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\Core\Logger;
   9 use Friendica\Core\Protocol;
  10 use Friendica\Model\Contact;
  11 use Friendica\Model\APContact;
  12 use Friendica\Model\Conversation;
  13 use Friendica\Model\Item;
  14 use Friendica\Model\User;
  15 use Friendica\Protocol\ActivityPub;
  16 use Friendica\Util\DateTimeFormat;
  17 use Friendica\Util\HTTPSignature;
  18 use Friendica\Util\JsonLD;
  19 use Friendica\Util\LDSignature;
  20 use Friendica\Util\Strings;
  21
  22 /**
  23  * @brief ActivityPub Receiver Protocol class
  24  *
  25  * To-Do:
  26  * - Undo Announce
  27  *
  28  * Check what this is meant to do:
  29  * - Add
  30  * - Block
  31  * - Flag
  32  * - Remove
  33  * - Undo Block
  34  */
  35 class Receiver
  36 {
  37         const PUBLIC_COLLECTION = 'as:Public';
  38         const ACCOUNT_TYPES = ['as:Person', 'as:Organization', 'as:Service', 'as:Group', 'as:Application'];
  39         const CONTENT_TYPES = ['as:Note', 'as:Article', 'as:Video', 'as:Image', 'as:Event'];
  40         const ACTIVITY_TYPES = ['as:Like', 'as:Dislike', 'as:Accept', 'as:Reject', 'as:TentativeAccept'];
  41
  42         /**
  43          * Checks if the web request is done for the AP protocol
  44          *
  45          * @return bool is it AP?
  46          */
  47         public static function isRequest()
  48         {
  49                 return stristr(defaults($_SERVER, 'HTTP_ACCEPT', ''), 'application/activity+json') ||
  50                         stristr(defaults($_SERVER, 'HTTP_ACCEPT', ''), 'application/ld+json');
  51         }
  52
  53         /**
  54          * Checks incoming message from the inbox
  55          *
  56          * @param         $body
  57          * @param         $header
  58          * @param integer $uid User ID
  59          * @throws \Exception
  60          */
  61         public static function processInbox($body, $header, $uid)
  62         {
  63                 $http_signer = HTTPSignature::getSigner($body, $header);
  64                 if (empty($http_signer)) {
  65                         Logger::log('Invalid HTTP signature, message will be discarded.', Logger::DEBUG);
  66                         return;
  67                 } else {
  68                         Logger::log('HTTP signature is signed by ' . $http_signer, Logger::DEBUG);
  69                 }
  70
  71                 $activity = json_decode($body, true);
  72
  73                 if (empty($activity)) {
  74                         Logger::log('Invalid body.', Logger::DEBUG);
  75                         return;
  76                 }
  77
  78                 $ldactivity = JsonLD::compact($activity);
  79
  80                 $actor = JsonLD::fetchElement($ldactivity, 'as:actor');
  81
  82                 Logger::log('Message for user ' . $uid . ' is from actor ' . $actor, Logger::DEBUG);
  83
  84                 if (LDSignature::isSigned($activity)) {
  85                         $ld_signer = LDSignature::getSigner($activity);
  86                         if (empty($ld_signer)) {
  87                                 Logger::log('Invalid JSON-LD signature from ' . $actor, Logger::DEBUG);
  88                         }
  89                         if (!empty($ld_signer && ($actor == $http_signer))) {
  90                                 Logger::log('The HTTP and the JSON-LD signature belong to ' . $ld_signer, Logger::DEBUG);
  91                                 $trust_source = true;
  92                         } elseif (!empty($ld_signer)) {
  93                                 Logger::log('JSON-LD signature is signed by ' . $ld_signer, Logger::DEBUG);
  94                                 $trust_source = true;
  95                         } elseif ($actor == $http_signer) {
  96                                 Logger::log('Bad JSON-LD signature, but HTTP signer fits the actor.', Logger::DEBUG);
  97                                 $trust_source = true;
  98                         } else {
  99                                 Logger::log('Invalid JSON-LD signature and the HTTP signer is different.', Logger::DEBUG);
 100                                 $trust_source = false;
 101                         }
 102                 } elseif ($actor == $http_signer) {
 103                         Logger::log('Trusting post without JSON-LD signature, The actor fits the HTTP signer.', Logger::DEBUG);
 104                         $trust_source = true;
 105                 } else {
 106                         Logger::log('No JSON-LD signature, different actor.', Logger::DEBUG);
 107                         $trust_source = false;
 108                 }
 109
 110                 self::processActivity($ldactivity, $body, $uid, $trust_source);
 111         }
 112
 113         /**
 114          * Fetches the object type for a given object id
 115          *
 116          * @param array   $activity
 117          * @param string  $object_id Object ID of the the provided object
 118          * @param integer $uid       User ID
 119          *
 120          * @return string with object type
 121          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 122          * @throws \ImagickException
 123          */
 124         private static function fetchObjectType($activity, $object_id, $uid = 0)
 125         {
 126                 if (!empty($activity['as:object'])) {
 127                         $object_type = JsonLD::fetchElement($activity['as:object'], '@type');
 128                         if (!empty($object_type)) {
 129                                 return $object_type;
 130                         }
 131                 }
 132
 133                 if (Item::exists(['uri' => $object_id, 'gravity' => [GRAVITY_PARENT, GRAVITY_COMMENT]])) {
 134                         // We just assume "note" since it doesn't make a difference for the further processing
 135                         return 'as:Note';
 136                 }
 137
 138                 $profile = APContact::getByURL($object_id);
 139                 if (!empty($profile['type'])) {
 140                         return 'as:' . $profile['type'];
 141                 }
 142
 143                 $data = ActivityPub::fetchContent($object_id, $uid);
 144                 if (!empty($data)) {
 145                         $object = JsonLD::compact($data);
