+                        'id'           => $notice->getUrl (),
+                        'type'         => 'Notice',
+                        'actor'        => $notice->getProfile ()->getUrl (),
+                        'published'    => $notice->getCreated (),
+                        'to'           => $to,
+                        'content'      => $notice->getContent (),
+                        'url'          => $notice->getUrl (),
+                        'reply_to'     => empty($notice->reply_to) ? null : Notice::getById($notice->reply_to)->getUrl (),
+                        'is_local'     => $notice->isLocal (),
+                        'conversation' => intval ($notice->conversation),
+                        'attachment'   => $attachments,
+                        'tag'          => $tags
+                ];
+
+                return $item;
+        }
+}
--- a/classes/Activitypub_profile.php
+++ b/classes/Activitypub_profile.php
@ -0,0 +1,204 @@
+<?php
+/**
+ * GNU social - a federating social network
+ *
+ * ActivityPubPlugin implementation for GNU Social
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @copyright 2018 Free Software Foundation http://fsf.org
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      https://www.gnu.org/software/social/
+ */
+if (!defined ('GNUSOCIAL')) {
+        exit (1);
+}
+
+/**
+ * ActivityPub Profile
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      http://www.gnu.org/software/social/
+ */
+class Activitypub_profile extends Profile
+{
+        public $__table = 'Activitypub_profile';
+
+        protected $_profile = null;
+
+        /**
+         * Return table definition for Schema setup and DB_DataObject usage.
+         *
+         * @return array array of column definitions
+         */
+        static function schemaDef ()
+        {
+            return array (
+                'fields' => array (
+                    'uri' => array ('type' => 'varchar', 'length' => 191, 'not null' => true),
+                    'profile_id' => array ('type' => 'integer'),
+                    'inboxuri' => array ('type' => 'varchar', 'length' => 191),
+                    'sharedInboxuri' => array ('type' => 'varchar', 'length' => 191),
+                    'created' => array ('type' => 'datetime', 'not null' => true),
+                    'modified' => array ('type' => 'datetime', 'not null' => true),
+                ),
+                'primary key' => array ('uri'),
+                'unique keys' => array (
+                    'Activitypub_profile_profile_id_key' => array ('profile_id'),
+                    'Activitypub_profile_inboxuri_key' => array ('inboxuri'),
+                ),
+                'foreign keys' => array (
+                    'Activitypub_profile_profile_id_fkey' => array ('profile', array ('profile_id' => 'id')),
+                ),
+            );
+        }
+
+        /**
+         * Generates a pretty profile from a Profile object
+         *
+         * @param Profile $profile
+         * @return pretty array to be used in a response
+         */
+        public static function profile_to_array ($profile)
+        {
+                $url = $profile->getURL ();
+                $res = [
+                        '@context'        => [
+                                "https://www.w3.org/ns/activitystreams",
+                                [
+                                        "@language"   => "en"
+                                ]
+                        ],
+                        'id'              => $profile->getID (),
+                        'type'            => 'Person',
+                        'nickname'        => $profile->getNickname (),
+                        'is_local'        => $profile->isLocal (),
+                        'inbox'           => "{$url}/inbox.json",
+                        'sharedInbox'     => common_root_url ()."inbox.json",
+                        'outbox'          => "{$url}/outbox.json",
+                        'display_name'    => $profile->getFullname (),
+                        'followers'       => "{$url}/followers.json",
+                        'followers_count' => $profile->subscriberCount (),
+                        'following'       => "{$url}/following.json",
+                        'following_count' => $profile->subscriptionCount (),
+                        'liked'           => "{$url}/liked.json",
+                        'liked_count'     => Fave::countByProfile ($profile),
+                        'summary'         => ($desc = $profile->getDescription ()) == null ? "" : $desc,
+                        'url'             => $profile->getURL (),
+                        'avatar'          => [
+                                'type'   => 'Image',
+                                'width'  => 96,
+                                'height' => 96,
+                                'url'    => $profile->avatarUrl (AVATAR_PROFILE_SIZE)
+                        ]
+                ];
+                return $res;
+        }
+
+        /**
+         * Insert the current objects variables into the database
+         *
+         * @access public
+         * @throws ServerException
+         */
+        public function doInsert ()
+        {
+                $profile = new Profile ();
+
+                $profile->created = $this->created = $this->modified = common_sql_now ();
+
+                $fields = array (
+                            'uri'      => 'profileurl',
+                            'nickname' => 'nickname',
+                            'fullname' => 'fullname',
+                            'bio'      => 'bio'
+                            );
