src/Model/GServer.php

   1 <?php
   2 /**
   3  * @copyright Copyright (C) 2010-2023, the Friendica project
   4  *
   5  * @license GNU AGPL version 3 or any later version
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU Affero General Public License as
   9  * published by the Free Software Foundation, either version 3 of the
  10  * License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU Affero General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Affero General Public License
  18  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  19  *
  20  */
  21
  22 namespace Friendica\Model;
  23
  24 use DOMDocument;
  25 use DOMXPath;
  26 use Exception;
  27 use Friendica\Core\Logger;
  28 use Friendica\Core\Protocol;
  29 use Friendica\Core\System;
  30 use Friendica\Core\Worker;
  31 use Friendica\Database\Database;
  32 use Friendica\Database\DBA;
  33 use Friendica\DI;
  34 use Friendica\Module\Register;
  35 use Friendica\Network\HTTPClient\Client\HttpClientAccept;
  36 use Friendica\Network\HTTPClient\Client\HttpClientOptions;
  37 use Friendica\Network\HTTPClient\Capability\ICanHandleHttpResponses;
  38 use Friendica\Network\Probe;
  39 use Friendica\Protocol\ActivityPub;
  40 use Friendica\Protocol\Relay;
  41 use Friendica\Util\DateTimeFormat;
  42 use Friendica\Util\JsonLD;
  43 use Friendica\Util\Network;
  44 use Friendica\Util\Strings;
  45 use Friendica\Util\XML;
  46 use Friendica\Network\HTTPException;
  47 use Friendica\Worker\UpdateGServer;
  48 use GuzzleHttp\Psr7\Uri;
  49 use Psr\Http\Message\UriInterface;
  50
  51 /**
  52  * This class handles GServer related functions
  53  */
  54 class GServer
  55 {
  56         // Directory types
  57         const DT_NONE = 0;
  58         const DT_POCO = 1;
  59         const DT_MASTODON = 2;
  60
  61         // Methods to detect server types
  62
  63         // Non endpoint specific methods
  64         const DETECT_MANUAL = 0;
  65         const DETECT_HEADER = 1;
  66         const DETECT_BODY = 2;
  67         const DETECT_HOST_META = 3;
  68         const DETECT_CONTACTS = 4;
  69         const DETECT_AP_ACTOR = 5;
  70         const DETECT_AP_COLLECTION = 6;
  71
  72         const DETECT_UNSPECIFIC = [self::DETECT_MANUAL, self::DETECT_HEADER, self::DETECT_BODY, self::DETECT_HOST_META, self::DETECT_CONTACTS, self::DETECT_AP_ACTOR];
  73
  74         // Implementation specific endpoints
  75         // @todo Possibly add Lemmy detection via the endpoint /api/v3/site
  76         const DETECT_FRIENDIKA = 10;
  77         const DETECT_FRIENDICA = 11;
  78         const DETECT_STATUSNET = 12;
  79         const DETECT_GNUSOCIAL = 13;
  80         const DETECT_CONFIG_JSON = 14; // Statusnet, GNU Social, Older Hubzilla/Redmatrix
  81         const DETECT_SITEINFO_JSON = 15; // Newer Hubzilla
  82         const DETECT_MASTODON_API = 16;
  83         const DETECT_STATUS_PHP = 17; // Nextcloud
  84         const DETECT_V1_CONFIG = 18;
  85         const DETECT_PUMPIO = 19; // Deprecated
  86         const DETECT_SYSTEM_ACTOR = 20; // Mistpark, Osada, Roadhouse, Zap
  87
  88         // Standardized endpoints
  89         const DETECT_STATISTICS_JSON = 100;
  90         const DETECT_NODEINFO_1 = 101;
  91         const DETECT_NODEINFO_2 = 102;
  92         const DETECT_NODEINFO_210 = 103;
  93
  94         /**
  95          * Check for the existance of a server and adds it in the background if not existant
  96          *
  97          * @param string $url
  98          * @param boolean $only_nodeinfo
  99          *
 100          * @return void
 101          */
 102         public static function add(string $url, bool $only_nodeinfo = false)
 103         {
 104                 if (self::getID($url)) {
 105                         return;
 106                 }
 107
 108                 UpdateGServer::add(Worker::PRIORITY_LOW, $url, $only_nodeinfo);
 109         }
 110
 111         /**
 112          * Get the ID for the given server URL
 113          *
 114          * @param string $url
 115          * @param boolean $no_check Don't check if the server hadn't been found
 116          *
 117          * @return int|null gserver id or NULL on empty URL or failed check
 118          */
 119         public static function getID(string $url, bool $no_check = false): ?int
 120         {
 121                 $url = self::cleanURL($url);
 122
 123                 if (empty($url)) {
 124                         return null;
 125                 }
 126
 127                 $gserver = DBA::selectFirst('gserver', ['id'], ['nurl' => Strings::normaliseLink($url)]);
 128                 if (DBA::isResult($gserver)) {
 129                         Logger::debug('Got ID for URL', ['id' => $gserver['id'], 'url' => $url, 'callstack' => System::callstack(20)]);
 130
 131                         if (Network::isUrlBlocked($url)) {
 132                                 self::setBlockedById($gserver['id']);
 133                         } else {
 134                                 self::setUnblockedById($gserver['id']);
 135                         }
 136
 137                         return $gserver['id'];
 138                 }
 139
 140                 if ($no_check || !self::check($url)) {
 141                         return null;
 142                 }
 143
 144                 return self::getID($url, true);
 145         }
 146
 147         /**
 148          * Retrieves all the servers which base domain are matching the provided domain pattern
 149          *
 150          * The pattern is a simple fnmatch() pattern with ? for single wildcard and * for multiple wildcard
 151          *
 152          * @param string $pattern
 153          *
 154          * @return array
 155          *
 156          * @throws Exception
 157          */
 158         public static function listByDomainPattern(string $pattern): array
 159         {
 160                 $likePattern = 'http://' . strtr($pattern, ['_' => '\_', '%' => '\%', '?' => '_', '*' => '%']);
 161
 162                 // The SUBSTRING_INDEX returns everything before the eventual third /, which effectively trims an
 163                 // eventual server path and keep only the server domain which we're matching against the pattern.
