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\Logger;
  10 use Friendica\Core\Protocol;
  11 use Friendica\Model\Contact;
  12 use Friendica\Model\APContact;
  13 use Friendica\Model\Item;
  14 use Friendica\Model\User;
  15 use Friendica\Util\JsonLD;
  16 use Friendica\Util\LDSignature;
  17 use Friendica\Protocol\ActivityPub;
  18 use Friendica\Model\Conversation;
  19 use Friendica\Util\DateTimeFormat;
  20
  21 /**
  22  * @brief ActivityPub Receiver Protocol class
  23  *
  24  * To-Do:
  25  * - Undo Announce
  26  *
  27  * Check what this is meant to do:
  28  * - Add
  29  * - Block
  30  * - Flag
  31  * - Remove
  32  * - Undo Block
  33  */
  34 class Receiver
  35 {
  36         const PUBLIC_COLLECTION = 'as:Public';
  37         const ACCOUNT_TYPES = ['as:Person', 'as:Organization', 'as:Service', 'as:Group', 'as:Application'];
  38         const CONTENT_TYPES = ['as:Note', 'as:Article', 'as:Video', 'as:Image', 'as:Event'];
  39         const ACTIVITY_TYPES = ['as:Like', 'as:Dislike', 'as:Accept', 'as:Reject', 'as:TentativeAccept'];
  40
  41         /**
  42          * Checks if the web request is done for the AP protocol
  43          *
  44          * @return is it AP?
  45          */
  46         public static function isRequest()
  47         {
  48                 return stristr(defaults($_SERVER, 'HTTP_ACCEPT', ''), 'application/activity+json') ||
  49                         stristr(defaults($_SERVER, 'HTTP_ACCEPT', ''), 'application/ld+json');
  50         }
  51
  52         /**
  53          * Checks incoming message from the inbox
  54          *
  55          * @param $body
  56          * @param $header
  57          * @param integer $uid User ID
  58          */
  59         public static function processInbox($body, $header, $uid)
  60         {
  61                 $http_signer = HTTPSignature::getSigner($body, $header);
  62                 if (empty($http_signer)) {
  63                         Logger::log('Invalid HTTP signature, message will be discarded.', Logger::DEBUG);
  64                         return;
  65                 } else {
  66                         Logger::log('HTTP signature is signed by ' . $http_signer, Logger::DEBUG);
  67                 }
  68
  69                 $activity = json_decode($body, true);
  70
  71                 if (empty($activity)) {
  72                         Logger::log('Invalid body.', Logger::DEBUG);
  73                         return;
  74                 }
  75
  76                 $ldactivity = JsonLD::compact($activity);
  77
  78                 $actor = JsonLD::fetchElement($ldactivity, 'as:actor');
  79
  80                 Logger::log('Message for user ' . $uid . ' is from actor ' . $actor, Logger::DEBUG);
  81
  82                 if (LDSignature::isSigned($activity)) {
  83                         $ld_signer = LDSignature::getSigner($activity);
  84                         if (empty($ld_signer)) {
  85                                 Logger::log('Invalid JSON-LD signature from ' . $actor, Logger::DEBUG);
  86                         }
  87                         if (!empty($ld_signer && ($actor == $http_signer))) {
  88                                 Logger::log('The HTTP and the JSON-LD signature belong to ' . $ld_signer, Logger::DEBUG);
  89                                 $trust_source = true;
  90                         } elseif (!empty($ld_signer)) {
  91                                 Logger::log('JSON-LD signature is signed by ' . $ld_signer, Logger::DEBUG);
  92                                 $trust_source = true;
  93                         } elseif ($actor == $http_signer) {
  94                                 Logger::log('Bad JSON-LD signature, but HTTP signer fits the actor.', Logger::DEBUG);
  95                                 $trust_source = true;
  96                         } else {
  97                                 Logger::log('Invalid JSON-LD signature and the HTTP signer is different.', Logger::DEBUG);
  98                                 $trust_source = false;
  99                         }
 100                 } elseif ($actor == $http_signer) {
 101                         Logger::log('Trusting post without JSON-LD signature, The actor fits the HTTP signer.', Logger::DEBUG);
 102                         $trust_source = true;
 103                 } else {
 104                         Logger::log('No JSON-LD signature, different actor.', Logger::DEBUG);
 105                         $trust_source = false;
 106                 }
 107