+
+                foreach ($fields as $af => $pf) {
+                        $profile->$pf = $this->$af;
+                }
+
+                $this->profile_id = $profile->insert ();
+                if ($this->profile_id === false) {
+                        $profile->query ('ROLLBACK');
+                        throw new ServerException ('Profile insertion failed.');
+                }
+
+                $ok = $this->insert ();
+
+                if ($ok === false) {
+                        $profile->query ('ROLLBACK');
+                        throw new ServerException ('Cannot save ActivityPub profile.');
+                }
+        }
+
+        /**
+         * Fetch the locally stored profile for this Activitypub_profile
+         * @return Profile
+         * @throws NoProfileException if it was not found
+         */
+        public function localProfile ()
+        {
+                $profile = Profile::getKV ('id', $this->profile_id);
+                if (!$profile instanceof Profile) {
+                        throw new NoProfileException ($this->profile_id);
+                }
+                return $profile;
+        }
+
+        /**
+         * Generates an Activitypub_profile from a Profile
+         *
+         * @param Profile $profile
+         * @return Activitypub_profile
+         * @throws Exception if no Activitypub_profile exists for given Profile
+         */
+        static function fromProfile (Profile $profile)
+        {
+                $profile_id = $profile->getID ();
+
+                $aprofile = Activitypub_profile::getKV ('profile_id', $profile_id);
+                if (!$aprofile instanceof Activitypub_profile) {
+                        throw new Exception('No Activitypub_profile for Profile ID: '.$profile_id);
+                }
+
+                foreach ($profile as $key => $value) {
+                        $aprofile->$key = $value;
+                }
+
+                return $aprofile;
+        }
+
+        /**
+         * Returns sharedInbox if possible, inbox otherwise
+         *
+         * @return string Inbox URL
+         */
+        public function getInbox ()
+        {
+                if (is_null ($this->sharedInboxuri)) {
+                        return $this->inboxuri;
+                }
+
+                return $this->sharedInboxuri;
+        }
+}
--- a/classes/Activitypub_tag.php
+++ b/classes/Activitypub_tag.php
@ -0,0 +1,64 @@
+<?php
+/**
+ * GNU social - a federating social network
+ *
+ * ActivityPubPlugin implementation for GNU Social
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @copyright 2018 Free Software Foundation http://fsf.org
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      https://www.gnu.org/software/social/
+ */
+if (!defined ('GNUSOCIAL')) {
+        exit (1);
+}
+
+/**
+ * ActivityPub representation of a Tag
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      http://www.gnu.org/software/social/
+ */
+class Activitypub_tag extends Managed_DataObject
+{
+        /**
+         * Generates a pretty tag from a Tag object
+         *
+         * @param Tag $tag
+         * @return pretty array to be used in a response
+         */
+        public static function tag_to_array ($tag)
+        {
+                $res = [
+                '@context'          => [
+                "https://www.w3.org/ns/activitystreams",
+                [
+                  "@language" => "en"
+                ]
+                ],
+                'name' => $tag,
+                'url'  => common_local_url ('tag', array('tag' => $tag))
+                ];
+
+                return $res;
+        }
+}
--- a/utils/explorer.php
+++ b/utils/explorer.php
@ -0,0 +1,213 @@
+<?php
+/**
+ * GNU social - a federating social network
+ *
+ * ActivityPubPlugin implementation for GNU Social
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @copyright 2018 Free Software Foundation http://fsf.org
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      https://www.gnu.org/software/social/
+ */
+if (!defined ('GNUSOCIAL')) {
+        exit (1);
+}
+
+/**
+ * ActivityPub's own Explorer
+ *
+ * Allows to discovery new (or the same) ActivityPub profiles
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      http://www.gnu.org/software/social/
+ */
+class Activitypub_explorer
+{
+        private $discovered_actor_profiles = array ();
+
+        /**
+         * Get every profile from the given URL
+         * This function cleans the $this->discovered_actor_profiles array
+         * so that there is no erroneous data
+         *
+         * @param string $url User's url
+         * @return array of Profile objects
+         */
+        public function lookup ($url)
+        {
+                $this->discovered_actor_profiles = array ();
+
+                return $this->_lookup ($url);
+        }
+
+        /**
+         * Get every profile from the given URL
+         * This is a recursive function that will accumulate the results on
+         * $discovered_actor_profiles array
+         *
+         * @param string $url User's url
+         * @return array of Profile objects
+         */
+        private function _lookup ($url)
+        {
+                // First check if we already have it locally and, if so, return it
+                // If the local fetch fails: grab it remotely, store locally and return
+                if (! ($this->grab_local_user ($url) || $this->grab_remote_user ($url))) {
+                    throw new Exception ("User not found");
+                }
+
+
+                return $this->discovered_actor_profiles;
+        }
+
+        /**
+         * Get a local user profiles from its URL and joins it on