 164                 $sql = "SELECT `gserver`.*, COUNT(*) AS `contacts`
 165                         FROM `gserver`
 166                         LEFT JOIN `contact` ON `gserver`.`id` = `contact`.`gsid`
 167                         WHERE SUBSTRING_INDEX(`gserver`.`nurl`, '/', 3) LIKE ?
 168                         AND NOT `gserver`.`failed`
 169                         GROUP BY `gserver`.`id`";
 170
 171                 $stmt = DI::dba()->p($sql, $likePattern);
 172
 173                 return DI::dba()->toArray($stmt);
 174         }
 175
 176         /**
 177          * Checks if the given server array is unreachable for a long time now
 178          *
 179          * @param integer $gsid
 180          * @return boolean
 181          */
 182         private static function isDefunct(array $gserver): bool
 183         {
 184                 return ($gserver['failed'] || in_array($gserver['network'], Protocol::FEDERATED)) &&
 185                         ($gserver['last_contact'] >= $gserver['created']) &&
 186                         ($gserver['last_contact'] < $gserver['last_failure']) &&
 187                         ($gserver['last_contact'] < DateTimeFormat::utc('now - 90 days'));
 188         }
 189
 190         /**
 191          * Checks if the given server id is unreachable for a long time now
 192          *
 193          * @param integer $gsid
 194          * @return boolean
 195          */
 196         public static function isDefunctById(int $gsid): bool
 197         {
 198                 $gserver = DBA::selectFirst('gserver', ['url', 'next_contact', 'last_contact', 'last_failure', 'created', 'failed', 'network'], ['id' => $gsid]);
 199                 if (empty($gserver)) {
 200                         return false;
 201                 } else {
 202                         if (strtotime($gserver['next_contact']) < time()) {
 203                                 UpdateGServer::add(Worker::PRIORITY_LOW, $gserver['url']);
 204                         }
 205
 206                         return self::isDefunct($gserver);
 207                 }
 208         }
 209
 210         /**
 211          * Checks if the given server id is reachable
 212          *
 213          * @param integer $gsid
 214          * @return boolean
 215          */
 216         public static function isReachableById(int $gsid): bool
 217         {
 218                 $gserver = DBA::selectFirst('gserver', ['url', 'next_contact', 'failed', 'network'], ['id' => $gsid]);
 219                 if (empty($gserver)) {
 220                         return true;
 221                 } else {
 222                         if (strtotime($gserver['next_contact']) < time()) {
 223                                 UpdateGServer::add(Worker::PRIORITY_LOW, $gserver['url']);
 224                         }
 225
 226                         return !$gserver['failed'] && in_array($gserver['network'], Protocol::FEDERATED);
 227                 }
 228         }
 229
 230         /**
 231          * Checks if the given server is reachable
 232          *
 233          * @param array $contact Contact that should be checked
 234          *
 235          * @return boolean 'true' if server seems vital
 236          */
 237         public static function reachable(array $contact): bool
 238         {
 239                 if (!empty($contact['gsid'])) {
 240                         $gsid = $contact['gsid'];
 241                 } elseif (!empty($contact['baseurl'])) {
 242                         $server = $contact['baseurl'];
 243                 } elseif ($contact['network'] == Protocol::DIASPORA) {
 244                         $parts = parse_url($contact['url']);
 245                         unset($parts['path']);
 246                         $server = (string)Uri::fromParts($parts);
 247                 } else {
 248                         return true;
 249                 }
 250
 251                 if (!empty($gsid)) {
 252                         $condition = ['id' => $gsid];
 253                 } else {
 254                         $condition = ['nurl' => Strings::normaliseLink($server)];
 255                 }
 256
 257                 $gserver = DBA::selectFirst('gserver', ['url', 'next_contact', 'failed', 'network'], $condition);
 258                 if (empty($gserver)) {
 259                         $reachable = true;
 260                 } else {
 261                         $reachable = !$gserver['failed'] && in_array($gserver['network'], Protocol::FEDERATED);
 262                         $server    = $gserver['url'];
 263                 }
 264
 265                 if (!empty($server) && (empty($gserver) || strtotime($gserver['next_contact']) < time())) {
 266                         UpdateGServer::add(Worker::PRIORITY_LOW, $server);
 267                 }
 268
 269                 return $reachable;
 270         }
 271
 272         /**
 273          * Calculate the next update day
 274          *
 275          * @param bool $success
 276          * @param string $created
 277          * @param string $last_contact
 278          * @param bool $undetected
 279          *
 280          * @return string
 281          *
 282          * @throws Exception
 283          */
 284         public static function getNextUpdateDate(bool $success, string $created = '', string $last_contact = '', bool $undetected = false): string
 285         {
 286                 // On successful contact process check again next week when it is a detected system.
 287                 // When we haven't detected the system, it could be a static website or a really old system.
 288                 if ($success) {
 289                         return DateTimeFormat::utc($undetected ? 'now +1 month' : 'now +7 day');
 290                 }
 291
 292                 $now = strtotime(DateTimeFormat::utcNow());
 293
 294                 if ($created > $last_contact) {
 295                         $contact_time = strtotime($created);
 296                 } else {
 297                         $contact_time = strtotime($last_contact);
 298                 }
 299
 300                 // If the last contact was less than 6 hours before then try again in 6 hours
 301                 if (($now - $contact_time) < (60 * 60 * 6)) {
 302                         return DateTimeFormat::utc('now +6 hour');
 303                 }
 304
 305                 // If the last contact was less than 12 hours before then try again in 12 hours
 306                 if (($now - $contact_time) < (60 * 60 * 12)) {
 307                         return DateTimeFormat::utc('now +12 hour');
 308                 }
 309
 310                 // If the last contact was less than 24 hours before then try tomorrow again
 311                 if (($now - $contact_time) < (60 * 60 * 24)) {
 312                         return DateTimeFormat::utc('now +1 day');
 313                 }
 314
 315                 // If the last contact was less than a week before then try again in a week
 316                 if (($now - $contact_time) < (60 * 60 * 24 * 7)) {
 317                         return DateTimeFormat::utc('now +1 week');
 318                 }
 319
 320                 // If the last contact was less than two weeks before then try again in two week
 321                 if (($now - $contact_time) < (60 * 60 * 24 * 14)) {
 322                         return DateTimeFormat::utc('now +2 week');
 323                 }
 324
 325                 // If the last contact was less than a month before then try again in a month
 326                 if (($now - $contact_time) < (60 * 60 * 24 * 30)) {
 327                         return DateTimeFormat::utc('now +1 month');
 328                 }
 329
 330                 // The system hadn't been successul contacted for more than a month, so try again in three months
 331                 return DateTimeFormat::utc('now +3 month');
 332         }
 333
 334         /**
 335          * Checks the state of the given server.
 336          *
 337          * @param string  $server_url    URL of the given server
 338          * @param string  $network       Network value that is used, when detection failed
 339          * @param boolean $force         Force an update.
 340          * @param boolean $only_nodeinfo Only use nodeinfo for server detection
 341          *
 342          * @return boolean 'true' if server seems vital
 343          */
 344         public static function check(string $server_url, string $network = '', bool $force = false, bool $only_nodeinfo = false): bool
 345         {
 346                 $server_url = self::cleanURL($server_url);
 347                 if ($server_url == '') {
 348                         return false;
 349                 }
 350
 351                 if (Network::isUrlBlocked($server_url)) {
 352                         Logger::info('Server is blocked', ['url' => $server_url]);
 353                         self::setBlockedByUrl($server_url);
 354                         return false;
 355                 }
 356
 357                 $gserver = DBA::selectFirst('gserver', [], ['nurl' => Strings::normaliseLink($server_url)]);
 358                 if (DBA::isResult($gserver)) {
 359                         if ($gserver['created'] <= DBA::NULL_DATETIME) {
 360                                 $fields = ['created' => DateTimeFormat::utcNow()];
 361                                 $condition = ['nurl' => Strings::normaliseLink($server_url)];
 362                                 self::update($fields, $condition);
 363                         }
 364
 365                         if (!$force && (strtotime($gserver['next_contact']) > time())) {
 366                                 Logger::info('No update needed', ['server' => $server_url]);
 367                                 return (!$gserver['failed']);
 368                         }
 369                         Logger::info('Server is outdated. Start discovery.', ['Server' => $server_url, 'Force' => $force]);
 370                 } else {
 371                         Logger::info('Server is unknown. Start discovery.', ['Server' => $server_url]);
