src/Protocol/ActivityPub/Receiver.php

   1 <?php
   2 /**
   3  * @file src/Protocol/ActivityPub/Receiver.php
   4  */
   5 namespace Friendica\Protocol\ActivityPub;
   6
   7 use Friendica\Database\DBA;
   8 use Friendica\Util\HTTPSignature;
   9 use Friendica\Core\Protocol;
  10 use Friendica\Model\Contact;
  11 use Friendica\Model\APContact;
  12 use Friendica\Model\Item;
  13 use Friendica\Model\User;
  14 use Friendica\Util\JsonLD;
  15 use Friendica\Util\LDSignature;
  16 use Friendica\Protocol\ActivityPub;
  17
  18 /**
  19  * @brief ActivityPub Receiver Protocol class
  20  *
  21  * To-Do:
  22  * - Update (Image, Video, Article, Note)
  23  * - Event
  24  * - Undo Announce
  25  *
  26  * Check what this is meant to do:
  27  * - Add
  28  * - Block
  29  * - Flag
  30  * - Remove
  31  * - Undo Block
  32  * - Undo Accept (Problem: This could invert a contact accept or an event accept)
  33  *
  34  * General:
  35  * - Possibly using the LD-JSON parser
  36  */
  37 class Receiver
  38 {
  39         const PUBLIC_COLLECTION = 'as:Public';
  40         const ACCOUNT_TYPES = ['as:Person', 'as:Organization', 'as:Service', 'as:Group', 'as:Application'];
  41         const CONTENT_TYPES = ['as:Note', 'as:Article', 'as:Video', 'as:Image'];
  42         const ACTIVITY_TYPES = ['as:Like', 'as:Dislike', 'as:Accept', 'as:Reject', 'as:TentativeAccept'];
  43
  44         /**
  45          * Checks if the web request is done for the AP protocol
  46          *
  47          * @return is it AP?
  48          */
  49         public static function isRequest()
  50         {
  51                 return stristr(defaults($_SERVER, 'HTTP_ACCEPT', ''), 'application/activity+json') ||
  52                         stristr(defaults($_SERVER, 'HTTP_ACCEPT', ''), 'application/ld+json');
  53         }
  54
  55         /**
  56          * Checks incoming message from the inbox
  57          *
  58          * @param $body
  59          * @param $header
  60          * @param integer $uid User ID
  61          */
  62         public static function processInbox($body, $header, $uid)
  63         {
  64                 $http_signer = HTTPSignature::getSigner($body, $header);
  65                 if (empty($http_signer)) {
  66                         logger('Invalid HTTP signature, message will be discarded.', LOGGER_DEBUG);
  67                         return;
  68                 } else {
  69                         logger('HTTP signature is signed by ' . $http_signer, LOGGER_DEBUG);
  70                 }
  71
  72                 $activity = json_decode($body, true);
  73
  74                 if (empty($activity)) {
  75                         logger('Invalid body.', LOGGER_DEBUG);
  76                         return;
  77                 }
  78
  79                 $ldactivity = JsonLD::compact($activity);
  80
  81                 $actor = JsonLD::fetchElement($ldactivity, 'as:actor');
  82
  83                 logger('Message for user ' . $uid . ' is from actor ' . $actor, LOGGER_DEBUG);
  84
  85                 if (LDSignature::isSigned($activity)) {
  86                         $ld_signer = LDSignature::getSigner($activity);
  87                         if (empty($ld_signer)) {
  88                                 logger('Invalid JSON-LD signature from ' . $actor, LOGGER_DEBUG);
  89                         }
  90                         if (!empty($ld_signer && ($actor == $http_signer))) {
  91                                 logger('The HTTP and the JSON-LD signature belong to ' . $ld_signer, LOGGER_DEBUG);
  92                                 $trust_source = true;
  93                         } elseif (!empty($ld_signer)) {
  94                                 logger('JSON-LD signature is signed by ' . $ld_signer, LOGGER_DEBUG);
  95                                 $trust_source = true;
  96                         } elseif ($actor == $http_signer) {
  97                                 logger('Bad JSON-LD signature, but HTTP signer fits the actor.', LOGGER_DEBUG);
  98                                 $trust_source = true;
  99                         } else {
 100                                 logger('Invalid JSON-LD signature and the HTTP signer is different.', LOGGER_DEBUG);
 101                                 $trust_source = false;
 102                         }
 103                 } elseif ($actor == $http_signer) {
 104                         logger('Trusting post without JSON-LD signature, The actor fits the HTTP signer.', LOGGER_DEBUG);
 105                         $trust_source = true;
 106                 } else {
 107                         logger('No JSON-LD signature, different actor.', LOGGER_DEBUG);
 108                         $trust_source = false;