 146                         $type = JsonLD::fetchElement($object, '@type');
 147                         if (!empty($type)) {
 148                                 return $type;
 149                         }
 150                 }
 151
 152                 return null;
 153         }
 154
 155         /**
 156          * Prepare the object array
 157          *
 158          * @param array   $activity
 159          * @param integer $uid User ID
 160          * @param         $trust_source
 161          *
 162          * @return array with object data
 163          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 164          * @throws \ImagickException
 165          */
 166         private static function prepareObjectData($activity, $uid, &$trust_source)
 167         {
 168                 $actor = JsonLD::fetchElement($activity, 'as:actor');
 169                 if (empty($actor)) {
 170                         Logger::log('Empty actor', Logger::DEBUG);
 171                         return [];
 172                 }
 173
 174                 $type = JsonLD::fetchElement($activity, '@type');
 175
 176                 // Fetch all receivers from to, cc, bto and bcc
 177                 $receivers = self::getReceivers($activity, $actor);
 178
 179                 // When it is a delivery to a personal inbox we add that user to the receivers
 180                 if (!empty($uid)) {
 181                         $additional = ['uid:' . $uid => $uid];
 182                         $receivers = array_merge($receivers, $additional);
 183                 } else {
 184                         // We possibly need some user to fetch private content,
 185                         // so we fetch the first out ot the list.
 186                         $uid = self::getFirstUserFromReceivers($receivers);
 187                 }
 188
 189                 Logger::log('Receivers: ' . $uid . ' - ' . json_encode($receivers), Logger::DEBUG);
 190
 191                 $object_id = JsonLD::fetchElement($activity, 'as:object');
 192                 if (empty($object_id)) {
 193                         Logger::log('No object found', Logger::DEBUG);
 194                         return [];
 195                 }
 196
 197                 $object_type = self::fetchObjectType($activity, $object_id, $uid);
 198
 199                 // Fetch the content only on activities where this matters
 200                 if (in_array($type, ['as:Create', 'as:Update', 'as:Announce'])) {
 201                         if ($type == 'as:Announce') {
 202                                 $trust_source = false;
 203                         }
 204                         $object_data = self::fetchObject($object_id, $activity['as:object'], $trust_source, $uid);
 205                         if (empty($object_data)) {
 206                                 Logger::log("Object data couldn't be processed", Logger::DEBUG);
 207                                 return [];
 208                         }
 209                         // We had been able to retrieve the object data - so we can trust the source
 210                         $trust_source = true;
 211                 } elseif (in_array($type, ['as:Like', 'as:Dislike'])) {
 212                         // Create a mostly empty array out of the activity data (instead of the object).
 213                         // This way we later don't have to check for the existence of ech individual array element.
 214                         $object_data = self::processObject($activity);
 215                         $object_data['name'] = $type;
 216                         $object_data['author'] = JsonLD::fetchElement($activity, 'as:actor');
 217                         $object_data['object_id'] = $object_id;
 218                         $object_data['object_type'] = ''; // Since we don't fetch the object, we don't know the type
 219                 } else {
 220                         $object_data = [];
 221                         $object_data['id'] = JsonLD::fetchElement($activity, '@id');
 222                         $object_data['object_id'] = JsonLD::fetchElement($activity, 'as:object');
 223                         $object_data['object_actor'] = JsonLD::fetchElement($activity['as:object'], 'as:actor');
 224                         $object_data['object_object'] = JsonLD::fetchElement($activity['as:object'], 'as:object');
 225                         $object_data['object_type'] = JsonLD::fetchElement($activity['as:object'], '@type');
 226
 227                         // An Undo is done on the object of an object, so we need that type as well
 228                         if ($type == 'as:Undo') {
 229                                 $object_data['object_object_type'] = self::fetchObjectType([], $object_data['object_object'], $uid);
 230                         }
 231                 }
 232
 233                 $object_data = self::addActivityFields($object_data, $activity);
 234
 235                 if (empty($object_data['object_type'])) {
 236                         $object_data['object_type'] = $object_type;
 237                 }
 238
 239                 $object_data['type'] = $type;
 240                 $object_data['actor'] = $actor;
 241                 $object_data['item_receiver'] = $receivers;
 242                 $object_data['receiver'] = array_merge(defaults($object_data, 'receiver', []), $receivers);
 243
 244                 Logger::log('Processing ' . $object_data['type'] . ' ' . $object_data['object_type'] . ' ' . $object_data['id'], Logger::DEBUG);
 245
 246                 return $object_data;
 247         }
 248
 249         /**
 250          * Fetches the first user id from the receiver array
 251          *
 252          * @param array $receivers Array with receivers
 253          * @return integer user id;
 254          */
 255         public static function getFirstUserFromReceivers($receivers)
 256         {
 257                 foreach ($receivers as $receiver) {
 258                         if (!empty($receiver)) {
 259                                 return $receiver;
 260                         }
 261                 }
 262                 return 0;
 263         }
 264
 265         /**
 266          * Store the unprocessed data into the conversation table
 267          * This has to be done outside the regular function,
 268          * since we store everything - not only item posts.
