gnu-social/plugins/ActivityPub/lib/models/Activitypub_announce.php

<?php
// This file is part of GNU social - https://www.gnu.org/software/social
//
// GNU social 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.
//
// GNU social 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 GNU social.  If not, see <http://www.gnu.org/licenses/>.

/**
 * ActivityPub implementation for GNU social
 *
 * @package   GNUsocial
 * @author    Diogo Cordeiro <diogo@fc.up.pt>
 * @copyright 2018-2019 Free Software Foundation, Inc http://www.fsf.org
 * @license   https://www.gnu.org/licenses/agpl.html GNU AGPL v3 or later
 * @link      http://www.gnu.org/software/social/
 */

defined('GNUSOCIAL') || die();

/**
 * ActivityPub error representation
 *
 * @category  Plugin
 * @package   GNUsocial
 * @author    Diogo Cordeiro <diogo@fc.up.pt>
 * @license   https://www.gnu.org/licenses/agpl.html GNU AGPL v3 or later
 */
class Activitypub_announce
{
    /**
     * Generates an ActivityPub representation of a Announce
     *
     * @param Profile $actor
     * @param Notice $notice
     * @return array pretty array to be used in a response
     * @author Diogo Cordeiro <diogo@fc.up.pt>
     */
    public static function announce_to_array(Profile $actor, Notice $notice): array
    {
        $actor_uri = ActivityPubPlugin::actor_uri($actor);
        $notice_url = Activitypub_notice::getUrl($notice);

        $to = [common_local_url('apActorFollowers', ['id' => $actor->getID()])];
        foreach ($notice->getAttentionProfiles() as $to_profile) {
            $to[] = $to_profile->getUri();
        }

        $cc[]= 'https://www.w3.org/ns/activitystreams#Public';

        $res = [
            '@context' => 'https://www.w3.org/ns/activitystreams',
            'id'     => common_root_url().'share_from_'.urlencode($actor_uri).'_to_'.urlencode($notice_url),
            "type"   => "Announce",
            "actor"  => $actor_uri,
            "object" => $notice_url,
            "to"     => $to,
            "cc"     => $cc
        ];
        return $res;
    }
}