 372                 }
 373
 374                 return self::detect($server_url, $network, $only_nodeinfo);
 375         }
 376
 377         /**
 378          * Reset failed server status by gserver id
 379          *
 380          * @param int    $gsid
 381          * @param string $network
 382          */
 383         public static function setReachableById(int $gsid, string $network)
 384         {
 385                 $gserver = DBA::selectFirst('gserver', ['url', 'failed', 'next_contact', 'network'], ['id' => $gsid]);
 386                 if (!DBA::isResult($gserver)) {
 387                         return;
 388                 }
 389
 390                 $blocked = Network::isUrlBlocked($gserver['url']);
 391                 if ($gserver['failed']) {
 392                         $fields = ['failed' => false, 'blocked' => $blocked, 'last_contact' => DateTimeFormat::utcNow()];
 393                         if (!empty($network) && !in_array($gserver['network'], Protocol::FEDERATED)) {
 394                                 $fields['network'] = $network;
 395                         }
 396                         self::update($fields, ['id' => $gsid]);
 397                         Logger::info('Reset failed status for server', ['url' => $gserver['url']]);
 398
 399                         if (strtotime($gserver['next_contact']) < time()) {
 400                                 UpdateGServer::add(Worker::PRIORITY_LOW, $gserver['url']);
 401                         }
 402                 } elseif ($blocked) {
 403                         self::setBlockedById($gsid);
 404                 } else {
 405                         self::setUnblockedById($gsid);
 406                 }
 407         }
 408
 409         /**
 410          * Set failed server status by gserver id
 411          *
 412          * @param int $gsid
 413          */
 414         public static function setFailureById(int $gsid)
 415         {
 416                 $gserver = DBA::selectFirst('gserver', ['url', 'failed', 'next_contact'], ['id' => $gsid]);
 417                 if (DBA::isResult($gserver) && !$gserver['failed']) {
 418                         self::update(['failed' => true, 'blocked' => Network::isUrlBlocked($gserver['url']), 'last_failure' => DateTimeFormat::utcNow()], ['id' => $gsid]);
 419                         Logger::info('Set failed status for server', ['url' => $gserver['url']]);
 420
 421                         if (strtotime($gserver['next_contact']) < time()) {
 422                                 UpdateGServer::add(Worker::PRIORITY_LOW, $gserver['url']);
 423                         }
 424                 }
 425         }
 426
 427         public static function setUnblockedById(int $gsid)
 428         {
 429                 $gserver = DBA::selectFirst('gserver', ['url'], ["(`blocked` OR `blocked` IS NULL) AND `id` = ?", $gsid]);
 430                 if (DBA::isResult($gserver)) {
 431                         self::update(['blocked' => false], ['id' => $gsid]);
 432                         Logger::info('Set unblocked status for server', ['url' => $gserver['url']]);
 433                 }
 434         }
 435
 436         public static function setBlockedById(int $gsid)
 437         {
 438                 $gserver = DBA::selectFirst('gserver', ['url'], ["(NOT `blocked` OR `blocked` IS NULL) AND `id` = ?", $gsid]);
 439                 if (DBA::isResult($gserver)) {
 440                         self::update(['blocked' => true, 'failed' => true], ['id' => $gsid]);
 441                         Logger::info('Set blocked status for server', ['url' => $gserver['url']]);
 442                 }
 443         }
 444
 445         public static function setBlockedByUrl(string $url)
 446         {
 447                 $gserver = DBA::selectFirst('gserver', ['url', 'id'], ["(NOT `blocked` OR `blocked` IS NULL) AND `nurl` = ?", Strings::normaliseLink($url)]);
 448                 if (DBA::isResult($gserver)) {
 449                         self::update(['blocked' => true, 'failed' => true], ['id' => $gserver['id']]);
 450                         Logger::info('Set blocked status for server', ['url' => $gserver['url']]);
 451                 }
 452         }
 453
 454         /**
 455          * Set failed server status
 456          *
 457          * @param string $url
 458          * @return void
 459          */
 460         public static function setFailureByUrl(string $url)
 461         {
 462                 $nurl = Strings::normaliseLink($url);
 463
 464                 $gserver = DBA::selectFirst('gserver', [], ['nurl' => $nurl]);
 465                 if (DBA::isResult($gserver)) {
 466                         $next_update = self::getNextUpdateDate(false, $gserver['created'], $gserver['last_contact']);
 467                         self::update(['url' => $url, 'failed' => true, 'blocked' => Network::isUrlBlocked($url), 'last_failure' => DateTimeFormat::utcNow(),
 468                         'next_contact' => $next_update, 'network' => Protocol::PHANTOM, 'detection-method' => null],
 469                         ['nurl' => $nurl]);
 470                         Logger::info('Set failed status for existing server', ['url' => $url]);
 471                         if (self::isDefunct($gserver)) {
 472                                 self::archiveContacts($gserver['id']);
 473                         }
 474                         return;
 475                 }
 476
 477                 self::insert(['url' => $url, 'nurl' => $nurl,
 478                         'network' => Protocol::PHANTOM, 'created' => DateTimeFormat::utcNow(),
 479                         'failed' => true, 'last_failure' => DateTimeFormat::utcNow()]);
 480                 Logger::info('Set failed status for new server', ['url' => $url]);
 481         }
 482
 483         /**
 484          * Archive server related contacts and inboxes
 485          *
 486          * @param integer $gsid
 487          * @return void
 488          */
 489         private static function archiveContacts(int $gsid)
 490         {
 491                 Contact::update(['archive' => true], ['gsid' => $gsid]);
 492                 DBA::update('inbox-status', ['archive' => true], ['gsid' => $gsid]);
 493         }
 494
 495         /**
 496          * Remove unwanted content from the given URL
 497          *
 498          * @param string $dirtyUrl
 499          *
 500          * @return string cleaned URL
 501          * @throws Exception
 502          * @deprecated since 2023.03 Use cleanUri instead
 503          */
 504         public static function cleanURL(string $dirtyUrl): string
 505         {
 506                 try {
 507                         return (string)self::cleanUri(new Uri($dirtyUrl));
 508                 } catch (\Throwable $e) {
 509                         Logger::warning('Invalid URL', ['dirtyUrl' => $dirtyUrl]);
 510                         return '';
 511                 }
 512         }
 513
 514         /**
 515          * Remove unwanted content from the given URI
 516          *
 517          * @param UriInterface $dirtyUri
 518          *
 519          * @return UriInterface cleaned URI
 520          * @throws Exception
 521          */
 522         public static function cleanUri(UriInterface $dirtyUri): string
 523         {
 524                 return $dirtyUri
 525                         ->withUserInfo('')
 526                         ->withQuery('')
 527                         ->withFragment('')
 528                         ->withPath(
 529                                 preg_replace(
 530                                         '#(?:^|/)index\.php#',
 531                                         '',
 532                                         rtrim($dirtyUri->getPath(), '/')
 533                                 )
 534                         );
 535         }
 536
 537         /**
 538          * Detect server data (type, protocol, version number, ...)
 539          * The detected data is then updated or inserted in the gserver table.
 540          *
 541          * @param string  $url           URL of the given server
 542          * @param string  $network       Network value that is used, when detection failed
 543          * @param boolean $only_nodeinfo Only use nodeinfo for server detection
 544          *
 545          * @return boolean 'true' if server could be detected
 546          */
 547         private static function detect(string $url, string $network = '', bool $only_nodeinfo = false): bool
 548         {
 549                 Logger::info('Detect server type', ['server' => $url]);
 550
 551                 $original_url = $url;
 552
 553                 // Remove URL content that is not supposed to exist for a server url
 554                 $url = rtrim(self::cleanURL($url), '/');
 555                 if (empty($url)) {
 556                         Logger::notice('Empty URL.');
 557                         return false;
 558                 }
 559
 560                 // If the URL missmatches, then we mark the old entry as failure
 561                 if (!Strings::compareLink($url, $original_url)) {
 562                         self::setFailureByUrl($original_url);
 563                         if (!self::getID($url, true) && !Network::isUrlBlocked($url)) {
 564                                 self::detect($url, $network, $only_nodeinfo);
 565                         }
 566                         return false;
 567                 }
 568
 569                 $valid_url = Network::isUrlValid($url);
 570                 if (!$valid_url) {
 571                         self::setFailureByUrl($url);
 572                         return false;
 573                 } else {
 574                         $valid_url = rtrim($valid_url, '/');
 575                 }
 576
 577                 if (!Strings::compareLink($url, $valid_url)) {
 578                         // We only follow redirects when the path stays the same or the target url has no path.
 579                         // Some systems have got redirects on their landing page to a single account page. This check handles it.