 109                 }
 110
 111                 self::processActivity($ldactivity, $body, $uid, $trust_source);
 112         }
 113
 114         /**
 115          * Prepare the object array
 116          *
 117          * @param array $activity
 118          * @param integer $uid User ID
 119          * @param $trust_source
 120          *
 121          * @return array with object data
 122          */
 123         private static function prepareObjectData($activity, $uid, &$trust_source)
 124         {
 125                 $actor = JsonLD::fetchElement($activity, 'as:actor');
 126                 if (empty($actor)) {
 127                         logger('Empty actor', LOGGER_DEBUG);
 128                         return [];
 129                 }
 130
 131                 $type = JsonLD::fetchElement($activity, '@type');
 132
 133                 // Fetch all receivers from to, cc, bto and bcc
 134                 $receivers = self::getReceivers($activity, $actor);
 135
 136                 // When it is a delivery to a personal inbox we add that user to the receivers
 137                 if (!empty($uid)) {
 138                         $owner = User::getOwnerDataById($uid);
 139                         $additional = ['uid:' . $uid => $uid];
 140                         $receivers = array_merge($receivers, $additional);
 141                 }
 142
 143                 logger('Receivers: ' . json_encode($receivers), LOGGER_DEBUG);
 144
 145                 $object_id = JsonLD::fetchElement($activity, 'as:object');
 146                 if (empty($object_id)) {
 147                         logger('No object found', LOGGER_DEBUG);
 148                         return [];
 149                 }
 150
 151                 // Fetch the content only on activities where this matters
 152                 if (in_array($type, ['as:Create', 'as:Announce'])) {
 153                         if ($type == 'as:Announce') {
 154                                 $trust_source = false;
 155                         }
 156                         $object_data = self::fetchObject($object_id, $activity['as:object'], $trust_source);
 157                         if (empty($object_data)) {
 158                                 logger("Object data couldn't be processed", LOGGER_DEBUG);
 159                                 return [];
 160                         }
 161                         // We had been able to retrieve the object data - so we can trust the source
 162                         $trust_source = true;
 163                 } elseif (in_array($type, ['as:Like', 'as:Dislike'])) {
 164                         // Create a mostly empty array out of the activity data (instead of the object).
 165                         // This way we later don't have to check for the existence of ech individual array element.
 166                         $object_data = self::processObject($activity);
 167                         $object_data['name'] = $type;
 168                         $object_data['author'] = JsonLD::fetchElement($activity, 'as:actor');
 169                         $object_data['object_id'] = $object_id;
 170                         $object_data['object_type'] = ''; // Since we don't fetch the object, we don't know the type
 171                 } else {
 172                         $object_data = [];
 173                         $object_data['id'] = JsonLD::fetchElement($activity, '@id');
 174                         $object_data['object_id'] = JsonLD::fetchElement($activity, 'as:object');
 175                         $object_data['object_actor'] = JsonLD::fetchElement($activity['as:object'], 'as:actor');
 176                         $object_data['object_object'] = JsonLD::fetchElement($activity['as:object'], 'as:object');
 177                         $object_data['object_type'] = JsonLD::fetchElement($activity['as:object'], '@type');
 178                 }
 179
 180                 $object_data = self::addActivityFields($object_data, $activity);
 181
 182                 $object_data['type'] = $type;
 183                 $object_data['actor'] = $actor;
 184                 $object_data['receiver'] = array_merge(defaults($object_data, 'receiver', []), $receivers);
 185
 186                 logger('Processing ' . $object_data['type'] . ' ' . $object_data['object_type'] . ' ' . $object_data['id'], LOGGER_DEBUG);
 187
 188                 return $object_data;
 189         }
 190
 191         /**
 192          * Processes the activity object
 193          *
 194          * @param array   $activity     Array with activity data
 195          * @param string  $body
 196          * @param integer $uid          User ID
 197          * @param boolean $trust_source Do we trust the source?