+         * $this->discovered_actor_profiles
+         *
+         * @param string $url User's url
+         * @return boolean success state
+         */
+        private function grab_local_user ($url)
+        {
+                if (($actor_profile = self::get_profile_by_url ($url)) != false) {
+                        $this->discovered_actor_profiles[]= $actor_profile;
+                        return true;
+                } else {
+                        /******************************** XXX: ********************************
+                         * Sometimes it is not true that the user is not locally available,   *
+                         * mostly when it is a local user and URLs slightly changed           *
+                         * e.g.: GS instance owner changed from standard urls to pretty urls  *
+                         * (not sure if this is necessary, but anyway)                        *
+                         **********************************************************************/
+
+                        // Iff we really are in the same instance
+                        $root_url_len = strlen (common_root_url ());
+                        if (substr ($url, 0, $root_url_len) == common_root_url ()) {
+                                // Grab the nickname and try to get the user
+                                if (($actor_profile = Profile::getKV ("nickname", substr ($url, $root_url_len))) != false) {
+                                        $this->discovered_actor_profiles[]= $actor_profile;
+                                        return true;
+                                }
+                        }
+                }
+                return false;
+        }
+
+        /**
+         * Get a remote user(s) profile(s) from its URL and joins it on
+         * $this->discovered_actor_profiles
+         *
+         * @param string $url User's url
+         * @return boolean success state
+         */
+        private function grab_remote_user ($url)
+        {
+                $client    = new HTTPClient ();
+                $headers   = array();
+                $headers[] = 'Accept: application/ld+json; profile="https://www.w3.org/ns/activitystreams"';
+                $headers[] = 'User-Agent: GNUSocialBot v0.1 - https://gnu.io/social';
+                $response  = $client->get ($url, $headers);
+                if (!$response->isOk ()) {
+                    throw new Exception ("Invalid Actor URL.");
+                }
+                $res = json_decode ($response->getBody (), JSON_UNESCAPED_SLASHES);
+                if (isset ($res["orderedItems"])) { // It's a potential collection of actors!!!
+                        foreach ($res["orderedItems"] as $profile) {
+                                if ($this->_lookup ($profile) == false) {
+                                        // XXX: Invalid actor found, not sure how we handle those
+                                }
+                        }
+                        // Go through entire collection
+                        if (!is_null ($res["next"])) {
+                                $this->_lookup ($res["next"]);
+                        }
+                        return true;
+                } else if ($this->validate_remote_response ($res)) {
+                        $this->discovered_actor_profiles[]= $this->store_profile ($res);
+                        return true;
+                }
+
+                return false;
+        }
+
+        /**
+         * Save remote user profile in local instance
+         *
+         * @param array $res remote response
+         * @return Profile remote Profile object
+         */
+        private function store_profile ($res)
+        {
+                $aprofile                 = new Activitypub_profile;
+                $aprofile->uri            = $res["url"];
+                $aprofile->nickname       = $res["nickname"];
+                $aprofile->fullname       = $res["display_name"];
+                $aprofile->bio            = substr ($res["summary"], 0, 1000);
+                $aprofile->inboxuri       = $res["inbox"];
+                $aprofile->sharedInboxuri = $res["sharedInbox"];
+
+                $aprofile->doInsert ();
+
+                return $aprofile->localProfile ();
+        }
+
+        /**
+         * Validates a remote response in order to determine whether this
+         * response is a valid profile or not
+         *
+         * @param array $res remote response
+         * @return boolean success state
+         */
+        private function validate_remote_response ($res)
+        {
+                if (!isset ($res["url"], $res["nickname"], $res["display_name"], $res["summary"], $res["inbox"], $res["sharedInbox"])) {
+                        return false;
+                }
+
+                return true;
+        }
+
+        /**
+         * Get a profile from it's profileurl
+         * Unfortunately GNU Social cache is not truly reliable when handling
+         * potential ActivityPub remote profiles, as so it is important to use
+         * this hacky workaround (at least for now)
+         *
+         * @param string $v URL
+         * @return boolean|Profile false if fails | Profile object if successful
+         */
+        static function get_profile_by_url ($v)
+        {
+                $i = Managed_DataObject::getcached(Profile, "profileurl", $v);
+                if (empty ($i)) { // false = cache miss
+                        $i = new Profile;
+                        $result = $i->get ("profileurl", $v);
+                        if ($result) {
+                                // Hit!