 580                         if (((parse_url($url, PHP_URL_HOST) != parse_url($valid_url, PHP_URL_HOST)) && (parse_url($url, PHP_URL_PATH) == parse_url($valid_url, PHP_URL_PATH))) ||
 581                                 (((parse_url($url, PHP_URL_HOST) != parse_url($valid_url, PHP_URL_HOST)) || (parse_url($url, PHP_URL_PATH) != parse_url($valid_url, PHP_URL_PATH))) && empty(parse_url($valid_url, PHP_URL_PATH)))) {
 582                                 Logger::debug('Found redirect. Mark old entry as failure', ['old' => $url, 'new' => $valid_url]);
 583                                 self::setFailureByUrl($url);
 584                                 if (!self::getID($valid_url, true) && !Network::isUrlBlocked($valid_url)) {
 585                                         self::detect($valid_url, $network, $only_nodeinfo);
 586                                 }
 587                                 return false;
 588                         }
 589
 590                         if ((parse_url($url, PHP_URL_HOST) != parse_url($valid_url, PHP_URL_HOST)) && (parse_url($url, PHP_URL_PATH) != parse_url($valid_url, PHP_URL_PATH)) &&
 591                                 (parse_url($url, PHP_URL_PATH) == '')) {
 592                                 Logger::debug('Found redirect. Mark old entry as failure and redirect to the basepath.', ['old' => $url, 'new' => $valid_url]);
 593                                 $parts = parse_url($valid_url);
 594                                 unset($parts['path']);
 595                                 $valid_url = (string)Uri::fromParts($parts);
 596
 597                                 self::setFailureByUrl($url);
 598                                 if (!self::getID($valid_url, true) && !Network::isUrlBlocked($valid_url)) {
 599                                         self::detect($valid_url, $network, $only_nodeinfo);
 600                                 }
 601                                 return false;
 602                         }
 603                         Logger::debug('Found redirect, but ignore it.', ['old' => $url, 'new' => $valid_url]);
 604                 }
 605
 606                 if ((parse_url($url, PHP_URL_HOST) == parse_url($valid_url, PHP_URL_HOST)) &&
 607                         (parse_url($url, PHP_URL_PATH) == parse_url($valid_url, PHP_URL_PATH)) &&
 608                         (parse_url($url, PHP_URL_SCHEME) != parse_url($valid_url, PHP_URL_SCHEME))) {
 609                         $url = $valid_url;
 610                 }
 611
 612                 $in_webroot = empty(parse_url($url, PHP_URL_PATH));
 613
 614                 // When a nodeinfo is present, we don't need to dig further
 615                 $curlResult = DI::httpClient()->get($url . '/.well-known/x-nodeinfo2', HttpClientAccept::JSON);
 616                 if ($curlResult->isTimeout()) {
 617                         self::setFailureByUrl($url);
 618                         return false;
 619                 }
 620
 621                 $serverdata = self::parseNodeinfo210($curlResult);
 622                 if (empty($serverdata)) {
 623                         $curlResult = DI::httpClient()->get($url . '/.well-known/nodeinfo', HttpClientAccept::JSON);
 624                         $serverdata = self::fetchNodeinfo($url, $curlResult);
 625                 }
 626
 627                 if ($only_nodeinfo && empty($serverdata)) {
 628                         Logger::info('Invalid nodeinfo in nodeinfo-mode, server is marked as failure', ['url' => $url]);
 629                         self::setFailureByUrl($url);
 630                         return false;
 631                 } elseif (empty($serverdata)) {
 632                         $serverdata = ['detection-method' => self::DETECT_MANUAL, 'network' => Protocol::PHANTOM, 'platform' => '', 'version' => '', 'site_name' => '', 'info' => ''];
 633                 }
 634
 635                 // When there is no Nodeinfo, then use some protocol specific endpoints
 636                 if ($serverdata['network'] == Protocol::PHANTOM) {
 637                         if ($in_webroot) {
 638                                 // Fetch the landing page, possibly it reveals some data
 639                                 $accept = 'application/activity+json,application/ld+json,application/json,*/*;q=0.9';
 640                                 $curlResult = DI::httpClient()->get($url, $accept);
 641                                 if (!$curlResult->isSuccess() && $curlResult->getReturnCode() == '406') {
 642                                         $curlResult = DI::httpClient()->get($url, HttpClientAccept::HTML);
 643                                         $html_fetched = true;
 644                                 } else {
 645                                         $html_fetched = false;
 646                                 }
 647
 648                                 if ($curlResult->isSuccess()) {
 649                                         $json = json_decode($curlResult->getBody(), true);
 650                                         if (!empty($json) && is_array($json)) {
 651                                                 $data = self::fetchDataFromSystemActor($json, $serverdata);
 652                                                 $serverdata = $data['server'];
 653                                                 $systemactor = $data['actor'];
 654                                                 if (!$html_fetched && !in_array($serverdata['detection-method'], [self::DETECT_SYSTEM_ACTOR, self::DETECT_AP_COLLECTION])) {
 655                                                         $curlResult = DI::httpClient()->get($url, HttpClientAccept::HTML);
 656                                                 }
 657                                         } elseif (!$html_fetched && (strlen($curlResult->getBody()) < 1000)) {
 658                                                 $curlResult = DI::httpClient()->get($url, HttpClientAccept::HTML);
 659                                         }
 660
 661                                         if ($serverdata['detection-method'] != self::DETECT_SYSTEM_ACTOR) {
 662                                                 $serverdata = self::analyseRootHeader($curlResult, $serverdata);
 663                                                 $serverdata = self::analyseRootBody($curlResult, $serverdata);
 664                                         }
 665                                 }
 666
 667                                 if (!$curlResult->isSuccess() || empty($curlResult->getBody())) {
 668                                         self::setFailureByUrl($url);
 669                                         return false;
 670                                 }
 671
 672                                 if (($serverdata['network'] == Protocol::PHANTOM) || in_array($serverdata['detection-method'], self::DETECT_UNSPECIFIC)) {
 673                                         $serverdata = self::detectMastodonAlikes($url, $serverdata);
 674                                 }
 675                         }
 676
 677                         // All following checks are done for systems that always have got a "host-meta" endpoint.
 678                         // With this check we don't have to waste time and ressources for dead systems.
 679                         // Also this hopefully prevents us from receiving abuse messages.
 680                         if (($serverdata['network'] == Protocol::PHANTOM) || in_array($serverdata['detection-method'], self::DETECT_UNSPECIFIC)) {
 681                                 $validHostMeta = self::validHostMeta($url);
 682                         } else {
 683                                 $validHostMeta = false;
 684                         }
 685
 686                         if ($validHostMeta) {
 687                                 if (in_array($serverdata['detection-method'], [self::DETECT_MANUAL, self::DETECT_HEADER, self::DETECT_BODY])) {
 688                                         $serverdata['detection-method'] = self::DETECT_HOST_META;
 689                                 }
 690
 691                                 if (($serverdata['network'] == Protocol::PHANTOM) || in_array($serverdata['detection-method'], self::DETECT_UNSPECIFIC)) {
 692                                         $serverdata = self::detectFriendica($url, $serverdata);
 693                                 }
 694
 695                                 // The following systems have to be installed in the root directory.
 696                                 if ($in_webroot) {
 697                                         // the 'siteinfo.json' is some specific endpoint of Hubzilla and Red
 698                                         if (($serverdata['network'] == Protocol::PHANTOM) || in_array($serverdata['detection-method'], self::DETECT_UNSPECIFIC)) {
 699                                                 $serverdata = self::fetchSiteinfo($url, $serverdata);
 700                                         }
 701
 702                                         // The 'siteinfo.json' doesn't seem to be present on older Hubzilla installations, so we check other endpoints as well
 703                                         if (($serverdata['network'] == Protocol::PHANTOM) || in_array($serverdata['detection-method'], self::DETECT_UNSPECIFIC)) {
 704                                                 $serverdata = self::detectHubzilla($url, $serverdata);
 705                                         }
 706
 707                                         if (($serverdata['network'] == Protocol::PHANTOM) || in_array($serverdata['detection-method'], self::DETECT_UNSPECIFIC)) {
 708                                                 $serverdata = self::detectPeertube($url, $serverdata);
 709                                         }
 710
 711                                         if (($serverdata['network'] == Protocol::PHANTOM) || in_array($serverdata['detection-method'], self::DETECT_UNSPECIFIC)) {
 712                                                 $serverdata = self::detectGNUSocial($url, $serverdata);
 713                                         }
 714                                 }
 715                         } elseif (in_array($serverdata['platform'], ['friendica', 'friendika']) && in_array($serverdata['detection-method'], array_merge(self::DETECT_UNSPECIFIC, [self::DETECT_SYSTEM_ACTOR]))) {
 716                                 $serverdata = self::detectFriendica($url, $serverdata);
 717                         }
 718
 719                         if (($serverdata['network'] == Protocol::PHANTOM) || in_array($serverdata['detection-method'], self::DETECT_UNSPECIFIC)) {
 720                                 $serverdata = self::detectNextcloud($url, $serverdata, $validHostMeta);
 721                         }
 722
 723                         // When nodeinfo isn't present, we use the older 'statistics.json' endpoint
 724                         // Since this endpoint is only rarely used, we query it at a later time
 725                         if (in_array($serverdata['detection-method'], array_merge(self::DETECT_UNSPECIFIC, [self::DETECT_FRIENDICA, self::DETECT_CONFIG_JSON]))) {
 726                                 $serverdata = self::fetchStatistics($url, $serverdata);
 727                         }
 728                 }
 729
 730                 // When we hadn't been able to detect the network type, we use the hint from the parameter
 731                 if (($serverdata['network'] == Protocol::PHANTOM) && !empty($network)) {
 732                         $serverdata['network'] = $network;
 733                 }
 734
 735                 // Most servers aren't installed in a subdirectory, so we declare this entry as failed
 736                 if (($serverdata['network'] == Protocol::PHANTOM) && !empty(parse_url($url, PHP_URL_PATH)) && in_array($serverdata['detection-method'], [self::DETECT_MANUAL])) {
 737                         self::setFailureByUrl($url);
 738                         return false;
 739                 }
 740
 741                 $serverdata['url'] = $url;
 742                 $serverdata['nurl'] = Strings::normaliseLink($url);
 743
 744                 // We have to prevent an endless loop here.
