src/Protocol/ActivityPub/Transmitter.php

   1 <?php
   2 /**
   3  * @file src/Protocol/ActivityPub/Transmitter.php
   4  */
   5 namespace Friendica\Protocol\ActivityPub;
   6
   7 use Friendica\BaseObject;
   8 use Friendica\Database\DBA;
   9 use Friendica\Core\Logger;
  10 use Friendica\Core\System;
  11 use Friendica\Util\HTTPSignature;
  12 use Friendica\Core\Protocol;
  13 use Friendica\Model\Conversation;
  14 use Friendica\Model\Contact;
  15 use Friendica\Model\APContact;
  16 use Friendica\Model\Item;
  17 use Friendica\Model\Term;
  18 use Friendica\Model\User;
  19 use Friendica\Util\DateTimeFormat;
  20 use Friendica\Content\Text\BBCode;
  21 use Friendica\Util\JsonLD;
  22 use Friendica\Util\LDSignature;
  23 use Friendica\Model\Profile;
  24 use Friendica\Object\Image;
  25 use Friendica\Protocol\ActivityPub;
  26 use Friendica\Core\Cache;
  27 use Friendica\Util\Map;
  28 use Friendica\Util\Network;
  29
  30 require_once 'include/api.php';
  31 require_once 'mod/share.php';
  32
  33 /**
  34  * @brief ActivityPub Transmitter Protocol class
  35  *
  36  * To-Do:
  37  * - Undo Announce
  38  */
  39 class Transmitter
  40 {
  41         /**
  42          * collects the lost of followers of the given owner
  43          *
  44          * @param array   $owner Owner array
  45          * @param integer $page  Page number
  46          *
  47          * @return array of owners
  48          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
  49          */
  50         public static function getFollowers($owner, $page = null)
  51         {
  52                 $condition = ['rel' => [Contact::FOLLOWER, Contact::FRIEND], 'network' => Protocol::NATIVE_SUPPORT, 'uid' => $owner['uid'],
  53                         'self' => false, 'deleted' => false, 'hidden' => false, 'archive' => false, 'pending' => false];
  54                 $count = DBA::count('contact', $condition);
  55
  56                 $data = ['@context' => ActivityPub::CONTEXT];
  57                 $data['id'] = System::baseUrl() . '/followers/' . $owner['nickname'];
  58                 $data['type'] = 'OrderedCollection';
  59                 $data['totalItems'] = $count;
  60
  61                 // When we hide our friends we will only show the pure number but don't allow more.
  62                 $profile = Profile::getByUID($owner['uid']);
  63                 if (!empty($profile['hide-friends'])) {
  64                         return $data;
  65                 }
  66
  67                 if (empty($page)) {
  68                         $data['first'] = System::baseUrl() . '/followers/' . $owner['nickname'] . '?page=1';
  69                 } else {
  70                         $list = [];
  71
  72                         $contacts = DBA::select('contact', ['url'], $condition, ['limit' => [($page - 1) * 100, 100]]);
  73                         while ($contact = DBA::fetch($contacts)) {
  74                                 $list[] = $contact['url'];
  75                         }
  76
  77                         if (!empty($list)) {
  78                                 $data['next'] = System::baseUrl() . '/followers/' . $owner['nickname'] . '?page=' . ($page + 1);
  79                         }
  80
  81                         $data['partOf'] = System::baseUrl() . '/followers/' . $owner['nickname'];
  82
  83                         $data['orderedItems'] = $list;
  84                 }
  85
  86                 return $data;
  87         }
  88
  89         /**
  90          * Create list of following contacts
  91          *
  92          * @param array   $owner Owner array
  93          * @param integer $page  Page numbe
  94          *
  95          * @return array of following contacts
  96          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
  97          */
  98         public static function getFollowing($owner, $page = null)
  99         {
 100                 $condition = ['rel' => [Contact::SHARING, Contact::FRIEND], 'network' => Protocol::NATIVE_SUPPORT, 'uid' => $owner['uid'],
 101                         'self' => false, 'deleted' => false, 'hidden' => false, 'archive' => false, 'pending' => false];
 102                 $count = DBA::count('contact', $condition);
 103
 104                 $data = ['@context' => ActivityPub::CONTEXT];
 105                 $data['id'] = System::baseUrl() . '/following/' . $owner['nickname'];
 106                 $data['type'] = 'OrderedCollection';
 107                 $data['totalItems'] = $count;
 108
 109                 // When we hide our friends we will only show the pure number but don't allow more.
 110                 $profile = Profile::getByUID($owner['uid']);
 111                 if (!empty($profile['hide-friends'])) {
 112                         return $data;
 113                 }
 114
 115                 if (empty($page)) {
 116                         $data['first'] = System::baseUrl() . '/following/' . $owner['nickname'] . '?page=1';
 117                 } else {
 118                         $list = [];
 119
 120                         $contacts = DBA::select('contact', ['url'], $condition, ['limit' => [($page - 1) * 100, 100]]);
 121                         while ($contact = DBA::fetch($contacts)) {
 122                                 $list[] = $contact['url'];
 123                         }
 124
 125                         if (!empty($list)) {
 126                                 $data['next'] = System::baseUrl() . '/following/' . $owner['nickname'] . '?page=' . ($page + 1);
 127                         }
 128
 129                         $data['partOf'] = System::baseUrl() . '/following/' . $owner['nickname'];
 130
 131                         $data['orderedItems'] = $list;
 132                 }
 133
 134                 return $data;
 135         }
 136
 137         /**
 138          * Public posts for the given owner
 139          *
 140          * @param array   $owner Owner array
 141          * @param integer $page  Page numbe
 142          *
 143          * @return array of posts
 144          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 145          * @throws \ImagickException
 146          */
 147         public static function getOutbox($owner, $page = null)
 148         {
 149                 $public_contact = Contact::getIdForURL($owner['url'], 0, true);
 150
 151                 $condition = ['uid' => 0, 'contact-id' => $public_contact, 'author-id' => $public_contact,
 152                         'private' => false, 'gravity' => [GRAVITY_PARENT, GRAVITY_COMMENT],
 153                         'deleted' => false, 'visible' => true];
 154                 $count = DBA::count('item', $condition);
 155
 156                 $data = ['@context' => ActivityPub::CONTEXT];
 157                 $data['id'] = System::baseUrl() . '/outbox/' . $owner['nickname'];
 158                 $data['type'] = 'OrderedCollection';
 159                 $data['totalItems'] = $count;
 160
 161                 if (empty($page)) {
 162                         $data['first'] = System::baseUrl() . '/outbox/' . $owner['nickname'] . '?page=1';
 163                 } else {
 164                         $list = [];
 165
 166                         $condition['parent-network'] = Protocol::NATIVE_SUPPORT;
 167
 168                         $items = Item::select(['id'], $condition, ['limit' => [($page - 1) * 20, 20], 'order' => ['created' => true]]);
 169                         while ($item = Item::fetch($items)) {
 170                                 $object = self::createObjectFromItemID($item['id']);
 171                                 unset($object['@context']);
 172                                 $list[] = $object;
 173                         }
 174