+                                $i->encache();
+                        } else {
+                            return false;
+                        }
+                }
+                return $i;
+        }
+}
--- a/utils/postman.php
+++ b/utils/postman.php
@ -0,0 +1,96 @@
+<?php
+/**
+ * GNU social - a federating social network
+ *
+ * ActivityPubPlugin implementation for GNU Social
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @author    Daniel Supernault <danielsupernault@gmail.com>
+ * @copyright 2018 Free Software Foundation http://fsf.org
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      https://www.gnu.org/software/social/
+ */
+if (!defined ('GNUSOCIAL')) {
+        exit (1);
+}
+
+/**
+ * ActivityPub's own Postman
+ *
+ * Standard workflow expects that we send an Explorer to find out destinataries'
+ * inbox address. Then we send our postman to deliver whatever we want to send them.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      http://www.gnu.org/software/social/
+ */
+class Activitypub_postman
+{
+        private $actor;
+        private $to = array ();
+        private $client;
+        private $headers;
+
+        /**
+         * Create a postman to deliver something to someone
+         *
+         * @param Activitypub_profile $to array of destinataries
+         */
+        public function __construct ($from, $to)
+        {
+                $this->actor = $from;
+                $this->to = $to;
+                $this->headers = array();
+                $this->headers[] = 'Accept: application/ld+json; profile="https://www.w3.org/ns/activitystreams"';
+                $this->headers[] = 'User-Agent: GNUSocialBot v0.1 - https://gnu.io/social';
+        }
+
+        /**
+         * Send a follow notification to remote instance
+         */
+        public function follow ()
+        {
+                $this->client = new HTTPClient ();
+                $data = array ("@context" => "https://www.w3.org/ns/activitystreams",
+                          "type"   => "Follow",
+                          "actor"  => $this->actor->getUrl (),
+                          "object" => $this->to[0]->getUrl ());
+                $this->client->setBody (json_encode ($data));
+                $response = $this->client->post ($this->to[0]->getInbox (), $this->headers);
+        }
+
+        /**
+         * Send a Undo Follow notification to remote instance
+         */
+        public function undo_follow ()
+        {
+                $this->client = new HTTPClient ();
+                $data = array ("@context" => "https://www.w3.org/ns/activitystreams",
+                            "type"   => "Undo",
+                            "actor"  => $this->actor->getUrl (),
+                            "object" => array (
+                                "type" => "Follow",
+                                "object" => $this->to[0]->getUrl ()
+                            )
+                        );
+                $this->client->setBody (json_encode ($data));
+                $response = $this->client->post ($this->to[0]->getInbox (), $this->headers);
+        }
+}
Author	SHA1	Message	Date
Diogo Cordeiro	27d62f1135	Skell for ActivityPub feed	2018-07-13 21:32:54 +01:00
Diogo Cordeiro	6a9b649cd7	Add classes description on docblock	2018-07-13 12:32:27 +01:00
Diogo Cordeiro	d7627fb061	Add Delivery Handler (named Postman) and Subscription hook Renamed Discovery to Explorer Various bug fixes and minor improvements	2018-07-13 00:52:12 +01:00
Diogo Cordeiro	542c269885	Fix following collection error message	2018-07-10 19:52:27 +01:00
Diogo Cordeiro	295d4a254d	Fix last merge issues	2018-07-10 02:08:06 +01:00
Diogo Cordeiro	ecb812d5e6	Merge branch 'feature-inbox' into 'dev' Add Feature inbox See merge request dansup/ActivityPub!7	2018-07-10 00:26:02 +00:00
Diogo Cordeiro	15fab762b5	Add Feature inbox	2018-07-10 00:26:02 +00:00
Diogo Cordeiro	08ec02561a	Add Discovery module See merge request dansup/ActivityPub!4	2018-07-09 23:19:07 +00:00