 198          */
 199         public static function processActivity($activity, $body = '', $uid = null, $trust_source = false)
 200         {
 201                 $type = JsonLD::fetchElement($activity, '@type');
 202                 if (!$type) {
 203                         logger('Empty type', LOGGER_DEBUG);
 204                         return;
 205                 }
 206
 207                 if (!JsonLD::fetchElement($activity, 'as:object')) {
 208                         logger('Empty object', LOGGER_DEBUG);
 209                         return;
 210                 }
 211
 212                 if (!JsonLD::fetchElement($activity, 'as:actor')) {
 213                         logger('Empty actor', LOGGER_DEBUG);
 214                         return;
 215
 216                 }
 217
 218                 // $trust_source is called by reference and is set to true if the content was retrieved successfully
 219                 $object_data = self::prepareObjectData($activity, $uid, $trust_source);
 220                 if (empty($object_data)) {
 221                         logger('No object data found', LOGGER_DEBUG);
 222                         return;
 223                 }
 224
 225                 if (!$trust_source) {
 226                         logger('No trust for activity type "' . $type . '", so we quit now.', LOGGER_DEBUG);
 227                         return;
 228                 }
 229
 230                 switch ($type) {
 231                         case 'as:Create':
 232                         case 'as:Announce':
 233                                 ActivityPub\Processor::createItem($object_data, $body);
 234                                 break;
 235
 236                         case 'as:Like':
 237                                 ActivityPub\Processor::likeItem($object_data, $body);
 238                                 break;
 239
 240                         case 'as:Dislike':
 241                                 ActivityPub\Processor::dislikeItem($object_data, $body);
 242                                 break;
 243
 244                         case 'as:Update':
 245                                 if (in_array($object_data['object_type'], self::CONTENT_TYPES)) {
 246                                         /// @todo
 247                                 } elseif (in_array($object_data['object_type'], self::ACCOUNT_TYPES)) {
 248                                         ActivityPub\Processor::updatePerson($object_data, $body);
 249                                 }
 250                                 break;
 251
 252                         case 'as:Delete':
 253                                 if ($object_data['object_type'] == 'as:Tombstone') {
 254                                         ActivityPub\Processor::deleteItem($object_data, $body);
 255                                 } elseif (in_array($object_data['object_type'], self::ACCOUNT_TYPES)) {
 256                                         ActivityPub\Processor::deletePerson($object_data, $body);
 257                                 }
 258                                 break;
 259
 260                         case 'as:Follow':
 261                                 ActivityPub\Processor::followUser($object_data);
 262                                 break;
 263
 264                         case 'as:Accept':
 265                                 if ($object_data['object_type'] == 'as:Follow') {
 266                                         ActivityPub\Processor::acceptFollowUser($object_data);
 267                                 }
 268                                 break;
 269
 270                         case 'as:Reject':
 271                                 if ($object_data['object_type'] == 'as:Follow') {
 272                                         ActivityPub\Processor::rejectFollowUser($object_data);
 273                                 }
 274                                 break;
 275
 276                         case 'as:Undo':
 277                                 if ($object_data['object_type'] == 'as:Follow') {
 278                                         ActivityPub\Processor::undoFollowUser($object_data);
 279                                 } elseif (in_array($object_data['object_type'], self::ACTIVITY_TYPES)) {
 280                                         ActivityPub\Processor::undoActivity($object_data);
 281                                 }
 282                                 break;
 283
 284                         default:
 285                                 logger('Unknown activity: ' . $type, LOGGER_DEBUG);
 286                                 break;
 287                 }
 288         }
 289
 290         /**