 745                 // When a server is new, then there is no gserver entry yet.
 746                 // But in "detectNetworkViaContacts" it could happen that a contact is updated,
 747                 // and this can call this function here as well.
 748                 if (self::getID($url, true) && (in_array($serverdata['network'], [Protocol::PHANTOM, Protocol::FEED]) ||
 749                         in_array($serverdata['detection-method'], [self::DETECT_MANUAL, self::DETECT_HEADER, self::DETECT_BODY, self::DETECT_HOST_META]))) {
 750                         $serverdata = self::detectNetworkViaContacts($url, $serverdata);
 751                 }
 752
 753                 if (($serverdata['network'] == Protocol::PHANTOM) && in_array($serverdata['detection-method'], [self::DETECT_MANUAL, self::DETECT_BODY])) {
 754                         self::setFailureByUrl($url);
 755                         return false;
 756                 }
 757
 758                 // Detect the directory type
 759                 $serverdata['directory-type'] = self::DT_NONE;
 760
 761                 if (in_array($serverdata['network'], Protocol::FEDERATED)) {
 762                         $serverdata = self::checkMastodonDirectory($url, $serverdata);
 763
 764                         if ($serverdata['directory-type'] == self::DT_NONE) {
 765                                 $serverdata = self::checkPoCo($url, $serverdata);
 766                         }
 767                 }
 768
 769                 if ($serverdata['network'] == Protocol::ACTIVITYPUB) {
 770                         $serverdata = self::fetchWeeklyUsage($url, $serverdata);
 771                 }
 772
 773                 $serverdata['registered-users'] = $serverdata['registered-users'] ?? 0;
 774
 775                 // Numbers above a reasonable value (10 millions) are ignored
 776                 if ($serverdata['registered-users'] > 10000000) {
 777                         $serverdata['registered-users'] = 0;
 778                 }
 779
 780                 // On an active server there has to be at least a single user
 781                 if (!in_array($serverdata['network'], [Protocol::PHANTOM, Protocol::FEED]) && ($serverdata['registered-users'] <= 0)) {
 782                         $serverdata['registered-users'] = 1;
 783                 } elseif (in_array($serverdata['network'], [Protocol::PHANTOM, Protocol::FEED])) {
 784                         $serverdata['registered-users'] = 0;
 785                 }
 786
 787                 $serverdata['next_contact'] = self::getNextUpdateDate(true, '', '', in_array($serverdata['network'], [Protocol::PHANTOM, Protocol::FEED]));
 788                 $serverdata['last_contact'] = DateTimeFormat::utcNow();
 789                 $serverdata['failed']       = false;
 790                 $serverdata['blocked']      = false;
 791
 792                 $gserver = DBA::selectFirst('gserver', ['network'], ['nurl' => Strings::normaliseLink($url)]);
 793                 if (!DBA::isResult($gserver)) {
 794                         $serverdata['created'] = DateTimeFormat::utcNow();
 795                         $ret = self::insert($serverdata);
 796                         $id = DBA::lastInsertId();
 797                 } else {
 798                         $ret = self::update($serverdata, ['nurl' => $serverdata['nurl']]);
 799                         $gserver = DBA::selectFirst('gserver', ['id'], ['nurl' => $serverdata['nurl']]);
 800                         if (DBA::isResult($gserver)) {
 801                                 $id = $gserver['id'];
 802                         }
 803                 }
 804
 805                 // Count the number of known contacts from this server
 806                 if (!empty($id) && !in_array($serverdata['network'], [Protocol::PHANTOM, Protocol::FEED])) {
 807                         $apcontacts = DBA::count('apcontact', ['gsid' => $id]);
 808                         $contacts = DBA::count('contact', ['uid' => 0, 'gsid' => $id, 'failed' => false]);
 809                         $max_users = max($apcontacts, $contacts);
 810                         if ($max_users > $serverdata['registered-users']) {
 811                                 Logger::info('Update registered users', ['id' => $id, 'url' => $serverdata['nurl'], 'registered-users' => $max_users]);
 812                                 self::update(['registered-users' => $max_users], ['id' => $id]);
 813                         }
 814
 815                         if (empty($serverdata['active-month-users'])) {
 816                                 $contacts = DBA::count('contact', ["`uid` = ? AND `gsid` = ? AND NOT `failed` AND `last-item` > ?", 0, $id, DateTimeFormat::utc('now - 30 days')]);
 817                                 if ($contacts > 0) {
 818                                         Logger::info('Update monthly users', ['id' => $id, 'url' => $serverdata['nurl'], 'monthly-users' => $contacts]);
 819                                         self::update(['active-month-users' => $contacts], ['id' => $id]);
 820                                 }
 821                         }
 822
 823                         if (empty($serverdata['active-halfyear-users'])) {
 824                                 $contacts = DBA::count('contact', ["`uid` = ? AND `gsid` = ? AND NOT `failed` AND `last-item` > ?", 0, $id, DateTimeFormat::utc('now - 180 days')]);
 825                                 if ($contacts > 0) {
 826                                         Logger::info('Update halfyear users', ['id' => $id, 'url' => $serverdata['nurl'], 'halfyear-users' => $contacts]);
 827                                         self::update(['active-halfyear-users' => $contacts], ['id' => $id]);
 828                                 }
 829                         }
 830                 }
 831
 832                 if (in_array($serverdata['network'], [Protocol::DFRN, Protocol::DIASPORA])) {
 833                         self::discoverRelay($url);
 834                 }
 835
 836                 if (!empty($systemactor)) {
 837                         $contact = Contact::getByURL($systemactor, true, ['gsid', 'baseurl', 'id', 'network', 'url', 'name']);
 838                         Logger::debug('Fetched system actor',  ['url' => $url, 'gsid' => $id, 'contact' => $contact]);
 839                 }
 840
 841                 return $ret;
 842         }
 843
 844         /**
 845          * Fetch relay data from a given server url
 846          *
 847          * @param string $server_url address of the server
 848          *
 849          * @return void
 850          *
 851          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 852          */
 853         private static function discoverRelay(string $server_url)
 854         {
 855                 Logger::info('Discover relay data', ['server' => $server_url]);
 856
 857                 $curlResult = DI::httpClient()->get($server_url . '/.well-known/x-social-relay', HttpClientAccept::JSON);
 858                 if (!$curlResult->isSuccess()) {
 859                         return;
 860                 }
 861
 862                 $data = json_decode($curlResult->getBody(), true);
 863                 if (!is_array($data)) {
 864                         return;
 865                 }
 866
 867                 // Sanitize incoming data, see https://github.com/friendica/friendica/issues/8565
 868                 $data['subscribe'] = (bool)$data['subscribe'] ?? false;
 869
 870                 if (!$data['subscribe'] || empty($data['scope']) || !in_array(strtolower($data['scope']), ['all', 'tags'])) {
 871                         $data['scope'] = '';
 872                         $data['subscribe'] = false;
 873                         $data['tags'] = [];
 874                 }
 875
 876                 $gserver = DBA::selectFirst('gserver', ['id', 'url', 'network', 'relay-subscribe', 'relay-scope'], ['nurl' => Strings::normaliseLink($server_url)]);
 877                 if (!DBA::isResult($gserver)) {
 878                         return;
 879                 }
 880
 881                 if (($gserver['relay-subscribe'] != $data['subscribe']) || ($gserver['relay-scope'] != $data['scope'])) {
 882                         $fields = ['relay-subscribe' => $data['subscribe'], 'relay-scope' => $data['scope']];
 883                         self::update($fields, ['id' => $gserver['id']]);
 884                 }
 885
 886                 DBA::delete('gserver-tag', ['gserver-id' => $gserver['id']]);
 887
 888                 if ($data['scope'] == 'tags') {
 889                         // Avoid duplicates
 890                         $tags = [];
 891                         foreach ($data['tags'] as $tag) {
 892                                 $tag = mb_strtolower($tag);
 893                                 if (strlen($tag) < 100) {
 894                                         $tags[$tag] = $tag;
 895                                 }
 896                         }
 897
 898                         foreach ($tags as $tag) {
 899                                 DBA::insert('gserver-tag', ['gserver-id' => $gserver['id'], 'tag' => $tag], Database::INSERT_IGNORE);
 900                         }
 901                 }
 902
 903                 // Create or update the relay contact
 904                 $fields = [];
 905                 if (isset($data['protocols'])) {
 906                         if (isset($data['protocols']['diaspora'])) {
 907                                 $fields['network'] = Protocol::DIASPORA;
 908
 909                                 if (isset($data['protocols']['diaspora']['receive'])) {
 910                                         $fields['batch'] = $data['protocols']['diaspora']['receive'];
 911                                 } elseif (is_string($data['protocols']['diaspora'])) {
 912                                         $fields['batch'] = $data['protocols']['diaspora'];
 913                                 }
 914                         }
 915
 916                         if (isset($data['protocols']['dfrn'])) {
 917                                 $fields['network'] = Protocol::DFRN;
 918
 919                                 if (isset($data['protocols']['dfrn']['receive'])) {
 920                                         $fields['batch'] = $data['protocols']['dfrn']['receive'];
 921                                 } elseif (is_string($data['protocols']['dfrn'])) {
 922                                         $fields['batch'] = $data['protocols']['dfrn'];
 923                                 }
 924                         }
 925
 926                         if (isset($data['protocols']['activitypub'])) {
 927                                 $fields['network'] = Protocol::ACTIVITYPUB;
 928
 929                                 if (!empty($data['protocols']['activitypub']['actor'])) {
 930                                         $fields['url'] = $data['protocols']['activitypub']['actor'];
 931                                 }
 932                                 if (!empty($data['protocols']['activitypub']['receive'])) {
 933                                         $fields['batch'] = $data['protocols']['activitypub']['receive'];
 934                                 }
 935                         }
 936                 }
 937
 938                 Logger::info('Discovery ended', ['server' => $server_url, 'data' => $fields]);
 939
 940                 Relay::updateContact($gserver, $fields);
 941         }
 942
 943         /**
 944          * Fetch server data from '/statistics.json' on the given server
 945          *
 946          * @param string $url URL of the given server
 947          *
 948          * @return array server data
 949          */
 950         private static function fetchStatistics(string $url, array $serverdata): array
 951         {
 952                 $curlResult = DI::httpClient()->get($url . '/statistics.json', HttpClientAccept::JSON);
 953                 if (!$curlResult->isSuccess()) {
 954                         return $serverdata;
 955                 }
 956
 957                 $data = json_decode($curlResult->getBody(), true);
 958                 if (empty($data)) {
 959                         return $serverdata;
 960                 }
 961
 962                 // Some AP enabled systems return activity data that we don't expect here.