 269          *
 270          * @param array  $activity Array with activity data
 271          * @param string $body     The raw message
 272          * @throws \Exception
 273          */
 274         private static function storeConversation($activity, $body)
 275         {
 276                 if (empty($body) || empty($activity['id'])) {
 277                         return;
 278                 }
 279
 280                 $conversation = [
 281                         'protocol' => Conversation::PARCEL_ACTIVITYPUB,
 282                         'item-uri' => $activity['id'],
 283                         'reply-to-uri' => defaults($activity, 'reply-to-id', ''),
 284                         'conversation-href' => defaults($activity, 'context', ''),
 285                         'conversation-uri' => defaults($activity, 'conversation', ''),
 286                         'source' => $body,
 287                         'received' => DateTimeFormat::utcNow()];
 288
 289                 DBA::insert('conversation', $conversation, true);
 290         }
 291
 292         /**
 293          * Processes the activity object
 294          *
 295          * @param array   $activity     Array with activity data
 296          * @param string  $body
 297          * @param integer $uid          User ID
 298          * @param boolean $trust_source Do we trust the source?
 299          * @throws \Exception
 300          */
 301         public static function processActivity($activity, $body = '', $uid = null, $trust_source = false)
 302         {
 303                 $type = JsonLD::fetchElement($activity, '@type');
 304                 if (!$type) {
 305                         Logger::log('Empty type', Logger::DEBUG);
 306                         return;
 307                 }
 308
 309                 if (!JsonLD::fetchElement($activity, 'as:object')) {
 310                         Logger::log('Empty object', Logger::DEBUG);
 311                         return;
 312                 }
 313
 314                 if (!JsonLD::fetchElement($activity, 'as:actor')) {
 315                         Logger::log('Empty actor', Logger::DEBUG);
 316                         return;
 317
 318                 }
 319
 320                 // Don't trust the source if "actor" differs from "attributedTo". The content could be forged.
 321                 if ($trust_source && ($type == 'as:Create') && is_array($activity['as:object'])) {
 322                         $actor = JsonLD::fetchElement($activity, 'as:actor');
 323                         $attributed_to = JsonLD::fetchElement($activity['as:object'], 'as:attributedTo');
 324                         $trust_source = ($actor == $attributed_to);
 325                         if (!$trust_source) {
 326                                 Logger::log('Not trusting actor: ' . $actor . '. It differs from attributedTo: ' . $attributed_to, Logger::DEBUG);
 327                         }
 328                 }
 329
 330                 // $trust_source is called by reference and is set to true if the content was retrieved successfully
 331                 $object_data = self::prepareObjectData($activity, $uid, $trust_source);
 332                 if (empty($object_data)) {
 333                         Logger::log('No object data found', Logger::DEBUG);
 334                         return;
 335                 }
 336
 337                 if (!$trust_source) {
 338                         Logger::log('No trust for activity type "' . $type . '", so we quit now.', Logger::DEBUG);
 339                         return;
 340                 }
 341
 342                 // Only store content related stuff - and no announces, since they possibly overwrite the original content
 343                 if (in_array($object_data['object_type'], self::CONTENT_TYPES) && ($type != 'as:Announce')) {
 344                         self::storeConversation($object_data, $body);
 345                 }
 346
 347                 // Internal flag for thread completion. See Processor.php
 348                 if (!empty($activity['thread-completion'])) {
 349                         $object_data['thread-completion'] = $activity['thread-completion'];
 350                 }
 351
 352                 switch ($type) {
 353                         case 'as:Create':
 354                         case 'as:Announce':
 355                                 if (in_array($object_data['object_type'], self::CONTENT_TYPES)) {
 356                                         ActivityPub\Processor::createItem($object_data);
 357                                 }
 358                                 break;
 359
 360                         case 'as:Like':
 361                                 if (in_array($object_data['object_type'], self::CONTENT_TYPES)) {
 362                                         ActivityPub\Processor::createActivity($object_data, ACTIVITY_LIKE);
 363                                 }
 364                                 break;
 365
 366                         case 'as:Dislike':
 367                                 if (in_array($object_data['object_type'], self::CONTENT_TYPES)) {
 368                                         ActivityPub\Processor::createActivity($object_data, ACTIVITY_DISLIKE);
 369                                 }
 370                                 break;
 371
 372                         case 'as:TentativeAccept':
 373                                 if (in_array($object_data['object_type'], self::CONTENT_TYPES)) {
 374                                         ActivityPub\Processor::createActivity($object_data, ACTIVITY_ATTENDMAYBE);
 375                                 }
 376                                 break;
 377
 378                         case 'as:Update':
 379                                 if (in_array($object_data['object_type'], self::CONTENT_TYPES)) {