 175                         if (!empty($list)) {
 176                                 $data['next'] = System::baseUrl() . '/outbox/' . $owner['nickname'] . '?page=' . ($page + 1);
 177                         }
 178
 179                         $data['partOf'] = System::baseUrl() . '/outbox/' . $owner['nickname'];
 180
 181                         $data['orderedItems'] = $list;
 182                 }
 183
 184                 return $data;
 185         }
 186
 187         /**
 188          * Return the ActivityPub profile of the given user
 189          *
 190          * @param integer $uid User ID
 191          * @return array with profile data
 192          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 193          */
 194         public static function getProfile($uid)
 195         {
 196                 $condition = ['uid' => $uid, 'blocked' => false, 'account_expired' => false,
 197                         'account_removed' => false, 'verified' => true];
 198                 $fields = ['guid', 'nickname', 'pubkey', 'account-type', 'page-flags'];
 199                 $user = DBA::selectFirst('user', $fields, $condition);
 200                 if (!DBA::isResult($user)) {
 201                         return [];
 202                 }
 203
 204                 $fields = ['locality', 'region', 'country-name'];
 205                 $profile = DBA::selectFirst('profile', $fields, ['uid' => $uid, 'is-default' => true]);
 206                 if (!DBA::isResult($profile)) {
 207                         return [];
 208                 }
 209
 210                 $fields = ['name', 'url', 'location', 'about', 'avatar', 'photo'];
 211                 $contact = DBA::selectFirst('contact', $fields, ['uid' => $uid, 'self' => true]);
 212                 if (!DBA::isResult($contact)) {
 213                         return [];
 214                 }
 215
 216                 // On old installations and never changed contacts this might not be filled
 217                 if (empty($contact['avatar'])) {
 218                         $contact['avatar'] = $contact['photo'];
 219                 }
 220
 221                 $data = ['@context' => ActivityPub::CONTEXT];
 222                 $data['id'] = $contact['url'];
 223                 $data['diaspora:guid'] = $user['guid'];
 224                 $data['type'] = ActivityPub::ACCOUNT_TYPES[$user['account-type']];
 225                 $data['following'] = System::baseUrl() . '/following/' . $user['nickname'];
 226                 $data['followers'] = System::baseUrl() . '/followers/' . $user['nickname'];
 227                 $data['inbox'] = System::baseUrl() . '/inbox/' . $user['nickname'];
 228                 $data['outbox'] = System::baseUrl() . '/outbox/' . $user['nickname'];
 229                 $data['preferredUsername'] = $user['nickname'];
 230                 $data['name'] = $contact['name'];
 231                 $data['vcard:hasAddress'] = ['@type' => 'vcard:Home', 'vcard:country-name' => $profile['country-name'],
 232                         'vcard:region' => $profile['region'], 'vcard:locality' => $profile['locality']];
 233                 $data['summary'] = $contact['about'];
 234                 $data['url'] = $contact['url'];
 235                 $data['manuallyApprovesFollowers'] = in_array($user['page-flags'], [User::PAGE_FLAGS_NORMAL, User::PAGE_FLAGS_PRVGROUP]);
 236                 $data['publicKey'] = ['id' => $contact['url'] . '#main-key',
 237                         'owner' => $contact['url'],
 238                         'publicKeyPem' => $user['pubkey']];
 239                 $data['endpoints'] = ['sharedInbox' => System::baseUrl() . '/inbox'];
 240                 $data['icon'] = ['type' => 'Image',
 241                         'url' => $contact['avatar']];
 242
 243                 // tags: https://kitty.town/@inmysocks/100656097926961126.json
 244                 return $data;
 245         }
 246
 247         /**
 248          * Returns an array with permissions of a given item array
 249          *
 250          * @param array $item
 251          *
 252          * @return array with permissions
 253          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 254          * @throws \ImagickException
 255          */
 256         private static function fetchPermissionBlockFromConversation($item)
 257         {
 258                 if (empty($item['thr-parent'])) {
 259                         return [];
 260                 }
 261
 262                 $condition = ['item-uri' => $item['thr-parent'], 'protocol' => Conversation::PARCEL_ACTIVITYPUB];
 263                 $conversation = DBA::selectFirst('conversation', ['source'], $condition);
 264                 if (!DBA::isResult($conversation)) {
 265                         return [];
 266                 }
 267
 268                 $activity = json_decode($conversation['source'], true);
 269
 270                 $actor = JsonLD::fetchElement($activity, 'actor', 'id');
 271                 $profile = APContact::getByURL($actor);
 272
 273                 $item_profile = APContact::getByURL($item['author-link']);
 274                 $exclude[] = $item['author-link'];
 275
 276                 if ($item['gravity'] == GRAVITY_PARENT) {
 277                         $exclude[] = $item['owner-link'];
 278                 }
 279
 280                 $permissions['to'][] = $actor;
 281
 282                 foreach (['to', 'cc', 'bto', 'bcc'] as $element) {
 283                         if (empty($activity[$element])) {
 284                                 continue;
 285                         }
 286                         if (is_string($activity[$element])) {
 287                                 $activity[$element] = [$activity[$element]];
 288                         }
 289
 290                         foreach ($activity[$element] as $receiver) {
 291                                 if ($receiver == $profile['followers'] && !empty($item_profile['followers'])) {
 292                                         $permissions[$element][] = $item_profile['followers'];
 293                                 } elseif (!in_array($receiver, $exclude)) {
 294                                         $permissions[$element][] = $receiver;
 295                                 }
 296                         }
 297                 }
 298                 return $permissions;
 299         }
 300
 301         /**
 302          * Creates an array of permissions from an item thread
 303          *
 304          * @param array   $item
 305          * @param boolean $blindcopy
 306          * @param boolean $last_id
 307          *
 308          * @return array with permission data
 309          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 310          * @throws \ImagickException
 311          */
 312         private static function createPermissionBlockForItem($item, $blindcopy, $last_id = 0)
 313         {
 314                 if ($last_id == 0) {
 315                         $last_id = $item['id'];
 316                 }
 317
 318                 $always_bcc = false;
 319
 320                 // Check if we should always deliver our stuff via BCC
 321                 if (!empty($item['uid'])) {
 322                         $profile = Profile::getByUID($item['uid']);
 323                         if (!empty($profile)) {
 324                                 $always_bcc = $profile['hide-friends'];
 325                         }
 326                 }
 327
 328                 // Will be activated in a later step
 329                 // $networks = [Protocol::ACTIVITYPUB, Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS];
 330
 331                 // For now only send to these contacts:
 332                 $networks = [Protocol::ACTIVITYPUB, Protocol::OSTATUS];
 333
 334                 $data = ['to' => [], 'cc' => [], 'bcc' => []];
 335
 336                 if ($item['gravity'] == GRAVITY_PARENT) {
 337                         $actor_profile = APContact::getByURL($item['owner-link']);
 338                 } else {
 339                         $actor_profile = APContact::getByURL($item['author-link']);
 340                 }
 341
 342                 $terms = Term::tagArrayFromItemId($item['id'], TERM_MENTION);
 343
 344                 if (!$item['private']) {
 345                         $data = array_merge($data, self::fetchPermissionBlockFromConversation($item));
 346
 347                         $data['to'][] = ActivityPub::PUBLIC_COLLECTION;
 348
 349                         foreach ($terms as $term) {
 350                                 $profile = APContact::getByURL($term['url'], false);
 351                                 if (!empty($profile)) {
 352                                         $data['to'][] = $profile['url'];
 353                                 }
 354                         }
 355                 } else {
 356                         $receiver_list = Item::enumeratePermissions($item);
 357
 358                         foreach ($terms as $term) {
 359                                 $cid = Contact::getIdForURL($term['url'], $item['uid']);
 360                                 if (!empty($cid) && in_array($cid, $receiver_list)) {
 361                                         $contact = DBA::selectFirst('contact', ['url'], ['id' => $cid, 'network' => $networks]);
 362                                         if (DBA::isResult($contact) && !empty($profile = APContact::getByURL($contact['url'], false))) {
 363                                                 $data['to'][] = $profile['url'];
 364                                         }
 365                                 }
 366                         }
 367
 368                         foreach ($receiver_list as $receiver) {
 369                                 $contact = DBA::selectFirst('contact', ['url', 'hidden'], ['id' => $receiver, 'network' => $networks]);
 370                                 if (DBA::isResult($contact) && !empty($profile = APContact::getByURL($contact['url'], false))) {
 371                                         if ($contact['hidden'] || $always_bcc) {
 372                                                 $data['bcc'][] = $profile['url'];
 373                                         } else {
 374                                                 $data['cc'][] = $profile['url'];
 375                                         }
 376                                 }
 377                         }
 378                 }
 379
 380                 $parents = Item::select(['id', 'author-link', 'owner-link', 'gravity', 'uri'], ['parent' => $item['parent']]);
 381                 while ($parent = Item::fetch($parents)) {
 382                         if ($parent['gravity'] == GRAVITY_PARENT) {
 383                                 $profile = APContact::getByURL($parent['owner-link'], false);
 384                                 if (!empty($profile)) {
 385                                         if ($item['gravity'] != GRAVITY_PARENT) {
 386                                                 // Comments to forums are directed to the forum
 387                                                 // But comments to forums aren't directed to the followers collection
 388                                                 if ($profile['type'] == 'Group') {
 389                                                         $data['to'][] = $profile['url'];
 390                                                 } else {
 391                                                         $data['cc'][] = $profile['url'];
 392                                                         if (!$item['private']) {
 393                                                                 $data['cc'][] = $actor_profile['followers'];
 394                                                         }
 395                                                 }
 396                                         } else {
 397                                                 // Public thread parent post always are directed to the followes
 398                                                 if (!$item['private']) {
 399                                                         $data['cc'][] = $actor_profile['followers'];
 400                                                 }
 401                                         }
 402                                 }
 403                         }
 404
 405                         // Don't include data from future posts
 406                         if ($parent['id'] >= $last_id) {
 407                                 continue;
 408                         }
 409
 410                         $profile = APContact::getByURL($parent['author-link'], false);
 411                         if (!empty($profile)) {
 412                                 if (($profile['type'] == 'Group') || ($parent['uri'] == $item['thr-parent'])) {
 413                                         $data['to'][] = $profile['url'];
 414                                 } else {
 415                                         $data['cc'][] = $profile['url'];
 416                                 }
 417                         }
 418                 }
 419                 DBA::close($parents);
 420
 421                 $data['to'] = array_unique($data['to']);
 422                 $data['cc'] = array_unique($data['cc']);
 423                 $data['bcc'] = array_unique($data['bcc']);
 424
 425                 if (($key = array_search($item['author-link'], $data['to'])) !== false) {
 426                         unset($data['to'][$key]);
 427                 }
 428
 429                 if (($key = array_search($item['author-link'], $data['cc'])) !== false) {
 430                         unset($data['cc'][$key]);
 431                 }
 432
 433                 if (($key = array_search($item['author-link'], $data['bcc'])) !== false) {
 434                         unset($data['bcc'][$key]);
 435                 }
 436
 437                 foreach ($data['to'] as $to) {
 438                         if (($key = array_search($to, $data['cc'])) !== false) {
 439                                 unset($data['cc'][$key]);
 440                         }
 441
 442                         if (($key = array_search($to, $data['bcc'])) !== false) {
 443                                 unset($data['bcc'][$key]);
 444                         }
 445                 }
 446
 447                 foreach ($data['cc'] as $cc) {
 448                         if (($key = array_search($cc, $data['bcc'])) !== false) {
 449                                 unset($data['bcc'][$key]);
 450                         }
 451                 }
 452
 453                 $receivers = ['to' => array_values($data['to']), 'cc' => array_values($data['cc']), 'bcc' => array_values($data['bcc'])];
 454
 455                 if (!$blindcopy) {
 456                         unset($receivers['bcc']);
 457                 }
 458
 459                 return $receivers;
 460         }
 461
 462         /**
 463          * Fetches a list of inboxes of followers of a given user
 464          *
 465          * @param integer $uid      User ID
 466          * @param boolean $personal fetch personal inboxes
 467          *
 468          * @return array of follower inboxes
 469          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 470          * @throws \ImagickException
 471          */
 472         public static function fetchTargetInboxesforUser($uid, $personal = false)