 291          * Fetch the receiver list from an activity array
 292          *
 293          * @param array $activity
 294          * @param string $actor
 295          *
 296          * @return array with receivers (user id)
 297          */
 298         private static function getReceivers($activity, $actor)
 299         {
 300                 $receivers = [];
 301
 302                 // When it is an answer, we inherite the receivers from the parent
 303                 $replyto = JsonLD::fetchElement($activity, 'as:inReplyTo');
 304                 if (!empty($replyto)) {
 305                         $parents = Item::select(['uid'], ['uri' => $replyto]);
 306                         while ($parent = Item::fetch($parents)) {
 307                                 $receivers['uid:' . $parent['uid']] = $parent['uid'];
 308                         }
 309                 }
 310
 311                 if (!empty($actor)) {
 312                         $profile = APContact::getByURL($actor);
 313                         $followers = defaults($profile, 'followers', '');
 314
 315                         logger('Actor: ' . $actor . ' - Followers: ' . $followers, LOGGER_DEBUG);
 316                 } else {
 317                         logger('Empty actor', LOGGER_DEBUG);
 318                         $followers = '';
 319                 }
 320
 321                 foreach (['as:to', 'as:cc', 'as:bto', 'as:bcc'] as $element) {
 322                         $receiver_list = JsonLD::fetchElementArray($activity, $element);
 323                         if (empty($receiver_list)) {
 324                                 continue;
 325                         }
 326
 327                         foreach ($receiver_list as $receiver) {
 328                                 if ($receiver == self::PUBLIC_COLLECTION) {
 329                                         $receivers['uid:0'] = 0;
 330                                 }
 331
 332                                 if (($receiver == self::PUBLIC_COLLECTION) && !empty($actor)) {
 333                                         // This will most likely catch all OStatus connections to Mastodon
 334                                         $condition = ['alias' => [$actor, normalise_link($actor)], 'rel' => [Contact::SHARING, Contact::FRIEND]
 335                                                 , 'archive' => false, 'pending' => false];
 336                                         $contacts = DBA::select('contact', ['uid'], $condition);
 337                                         while ($contact = DBA::fetch($contacts)) {
 338                                                 if ($contact['uid'] != 0) {
 339                                                         $receivers['uid:' . $contact['uid']] = $contact['uid'];
 340                                                 }
 341                                         }
 342                                         DBA::close($contacts);
 343                                 }
 344
 345                                 if (in_array($receiver, [$followers, self::PUBLIC_COLLECTION]) && !empty($actor)) {
 346                                         $condition = ['nurl' => normalise_link($actor), 'rel' => [Contact::SHARING, Contact::FRIEND],
 347                                                 'network' => Protocol::ACTIVITYPUB, 'archive' => false, 'pending' => false];
 348                                         $contacts = DBA::select('contact', ['uid'], $condition);
 349                                         while ($contact = DBA::fetch($contacts)) {
 350                                                 if ($contact['uid'] != 0) {
 351                                                         $receivers['uid:' . $contact['uid']] = $contact['uid'];
 352                                                 }
 353                                         }
 354                                         DBA::close($contacts);
 355                                         continue;
 356                                 }
 357
 358                                 $condition = ['self' => true, 'nurl' => normalise_link($receiver)];
 359                                 $contact = DBA::selectFirst('contact', ['uid'], $condition);
 360                                 if (!DBA::isResult($contact)) {
 361                                         continue;
 362                                 }
 363                                 $receivers['uid:' . $contact['uid']] = $contact['uid'];
 364                         }
 365                 }
 366
 367                 self::switchContacts($receivers, $actor);
 368
 369                 return $receivers;
 370         }
 371
 372         /**