 380                                         ActivityPub\Processor::updateItem($object_data);
 381                                 } elseif (in_array($object_data['object_type'], self::ACCOUNT_TYPES)) {
 382                                         ActivityPub\Processor::updatePerson($object_data, $body);
 383                                 }
 384                                 break;
 385
 386                         case 'as:Delete':
 387                                 if ($object_data['object_type'] == 'as:Tombstone') {
 388                                         ActivityPub\Processor::deleteItem($object_data, $body);
 389                                 } elseif (in_array($object_data['object_type'], self::ACCOUNT_TYPES)) {
 390                                         ActivityPub\Processor::deletePerson($object_data, $body);
 391                                 }
 392                                 break;
 393
 394                         case 'as:Follow':
 395                                 if (in_array($object_data['object_type'], self::ACCOUNT_TYPES)) {
 396                                         ActivityPub\Processor::followUser($object_data);
 397                                 }
 398                                 break;
 399
 400                         case 'as:Accept':
 401                                 if ($object_data['object_type'] == 'as:Follow') {
 402                                         ActivityPub\Processor::acceptFollowUser($object_data);
 403                                 } elseif (in_array($object_data['object_type'], self::CONTENT_TYPES)) {
 404                                         ActivityPub\Processor::createActivity($object_data, ACTIVITY_ATTEND);
 405                                 }
 406                                 break;
 407
 408                         case 'as:Reject':
 409                                 if ($object_data['object_type'] == 'as:Follow') {
 410                                         ActivityPub\Processor::rejectFollowUser($object_data);
 411                                 } elseif (in_array($object_data['object_type'], self::CONTENT_TYPES)) {
 412                                         ActivityPub\Processor::createActivity($object_data, ACTIVITY_ATTENDNO);
 413                                 }
 414                                 break;
 415
 416                         case 'as:Undo':
 417                                 if (($object_data['object_type'] == 'as:Follow') &&
 418                                         in_array($object_data['object_object_type'], self::ACCOUNT_TYPES)) {
 419                                         ActivityPub\Processor::undoFollowUser($object_data);
 420                                 } elseif (($object_data['object_type'] == 'as:Accept') &&
 421                                         in_array($object_data['object_object_type'], self::ACCOUNT_TYPES)) {
 422                                         ActivityPub\Processor::rejectFollowUser($object_data);
 423                                 } elseif (in_array($object_data['object_type'], self::ACTIVITY_TYPES) &&
 424                                         in_array($object_data['object_object_type'], self::CONTENT_TYPES)) {
 425                                         ActivityPub\Processor::undoActivity($object_data);
 426                                 }
 427                                 break;
 428
 429                         default:
 430                                 Logger::log('Unknown activity: ' . $type . ' ' . $object_data['object_type'], Logger::DEBUG);
 431                                 break;
 432                 }
 433         }
 434
 435         /**
 436          * Fetch the receiver list from an activity array
 437          *
 438          * @param array  $activity
 439          * @param string $actor
 440          * @param array  $tags
 441          *
 442          * @return array with receivers (user id)
 443          * @throws \Exception
 444          */
 445         private static function getReceivers($activity, $actor, $tags = [])
 446         {
 447                 $receivers = [];
 448
 449                 // When it is an answer, we inherite the receivers from the parent
 450                 $replyto = JsonLD::fetchElement($activity, 'as:inReplyTo');
 451                 if (!empty($replyto)) {
 452                         $parents = Item::select(['uid'], ['uri' => $replyto]);
 453                         while ($parent = Item::fetch($parents)) {
 454                                 $receivers['uid:' . $parent['uid']] = $parent['uid'];
 455                         }
 456                 }
 457
 458                 if (!empty($actor)) {
 459                         $profile = APContact::getByURL($actor);
 460                         $followers = defaults($profile, 'followers', '');
 461
 462                         Logger::log('Actor: ' . $actor . ' - Followers: ' . $followers, Logger::DEBUG);
 463                 } else {
 464                         Logger::log('Empty actor', Logger::DEBUG);
 465                         $followers = '';
 466                 }
 467
 468                 foreach (['as:to', 'as:cc', 'as:bto', 'as:bcc'] as $element) {
 469                         $receiver_list = JsonLD::fetchElementArray($activity, $element);
 470                         if (empty($receiver_list)) {
 471                                 continue;
 472                         }
 473
 474                         foreach ($receiver_list as $receiver) {
 475                                 if ($receiver == self::PUBLIC_COLLECTION) {
 476                                         $receivers['uid:0'] = 0;
 477                                 }
 478
 479                                 if (($receiver == self::PUBLIC_COLLECTION) && !empty($actor)) {
 480                                         // This will most likely catch all OStatus connections to Mastodon