 108                 self::processActivity($ldactivity, $body, $uid, $trust_source);
 109         }
 110
 111         /**
 112          * Fetches the object type for a given object id
 113          *
 114          * @param array  $activity
 115          * @param string $object_id Object ID of the the provided object
 116          *
 117          * @return string with object type
 118          */
 119         private static function fetchObjectType($activity, $object_id)
 120         {
 121                 if (!empty($activity['as:object'])) {
 122                         $object_type = JsonLD::fetchElement($activity['as:object'], '@type');
 123                         if (!empty($object_type)) {
 124                                 return $object_type;
 125                         }
 126                 }
 127
 128                 if (Item::exists(['uri' => $object_id, 'gravity' => [GRAVITY_PARENT, GRAVITY_COMMENT]])) {
 129                         // We just assume "note" since it doesn't make a difference for the further processing
 130                         return 'as:Note';
 131                 }
 132
 133                 $profile = APContact::getByURL($object_id);
 134                 if (!empty($profile['type'])) {
 135                         return 'as:' . $profile['type'];
 136                 }
 137
 138                 $data = ActivityPub::fetchContent($object_id);
 139                 if (!empty($data)) {
 140                         $object = JsonLD::compact($data);
 141                         $type = JsonLD::fetchElement($object, '@type');
 142                         if (!empty($type)) {
 143                                 return $type;
 144                         }
 145                 }
 146
 147                 return null;
 148         }
 149
 150         /**
 151          * Prepare the object array
 152          *
 153          * @param array $activity
 154          * @param integer $uid User ID
 155          * @param $trust_source
 156          *
 157          * @return array with object data
 158          */
 159         private static function prepareObjectData($activity, $uid, &$trust_source)
 160         {
 161                 $actor = JsonLD::fetchElement($activity, 'as:actor');
 162                 if (empty($actor)) {
 163                         Logger::log('Empty actor', Logger::DEBUG);
 164                         return [];
 165                 }
 166
 167                 $type = JsonLD::fetchElement($activity, '@type');
 168
 169                 // Fetch all receivers from to, cc, bto and bcc
 170                 $receivers = self::getReceivers($activity, $actor);
 171
 172                 // When it is a delivery to a personal inbox we add that user to the receivers
 173                 if (!empty($uid)) {
 174                         $owner = User::getOwnerDataById($uid);
 175                         $additional = ['uid:' . $uid => $uid];
 176                         $receivers = array_merge($receivers, $additional);
 177                 }
 178
 179                 Logger::log('Receivers: ' . json_encode($receivers), Logger::DEBUG);
 180
 181                 $object_id = JsonLD::fetchElement($activity, 'as:object');
 182                 if (empty($object_id)) {
 183                         Logger::log('No object found', Logger::DEBUG);
 184                         return [];
 185                 }
 186
 187                 $object_type = self::fetchObjectType($activity, $object_id);
 188
 189                 // Fetch the content only on activities where this matters
 190                 if (in_array($type, ['as:Create', 'as:Update', 'as:Announce'])) {
 191                         if ($type == 'as:Announce') {
 192                                 $trust_source = false;
 193                         }
 194                         $object_data = self::fetchObject($object_id, $activity['as:object'], $trust_source);
 195                         if (empty($object_data)) {
 196                                 Logger::log("Object data couldn't be processed", Logger::DEBUG);
 197                                 return [];
 198                         }
 199                         // We had been able to retrieve the object data - so we can trust the source
 200                         $trust_source = true;
 201                 } elseif (in_array($type, ['as:Like', 'as:Dislike'])) {
 202                         // Create a mostly empty array out of the activity data (instead of the object).
 203                         // This way we later don't have to check for the existence of ech individual array element.