 373          * Switches existing contacts to ActivityPub
 374          *
 375          * @param integer $cid Contact ID
 376          * @param integer $uid User ID
 377          * @param string $url Profile URL
 378          */
 379         private static function switchContact($cid, $uid, $url)
 380         {
 381                 $profile = ActivityPub::probeProfile($url);
 382                 if (empty($profile)) {
 383                         return;
 384                 }
 385
 386                 logger('Switch contact ' . $cid . ' (' . $profile['url'] . ') for user ' . $uid . ' to ActivityPub');
 387
 388                 $photo = $profile['photo'];
 389                 unset($profile['photo']);
 390                 unset($profile['baseurl']);
 391
 392                 $profile['nurl'] = normalise_link($profile['url']);
 393                 DBA::update('contact', $profile, ['id' => $cid]);
 394
 395                 Contact::updateAvatar($photo, $uid, $cid);
 396
 397                 // Send a new follow request to be sure that the connection still exists
 398                 if (($uid != 0) && DBA::exists('contact', ['id' => $cid, 'rel' => [Contact::SHARING, Contact::FRIEND]])) {
 399                         ActivityPub\Transmitter::sendActivity('Follow', $profile['url'], $uid);
 400                         logger('Send a new follow request to ' . $profile['url'] . ' for user ' . $uid, LOGGER_DEBUG);
 401                 }
 402         }
 403
 404         /**
 405          *
 406          *
 407          * @param $receivers
 408          * @param $actor
 409          */
 410         private static function switchContacts($receivers, $actor)
 411         {
 412                 if (empty($actor)) {
 413                         return;
 414                 }
 415
 416                 foreach ($receivers as $receiver) {
 417                         $contact = DBA::selectFirst('contact', ['id'], ['uid' => $receiver, 'network' => Protocol::OSTATUS, 'nurl' => normalise_link($actor)]);
 418                         if (DBA::isResult($contact)) {
 419                                 self::switchContact($contact['id'], $receiver, $actor);
 420                         }
 421
 422                         $contact = DBA::selectFirst('contact', ['id'], ['uid' => $receiver, 'network' => Protocol::OSTATUS, 'alias' => [normalise_link($actor), $actor]]);
 423                         if (DBA::isResult($contact)) {
 424                                 self::switchContact($contact['id'], $receiver, $actor);
 425                         }
 426                 }
 427         }
 428
 429         /**
 430          *
 431          *
 432          * @param $object_data
 433          * @param array $activity
 434          *
 435          * @return
 436          */
 437         private static function addActivityFields($object_data, $activity)
 438         {
 439                 if (!empty($activity['published']) && empty($object_data['published'])) {
 440                         $object_data['published'] = JsonLD::fetchElement($activity, 'published', '@value');
 441                 }
 442
 443                 if (!empty($activity['updated']) && empty($object_data['updated'])) {
 444                         $object_data['updated'] = JsonLD::fetchElement($activity, 'updated', '@value');
 445                 }
 446
 447                 if (!empty($activity['diaspora:guid']) && empty($object_data['diaspora:guid'])) {
 448                         $object_data['diaspora:guid'] = JsonLD::fetchElement($activity, 'diaspora:guid');
 449                 }
 450
 451                 if (!empty($activity['inReplyTo']) && empty($object_data['parent-uri'])) {
 452                         $object_data['parent-uri'] = JsonLD::fetchElement($activity, 'inReplyTo');
 453                 }
 454
 455                 if (!empty($activity['instrument'])) {
 456                         $object_data['service'] = JsonLD::fetchElement($activity, 'instrument', 'name', 'type', 'Service');
 457                 }
 458                 return $object_data;
 459         }
 460
 461         /**
 462          * Fetches the object data from external ressources if needed
 463          *
 464          * @param string  $object_id    Object ID of the the provided object
 465          * @param array   $object       The provided object array
 466          * @param boolean $trust_source Do we trust the provided object?
 467          *
 468          * @return array with trusted and valid object data
 469          */
 470         private static function fetchObject($object_id, $object = [], $trust_source = false)
 471         {
 472                 // By fetching the type we check if the object is complete.