 481                                         $condition = ['alias' => [$actor, Strings::normaliseLink($actor)], 'rel' => [Contact::SHARING, Contact::FRIEND]
 482                                                 , 'archive' => false, 'pending' => false];
 483                                         $contacts = DBA::select('contact', ['uid'], $condition);
 484                                         while ($contact = DBA::fetch($contacts)) {
 485                                                 if ($contact['uid'] != 0) {
 486                                                         $receivers['uid:' . $contact['uid']] = $contact['uid'];
 487                                                 }
 488                                         }
 489                                         DBA::close($contacts);
 490                                 }
 491
 492                                 if (in_array($receiver, [$followers, self::PUBLIC_COLLECTION]) && !empty($actor)) {
 493                                         $receivers = array_merge($receivers, self::getReceiverForActor($actor, $tags));
 494                                         continue;
 495                                 }
 496
 497                                 // Fetching all directly addressed receivers
 498                                 $condition = ['self' => true, 'nurl' => Strings::normaliseLink($receiver)];
 499                                 $contact = DBA::selectFirst('contact', ['uid', 'contact-type'], $condition);
 500                                 if (!DBA::isResult($contact)) {
 501                                         continue;
 502                                 }
 503
 504                                 // Check if the potential receiver is following the actor
 505                                 // Exception: The receiver is targetted via "to" or this is a comment
 506                                 if ((($element != 'as:to') && empty($replyto)) || ($contact['contact-type'] == Contact::ACCOUNT_TYPE_COMMUNITY)) {
 507                                         $networks = [Protocol::ACTIVITYPUB, Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS];
 508                                         $condition = ['nurl' => Strings::normaliseLink($actor), 'rel' => [Contact::SHARING, Contact::FRIEND],
 509                                                 'network' => $networks, 'archive' => false, 'pending' => false, 'uid' => $contact['uid']];
 510
 511                                         // Forum posts are only accepted from forum contacts
 512                                         if ($contact['contact-type'] == Contact::ACCOUNT_TYPE_COMMUNITY) {
 513                                                 $condition['rel'] = [Contact::SHARING, Contact::FRIEND, Contact::FOLLOWER];
 514                                         }
 515
 516                                         if (!DBA::exists('contact', $condition)) {
 517                                                 continue;
 518                                         }
 519                                 }
 520
 521                                 $receivers['uid:' . $contact['uid']] = $contact['uid'];
 522                         }
 523                 }
 524
 525                 self::switchContacts($receivers, $actor);
 526
 527                 return $receivers;
 528         }
 529
 530         /**
 531          * Fetch the receiver list of a given actor
 532          *
 533          * @param string $actor
 534          * @param array  $tags
 535          *
 536          * @return array with receivers (user id)
 537          * @throws \Exception
 538          */
 539         public static function getReceiverForActor($actor, $tags)
 540         {
 541                 $receivers = [];
 542                 $networks = [Protocol::ACTIVITYPUB, Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS];
 543                 $condition = ['nurl' => Strings::normaliseLink($actor), 'rel' => [Contact::SHARING, Contact::FRIEND, Contact::FOLLOWER],
 544                         'network' => $networks, 'archive' => false, 'pending' => false];
 545                 $contacts = DBA::select('contact', ['uid', 'rel'], $condition);
 546                 while ($contact = DBA::fetch($contacts)) {
 547                         if (self::isValidReceiverForActor($contact, $actor, $tags)) {
 548                                 $receivers['uid:' . $contact['uid']] = $contact['uid'];
 549                         }
 550                 }
 551                 DBA::close($contacts);
 552                 return $receivers;
 553         }
 554
 555         /**
 556          * Tests if the contact is a valid receiver for this actor
 557          *
 558          * @param array  $contact
 559          * @param string $actor
 560          * @param array  $tags
 561          *
 562          * @return bool with receivers (user id)
 563          * @throws \Exception
 564          */
 565         private static function isValidReceiverForActor($contact, $actor, $tags)
 566         {
 567                 // Public contacts are no valid receiver
 568                 if ($contact['uid'] == 0) {
 569                         return false;
 570                 }
 571
 572                 // Are we following the contact? Then this is a valid receiver
 573                 if (in_array($contact['rel'], [Contact::SHARING, Contact::FRIEND])) {
 574                         return true;
 575                 }
 576
 577                 // When the possible receiver isn't a community, then it is no valid receiver
 578                 $owner = User::getOwnerDataById($contact['uid']);
 579                 if (empty($owner) || ($owner['contact-type'] != Contact::ACCOUNT_TYPE_COMMUNITY)) {
 580                         return false;
 581                 }
 582
 583                 // Is the community account tagged?