 473         {
 474                 $inboxes = [];
 475
 476                 // Will be activated in a later step
 477                 // $networks = [Protocol::ACTIVITYPUB, Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS];
 478
 479                 // For now only send to these contacts:
 480                 $networks = [Protocol::ACTIVITYPUB, Protocol::OSTATUS];
 481
 482                 $condition = ['uid' => $uid, 'network' => $networks, 'archive' => false, 'pending' => false];
 483
 484                 if (!empty($uid)) {
 485                         $condition['rel'] = [Contact::FOLLOWER, Contact::FRIEND];
 486                 }
 487
 488                 $contacts = DBA::select('contact', ['url'], $condition);
 489                 while ($contact = DBA::fetch($contacts)) {
 490                         if (Network::isUrlBlocked($contact['url'])) {
 491                                 continue;
 492                         }
 493
 494                         $profile = APContact::getByURL($contact['url'], false);
 495                         if (!empty($profile)) {
 496                                 if (empty($profile['sharedinbox']) || $personal) {
 497                                         $target = $profile['inbox'];
 498                                 } else {
 499                                         $target = $profile['sharedinbox'];
 500                                 }
 501                                 $inboxes[$target] = $target;
 502                         }
 503                 }
 504                 DBA::close($contacts);
 505
 506                 return $inboxes;
 507         }
 508
 509         /**
 510          * Fetches an array of inboxes for the given item and user
 511          *
 512          * @param array   $item
 513          * @param integer $uid      User ID
 514          * @param boolean $personal fetch personal inboxes
 515          * @param integer $last_id Last item id for adding receivers
 516          *
 517          * @return array with inboxes
 518          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 519          * @throws \ImagickException
 520          */
 521         public static function fetchTargetInboxes($item, $uid, $personal = false, $last_id = 0)
 522         {
 523                 $permissions = self::createPermissionBlockForItem($item, true, $last_id);
 524                 if (empty($permissions)) {
 525                         return [];
 526                 }
 527
 528                 $inboxes = [];
 529
 530                 if ($item['gravity'] == GRAVITY_ACTIVITY) {
 531                         $item_profile = APContact::getByURL($item['author-link'], false);
 532                 } else {
 533                         $item_profile = APContact::getByURL($item['owner-link'], false);
 534                 }
 535
 536                 foreach (['to', 'cc', 'bto', 'bcc'] as $element) {
 537                         if (empty($permissions[$element])) {
 538                                 continue;
 539                         }
 540
 541                         $blindcopy = in_array($element, ['bto', 'bcc']);
 542
 543                         foreach ($permissions[$element] as $receiver) {
 544                                 if (Network::isUrlBlocked($receiver)) {
 545                                         continue;
 546                                 }
 547
 548                                 if ($receiver == $item_profile['followers']) {
 549                                         $inboxes = array_merge($inboxes, self::fetchTargetInboxesforUser($uid, $personal));
 550                                 } else {
 551                                         $profile = APContact::getByURL($receiver, false);
 552                                         if (!empty($profile)) {
 553                                                 if (empty($profile['sharedinbox']) || $personal || $blindcopy) {
 554                                                         $target = $profile['inbox'];
 555                                                 } else {
 556                                                         $target = $profile['sharedinbox'];
 557                                                 }
 558                                                 $inboxes[$target] = $target;
 559                                         }
 560                                 }
 561                         }
 562                 }
 563
 564                 return $inboxes;
 565         }
 566
 567         /**
 568          * Returns the activity type of a given item
 569          *
 570          * @param array $item
 571          *
 572          * @return string with activity type
 573          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 574          * @throws \ImagickException
 575          */
 576         private static function getTypeOfItem($item)
 577         {
 578                 $reshared = false;
 579
 580                 // Only check for a reshare, if it is a real reshare and no quoted reshare
 581                 if (strpos($item['body'], "[share") === 0) {
 582                         $announce = api_share_as_retweet($item);
 583                         $reshared = !empty($announce['plink']);
 584                 }
 585
 586                 if ($reshared) {
 587                         $type = 'Announce';
 588                 } elseif ($item['verb'] == ACTIVITY_POST) {
 589                         if ($item['created'] == $item['edited']) {
 590                                 $type = 'Create';
 591                         } else {
 592                                 $type = 'Update';
 593                         }
 594                 } elseif ($item['verb'] == ACTIVITY_LIKE) {
 595                         $type = 'Like';
 596                 } elseif ($item['verb'] == ACTIVITY_DISLIKE) {
 597                         $type = 'Dislike';
 598                 } elseif ($item['verb'] == ACTIVITY_ATTEND) {
 599                         $type = 'Accept';
 600                 } elseif ($item['verb'] == ACTIVITY_ATTENDNO) {
 601                         $type = 'Reject';
 602                 } elseif ($item['verb'] == ACTIVITY_ATTENDMAYBE) {
 603                         $type = 'TentativeAccept';
 604                 } elseif ($item['verb'] == ACTIVITY_FOLLOW) {
 605                         $type = 'Follow';
 606                 } else {
 607                         $type = '';
 608                 }
 609
 610                 return $type;
 611         }
 612
 613         /**
 614          * Creates the activity or fetches it from the cache
 615          *
 616          * @param integer $item_id
 617          * @param boolean $force Force new cache entry
 618          *
 619          * @return array with the activity
 620          * @throws \Exception
 621          */
 622         public static function createCachedActivityFromItem($item_id, $force = false)
 623         {
 624                 $cachekey = 'APDelivery:createActivity:' . $item_id;
 625
 626                 if (!$force) {
 627                         $data = Cache::get($cachekey);
 628                         if (!is_null($data)) {
 629                                 return $data;
 630                         }
 631                 }
 632
 633                 $data = ActivityPub\Transmitter::createActivityFromItem($item_id);
 634
 635                 Cache::set($cachekey, $data, Cache::QUARTER_HOUR);
 636                 return $data;
 637         }
 638
 639         /**
 640          * Creates an activity array for a given item id
 641          *
 642          * @param integer $item_id
 643          * @param boolean $object_mode Is the activity item is used inside another object?