 473                 $type = JsonLD::fetchElement($object, '@type');
 474
 475                 if (!$trust_source || empty($type)) {
 476                         $data = ActivityPub::fetchContent($object_id);
 477                         if (!empty($data)) {
 478                                 $object = JsonLD::compact($data);
 479                                 logger('Fetched content for ' . $object_id, LOGGER_DEBUG);
 480                         } else {
 481                                 logger('Empty content for ' . $object_id . ', check if content is available locally.', LOGGER_DEBUG);
 482
 483                                 $item = Item::selectFirst([], ['uri' => $object_id]);
 484                                 if (!DBA::isResult($item)) {
 485                                         logger('Object with url ' . $object_id . ' was not found locally.', LOGGER_DEBUG);
 486                                         return false;
 487                                 }
 488                                 logger('Using already stored item for url ' . $object_id, LOGGER_DEBUG);
 489                                 $data = ActivityPub\Transmitter::createNote($item);
 490                                 $object = JsonLD::compact($data);
 491                         }
 492                 } else {
 493                         logger('Using original object for url ' . $object_id, LOGGER_DEBUG);
 494                 }
 495
 496                 $type = JsonLD::fetchElement($object, '@type');
 497
 498                 if (empty($type)) {
 499                         logger('Empty type', LOGGER_DEBUG);
 500                         return false;
 501                 }
 502
 503                 if (in_array($type, self::CONTENT_TYPES)) {
 504                         return self::processObject($object);
 505                 }
 506
 507                 if ($type == 'as:Announce') {
 508                         $object_id = JsonLD::fetchElement($object, 'object');
 509                         if (empty($object_id)) {
 510                                 return false;
 511                         }
 512                         return self::fetchObject($object_id);
 513                 }
 514
 515                 logger('Unhandled object type: ' . $type, LOGGER_DEBUG);
 516         }
 517
 518         /**
 519          * Convert tags from JSON-LD format into a simplified format
 520          *
 521          * @param array $tags Tags in JSON-LD format
 522          *
 523          * @return array with tags in a simplified format
 524          */
 525         private static function processTags($tags)
 526         {
 527                 $taglist = [];
 528
 529                 if (empty($tags)) {
 530                         return [];
 531                 }
 532
 533                 foreach ($tags as $tag) {
 534                         if (empty($tag)) {
 535                                 continue;
 536                         }
 537
 538                         $taglist[] = ['type' => str_replace('as:', '', JsonLD::fetchElement($tag, '@type')),
 539                                 'href' => JsonLD::fetchElement($tag, 'as:href'),
 540                                 'name' => JsonLD::fetchElement($tag, 'as:name')];
 541                 }
 542                 return $taglist;
 543         }
 544
 545         /**
 546          * Convert attachments from JSON-LD format into a simplified format
 547          *
 548          * @param array $attachments Attachments in JSON-LD format
 549          *
 550          * @return array with attachmants in a simplified format
 551          */
 552         private static function processAttachments($attachments)
 553         {
 554                 $attachlist = [];
 555
 556                 if (empty($attachments)) {
 557                         return [];
 558                 }
 559
 560                 foreach ($attachments as $attachment) {
 561                         if (empty($attachment)) {
 562                                 continue;
 563                         }
 564
 565                         $attachlist[] = ['type' => str_replace('as:', '', JsonLD::fetchElement($attachment, '@type')),
 566                                 'mediaType' => JsonLD::fetchElement($attachment, 'as:mediaType'),
 567                                 'name' => JsonLD::fetchElement($attachment, 'as:name'),
 568                                 'url' => JsonLD::fetchElement($attachment, 'as:url')];
 569                 }
 570                 return $attachlist;
 571         }
 572
 573         /**
 574          * Fetches data from the object part of an activity
 575          *
 576          * @param array $object
 577          *
 578          * @return array