 204                         $object_data = self::processObject($activity);
 205                         $object_data['name'] = $type;
 206                         $object_data['author'] = JsonLD::fetchElement($activity, 'as:actor');
 207                         $object_data['object_id'] = $object_id;
 208                         $object_data['object_type'] = ''; // Since we don't fetch the object, we don't know the type
 209                 } else {
 210                         $object_data = [];
 211                         $object_data['id'] = JsonLD::fetchElement($activity, '@id');
 212                         $object_data['object_id'] = JsonLD::fetchElement($activity, 'as:object');
 213                         $object_data['object_actor'] = JsonLD::fetchElement($activity['as:object'], 'as:actor');
 214                         $object_data['object_object'] = JsonLD::fetchElement($activity['as:object'], 'as:object');
 215                         $object_data['object_type'] = JsonLD::fetchElement($activity['as:object'], '@type');
 216
 217                         // An Undo is done on the object of an object, so we need that type as well
 218                         if ($type == 'as:Undo') {
 219                                 $object_data['object_object_type'] = self::fetchObjectType([], $object_data['object_object']);
 220                         }
 221                 }
 222
 223                 $object_data = self::addActivityFields($object_data, $activity);
 224
 225                 if (empty($object_data['object_type'])) {
 226                         $object_data['object_type'] = $object_type;
 227                 }
 228
 229                 $object_data['type'] = $type;
 230                 $object_data['actor'] = $actor;
 231                 $object_data['receiver'] = array_merge(defaults($object_data, 'receiver', []), $receivers);
 232
 233                 Logger::log('Processing ' . $object_data['type'] . ' ' . $object_data['object_type'] . ' ' . $object_data['id'], Logger::DEBUG);
 234
 235                 return $object_data;
 236         }
 237
 238         /**
 239          * Store the unprocessed data into the conversation table
 240          * This has to be done outside the regular function,
 241          * since we store everything - not only item posts.
 242          *
 243          * @param array  $activity Array with activity data
 244          * @param string $body     The raw message
 245          */
 246         private static function storeConversation($activity, $body)
 247         {
 248                 if (empty($body) || empty($activity['id'])) {
 249                         return;
 250                 }
 251
 252                 $conversation = [
 253                         'protocol' => Conversation::PARCEL_ACTIVITYPUB,
 254                         'item-uri' => $activity['id'],
 255                         'reply-to-uri' => defaults($activity, 'reply-to-id', ''),
 256                         'conversation-href' => defaults($activity, 'context', ''),
 257                         'conversation-uri' => defaults($activity, 'conversation', ''),
 258                         'source' => $body,
 259                         'received' => DateTimeFormat::utcNow()];
 260
 261                 DBA::insert('conversation', $conversation, true);
 262         }
 263
 264         /**
 265          * Processes the activity object
 266          *
 267          * @param array   $activity     Array with activity data
 268          * @param string  $body
 269          * @param integer $uid          User ID
 270          * @param boolean $trust_source Do we trust the source?
 271          */
 272         public static function processActivity($activity, $body = '', $uid = null, $trust_source = false)
 273         {
 274                 $type = JsonLD::fetchElement($activity, '@type');
 275                 if (!$type) {
 276                         Logger::log('Empty type', Logger::DEBUG);
 277                         return;
 278                 }
 279
 280                 if (!JsonLD::fetchElement($activity, 'as:object')) {
 281                         Logger::log('Empty object', Logger::DEBUG);
 282                         return;
 283                 }
 284
 285                 if (!JsonLD::fetchElement($activity, 'as:actor')) {
 286                         Logger::log('Empty actor', Logger::DEBUG);
 287                         return;
 288
 289                 }
 290
 291                 // $trust_source is called by reference and is set to true if the content was retrieved successfully
 292                 $object_data = self::prepareObjectData($activity, $uid, $trust_source);
 293                 if (empty($object_data)) {
 294                         Logger::log('No object data found', Logger::DEBUG);
 295                         return;
 296                 }
 297
 298                 if (!$trust_source) {