 963                 if (strpos($curlResult->getContentType(), 'application/activity+json') !== false) {
 964                         return $serverdata;
 965                 }
 966
 967                 $valid = false;
 968                 $old_serverdata = $serverdata;
 969
 970                 $serverdata['detection-method'] = self::DETECT_STATISTICS_JSON;
 971
 972                 if (!empty($data['version'])) {
 973                         $valid = true;
 974                         $serverdata['version'] = $data['version'];
 975                         // Version numbers on statistics.json are presented with additional info, e.g.:
 976                         // 0.6.3.0-p1702cc1c, 0.6.99.0-p1b9ab160 or 3.4.3-2-1191.
 977                         $serverdata['version'] = preg_replace('=(.+)-(.{4,})=ism', '$1', $serverdata['version']);
 978                 }
 979
 980                 if (!empty($data['name'])) {
 981                         $valid = true;
 982                         $serverdata['site_name'] = $data['name'];
 983                 }
 984
 985                 if (!empty($data['network'])) {
 986                         $valid = true;
 987                         $serverdata['platform'] = strtolower($data['network']);
 988
 989                         if ($serverdata['platform'] == 'diaspora') {
 990                                 $serverdata['network'] = Protocol::DIASPORA;
 991                         } elseif ($serverdata['platform'] == 'friendica') {
 992                                 $serverdata['network'] = Protocol::DFRN;
 993                         } elseif ($serverdata['platform'] == 'hubzilla') {
 994                                 $serverdata['network'] = Protocol::ZOT;
 995                         } elseif ($serverdata['platform'] == 'redmatrix') {
 996                                 $serverdata['network'] = Protocol::ZOT;
 997                         }
 998                 }
 999
1000                 if (!empty($data['total_users'])) {
1001                         $valid = true;
1002                         $serverdata['registered-users'] = max($data['total_users'], 1);
1003                 }
1004
1005                 if (!empty($data['active_users_monthly'])) {
1006                         $valid = true;
1007                         $serverdata['active-month-users'] = max($data['active_users_monthly'], 0);
1008                 }
1009
1010                 if (!empty($data['active_users_halfyear'])) {
1011                         $valid = true;
1012                         $serverdata['active-halfyear-users'] = max($data['active_users_halfyear'], 0);
1013                 }
1014
1015                 if (!empty($data['local_posts'])) {
1016                         $valid = true;
1017                         $serverdata['local-posts'] = max($data['local_posts'], 0);
1018                 }
1019
1020                 if (!empty($data['registrations_open'])) {
1021                         $serverdata['register_policy'] = Register::OPEN;
1022                 } else {
1023                         $serverdata['register_policy'] = Register::CLOSED;
1024                 }
1025
1026                 if (!$valid) {
1027                         return $old_serverdata;
1028                 }
1029
1030                 return $serverdata;
1031         }
1032
1033         /**
1034          * Detect server type by using the nodeinfo data
1035          *
1036          * @param string                  $url        address of the server
1037          * @param ICanHandleHttpResponses $httpResult
1038          *
1039          * @return array Server data
1040          *
1041          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1042          */
1043         private static function fetchNodeinfo(string $url, ICanHandleHttpResponses $httpResult): array
1044         {
1045                 if (!$httpResult->isSuccess()) {
1046                         return [];
1047                 }
1048
1049                 $nodeinfo = json_decode($httpResult->getBody(), true);
1050
1051                 if (!is_array($nodeinfo) || empty($nodeinfo['links'])) {
1052                         return [];
1053                 }
1054
1055                 $nodeinfo1_url = '';
1056                 $nodeinfo2_url = '';
1057
1058                 foreach ($nodeinfo['links'] as $link) {
1059                         if (!is_array($link) || empty($link['rel']) || empty($link['href'])) {
1060                                 Logger::info('Invalid nodeinfo format', ['url' => $url]);
1061                                 continue;
1062                         }
1063
1064                         if ($link['rel'] == 'http://nodeinfo.diaspora.software/ns/schema/1.0') {
1065                                 $nodeinfo1_url = Network::addBasePath($link['href'], $httpResult->getUrl());
1066                         } elseif ($link['rel'] == 'http://nodeinfo.diaspora.software/ns/schema/2.0') {
1067                                 $nodeinfo2_url = Network::addBasePath($link['href'], $httpResult->getUrl());
1068                         }
1069                 }
1070
1071                 if ($nodeinfo1_url . $nodeinfo2_url == '') {
1072                         return [];
1073                 }
1074
1075                 $server = [];
1076
1077                 if (!empty($nodeinfo2_url)) {
1078                         $server = self::parseNodeinfo2($nodeinfo2_url);
1079                 }
1080
1081                 if (empty($server) && !empty($nodeinfo1_url)) {
1082                         $server = self::parseNodeinfo1($nodeinfo1_url);
1083                 }
1084
1085                 return $server;
1086         }
1087
1088         /**
1089          * Parses Nodeinfo 1
1090          *
1091          * @param string $nodeinfo_url address of the nodeinfo path
1092          *
1093          * @return array Server data
1094          *
1095          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1096          */
1097         private static function parseNodeinfo1(string $nodeinfo_url): array
1098         {
1099                 $curlResult = DI::httpClient()->get($nodeinfo_url, HttpClientAccept::JSON);
1100                 if (!$curlResult->isSuccess()) {
1101                         return [];
1102                 }
1103
1104                 $nodeinfo = json_decode($curlResult->getBody(), true);
1105
1106                 if (!is_array($nodeinfo)) {
1107                         return [];
1108                 }
1109
1110                 $server = ['detection-method' => self::DETECT_NODEINFO_1,
1111                         'register_policy' => Register::CLOSED];
1112
1113                 if (!empty($nodeinfo['openRegistrations'])) {
1114                         $server['register_policy'] = Register::OPEN;
1115                 }
1116
1117                 if (is_array($nodeinfo['software'])) {
1118                         if (!empty($nodeinfo['software']['name'])) {
1119                                 $server['platform'] = strtolower($nodeinfo['software']['name']);
1120                         }
1121
1122                         if (!empty($nodeinfo['software']['version'])) {
1123                                 $server['version'] = $nodeinfo['software']['version'];
1124                                 // Version numbers on Nodeinfo are presented with additional info, e.g.:
1125                                 // 0.6.3.0-p1702cc1c, 0.6.99.0-p1b9ab160 or 3.4.3-2-1191.