 644          *
 645          * @return array of activity
 646          * @throws \Exception
 647          */
 648         public static function createActivityFromItem($item_id, $object_mode = false)
 649         {
 650                 $item = Item::selectFirst([], ['id' => $item_id, 'parent-network' => Protocol::NATIVE_SUPPORT]);
 651
 652                 if (!DBA::isResult($item)) {
 653                         return false;
 654                 }
 655
 656                 if ($item['wall']) {
 657                         $owner = User::getOwnerDataById($item['uid']);
 658                         if (($owner['account-type'] == User::ACCOUNT_TYPE_COMMUNITY) && ($item['author-link'] != $owner['url'])) {
 659                                 $type = 'Announce';
 660
 661                                 // Disguise forum posts as reshares. Will later be converted to a real announce
 662                                 $item['body'] = share_header($item['author-name'], $item['author-link'], $item['author-avatar'],
 663                                         $item['guid'], $item['created'], $item['plink']) . $item['body'] . '[/share]';
 664                         }
 665                 }
 666
 667                 if (empty($type)) {
 668                         $condition = ['item-uri' => $item['uri'], 'protocol' => Conversation::PARCEL_ACTIVITYPUB];
 669                         $conversation = DBA::selectFirst('conversation', ['source'], $condition);
 670                         if (DBA::isResult($conversation)) {
 671                                 $data = json_decode($conversation['source']);
 672                                 if (!empty($data)) {
 673                                         return $data;
 674                                 }
 675                         }
 676
 677                         $type = self::getTypeOfItem($item);
 678                 }
 679
 680                 if (!$object_mode) {
 681                         $data = ['@context' => ActivityPub::CONTEXT];
 682
 683                         if ($item['deleted'] && ($item['gravity'] == GRAVITY_ACTIVITY)) {
 684                                 $type = 'Undo';
 685                         } elseif ($item['deleted']) {
 686                                 $type = 'Delete';
 687                         }
 688                 } else {
 689                         $data = [];
 690                 }
 691
 692                 $data['id'] = $item['uri'] . '#' . $type;
 693                 $data['type'] = $type;
 694                 $data['actor'] = $item['owner-link'];
 695
 696                 $data['published'] = DateTimeFormat::utc($item['created'] . '+00:00', DateTimeFormat::ATOM);
 697
 698                 $data['instrument'] = ['type' => 'Service', 'name' => BaseObject::getApp()->getUserAgent()];
 699
 700                 $data = array_merge($data, self::createPermissionBlockForItem($item, false));
 701
 702                 if (in_array($data['type'], ['Create', 'Update', 'Delete'])) {
 703                         $data['object'] = self::createNote($item);
 704                 } elseif ($data['type'] == 'Announce') {
 705                         $data = self::createAnnounce($item, $data);
 706                 } elseif ($data['type'] == 'Follow') {
 707                         $data['object'] = $item['parent-uri'];
 708                 } elseif ($data['type'] == 'Undo') {
 709                         $data['object'] = self::createActivityFromItem($item_id, true);
 710                 } else {
 711                         $data['diaspora:guid'] = $item['guid'];
 712                         if (!empty($item['signed_text'])) {
 713                                 $data['diaspora:like'] = $item['signed_text'];
 714                         }
 715                         $data['object'] = $item['thr-parent'];
 716                 }
 717
 718                 if (!empty($item['contact-uid'])) {
 719                         $uid = $item['contact-uid'];
 720                 } else {
 721                         $uid = $item['uid'];
 722                 }
 723
 724                 $owner = User::getOwnerDataById($uid);
 725
 726                 if (!$object_mode && !empty($owner)) {
 727                         return LDSignature::sign($data, $owner);
 728                 } else {
 729                         return $data;
 730                 }
 731
 732                 /// @todo Create "conversation" entry
 733         }
 734
 735         /**
 736          * Creates an object array for a given item id
 737          *
 738          * @param integer $item_id
 739          *
 740          * @return array with the object data
 741          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 742          * @throws \ImagickException
 743          */
 744         public static function createObjectFromItemID($item_id)
 745         {
 746                 $item = Item::selectFirst([], ['id' => $item_id, 'parent-network' => Protocol::NATIVE_SUPPORT]);
 747
 748                 if (!DBA::isResult($item)) {
 749                         return false;
 750                 }
 751
 752                 $data = ['@context' => ActivityPub::CONTEXT];
 753                 $data = array_merge($data, self::createNote($item));
 754
 755                 return $data;
 756         }
 757
 758         /**
 759          * Creates a location entry for a given item array
 760          *
 761          * @param array $item
 762          *
 763          * @return array with location array
 764          */
 765         private static function createLocation($item)
 766         {
 767                 $location = ['type' => 'Place'];
 768
 769                 if (!empty($item['location'])) {
 770                         $location['name'] = $item['location'];
 771                 }
 772
 773                 $coord = [];
 774
 775                 if (empty($item['coord'])) {
 776                         $coord = Map::getCoordinates($item['location']);
 777                 } else {
 778                         $coords = explode(' ', $item['coord']);
 779                         if (count($coords) == 2) {
 780                                 $coord = ['lat' => $coords[0], 'lon' => $coords[1]];
 781                         }
 782                 }
 783
 784                 if (!empty($coord['lat']) && !empty($coord['lon'])) {
 785                         $location['latitude'] = $coord['lat'];
 786                         $location['longitude'] = $coord['lon'];
 787                 }
 788
 789                 return $location;
 790         }
 791
 792         /**
 793          * Returns a tag array for a given item array
 794          *
 795          * @param array $item
 796          *
 797          * @return array of tags
 798          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 799          */
 800         private static function createTagList($item)
 801         {
 802                 $tags = [];
 803
 804                 $terms = Term::tagArrayFromItemId($item['id']);
 805                 foreach ($terms as $term) {
 806                         if ($term['type'] == TERM_HASHTAG) {
 807                                 $url = System::baseUrl() . '/search?tag=' . urlencode($term['term']);
 808                                 $tags[] = ['type' => 'Hashtag', 'href' => $url, 'name' => '#' . $term['term']];
 809                         } elseif ($term['type'] == TERM_MENTION) {
 810                                 $contact = Contact::getDetailsByURL($term['url']);
 811                                 if (!empty($contact['addr'])) {
 812                                         $mention = '@' . $contact['addr'];
 813                                 } else {
 814                                         $mention = '@' . $term['url'];
 815                                 }
 816
 817                                 $tags[] = ['type' => 'Mention', 'href' => $term['url'], 'name' => $mention];
 818                         }
 819                 }
 820                 return $tags;
 821         }
 822
 823         /**
 824          * Adds attachment data to the JSON document
 825          *
 826          * @param array  $item Data of the item that is to be posted
 827          * @param string $type Object type
 828          *
 829          * @return array with attachment data
 830          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 831          */
 832         private static function createAttachmentList($item, $type)
 833         {
 834                 $attachments = [];
 835
 836                 $arr = explode('[/attach],', $item['attach']);
 837                 if (count($arr)) {
 838                         foreach ($arr as $r) {
 839                                 $matches = false;
 840                                 $cnt = preg_match('|\[attach\]href=\"(.*?)\" length=\"(.*?)\" type=\"(.*?)\" title=\"(.*?)\"|', $r, $matches);
 841                                 if ($cnt) {
 842                                         $attributes = ['type' => 'Document',
 843                                                         'mediaType' => $matches[3],
 844                                                         'url' => $matches[1],
 845                                                         'name' => null];
 846
 847                                         if (trim($matches[4]) != '') {
 848                                                 $attributes['name'] = trim($matches[4]);
 849                                         }
 850
 851                                         $attachments[] = $attributes;
 852                                 }
 853                         }
 854                 }
 855
 856                 if ($type != 'Note') {
 857                         return $attachments;
 858                 }
 859
 860                 // Simplify image codes
 861                 $body = preg_replace("/\[img\=([0-9]*)x([0-9]*)\](.*?)\[\/img\]/ism", '[img]$3[/img]', $item['body']);
 862
 863                 // Grab all pictures and create attachments out of them
 864                 if (preg_match_all("/\[img\]([^\[\]]*)\[\/img\]/Usi", $body, $pictures)) {
 865                         foreach ($pictures[1] as $picture) {
 866                                 $imgdata = Image::getInfoFromURL($picture);
 867                                 if ($imgdata) {
 868                                         $attachments[] = ['type' => 'Document',
 869                                                 'mediaType' => $imgdata['mime'],
 870                                                 'url' => $picture,
 871                                                 'name' => null];
 872                                 }
 873                         }
 874                 }
 875
 876                 return $attachments;
 877         }
 878
 879         /**