 299                         Logger::log('No trust for activity type "' . $type . '", so we quit now.', Logger::DEBUG);
 300                         return;
 301                 }
 302
 303                 self::storeConversation($object_data, $body);
 304
 305                 // Internal flag for thread completion. See Processor.php
 306                 if (!empty($activity['thread-completion'])) {
 307                         $object_data['thread-completion'] = $activity['thread-completion'];
 308                 }
 309
 310                 switch ($type) {
 311                         case 'as:Create':
 312                         case 'as:Announce':
 313                                 if (in_array($object_data['object_type'], self::CONTENT_TYPES)) {
 314                                         ActivityPub\Processor::createItem($object_data);
 315                                 }
 316                                 break;
 317
 318                         case 'as:Like':
 319                                 if (in_array($object_data['object_type'], self::CONTENT_TYPES)) {
 320                                         ActivityPub\Processor::createActivity($object_data, ACTIVITY_LIKE);
 321                                 }
 322                                 break;
 323
 324                         case 'as:Dislike':
 325                                 if (in_array($object_data['object_type'], self::CONTENT_TYPES)) {
 326                                         ActivityPub\Processor::createActivity($object_data, ACTIVITY_DISLIKE);
 327                                 }
 328                                 break;
 329
 330                         case 'as:TentativeAccept':
 331                                 if (in_array($object_data['object_type'], self::CONTENT_TYPES)) {
 332                                         ActivityPub\Processor::createActivity($object_data, ACTIVITY_ATTENDMAYBE);
 333                                 }
 334                                 break;
 335
 336                         case 'as:Update':
 337                                 if (in_array($object_data['object_type'], self::CONTENT_TYPES)) {
 338                                         ActivityPub\Processor::updateItem($object_data);
 339                                 } elseif (in_array($object_data['object_type'], self::ACCOUNT_TYPES)) {
 340                                         ActivityPub\Processor::updatePerson($object_data, $body);
 341                                 }
 342                                 break;
 343
 344                         case 'as:Delete':
 345                                 if ($object_data['object_type'] == 'as:Tombstone') {
 346                                         ActivityPub\Processor::deleteItem($object_data, $body);
 347                                 } elseif (in_array($object_data['object_type'], self::ACCOUNT_TYPES)) {
 348                                         ActivityPub\Processor::deletePerson($object_data, $body);
 349                                 }
 350                                 break;
 351
 352                         case 'as:Follow':
 353                                 if (in_array($object_data['object_type'], self::ACCOUNT_TYPES)) {
 354                                         ActivityPub\Processor::followUser($object_data);
 355                                 }
 356                                 break;
 357
 358                         case 'as:Accept':
 359                                 if ($object_data['object_type'] == 'as:Follow') {
 360                                         ActivityPub\Processor::acceptFollowUser($object_data);
 361                                 } elseif (in_array($object_data['object_type'], self::CONTENT_TYPES)) {
 362                                         ActivityPub\Processor::createActivity($object_data, ACTIVITY_ATTEND);
 363                                 }
 364                                 break;
 365
 366                         case 'as:Reject':
 367                                 if ($object_data['object_type'] == 'as:Follow') {
 368                                         ActivityPub\Processor::rejectFollowUser($object_data);
 369                                 } elseif (in_array($object_data['object_type'], self::CONTENT_TYPES)) {
 370                                         ActivityPub\Processor::createActivity($object_data, ACTIVITY_ATTENDNO);
 371                                 }
 372                                 break;
 373
 374                         case 'as:Undo':
 375                                 if (($object_data['object_type'] == 'as:Follow') &&
 376                                         in_array($object_data['object_object_type'], self::ACCOUNT_TYPES)) {
 377                                         ActivityPub\Processor::undoFollowUser($object_data);
 378                                 } elseif (($object_data['object_type'] == 'as:Accept') &&