Diogo Cordeiro	cb70a8f6e8	Add and fix some code documentation	2018-07-10 00:17:18 +01:00
Diogo Cordeiro	fc5b344864	Add and fix some code documentation	2018-07-09 23:43:34 +01:00
Diogo Cordeiro	80b9d1873c	Improved Notice Entity	2018-07-09 20:07:35 +01:00
Diogo Cordeiro	cc69c33113	Now discovery module is able to go through collections	2018-07-09 14:41:53 +01:00
Diogo Cordeiro	f533ef2d32	Minor corrections	2018-07-09 00:07:14 +01:00
Diogo Cordeiro	7d773729b9	Merge branch 'return-handler' into 'dev' Add Return handler and plug it in the plugin See merge request dansup/ActivityPub!3	2018-07-08 22:58:16 +00:00
Diogo Cordeiro	167f88a602	We are not using laravel helpers on GNU Social	2018-07-06 21:52:03 +01:00
Diogo Cordeiro	4d3321ac21	Minor bug fix and workaround a potential GNU Social issue	2018-07-06 21:31:21 +01:00
Diogo Cordeiro	4cb1ed2c9d	Add discovery module	2018-07-06 12:16:09 +01:00
Diogo Cordeiro	c065c76f16	Add Return handler and plug it in the plugin	2018-07-06 11:57:39 +01:00
Diogo Cordeiro	67d52e1d13	Remove profile.json endpoint as it is double	2018-07-06 11:15:08 +01:00
Diogo Cordeiro	8d052e1d8c	Merge branch 'feature-following' into 'dev' Feature following See merge request dansup/ActivityPub!2	2018-05-13 14:09:38 +00:00
Diogo Cordeiro	2ef79cfad3	Fix issue #11	2018-05-13 15:07:02 +01:00
Diogo Cordeiro	395ca52eae	Implement Following	2018-05-10 23:57:43 +01:00
Diogo Cordeiro	370e2320a4	Added followers and following count on Profile entity	2018-05-10 16:26:22 +00:00
Diogo Cordeiro	bfc85fd485	Added followers and following count on Profile entitiy	2018-05-10 16:52:49 +01:00
Diogo Cordeiro	8480194479	Add implementation of Followers endpoint	2018-05-10 16:01:14 +01:00
Diogo Cordeiro	ea233925a8	Merge branch 'feature-like' into 'dev' Add Liked Collection See merge request dansup/ActivityPub!1	2018-05-05 23:31:35 +00:00
Diogo Cordeiro	35077111f4	Merge branch 'dev' into 'feature-like' # Conflicts: # ActivityPubPlugin.php # classes/Activitypub_attachment.php # classes/Activitypub_notice.php	2018-05-05 23:30:45 +00:00
Daniel Supernault	24e8b1579d	Add router overwrite method for actor responses	2018-05-05 17:25:02 -06:00
Diogo Cordeiro	81b9f17cb1	Query parameters implemented as per the doc Kept Attachment entity compatible with GS Master Fixed conversation id data type on Notice entity	2018-05-05 15:09:28 +01:00
Diogo Cordeiro	95fd0a75c4	Update endpoint URLs and lack of variable declaration fix	2018-05-05 01:32:27 +01:00
Diogo Cordeiro	3161b62b5d	Update per the master branch	2018-05-05 01:31:25 +01:00
Diogo Cordeiro	aea8915903	Update per the dev branch	2018-05-05 01:14:27 +01:00
Diogo Cordeiro	be73d6bdf6	Remove text_url which is no longer in the doc spec	2018-05-05 01:06:43 +01:00
Diogo Cordeiro	9c4dc1a233	New Entities added Moved "hard coded" profile from action to an Entity class Added the following entities: - Profile - Attachment - Notice - Tag	2018-05-05 00:54:41 +01:00
Diogo Cordeiro	4e431ee4a1	Follow the dev branch	2018-04-29 13:45:31 +01:00
Diogo Cordeiro	2889b1ba7e	Updated plugin as per the doc	2018-04-29 13:43:18 +01:00
Diogo Cordeiro	f2e98c1b73	README	2018-04-29 13:38:14 +01:00
Diogo Cordeiro	0938e7809f	Updated the plugin as per the doc TODO: Implement query parameters in apactorlikedcollection.php" as per the doc	2018-04-29 13:23:54 +01:00
Diogo Cordeiro	21abaca924	README	2018-04-29 02:54:07 +01:00
Diogo Cordeiro	16dcfe522d	First draft of Liked Collection	2018-04-29 01:10:54 +01:00
Diogo Cordeiro	8efcc5742d	Default Avatar URL is now returned	2018-04-28 20:59:47 +01:00
Daniel Supernault	dbeb3d0ce7	Catch NoAvatarException	2018-03-25 17:46:41 -06:00
Daniel Supernault	6a3e9a6df1	Add icon property to Actor action	2018-03-25 17:39:24 -06:00
Daniel Supernault	839e1f01af	Add following/followers to ActivityPubActor action	2018-03-25 14:55:14 -06:00
Daniel Supernault	d44a5974da	Update ActivityPubActor action	2018-03-25 14:45:00 -06:00
Daniel Supernault	80bf4c1219	Update ActivityPubActor action	2018-03-25 14:43:06 -06:00
Daniel Supernault	cc454c2a37	Add base plugin and the beginning of the actor method	2018-03-25 14:16:43 -06:00