 880          * @brief Callback function to replace a Friendica style mention in a mention that is used on AP
 881          *
 882          * @param array $match Matching values for the callback
 883          * @return string Replaced mention
 884          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 885          */
 886         private static function mentionCallback($match)
 887         {
 888                 if (empty($match[1])) {
 889                         return;
 890                 }
 891
 892                 $data = Contact::getDetailsByURL($match[1]);
 893                 if (empty($data) || empty($data['nick'])) {
 894                         return;
 895                 }
 896
 897                 return '@[url=' . $data['url'] . ']' . $data['nick'] . '[/url]';
 898         }
 899
 900         /**
 901          * Remove image elements and replaces them with links to the image
 902          *
 903          * @param string $body
 904          *
 905          * @return string with replaced elements
 906          */
 907         private static function removePictures($body)
 908         {
 909                 // Simplify image codes
 910                 $body = preg_replace("/\[img\=([0-9]*)x([0-9]*)\](.*?)\[\/img\]/ism", '[img]$3[/img]', $body);
 911
 912                 $body = preg_replace("/\[url=([^\[\]]*)\]\[img\](.*)\[\/img\]\[\/url\]/Usi", '[url]$1[/url]', $body);
 913                 $body = preg_replace("/\[img\]([^\[\]]*)\[\/img\]/Usi", '[url]$1[/url]', $body);
 914
 915                 return $body;
 916         }
 917
 918         /**
 919          * Fetches the "context" value for a givem item array from the "conversation" table
 920          *
 921          * @param array $item
 922          *
 923          * @return string with context url
 924          * @throws \Exception
 925          */
 926         private static function fetchContextURLForItem($item)
 927         {
 928                 $conversation = DBA::selectFirst('conversation', ['conversation-href', 'conversation-uri'], ['item-uri' => $item['parent-uri']]);
 929                 if (DBA::isResult($conversation) && !empty($conversation['conversation-href'])) {
 930                         $context_uri = $conversation['conversation-href'];
 931                 } elseif (DBA::isResult($conversation) && !empty($conversation['conversation-uri'])) {
 932                         $context_uri = $conversation['conversation-uri'];
 933                 } else {
 934                         $context_uri = $item['parent-uri'] . '#context';
 935                 }
 936                 return $context_uri;
 937         }
 938
 939         /**
 940          * Returns if the post contains sensitive content ("nsfw")
 941          *
 942          * @param integer $item_id
 943          *
 944          * @return boolean
 945          * @throws \Exception
 946          */
 947         private static function isSensitive($item_id)
 948         {
 949                 $condition = ['otype' => TERM_OBJ_POST, 'oid' => $item_id, 'type' => TERM_HASHTAG, 'term' => 'nsfw'];
 950                 return DBA::exists('term', $condition);
 951         }
 952
 953         /**
 954          * Creates event data
 955          *
 956          * @param array $item
 957          *
 958          * @return array with the event data
 959          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 960          */
 961         public static function createEvent($item)
 962         {
 963                 $event = [];
 964                 $event['name'] = $item['event-summary'];
 965                 $event['content'] = BBCode::convert($item['event-desc'], false, 7);
 966                 $event['startTime'] = DateTimeFormat::utc($item['event-start'] . '+00:00', DateTimeFormat::ATOM);
 967
 968                 if (!$item['event-nofinish']) {
 969                         $event['endTime'] = DateTimeFormat::utc($item['event-finish'] . '+00:00', DateTimeFormat::ATOM);
 970                 }
 971
 972                 if (!empty($item['event-location'])) {
 973                         $item['location'] = $item['event-location'];
 974                         $event['location'] = self::createLocation($item);
 975                 }
 976
 977                 return $event;
 978         }
 979
 980         /**
 981          * Creates a note/article object array
 982          *
 983          * @param array $item
 984          *
 985          * @return array with the object data
 986          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 987          * @throws \ImagickException
 988          */
 989         public static function createNote($item)
 990         {
 991                 if ($item['event-type'] == 'event') {
 992                         $type = 'Event';
 993                 } elseif (!empty($item['title'])) {
 994                         $type = 'Article';
 995                 } else {
 996                         $type = 'Note';
 997                 }
 998
 999                 if ($item['deleted']) {
1000                         $type = 'Tombstone';
1001                 }
1002
1003                 $data = [];
1004                 $data['id'] = $item['uri'];
1005                 $data['type'] = $type;
1006
1007                 if ($item['deleted']) {
1008                         return $data;
1009                 }
1010
1011                 $data['summary'] = null; // Ignore by now
1012
1013                 if ($item['uri'] != $item['thr-parent']) {
1014                         $data['inReplyTo'] = $item['thr-parent'];
1015                 } else {
1016                         $data['inReplyTo'] = null;
1017                 }
1018
1019                 $data['diaspora:guid'] = $item['guid'];
1020                 $data['published'] = DateTimeFormat::utc($item['created'] . '+00:00', DateTimeFormat::ATOM);
1021
1022                 if ($item['created'] != $item['edited']) {
1023                         $data['updated'] = DateTimeFormat::utc($item['edited'] . '+00:00', DateTimeFormat::ATOM);
1024                 }
1025
1026                 $data['url'] = $item['plink'];
1027                 $data['attributedTo'] = $item['author-link'];
1028                 $data['sensitive'] = self::isSensitive($item['id']);
1029                 $data['context'] = self::fetchContextURLForItem($item);
1030
1031                 if (!empty($item['title'])) {
1032                         $data['name'] = BBCode::toPlaintext($item['title'], false);
1033                 }
1034
1035                 $body = $item['body'];
1036
1037                 if ($type == 'Note') {
1038                         $body = self::removePictures($body);
1039                 }
1040
1041                 if ($type == 'Event') {
1042                         $data = array_merge($data, self::createEvent($item));
1043                 } else {
1044                         $regexp = "/[@!]\[url\=([^\[\]]*)\].*?\[\/url\]/ism";
1045                         $body = preg_replace_callback($regexp, ['self', 'mentionCallback'], $body);
1046
1047                         $data['content'] = BBCode::convert($body, false, 7);
1048                 }
1049
1050                 $data['source'] = ['content' => $item['body'], 'mediaType' => "text/bbcode"];
1051
1052                 if (!empty($item['signed_text']) && ($item['uri'] != $item['thr-parent'])) {
1053                         $data['diaspora:comment'] = $item['signed_text'];
1054                 }
1055
1056                 $data['attachment'] = self::createAttachmentList($item, $type);
1057                 $data['tag'] = self::createTagList($item);
1058
1059                 if (empty($data['location']) && (!empty($item['coord']) || !empty($item['location']))) {
1060                         $data['location'] = self::createLocation($item);
1061                 }
1062
1063                 if (!empty($item['app'])) {
1064                         $data['generator'] = ['type' => 'Application', 'name' => $item['app']];
1065                 }
1066
1067                 $data = array_merge($data, self::createPermissionBlockForItem($item, false));
1068
1069                 return $data;
1070         }
1071
1072         /**
1073          * Creates an announce object entry
1074          *
1075          * @param array $item
1076          * @param array $data activity data
1077          *
1078          * @return array with activity data
1079          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1080          * @throws \ImagickException
1081          */
1082         private static function createAnnounce($item, $data)
1083         {
1084                 $announce = api_share_as_retweet($item);
1085                 if (empty($announce['plink'])) {
1086                         $data['type'] = 'Create';
1087                         $data['object'] = self::createNote($item);
1088                         return $data;
1089                 }
1090
1091                 // Fetch the original id of the object
1092                 $activity = ActivityPub::fetchContent($announce['plink'], $item['uid']);
1093                 if (!empty($activity)) {
1094                         $ldactivity = JsonLD::compact($activity);
1095                         $id = JsonLD::fetchElement($ldactivity, '@id');
1096                         if (!empty($id)) {
1097                                 $data['object'] = $id;
1098                                 return $data;
1099                         }
1100                 }
1101
1102                 $data['type'] = 'Create';
1103                 $data['object'] = self::createNote($item);
1104                 return $data;
1105         }
1106
1107         /**
1108          * Creates an activity id for a given contact id
1109          *
1110          * @param integer $cid Contact ID of target
1111          *
1112          * @return bool|string activity id
1113          */
1114         public static function activityIDFromContact($cid)
1115         {
1116                 $contact = DBA::selectFirst('contact', ['uid', 'id', 'created'], ['id' => $cid]);
1117                 if (!DBA::isResult($contact)) {
1118                         return false;
1119                 }
1120
1121                 $hash = hash('ripemd128', $contact['uid'].'-'.$contact['id'].'-'.$contact['created']);
1122                 $uuid = substr($hash, 0, 8). '-' . substr($hash, 8, 4) . '-' . substr($hash, 12, 4) . '-' . substr($hash, 16, 4) . '-' . substr($hash, 20, 12);
1123                 return System::baseUrl() . '/activity/' . $uuid;
1124         }
1125
1126         /**
1127          * Transmits a contact suggestion to a given inbox
1128          *
1129          * @param integer $uid           User ID
1130          * @param string  $inbox         Target inbox
1131          * @param integer $suggestion_id Suggestion ID
1132          *
1133          * @return boolean was the transmission successful?