 379                                         in_array($object_data['object_object_type'], self::ACCOUNT_TYPES)) {
 380                                         ActivityPub\Processor::rejectFollowUser($object_data);
 381                                 } elseif (in_array($object_data['object_type'], self::ACTIVITY_TYPES) &&
 382                                         in_array($object_data['object_object_type'], self::CONTENT_TYPES)) {
 383                                         ActivityPub\Processor::undoActivity($object_data);
 384                                 }
 385                                 break;
 386
 387                         default:
 388                                 Logger::log('Unknown activity: ' . $type . ' ' . $object_data['object_type'], Logger::DEBUG);
 389                                 break;
 390                 }
 391         }
 392
 393         /**
 394          * Fetch the receiver list from an activity array
 395          *
 396          * @param array $activity
 397          * @param string $actor
 398          *
 399          * @return array with receivers (user id)
 400          */
 401         private static function getReceivers($activity, $actor)
 402         {
 403                 $receivers = [];
 404
 405                 // When it is an answer, we inherite the receivers from the parent
 406                 $replyto = JsonLD::fetchElement($activity, 'as:inReplyTo');
 407                 if (!empty($replyto)) {
 408                         $parents = Item::select(['uid'], ['uri' => $replyto]);
 409                         while ($parent = Item::fetch($parents)) {
 410                                 $receivers['uid:' . $parent['uid']] = $parent['uid'];
 411                         }
 412                 }
 413
 414                 if (!empty($actor)) {
 415                         $profile = APContact::getByURL($actor);
 416                         $followers = defaults($profile, 'followers', '');
 417
 418                         Logger::log('Actor: ' . $actor . ' - Followers: ' . $followers, Logger::DEBUG);
 419                 } else {
 420                         Logger::log('Empty actor', Logger::DEBUG);
 421                         $followers = '';
 422                 }
 423
 424                 foreach (['as:to', 'as:cc', 'as:bto', 'as:bcc'] as $element) {
 425                         $receiver_list = JsonLD::fetchElementArray($activity, $element);
 426                         if (empty($receiver_list)) {
 427                                 continue;
 428                         }
 429
 430                         foreach ($receiver_list as $receiver) {
 431                                 if ($receiver == self::PUBLIC_COLLECTION) {
 432                                         $receivers['uid:0'] = 0;
 433                                 }
 434
 435                                 if (($receiver == self::PUBLIC_COLLECTION) && !empty($actor)) {
 436                                         // This will most likely catch all OStatus connections to Mastodon
 437                                         $condition = ['alias' => [$actor, normalise_link($actor)], 'rel' => [Contact::SHARING, Contact::FRIEND]
 438                                                 , 'archive' => false, 'pending' => false];
 439                                         $contacts = DBA::select('contact', ['uid'], $condition);
 440                                         while ($contact = DBA::fetch($contacts)) {
 441                                                 if ($contact['uid'] != 0) {
 442                                                         $receivers['uid:' . $contact['uid']] = $contact['uid'];
 443                                                 }
 444                                         }
 445                                         DBA::close($contacts);
 446                                 }
 447
 448                                 if (in_array($receiver, [$followers, self::PUBLIC_COLLECTION]) && !empty($actor)) {
 449                                         $networks = [Protocol::ACTIVITYPUB, Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS];
 450                                         $condition = ['nurl' => normalise_link($actor), 'rel' => [Contact::SHARING, Contact::FRIEND],
 451                                                 'network' => $networks, 'archive' => false, 'pending' => false];
 452                                         $contacts = DBA::select('contact', ['uid'], $condition);
 453                                         while ($contact = DBA::fetch($contacts)) {
 454                                                 if ($contact['uid'] != 0) {
 455                                                         $receivers['uid:' . $contact['uid']] = $contact['uid'];
 456                                                 }
 457                                         }
 458                                         DBA::close($contacts);