 584                 foreach ($tags as $tag) {
 585                         if ($tag['type'] != 'Mention') {
 586                                 continue;
 587                         }
 588
 589                         if ($tag['href'] == $owner['url']) {
 590                                 return true;
 591                         }
 592                 }
 593
 594                 return false;
 595         }
 596
 597         /**
 598          * Switches existing contacts to ActivityPub
 599          *
 600          * @param integer $cid Contact ID
 601          * @param integer $uid User ID
 602          * @param string  $url Profile URL
 603          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 604          * @throws \ImagickException
 605          */
 606         public static function switchContact($cid, $uid, $url)
 607         {
 608                 $profile = ActivityPub::probeProfile($url);
 609                 if (empty($profile)) {
 610                         return;
 611                 }
 612
 613                 Logger::log('Switch contact ' . $cid . ' (' . $profile['url'] . ') for user ' . $uid . ' to ActivityPub');
 614
 615                 $photo = defaults($profile, 'photo', null);
 616                 unset($profile['photo']);
 617                 unset($profile['baseurl']);
 618                 unset($profile['guid']);
 619
 620                 $profile['nurl'] = Strings::normaliseLink($profile['url']);
 621                 DBA::update('contact', $profile, ['id' => $cid]);
 622
 623                 Contact::updateAvatar($photo, $uid, $cid);
 624
 625                 // Send a new follow request to be sure that the connection still exists
 626                 if (($uid != 0) && DBA::exists('contact', ['id' => $cid, 'rel' => [Contact::SHARING, Contact::FRIEND]])) {
 627                         ActivityPub\Transmitter::sendActivity('Follow', $profile['url'], $uid);
 628                         Logger::log('Send a new follow request to ' . $profile['url'] . ' for user ' . $uid, Logger::DEBUG);
 629                 }
 630         }
 631
 632         /**
 633          *
 634          *
 635          * @param $receivers
 636          * @param $actor
 637          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 638          * @throws \ImagickException
 639          */
 640         private static function switchContacts($receivers, $actor)
 641         {
 642                 if (empty($actor)) {
 643                         return;
 644                 }
 645
 646                 foreach ($receivers as $receiver) {
 647                         $contact = DBA::selectFirst('contact', ['id'], ['uid' => $receiver, 'network' => Protocol::OSTATUS, 'nurl' => Strings::normaliseLink($actor)]);
 648                         if (DBA::isResult($contact)) {
 649                                 self::switchContact($contact['id'], $receiver, $actor);
 650                         }
 651
 652                         $contact = DBA::selectFirst('contact', ['id'], ['uid' => $receiver, 'network' => Protocol::OSTATUS, 'alias' => [Strings::normaliseLink($actor), $actor]]);
 653                         if (DBA::isResult($contact)) {
 654                                 self::switchContact($contact['id'], $receiver, $actor);
 655                         }
 656                 }
 657         }
 658
 659         /**
 660          *
 661          *
 662          * @param       $object_data
 663          * @param array $activity
 664          *
 665          * @return mixed
 666          */
 667         private static function addActivityFields($object_data, $activity)
 668         {
 669                 if (!empty($activity['published']) && empty($object_data['published'])) {
 670                         $object_data['published'] = JsonLD::fetchElement($activity, 'as:published', '@value');
 671                 }
 672
 673                 if (!empty($activity['diaspora:guid']) && empty($object_data['diaspora:guid'])) {
 674                         $object_data['diaspora:guid'] = JsonLD::fetchElement($activity, 'diaspora:guid');
 675                 }
 676
 677                 $object_data['service'] = JsonLD::fetchElement($activity, 'as:instrument', 'as:name', '@type', 'as:Service');
 678
 679                 return $object_data;
 680         }
 681
 682         /**
 683          * Fetches the object data from external ressources if needed
 684          *
 685          * @param string  $object_id    Object ID of the the provided object
 686          * @param array   $object       The provided object array
 687          * @param boolean $trust_source Do we trust the provided object?
 688          * @param integer $uid          User ID for the signature that we use to fetch data
 689          *
 690          * @return array with trusted and valid object data
 691          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 692          * @throws \ImagickException
 693          */
 694         private static function fetchObject($object_id, $object = [], $trust_source = false, $uid = 0)
 695         {
 696                 // By fetching the type we check if the object is complete.
