src/Module/Objects.php

   1 <?php
   2 /**
   3  * @copyright Copyright (C) 2020, Friendica
   4  *
   5  * @license GNU AGPL version 3 or any later version
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU Affero General Public License as
   9  * published by the Free Software Foundation, either version 3 of the
  10  * License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU Affero General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Affero General Public License
  18  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  19  *
  20  */
  21
  22 namespace Friendica\Module;
  23
  24 use Friendica\BaseModule;
  25 use Friendica\Core\System;
  26 use Friendica\Database\DBA;
  27 use Friendica\DI;
  28 use Friendica\Model\Item;
  29 use Friendica\Network\HTTPException;
  30 use Friendica\Protocol\ActivityPub;
  31 use Friendica\Util\Network;
  32
  33 /**
  34  * ActivityPub Objects
  35  */
  36 class Objects extends BaseModule
  37 {
  38         public static function rawContent(array $parameters = [])
  39         {
  40                 if (empty($parameters['guid'])) {
  41                         throw new HTTPException\BadRequestException();
  42                 }
  43
  44                 if (!ActivityPub::isRequest()) {
  45                         DI::baseUrl()->redirect(str_replace('objects/', 'display/', DI::args()->getQueryString()));
  46                 }
  47
  48                 /// @todo Add Authentication to enable fetching of non public content
  49                 // $requester = HTTPSignature::getSigner('', $_SERVER);
  50
  51                 $item = Item::selectFirst(
  52                         ['id', 'origin', 'author-link', 'changed'],
  53                         [
  54                                 'guid' => $parameters['guid'],
  55                                 'private' => [Item::PUBLIC, Item::UNLISTED]
  56                         ],
  57                         ['order' => ['origin' => true]]
  58                 );
  59                 // Valid items are original post or posted from this node (including in the case of a forum)
  60                 if (!DBA::isResult($item) || !$item['origin'] && (parse_url($item['author-link'], PHP_URL_HOST) != parse_url(DI::baseUrl()->get(), PHP_URL_HOST))) {
  61                         throw new HTTPException\NotFoundException();
  62                 }
  63
  64                 $etag          = md5($parameters['guid'] . '-' . $item['changed']);
  65                 $last_modified = $item['changed'];
  66                 Network::checkEtagModified($etag, $last_modified);
  67
  68                 if (empty($parameters['activity'])) {
  69                         $activity = ActivityPub\Transmitter::createActivityFromItem($item['id'], true);
  70                         $activity['type'] = $activity['type'] == 'Update' ? 'Create' : $activity['type'];
  71
  72                         // Only display "Create" activity objects here, no reshares or anything else
  73                         if (empty($activity['object']) || ($activity['type'] != 'Create')) {
  74                                 throw new HTTPException\NotFoundException();
  75                         }
  76
  77                         $data = ['@context' => ActivityPub::CONTEXT];
  78                         $data = array_merge($data, $activity['object']);
  79                 } elseif (in_array($parameters['activity'], ['Create', 'Announce', 'Update',
  80                         'Like', 'Dislike', 'Accept', 'Reject', 'TentativeAccept', 'Follow', 'Add'])) {
  81                         $data = ActivityPub\Transmitter::createActivityFromItem($item['id']);
  82                         if (empty($data)) {
  83                                 throw new HTTPException\NotFoundException();
  84                         }
  85                         if ($parameters['activity'] != 'Create') {
  86                                 $data['type'] = $parameters['activity'];
  87                                 $data['id'] = str_replace('/Create', '/' . $parameters['activity'], $data['id']);
  88                         }
  89                 } else {
  90                         throw new HTTPException\NotFoundException();
  91                 }
  92
  93                 // Relaxed CORS header for public items
  94                 header('Access-Control-Allow-Origin: *');
  95                 System::jsonExit($data, 'application/activity+json');
  96         }
  97 }