 459                                         continue;
 460                                 }
 461
 462                                 $condition = ['self' => true, 'nurl' => normalise_link($receiver)];
 463                                 $contact = DBA::selectFirst('contact', ['uid'], $condition);
 464                                 if (!DBA::isResult($contact)) {
 465                                         continue;
 466                                 }
 467                                 $receivers['uid:' . $contact['uid']] = $contact['uid'];
 468                         }
 469                 }
 470
 471                 self::switchContacts($receivers, $actor);
 472
 473                 return $receivers;
 474         }
 475
 476         /**
 477          * Switches existing contacts to ActivityPub
 478          *
 479          * @param integer $cid Contact ID
 480          * @param integer $uid User ID
 481          * @param string $url Profile URL
 482          */
 483         public static function switchContact($cid, $uid, $url)
 484         {
 485                 $profile = ActivityPub::probeProfile($url);
 486                 if (empty($profile)) {
 487                         return;
 488                 }
 489
 490                 Logger::log('Switch contact ' . $cid . ' (' . $profile['url'] . ') for user ' . $uid . ' to ActivityPub');
 491
 492                 $photo = defaults($profile, 'photo', null);
 493                 unset($profile['photo']);
 494                 unset($profile['baseurl']);
 495
 496                 $profile['nurl'] = normalise_link($profile['url']);
 497                 DBA::update('contact', $profile, ['id' => $cid]);
 498
 499                 Contact::updateAvatar($photo, $uid, $cid);
 500
 501                 // Send a new follow request to be sure that the connection still exists
 502                 if (($uid != 0) && DBA::exists('contact', ['id' => $cid, 'rel' => [Contact::SHARING, Contact::FRIEND]])) {
 503                         ActivityPub\Transmitter::sendActivity('Follow', $profile['url'], $uid);
 504                         Logger::log('Send a new follow request to ' . $profile['url'] . ' for user ' . $uid, Logger::DEBUG);
 505                 }
 506         }
 507
 508         /**
 509          *
 510          *
 511          * @param $receivers
 512          * @param $actor
 513          */
 514         private static function switchContacts($receivers, $actor)
 515         {
 516                 if (empty($actor)) {
 517                         return;
 518                 }
 519
 520                 foreach ($receivers as $receiver) {
 521                         $contact = DBA::selectFirst('contact', ['id'], ['uid' => $receiver, 'network' => Protocol::OSTATUS, 'nurl' => normalise_link($actor)]);
 522                         if (DBA::isResult($contact)) {
 523                                 self::switchContact($contact['id'], $receiver, $actor);
 524                         }
 525
 526                         $contact = DBA::selectFirst('contact', ['id'], ['uid' => $receiver, 'network' => Protocol::OSTATUS, 'alias' => [normalise_link($actor), $actor]]);
 527                         if (DBA::isResult($contact)) {
 528                                 self::switchContact($contact['id'], $receiver, $actor);
 529                         }
 530                 }
 531         }
 532
 533         /**
 534          *
 535          *
 536          * @param $object_data
 537          * @param array $activity
 538          *
 539          * @return
 540          */
 541         private static function addActivityFields($object_data, $activity)
 542         {
 543                 if (!empty($activity['published']) && empty($object_data['published'])) {
 544                         $object_data['published'] = JsonLD::fetchElement($activity, 'as:published', '@value');
 545                 }
 546
 547                 if (!empty($activity['diaspora:guid']) && empty($object_data['diaspora:guid'])) {
 548                         $object_data['diaspora:guid'] = JsonLD::fetchElement($activity, 'diaspora:guid');
 549                 }
 550
 551                 $object_data['service'] = JsonLD::fetchElement($activity, 'as:instrument', 'as:name', '@type', 'as:Service');
 552
 553                 return $object_data;
 554         }
 555
 556         /**
 557          * Fetches the object data from external ressources if needed
 558          *
 559          * @param string  $object_id    Object ID of the the provided object
 560          * @param array   $object       The provided object array
 561          * @param boolean $trust_source Do we trust the provided object?
 562          *
 563          * @return array with trusted and valid object data
 564          */
 565         private static function fetchObject($object_id, $object = [], $trust_source = false)
 566         {
 567                 // By fetching the type we check if the object is complete.