1126                                 $server['version'] = preg_replace('=(.+)-(.{4,})=ism', '$1', $server['version']);
1127                         }
1128                 }
1129
1130                 if (!empty($nodeinfo['metadata']['nodeName'])) {
1131                         $server['site_name'] = $nodeinfo['metadata']['nodeName'];
1132                 }
1133
1134                 if (!empty($nodeinfo['usage']['users']['total'])) {
1135                         $server['registered-users'] = max($nodeinfo['usage']['users']['total'], 1);
1136                 }
1137
1138                 if (!empty($nodeinfo['usage']['users']['activeMonth'])) {
1139                         $server['active-month-users'] = max($nodeinfo['usage']['users']['activeMonth'], 0);
1140                 }
1141
1142                 if (!empty($nodeinfo['usage']['users']['activeHalfyear'])) {
1143                         $server['active-halfyear-users'] = max($nodeinfo['usage']['users']['activeHalfyear'], 0);
1144                 }
1145
1146                 if (!empty($nodeinfo['usage']['localPosts'])) {
1147                         $server['local-posts'] = max($nodeinfo['usage']['localPosts'], 0);
1148                 }
1149
1150                 if (!empty($nodeinfo['usage']['localComments'])) {
1151                         $server['local-comments'] = max($nodeinfo['usage']['localComments'], 0);
1152                 }
1153
1154                 if (!empty($nodeinfo['protocols']['inbound']) && is_array($nodeinfo['protocols']['inbound'])) {
1155                         $protocols = [];
1156                         foreach ($nodeinfo['protocols']['inbound'] as $protocol) {
1157                                 $protocols[$protocol] = true;
1158                         }
1159
1160                         if (!empty($protocols['friendica'])) {
1161                                 $server['network'] = Protocol::DFRN;
1162                         } elseif (!empty($protocols['activitypub'])) {
1163                                 $server['network'] = Protocol::ACTIVITYPUB;
1164                         } elseif (!empty($protocols['diaspora'])) {
1165                                 $server['network'] = Protocol::DIASPORA;
1166                         } elseif (!empty($protocols['ostatus'])) {
1167                                 $server['network'] = Protocol::OSTATUS;
1168                         } elseif (!empty($protocols['gnusocial'])) {
1169                                 $server['network'] = Protocol::OSTATUS;
1170                         } elseif (!empty($protocols['zot'])) {
1171                                 $server['network'] = Protocol::ZOT;
1172                         }
1173                 }
1174
1175                 if (empty($server)) {
1176                         return [];
1177                 }
1178
1179                 if (empty($server['network'])) {
1180                         $server['network'] = Protocol::PHANTOM;
1181                 }
1182
1183                 return $server;
1184         }
1185
1186         /**
1187          * Parses Nodeinfo 2
1188          *
1189          * @see https://git.feneas.org/jaywink/nodeinfo2
1190          *
1191          * @param string $nodeinfo_url address of the nodeinfo path
1192          *
1193          * @return array Server data
1194          *
1195          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1196          */
1197         private static function parseNodeinfo2(string $nodeinfo_url): array
1198         {
1199                 $curlResult = DI::httpClient()->get($nodeinfo_url, HttpClientAccept::JSON);
1200                 if (!$curlResult->isSuccess()) {
1201                         return [];
1202                 }
1203
1204                 $nodeinfo = json_decode($curlResult->getBody(), true);
1205                 if (!is_array($nodeinfo)) {
1206                         return [];
1207                 }
1208
1209                 $server = [
1210                         'detection-method' => self::DETECT_NODEINFO_2,
1211                         'register_policy' => Register::CLOSED,
1212                         'platform' => 'unknown',
1213                 ];
1214
1215                 if (!empty($nodeinfo['openRegistrations'])) {
1216                         $server['register_policy'] = Register::OPEN;
1217                 }
1218
1219                 if (!empty($nodeinfo['software'])) {
1220                         if (isset($nodeinfo['software']['name'])) {
1221                                 $server['platform'] = strtolower($nodeinfo['software']['name']);
1222                         }
1223
1224                         if (!empty($nodeinfo['software']['version']) && isset($server['platform'])) {
1225                                 $server['version'] = $nodeinfo['software']['version'];
1226                                 // Version numbers on Nodeinfo are presented with additional info, e.g.:
1227                                 // 0.6.3.0-p1702cc1c, 0.6.99.0-p1b9ab160 or 3.4.3-2-1191.
1228                                 $server['version'] = preg_replace('=(.+)-(.{4,})=ism', '$1', $server['version']);
1229
1230                                 // qoto advertises itself as Mastodon
1231                                 if (($server['platform'] == 'mastodon') && substr($nodeinfo['software']['version'], -5) == '-qoto') {
1232                                         $server['platform'] = 'qoto';
1233                                 }
1234                         }
1235                 }
1236
1237                 if (!empty($nodeinfo['metadata']['nodeName'])) {
1238                         $server['site_name'] = $nodeinfo['metadata']['nodeName'];
1239                 }
1240
1241                 if (!empty($nodeinfo['usage']['users']['total'])) {
1242                         $server['registered-users'] = max($nodeinfo['usage']['users']['total'], 1);
1243                 }
1244
1245                 if (!empty($nodeinfo['usage']['users']['activeMonth'])) {
1246                         $server['active-month-users'] = max($nodeinfo['usage']['users']['activeMonth'], 0);
1247                 }
1248
1249                 if (!empty($nodeinfo['usage']['users']['activeHalfyear'])) {
1250                         $server['active-halfyear-users'] = max($nodeinfo['usage']['users']['activeHalfyear'], 0);
1251                 }
1252
1253                 if (!empty($nodeinfo['usage']['localPosts'])) {
1254                         $server['local-posts'] = max($nodeinfo['usage']['localPosts'], 0);
1255                 }
1256
1257                 if (!empty($nodeinfo['usage']['localComments'])) {
1258                         $server['local-comments'] = max($nodeinfo['usage']['localComments'], 0);
1259                 }
1260
1261                 if (!empty($nodeinfo['protocols'])) {
1262                         $protocols = [];
1263                         foreach ($nodeinfo['protocols'] as $protocol) {
1264                                 if (is_string($protocol)) {
1265                                         $protocols[$protocol] = true;
1266                                 }
1267                         }
1268
1269                         if (!empty($protocols['dfrn'])) {
1270                                 $server['network'] = Protocol::DFRN;
1271                         } elseif (!empty($protocols['activitypub'])) {
1272                                 $server['network'] = Protocol::ACTIVITYPUB;
1273                         } elseif (!empty($protocols['diaspora'])) {
1274                                 $server['network'] = Protocol::DIASPORA;
1275                         } elseif (!empty($protocols['ostatus'])) {
1276                                 $server['network'] = Protocol::OSTATUS;
1277                         } elseif (!empty($protocols['gnusocial'])) {
1278                                 $server['network'] = Protocol::OSTATUS;
1279                         } elseif (!empty($protocols['zot'])) {
1280                                 $server['network'] = Protocol::ZOT;
1281                         }
1282                 }
1283
1284                 if (empty($server)) {
1285                         return [];
1286                 }
1287
1288                 if (empty($server['network'])) {
1289                         $server['network'] = Protocol::PHANTOM;
1290                 }
1291
1292                 return $server;
1293         }
1294
1295         /**
1296          * Parses NodeInfo2 protocol 1.0
1297          *
1298          * @see https://github.com/jaywink/nodeinfo2/blob/master/PROTOCOL.md
1299          *
1300          * @param string $nodeinfo_url address of the nodeinfo path
1301          *
1302          * @return array Server data
1303          *
1304          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1305          */
1306         private static function parseNodeinfo210(ICanHandleHttpResponses $httpResult): array
1307         {
1308                 if (!$httpResult->isSuccess()) {
1309                         return [];
1310                 }
1311
1312                 $nodeinfo = json_decode($httpResult->getBody(), true);
1313
1314                 if (!is_array($nodeinfo)) {
1315                         return [];
1316                 }
1317
1318                 $server = ['detection-method' => self::DETECT_NODEINFO_210,
1319                         'register_policy' => Register::CLOSED];
1320
1321                 if (!empty($nodeinfo['openRegistrations'])) {
1322                         $server['register_policy'] = Register::OPEN;
1323                 }
1324
1325                 if (!empty($nodeinfo['server'])) {
1326                         if (!empty($nodeinfo['server']['software'])) {
1327                                 $server['platform'] = strtolower($nodeinfo['server']['software']);
1328                         }
1329
1330                         if (!empty($nodeinfo['server']['version'])) {
1331                                 $server['version'] = $nodeinfo['server']['version'];
1332                                 // Version numbers on Nodeinfo are presented with additional info, e.g.:
1333                                 // 0.6.3.0-p1702cc1c, 0.6.99.0-p1b9ab160 or 3.4.3-2-1191.