1134          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1135          */
1136         public static function sendContactSuggestion($uid, $inbox, $suggestion_id)
1137         {
1138                 $owner = User::getOwnerDataById($uid);
1139
1140                 $suggestion = DBA::selectFirst('fsuggest', ['url', 'note', 'created'], ['id' => $suggestion_id]);
1141
1142                 $data = ['@context' => ActivityPub::CONTEXT,
1143                         'id' => System::baseUrl() . '/activity/' . System::createGUID(),
1144                         'type' => 'Announce',
1145                         'actor' => $owner['url'],
1146                         'object' => $suggestion['url'],
1147                         'content' => $suggestion['note'],
1148                         'instrument' => ['type' => 'Service', 'name' => BaseObject::getApp()->getUserAgent()],
1149                         'to' => [ActivityPub::PUBLIC_COLLECTION],
1150                         'cc' => []];
1151
1152                 $signed = LDSignature::sign($data, $owner);
1153
1154                 Logger::log('Deliver profile deletion for user ' . $uid . ' to ' . $inbox . ' via ActivityPub', Logger::DEBUG);
1155                 return HTTPSignature::transmit($signed, $inbox, $uid);
1156         }
1157
1158         /**
1159          * Transmits a profile relocation to a given inbox
1160          *
1161          * @param integer $uid   User ID
1162          * @param string  $inbox Target inbox
1163          *
1164          * @return boolean was the transmission successful?
1165          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1166          */
1167         public static function sendProfileRelocation($uid, $inbox)
1168         {
1169                 $owner = User::getOwnerDataById($uid);
1170
1171                 $data = ['@context' => ActivityPub::CONTEXT,
1172                         'id' => System::baseUrl() . '/activity/' . System::createGUID(),
1173                         'type' => 'dfrn:relocate',
1174                         'actor' => $owner['url'],
1175                         'object' => $owner['url'],
1176                         'published' => DateTimeFormat::utcNow(DateTimeFormat::ATOM),
1177                         'instrument' => ['type' => 'Service', 'name' => BaseObject::getApp()->getUserAgent()],
1178                         'to' => [ActivityPub::PUBLIC_COLLECTION],
1179                         'cc' => []];
1180
1181                 $signed = LDSignature::sign($data, $owner);
1182
1183                 Logger::log('Deliver profile relocation for user ' . $uid . ' to ' . $inbox . ' via ActivityPub', Logger::DEBUG);
1184                 return HTTPSignature::transmit($signed, $inbox, $uid);
1185         }
1186
1187         /**
1188          * Transmits a profile deletion to a given inbox
1189          *
1190          * @param integer $uid   User ID
1191          * @param string  $inbox Target inbox
1192          *
1193          * @return boolean was the transmission successful?
1194          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1195          */
1196         public static function sendProfileDeletion($uid, $inbox)
1197         {
1198                 $owner = User::getOwnerDataById($uid);
1199
1200                 $data = ['@context' => ActivityPub::CONTEXT,
1201                         'id' => System::baseUrl() . '/activity/' . System::createGUID(),
1202                         'type' => 'Delete',
1203                         'actor' => $owner['url'],
1204                         'object' => $owner['url'],
1205                         'published' => DateTimeFormat::utcNow(DateTimeFormat::ATOM),
1206                         'instrument' => ['type' => 'Service', 'name' => BaseObject::getApp()->getUserAgent()],
1207                         'to' => [ActivityPub::PUBLIC_COLLECTION],
1208                         'cc' => []];
1209
1210                 $signed = LDSignature::sign($data, $owner);
1211
1212                 Logger::log('Deliver profile deletion for user ' . $uid . ' to ' . $inbox . ' via ActivityPub', Logger::DEBUG);
1213                 return HTTPSignature::transmit($signed, $inbox, $uid);
1214         }
1215
1216         /**
1217          * Transmits a profile change to a given inbox
1218          *
1219          * @param integer $uid   User ID
1220          * @param string  $inbox Target inbox
1221          *
1222          * @return boolean was the transmission successful?