 568                 $type = JsonLD::fetchElement($object, '@type');
 569
 570                 if (!$trust_source || empty($type)) {
 571                         $data = ActivityPub::fetchContent($object_id);
 572                         if (!empty($data)) {
 573                                 $object = JsonLD::compact($data);
 574                                 Logger::log('Fetched content for ' . $object_id, Logger::DEBUG);
 575                         } else {
 576                                 Logger::log('Empty content for ' . $object_id . ', check if content is available locally.', Logger::DEBUG);
 577
 578                                 $item = Item::selectFirst([], ['uri' => $object_id]);
 579                                 if (!DBA::isResult($item)) {
 580                                         Logger::log('Object with url ' . $object_id . ' was not found locally.', Logger::DEBUG);
 581                                         return false;
 582                                 }
 583                                 Logger::log('Using already stored item for url ' . $object_id, Logger::DEBUG);
 584                                 $data = ActivityPub\Transmitter::createNote($item);
 585                                 $object = JsonLD::compact($data);
 586                         }
 587                 } else {
 588                         Logger::log('Using original object for url ' . $object_id, Logger::DEBUG);
 589                 }
 590
 591                 $type = JsonLD::fetchElement($object, '@type');
 592
 593                 if (empty($type)) {
 594                         Logger::log('Empty type', Logger::DEBUG);
 595                         return false;
 596                 }
 597
 598                 if (in_array($type, self::CONTENT_TYPES)) {
 599                         return self::processObject($object);
 600                 }
 601
 602                 if ($type == 'as:Announce') {
 603                         $object_id = JsonLD::fetchElement($object, 'object');
 604                         if (empty($object_id)) {
 605                                 return false;
 606                         }
 607                         return self::fetchObject($object_id);
 608                 }
 609
 610                 Logger::log('Unhandled object type: ' . $type, Logger::DEBUG);
 611         }
 612
 613         /**
 614          * Convert tags from JSON-LD format into a simplified format
 615          *
 616          * @param array $tags Tags in JSON-LD format
 617          *
 618          * @return array with tags in a simplified format
 619          */
 620         private static function processTags($tags)
 621         {
 622                 $taglist = [];
 623
 624                 if (empty($tags)) {
 625                         return [];
 626                 }
 627
 628                 foreach ($tags as $tag) {
 629                         if (empty($tag)) {
 630                                 continue;
 631                         }
 632
 633                         $taglist[] = ['type' => str_replace('as:', '', JsonLD::fetchElement($tag, '@type')),
 634                                 'href' => JsonLD::fetchElement($tag, 'as:href'),
 635                                 'name' => JsonLD::fetchElement($tag, 'as:name')];
 636                 }
 637                 return $taglist;
 638         }
 639
 640         /**
 641          * Convert attachments from JSON-LD format into a simplified format
 642          *
 643          * @param array $attachments Attachments in JSON-LD format
 644          *
 645          * @return array with attachmants in a simplified format
 646          */
 647         private static function processAttachments($attachments)
 648         {
 649                 $attachlist = [];
 650
 651                 if (empty($attachments)) {
 652                         return [];
 653                 }
 654
 655                 foreach ($attachments as $attachment) {
 656                         if (empty($attachment)) {
 657                                 continue;
 658                         }
 659
 660                         $attachlist[] = ['type' => str_replace('as:', '', JsonLD::fetchElement($attachment, '@type')),
 661                                 'mediaType' => JsonLD::fetchElement($attachment, 'as:mediaType'),
 662                                 'name' => JsonLD::fetchElement($attachment, 'as:name'),
 663                                 'url' => JsonLD::fetchElement($attachment, 'as:url')];
 664                 }
 665                 return $attachlist;
 666         }
 667
 668         /**
 669          * Fetches data from the object part of an activity
 670          *
 671          * @param array $object
 672          *
 673          * @return array
 674          */
 675         private static function processObject($object)
 676         {
 677                 if (!JsonLD::fetchElement($object, '@id')) {
 678                         return false;
 679                 }
 680
 681                 $object_data = [];
 682                 $object_data['object_type'] = JsonLD::fetchElement($object, '@type');