 579          */
 580         private static function processObject($object)
 581         {
 582                 if (!JsonLD::fetchElement($object, '@id')) {
 583                         return false;
 584                 }
 585
 586                 $object_data = [];
 587                 $object_data['object_type'] = JsonLD::fetchElement($object, '@type');
 588                 $object_data['id'] = JsonLD::fetchElement($object, '@id');
 589
 590                 $object_data['reply-to-id'] = JsonLD::fetchElement($object, 'as:inReplyTo');
 591
 592                 if (empty($object_data['reply-to-id'])) {
 593                         $object_data['reply-to-id'] = $object_data['id'];
 594                 }
 595
 596                 $object_data['published'] = JsonLD::fetchElement($object, 'as:published', '@value');
 597                 $object_data['updated'] = JsonLD::fetchElement($object, 'as:updated', '@value');
 598
 599                 if (empty($object_data['updated'])) {
 600                         $object_data['updated'] = $object_data['published'];
 601                 }
 602
 603                 if (empty($object_data['published']) && !empty($object_data['updated'])) {
 604                         $object_data['published'] = $object_data['updated'];
 605                 }
 606
 607                 $actor = JsonLD::fetchElement($object, 'as:attributedTo');
 608                 if (empty($actor)) {
 609                         $actor = JsonLD::fetchElement($object, 'as:actor');
 610                 }
 611
 612                 $object_data['diaspora:guid'] = JsonLD::fetchElement($object, 'diaspora:guid');
 613                 $object_data['diaspora:comment'] = JsonLD::fetchElement($object, 'diaspora:comment');
 614                 $object_data['actor'] = $object_data['author'] = $actor;
 615                 $object_data['context'] = JsonLD::fetchElement($object, 'as:context');
 616                 $object_data['conversation'] = JsonLD::fetchElement($object, 'ostatus:conversation');
 617                 $object_data['sensitive'] = JsonLD::fetchElement($object, 'as:sensitive');
 618                 $object_data['name'] = JsonLD::fetchElement($object, 'as:name');
 619                 $object_data['summary'] = JsonLD::fetchElement($object, 'as:summary');
 620                 $object_data['content'] = JsonLD::fetchElement($object, 'as:content');
 621                 $object_data['source'] = JsonLD::fetchElement($object, 'as:source', 'as:content', 'as:mediaType', 'text/bbcode');
 622                 $object_data['location'] = JsonLD::fetchElement($object, 'as:location', 'as:name', '@type', 'as:Place');
 623                 $object_data['attachments'] = self::processAttachments(JsonLD::fetchElementArray($object, 'as:attachment'));
 624                 $object_data['tags'] = self::processTags(JsonLD::fetchElementArray($object, 'as:tag'));
 625 //              $object_data['service'] = JsonLD::fetchElement($object, 'instrument', 'name', 'type', 'Service'); // todo
 626                 $object_data['service'] = null;
 627                 $object_data['alternate-url'] = JsonLD::fetchElement($object, 'as:url');
 628
 629                 // Special treatment for Hubzilla links
 630                 if (is_array($object_data['alternate-url'])) {
 631                         if (!empty($object['as:url'])) {
 632                                 $object_data['alternate-url'] = JsonLD::fetchElement($object['as:url'], 'as:href');
 633                         } else {
 634                                 $object_data['alternate-url'] = null;
 635                         }
 636                 }
 637
 638                 $object_data['receiver'] = self::getReceivers($object, $object_data['actor']);
 639
 640                 // Common object data:
 641
 642                 // Unhandled
 643                 // @context, type, actor, signature, mediaType, duration, replies, icon
 644
 645                 // Also missing: (Defined in the standard, but currently unused)
 646                 // audience, preview, endTime, startTime, generator, image
 647
 648                 // Data in Notes:
 649
 650                 // Unhandled
 651                 // contentMap, announcement_count, announcements, context_id, likes, like_count
 652                 // inReplyToStatusId, shares, quoteUrl, statusnetConversationId
 653
 654                 // Data in video:
 655
 656                 // To-Do?
 657                 // category, licence, language, commentsEnabled
 658
 659                 // Unhandled
 660                 // views, waitTranscoding, state, support, subtitleLanguage
 661                 // likes, dislikes, shares, comments
 662
 663                 return $object_data;
 664         }
 665 }