 697                 $type = JsonLD::fetchElement($object, '@type');
 698
 699                 if (!$trust_source || empty($type)) {
 700                         $data = ActivityPub::fetchContent($object_id, $uid);
 701                         if (!empty($data)) {
 702                                 $object = JsonLD::compact($data);
 703                                 Logger::log('Fetched content for ' . $object_id, Logger::DEBUG);
 704                         } else {
 705                                 Logger::log('Empty content for ' . $object_id . ', check if content is available locally.', Logger::DEBUG);
 706
 707                                 $item = Item::selectFirst([], ['uri' => $object_id]);
 708                                 if (!DBA::isResult($item)) {
 709                                         Logger::log('Object with url ' . $object_id . ' was not found locally.', Logger::DEBUG);
 710                                         return false;
 711                                 }
 712                                 Logger::log('Using already stored item for url ' . $object_id, Logger::DEBUG);
 713                                 $data = ActivityPub\Transmitter::createNote($item);
 714                                 $object = JsonLD::compact($data);
 715                         }
 716                 } else {
 717                         Logger::log('Using original object for url ' . $object_id, Logger::DEBUG);
 718                 }
 719
 720                 $type = JsonLD::fetchElement($object, '@type');
 721
 722                 if (empty($type)) {
 723                         Logger::log('Empty type', Logger::DEBUG);
 724                         return false;
 725                 }
 726
 727                 if (in_array($type, self::CONTENT_TYPES)) {
 728                         return self::processObject($object);
 729                 }
 730
 731                 if ($type == 'as:Announce') {
 732                         $object_id = JsonLD::fetchElement($object, 'object');
 733                         if (empty($object_id)) {
 734                                 return false;
 735                         }
 736                         return self::fetchObject($object_id, [], false, $uid);
 737                 }
 738
 739                 Logger::log('Unhandled object type: ' . $type, Logger::DEBUG);
 740         }
 741
 742         /**
 743          * Convert tags from JSON-LD format into a simplified format
 744          *
 745          * @param array $tags Tags in JSON-LD format
 746          *
 747          * @return array with tags in a simplified format
 748          */
 749         private static function processTags($tags)
 750         {
 751                 $taglist = [];
 752
 753                 if (empty($tags)) {
 754                         return [];
 755                 }
 756
 757                 foreach ($tags as $tag) {
 758                         if (empty($tag)) {
 759                                 continue;
 760                         }
 761
 762                         $element = ['type' => str_replace('as:', '', JsonLD::fetchElement($tag, '@type')),
 763                                 'href' => JsonLD::fetchElement($tag, 'as:href'),
 764                                 'name' => JsonLD::fetchElement($tag, 'as:name')];
 765
 766                         if (empty($element['type'])) {
 767                                 continue;
 768                         }
 769
 770                         $taglist[] = $element;
 771                 }
 772                 return $taglist;
 773         }
 774
 775         /**
 776          * Convert emojis from JSON-LD format into a simplified format
 777          *
 778          * @param $emojis
 779          * @return array with emojis in a simplified format
 780          */
 781         private static function processEmojis($emojis)
 782         {
 783                 $emojilist = [];
 784
 785                 if (empty($emojis)) {
 786                         return [];
 787                 }
 788
 789                 foreach ($emojis as $emoji) {
 790                         if (empty($emoji) || (JsonLD::fetchElement($emoji, '@type') != 'toot:Emoji') || empty($emoji['as:icon'])) {
 791                                 continue;
 792                         }
 793
 794                         $url = JsonLD::fetchElement($emoji['as:icon'], 'as:url');
 795                         $element = ['name' => JsonLD::fetchElement($emoji, 'as:name'),
 796                                 'href' => $url];
 797
 798                         $emojilist[] = $element;
 799                 }
 800                 return $emojilist;
 801         }
 802
 803         /**
 804          * Convert attachments from JSON-LD format into a simplified format
 805          *
 806          * @param array $attachments Attachments in JSON-LD format
 807          *
 808          * @return array with attachmants in a simplified format
 809          */
 810         private static function processAttachments($attachments)
 811         {
 812                 $attachlist = [];
 813
 814                 if (empty($attachments)) {
 815                         return [];
 816                 }
 817
 818                 foreach ($attachments as $attachment) {
 819                         if (empty($attachment)) {
 820                                 continue;
 821                         }
 822
 823                         $attachlist[] = ['type' => str_replace('as:', '', JsonLD::fetchElement($attachment, '@type')),
 824                                 'mediaType' => JsonLD::fetchElement($attachment, 'as:mediaType'),
 825                                 'name' => JsonLD::fetchElement($attachment, 'as:name'),
 826                                 'url' => JsonLD::fetchElement($attachment, 'as:url')];
 827                 }
 828                 return $attachlist;
 829         }
 830
 831         /**
 832          * Fetches data from the object part of an activity