 683                 $object_data['id'] = JsonLD::fetchElement($object, '@id');
 684
 685                 $object_data['reply-to-id'] = JsonLD::fetchElement($object, 'as:inReplyTo');
 686
 687                 if (empty($object_data['reply-to-id'])) {
 688                         $object_data['reply-to-id'] = $object_data['id'];
 689                 }
 690
 691                 $object_data['published'] = JsonLD::fetchElement($object, 'as:published', '@value');
 692                 $object_data['updated'] = JsonLD::fetchElement($object, 'as:updated', '@value');
 693
 694                 if (empty($object_data['updated'])) {
 695                         $object_data['updated'] = $object_data['published'];
 696                 }
 697
 698                 if (empty($object_data['published']) && !empty($object_data['updated'])) {
 699                         $object_data['published'] = $object_data['updated'];
 700                 }
 701
 702                 $actor = JsonLD::fetchElement($object, 'as:attributedTo');
 703                 if (empty($actor)) {
 704                         $actor = JsonLD::fetchElement($object, 'as:actor');
 705                 }
 706
 707                 $object_data['diaspora:guid'] = JsonLD::fetchElement($object, 'diaspora:guid');
 708                 $object_data['diaspora:comment'] = JsonLD::fetchElement($object, 'diaspora:comment');
 709                 $object_data['diaspora:like'] = JsonLD::fetchElement($object, 'diaspora:like');
 710                 $object_data['actor'] = $object_data['author'] = $actor;
 711                 $object_data['context'] = JsonLD::fetchElement($object, 'as:context');
 712                 $object_data['conversation'] = JsonLD::fetchElement($object, 'ostatus:conversation');
 713                 $object_data['sensitive'] = JsonLD::fetchElement($object, 'as:sensitive');
 714                 $object_data['name'] = JsonLD::fetchElement($object, 'as:name');
 715                 $object_data['summary'] = JsonLD::fetchElement($object, 'as:summary');
 716                 $object_data['content'] = JsonLD::fetchElement($object, 'as:content');
 717                 $object_data['source'] = JsonLD::fetchElement($object, 'as:source', 'as:content', 'as:mediaType', 'text/bbcode');
 718                 $object_data['start-time'] = JsonLD::fetchElement($object, 'as:startTime', '@value');
 719                 $object_data['end-time'] = JsonLD::fetchElement($object, 'as:endTime', '@value');
 720                 $object_data['location'] = JsonLD::fetchElement($object, 'as:location', 'as:name', '@type', 'as:Place');
 721                 $object_data['latitude'] = JsonLD::fetchElement($object, 'as:location', 'as:latitude', '@type', 'as:Place');
 722                 $object_data['latitude'] = JsonLD::fetchElement($object_data, 'latitude', '@value');
 723                 $object_data['longitude'] = JsonLD::fetchElement($object, 'as:location', 'as:longitude', '@type', 'as:Place');
 724                 $object_data['longitude'] = JsonLD::fetchElement($object_data, 'longitude', '@value');
 725                 $object_data['attachments'] = self::processAttachments(JsonLD::fetchElementArray($object, 'as:attachment'));
 726                 $object_data['tags'] = self::processTags(JsonLD::fetchElementArray($object, 'as:tag'));
 727                 $object_data['generator'] = JsonLD::fetchElement($object, 'as:generator', 'as:name', '@type', 'as:Application');
 728                 $object_data['alternate-url'] = JsonLD::fetchElement($object, 'as:url');
 729
 730                 // Special treatment for Hubzilla links
 731                 if (is_array($object_data['alternate-url'])) {
 732                         $object_data['alternate-url'] = JsonLD::fetchElement($object_data['alternate-url'], 'as:href');
 733
 734                         if (!is_string($object_data['alternate-url'])) {
 735                                 $object_data['alternate-url'] = JsonLD::fetchElement($object['as:url'], 'as:href');
 736                         }
 737                 }
 738
 739                 $object_data['receiver'] = self::getReceivers($object, $object_data['actor']);
 740
 741                 // Common object data:
 742
 743                 // Unhandled
 744                 // @context, type, actor, signature, mediaType, duration, replies, icon
 745
 746                 // Also missing: (Defined in the standard, but currently unused)
 747                 // audience, preview, endTime, startTime, image
 748
 749                 // Data in Notes:
 750
 751                 // Unhandled
 752                 // contentMap, announcement_count, announcements, context_id, likes, like_count
 753                 // inReplyToStatusId, shares, quoteUrl, statusnetConversationId
 754
 755                 // Data in video:
 756
 757                 // To-Do?
 758                 // category, licence, language, commentsEnabled
 759
 760                 // Unhandled
 761                 // views, waitTranscoding, state, support, subtitleLanguage
 762                 // likes, dislikes, shares, comments
 763
 764                 return $object_data;
 765         }
 766 }