1223          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1224          * @throws \ImagickException
1225          */
1226         public static function sendProfileUpdate($uid, $inbox)
1227         {
1228                 $owner = User::getOwnerDataById($uid);
1229                 $profile = APContact::getByURL($owner['url']);
1230
1231                 $data = ['@context' => ActivityPub::CONTEXT,
1232                         'id' => System::baseUrl() . '/activity/' . System::createGUID(),
1233                         'type' => 'Update',
1234                         'actor' => $owner['url'],
1235                         'object' => self::getProfile($uid),
1236                         'published' => DateTimeFormat::utcNow(DateTimeFormat::ATOM),
1237                         'instrument' => ['type' => 'Service', 'name' => BaseObject::getApp()->getUserAgent()],
1238                         'to' => [$profile['followers']],
1239                         'cc' => []];
1240
1241                 $signed = LDSignature::sign($data, $owner);
1242
1243                 Logger::log('Deliver profile update for user ' . $uid . ' to ' . $inbox . ' via ActivityPub', Logger::DEBUG);
1244                 return HTTPSignature::transmit($signed, $inbox, $uid);
1245         }
1246
1247         /**
1248          * Transmits a given activity to a target
1249          *
1250          * @param string  $activity Type name
1251          * @param string  $target   Target profile
1252          * @param integer $uid      User ID
1253          * @return bool
1254          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1255          * @throws \ImagickException
1256          * @throws \Exception
1257          */
1258         public static function sendActivity($activity, $target, $uid, $id = '')
1259         {
1260                 $profile = APContact::getByURL($target);
1261
1262                 $owner = User::getOwnerDataById($uid);
1263
1264                 if (empty($id)) {
1265                         $id = System::baseUrl() . '/activity/' . System::createGUID();
1266                 }
1267
1268                 $data = ['@context' => ActivityPub::CONTEXT,
1269                         'id' => $id,
1270                         'type' => $activity,
1271                         'actor' => $owner['url'],
1272                         'object' => $profile['url'],
1273                         'instrument' => ['type' => 'Service', 'name' => BaseObject::getApp()->getUserAgent()],
1274                         'to' => [$profile['url']]];
1275
1276                 Logger::log('Sending activity ' . $activity . ' to ' . $target . ' for user ' . $uid, Logger::DEBUG);
1277
1278                 $signed = LDSignature::sign($data, $owner);
1279                 return HTTPSignature::transmit($signed, $profile['inbox'], $uid);
1280         }
1281
1282         /**
1283          * Transmits a "follow object" activity to a target
1284          * This is a preparation for sending automated "follow" requests when receiving "Announce" messages
1285          *
1286          * @param string  $object Object URL
1287          * @param string  $target Target profile
1288          * @param integer $uid    User ID
1289          * @return bool
1290          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1291          * @throws \ImagickException
1292          * @throws \Exception
1293          */
1294         public static function sendFollowObject($object, $target, $uid)
1295         {
1296                 $profile = APContact::getByURL($target);
1297
1298                 $owner = User::getOwnerDataById($uid);
1299
1300                 $data = ['@context' => ActivityPub::CONTEXT,
1301                         'id' => System::baseUrl() . '/activity/' . System::createGUID(),
1302                         'type' => 'Follow',
1303                         'actor' => $owner['url'],
1304                         'object' => $object,
1305                         'instrument' => ['type' => 'Service', 'name' => BaseObject::getApp()->getUserAgent()],
1306                         'to' => [$profile['url']]];
1307
1308                 Logger::log('Sending follow ' . $object . ' to ' . $target . ' for user ' . $uid, Logger::DEBUG);
1309
1310                 $signed = LDSignature::sign($data, $owner);
1311                 return HTTPSignature::transmit($signed, $profile['inbox'], $uid);
1312         }
1313
1314         /**
1315          * Transmit a message that the contact request had been accepted
1316          *
1317          * @param string  $target Target profile
1318          * @param         $id
1319          * @param integer $uid    User ID
1320          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1321          * @throws \ImagickException
1322          */
1323         public static function sendContactAccept($target, $id, $uid)
1324         {
1325                 $profile = APContact::getByURL($target);
1326
1327                 $owner = User::getOwnerDataById($uid);
1328                 $data = ['@context' => ActivityPub::CONTEXT,
1329                         'id' => System::baseUrl() . '/activity/' . System::createGUID(),
1330                         'type' => 'Accept',
1331                         'actor' => $owner['url'],
1332                         'object' => ['id' => $id, 'type' => 'Follow',
1333                                 'actor' => $profile['url'],
1334                                 'object' => $owner['url']],
1335                         'instrument' => ['type' => 'Service', 'name' => BaseObject::getApp()->getUserAgent()],
1336                         'to' => [$profile['url']]];
1337
1338                 Logger::log('Sending accept to ' . $target . ' for user ' . $uid . ' with id ' . $id, Logger::DEBUG);
1339
1340                 $signed = LDSignature::sign($data, $owner);
1341                 HTTPSignature::transmit($signed, $profile['inbox'], $uid);
1342         }
1343
1344         /**
1345          * Reject a contact request or terminates the contact relation
1346          *
1347          * @param string  $target Target profile
1348          * @param         $id
1349          * @param integer $uid    User ID
1350          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1351          * @throws \ImagickException
1352          */
1353         public static function sendContactReject($target, $id, $uid)
1354         {
1355                 $profile = APContact::getByURL($target);
1356
1357                 $owner = User::getOwnerDataById($uid);
1358                 $data = ['@context' => ActivityPub::CONTEXT,
1359                         'id' => System::baseUrl() . '/activity/' . System::createGUID(),
1360                         'type' => 'Reject',
1361                         'actor' => $owner['url'],
1362                         'object' => ['id' => $id, 'type' => 'Follow',
1363                                 'actor' => $profile['url'],
1364                                 'object' => $owner['url']],
1365                         'instrument' => ['type' => 'Service', 'name' => BaseObject::getApp()->getUserAgent()],
1366                         'to' => [$profile['url']]];
1367
1368                 Logger::log('Sending reject to ' . $target . ' for user ' . $uid . ' with id ' . $id, Logger::DEBUG);
1369
1370                 $signed = LDSignature::sign($data, $owner);
1371                 HTTPSignature::transmit($signed, $profile['inbox'], $uid);
1372         }
1373
1374         /**
1375          * Transmits a message that we don't want to follow this contact anymore
1376          *
1377          * @param string  $target Target profile
1378          * @param integer $uid    User ID
1379          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1380          * @throws \ImagickException
1381          * @throws \Exception
1382          */
1383         public static function sendContactUndo($target, $cid, $uid)
1384         {
1385                 $profile = APContact::getByURL($target);
1386
1387                 $object_id = self::activityIDFromContact($cid);
1388                 if (empty($object_id)) {
1389                         return;
1390                 }
1391
1392                 $id = System::baseUrl() . '/activity/' . System::createGUID();
1393
1394                 $owner = User::getOwnerDataById($uid);
1395                 $data = ['@context' => ActivityPub::CONTEXT,
1396                         'id' => $id,
1397                         'type' => 'Undo',
1398                         'actor' => $owner['url'],
1399                         'object' => ['id' => $object_id, 'type' => 'Follow',
1400                                 'actor' => $owner['url'],
1401                                 'object' => $profile['url']],
1402                         'instrument' => ['type' => 'Service', 'name' => BaseObject::getApp()->getUserAgent()],
1403                         'to' => [$profile['url']]];
1404
1405                 Logger::log('Sending undo to ' . $target . ' for user ' . $uid . ' with id ' . $id, Logger::DEBUG);
1406
1407                 $signed = LDSignature::sign($data, $owner);
1408                 HTTPSignature::transmit($signed, $profile['inbox'], $uid);
1409         }
1410 }