 833          *
 834          * @param array $object
 835          *
 836          * @return array
 837          * @throws \Exception
 838          */
 839         private static function processObject($object)
 840         {
 841                 if (!JsonLD::fetchElement($object, '@id')) {
 842                         return false;
 843                 }
 844
 845                 $object_data = [];
 846                 $object_data['object_type'] = JsonLD::fetchElement($object, '@type');
 847                 $object_data['id'] = JsonLD::fetchElement($object, '@id');
 848                 $object_data['reply-to-id'] = JsonLD::fetchElement($object, 'as:inReplyTo');
 849
 850                 // An empty "id" field is translated to "./" by the compactor, so we have to check for this content
 851                 if (empty($object_data['reply-to-id']) || ($object_data['reply-to-id'] == './')) {
 852                         $object_data['reply-to-id'] = $object_data['id'];
 853                 }
 854
 855                 $object_data['published'] = JsonLD::fetchElement($object, 'as:published', '@value');
 856                 $object_data['updated'] = JsonLD::fetchElement($object, 'as:updated', '@value');
 857
 858                 if (empty($object_data['updated'])) {
 859                         $object_data['updated'] = $object_data['published'];
 860                 }
 861
 862                 if (empty($object_data['published']) && !empty($object_data['updated'])) {
 863                         $object_data['published'] = $object_data['updated'];
 864                 }
 865
 866                 $actor = JsonLD::fetchElement($object, 'as:attributedTo');
 867                 if (empty($actor)) {
 868                         $actor = JsonLD::fetchElement($object, 'as:actor');
 869                 }
 870
 871                 $object_data['diaspora:guid'] = JsonLD::fetchElement($object, 'diaspora:guid');
 872                 $object_data['diaspora:comment'] = JsonLD::fetchElement($object, 'diaspora:comment');
 873                 $object_data['diaspora:like'] = JsonLD::fetchElement($object, 'diaspora:like');
 874                 $object_data['actor'] = $object_data['author'] = $actor;
 875                 $object_data['context'] = JsonLD::fetchElement($object, 'as:context');
 876                 $object_data['conversation'] = JsonLD::fetchElement($object, 'ostatus:conversation');
 877                 $object_data['sensitive'] = JsonLD::fetchElement($object, 'as:sensitive');
 878                 $object_data['name'] = JsonLD::fetchElement($object, 'as:name');
 879                 $object_data['summary'] = JsonLD::fetchElement($object, 'as:summary');
 880                 $object_data['content'] = JsonLD::fetchElement($object, 'as:content');
 881                 $object_data['source'] = JsonLD::fetchElement($object, 'as:source', 'as:content', 'as:mediaType', 'text/bbcode');
 882                 $object_data['start-time'] = JsonLD::fetchElement($object, 'as:startTime', '@value');
 883                 $object_data['end-time'] = JsonLD::fetchElement($object, 'as:endTime', '@value');
 884                 $object_data['location'] = JsonLD::fetchElement($object, 'as:location', 'as:name', '@type', 'as:Place');
 885                 $object_data['latitude'] = JsonLD::fetchElement($object, 'as:location', 'as:latitude', '@type', 'as:Place');
 886                 $object_data['latitude'] = JsonLD::fetchElement($object_data, 'latitude', '@value');
 887                 $object_data['longitude'] = JsonLD::fetchElement($object, 'as:location', 'as:longitude', '@type', 'as:Place');
 888                 $object_data['longitude'] = JsonLD::fetchElement($object_data, 'longitude', '@value');
 889                 $object_data['attachments'] = self::processAttachments(JsonLD::fetchElementArray($object, 'as:attachment'));
 890                 $object_data['tags'] = self::processTags(JsonLD::fetchElementArray($object, 'as:tag'));
 891                 $object_data['emojis'] = self::processEmojis(JsonLD::fetchElementArray($object, 'as:tag', 'toot:Emoji'));
 892                 $object_data['generator'] = JsonLD::fetchElement($object, 'as:generator', 'as:name', '@type', 'as:Application');
 893                 $object_data['alternate-url'] = JsonLD::fetchElement($object, 'as:url');
 894
 895                 // Special treatment for Hubzilla links
 896                 if (is_array($object_data['alternate-url'])) {
 897                         $object_data['alternate-url'] = JsonLD::fetchElement($object_data['alternate-url'], 'as:href');
 898
 899                         if (!is_string($object_data['alternate-url'])) {
 900                                 $object_data['alternate-url'] = JsonLD::fetchElement($object['as:url'], 'as:href');
 901                         }
 902                 }
 903
 904                 $object_data['receiver'] = self::getReceivers($object, $object_data['actor'], $object_data['tags']);
 905
 906                 // Common object data:
 907
 908                 // Unhandled
 909                 // @context, type, actor, signature, mediaType, duration, replies, icon
 910
 911                 // Also missing: (Defined in the standard, but currently unused)
 912                 // audience, preview, endTime, startTime, image
 913
 914                 // Data in Notes:
 915
 916                 // Unhandled
 917                 // contentMap, announcement_count, announcements, context_id, likes, like_count
 918                 // inReplyToStatusId, shares, quoteUrl, statusnetConversationId
 919
 920                 // Data in video:
 921
 922                 // To-Do?
 923                 // category, licence, language, commentsEnabled
 924
 925                 // Unhandled
 926                 // views, waitTranscoding, state, support, subtitleLanguage
 927                 // likes, dislikes, shares, comments
 928
 929                 return $object_data;
 930         }
 931 }