1334                                 $server['version'] = preg_replace('=(.+)-(.{4,})=ism', '$1', $server['version']);
1335                         }
1336
1337                         if (!empty($nodeinfo['server']['name'])) {
1338                                 $server['site_name'] = $nodeinfo['server']['name'];
1339                         }
1340                 }
1341
1342                 if (!empty($nodeinfo['usage']['users']['total'])) {
1343                         $server['registered-users'] = max($nodeinfo['usage']['users']['total'], 1);
1344                 }
1345
1346                 if (!empty($nodeinfo['usage']['users']['activeMonth'])) {
1347                         $server['active-month-users'] = max($nodeinfo['usage']['users']['activeMonth'], 0);
1348                 }
1349
1350                 if (!empty($nodeinfo['usage']['users']['activeHalfyear'])) {
1351                         $server['active-halfyear-users'] = max($nodeinfo['usage']['users']['activeHalfyear'], 0);
1352                 }
1353
1354                 if (!empty($nodeinfo['usage']['localPosts'])) {
1355                         $server['local-posts'] = max($nodeinfo['usage']['localPosts'], 0);
1356                 }
1357
1358                 if (!empty($nodeinfo['usage']['localComments'])) {
1359                         $server['local-comments'] = max($nodeinfo['usage']['localComments'], 0);
1360                 }
1361
1362                 if (!empty($nodeinfo['protocols'])) {
1363                         $protocols = [];
1364                         foreach ($nodeinfo['protocols'] as $protocol) {
1365                                 if (is_string($protocol)) {
1366                                         $protocols[$protocol] = true;
1367                                 }
1368                         }
1369
1370                         if (!empty($protocols['dfrn'])) {
1371                                 $server['network'] = Protocol::DFRN;
1372                         } elseif (!empty($protocols['activitypub'])) {
1373                                 $server['network'] = Protocol::ACTIVITYPUB;
1374                         } elseif (!empty($protocols['diaspora'])) {
1375                                 $server['network'] = Protocol::DIASPORA;
1376                         } elseif (!empty($protocols['ostatus'])) {
1377                                 $server['network'] = Protocol::OSTATUS;
1378                         } elseif (!empty($protocols['gnusocial'])) {
1379                                 $server['network'] = Protocol::OSTATUS;
1380                         } elseif (!empty($protocols['zot'])) {
1381                                 $server['network'] = Protocol::ZOT;
1382                         }
1383                 }
1384
1385                 if (empty($server) || empty($server['platform'])) {
1386                         return [];
1387                 }
1388
1389                 if (empty($server['network'])) {
1390                         $server['network'] = Protocol::PHANTOM;
1391                 }
1392
1393                 return $server;
1394         }
1395
1396         /**
1397          * Fetch server information from a 'siteinfo.json' file on the given server
1398          *
1399          * @param string $url        URL of the given server
1400          * @param array  $serverdata array with server data
1401          *
1402          * @return array server data
1403          */
1404         private static function fetchSiteinfo(string $url, array $serverdata): array
1405         {
1406                 $curlResult = DI::httpClient()->get($url . '/siteinfo.json', HttpClientAccept::JSON);
1407                 if (!$curlResult->isSuccess()) {
1408                         return $serverdata;
1409                 }
1410
1411                 $data = json_decode($curlResult->getBody(), true);
1412                 if (empty($data)) {
1413                         return $serverdata;
1414                 }
1415
1416                 if (in_array($serverdata['detection-method'], self::DETECT_UNSPECIFIC)) {
1417                         $serverdata['detection-method'] = self::DETECT_SITEINFO_JSON;
1418                 }
1419
1420                 if (!empty($data['platform'])) {
1421                         $serverdata['platform'] = strtolower($data['platform']);
1422                         $serverdata['version'] = $data['version'] ?? 'N/A';
1423                 }
1424
1425                 if (!empty($data['plugins'])) {
1426                         if (in_array('pubcrawl', $data['plugins'])) {
1427                                 $serverdata['network'] = Protocol::ACTIVITYPUB;
1428                         } elseif (in_array('diaspora', $data['plugins'])) {
1429                                 $serverdata['network'] = Protocol::DIASPORA;
1430                         } elseif (in_array('gnusoc', $data['plugins'])) {
1431                                 $serverdata['network'] = Protocol::OSTATUS;
1432                         } else {
1433                                 $serverdata['network'] = Protocol::ZOT;
1434                         }
1435                 }
1436
1437                 if (!empty($data['site_name'])) {
1438                         $serverdata['site_name'] = $data['site_name'];
1439                 }
1440
1441                 if (!empty($data['channels_total'])) {
1442                         $serverdata['registered-users'] = max($data['channels_total'], 1);
1443                 }
1444
1445                 if (!empty($data['channels_active_monthly'])) {
1446                         $serverdata['active-month-users'] = max($data['channels_active_monthly'], 0);
1447                 }
1448
1449                 if (!empty($data['channels_active_halfyear'])) {
1450                         $serverdata['active-halfyear-users'] = max($data['channels_active_halfyear'], 0);
1451                 }
1452
1453                 if (!empty($data['local_posts'])) {
1454                         $serverdata['local-posts'] = max($data['local_posts'], 0);
1455                 }
1456
1457                 if (!empty($data['local_comments'])) {
1458                         $serverdata['local-comments'] = max($data['local_comments'], 0);
1459                 }
1460
1461                 if (!empty($data['register_policy'])) {
1462                         switch ($data['register_policy']) {
1463                                 case 'REGISTER_OPEN':
1464                                         $serverdata['register_policy'] = Register::OPEN;
1465                                         break;
1466
1467                                 case 'REGISTER_APPROVE':
1468                                         $serverdata['register_policy'] = Register::APPROVE;
1469                                         break;
1470
1471                                 case 'REGISTER_CLOSED':
1472                                 default:
1473                                         $serverdata['register_policy'] = Register::CLOSED;
1474                                         break;
1475                         }
1476                 }
1477
1478                 return $serverdata;
1479         }
1480
1481         /**
1482          * Fetches server data via an ActivityPub account with url of that server
1483          *
1484          * @param string $url        URL of the given server
1485          * @param array  $serverdata array with server data
1486          *
1487          * @return array server data
1488          *
1489          * @throws Exception
1490          */
1491         private static function fetchDataFromSystemActor(array $data, array $serverdata): array
1492         {
1493                 if (empty($data)) {
1494                         return ['server' => $serverdata, 'actor' => ''];
1495                 }
1496
1497                 $actor = JsonLD::compact($data, false);
1498                 if (in_array(JsonLD::fetchElement($actor, '@type'), ActivityPub\Receiver::ACCOUNT_TYPES)) {
1499                         $serverdata['network'] = Protocol::ACTIVITYPUB;
1500                         $serverdata['site_name'] = JsonLD::fetchElement($actor, 'as:name', '@value');
1501                         $serverdata['info'] = JsonLD::fetchElement($actor, 'as:summary', '@value');
1502                         if (!empty($actor['as:generator'])) {
1503                                 $generator = explode(' ', JsonLD::fetchElement($actor['as:generator'], 'as:name', '@value'));
1504                                 $serverdata['platform'] = strtolower(array_shift($generator));
1505                                 $serverdata['detection-method'] = self::DETECT_SYSTEM_ACTOR;
1506                                 if (self::isNomad($actor)) {
1507                                         $serverdata['version']  = $serverdata['platform'];
1508                                         $serverdata['platform'] = 'nomad';
1509                                 }
1510                         } else {
1511                                 $serverdata['detection-method'] = self::DETECT_AP_ACTOR;
1512                         }
1513                         return ['server' => $serverdata, 'actor' => $actor['@id']];
1514                 } elseif ((JsonLD::fetchElement($actor, '@type') == 'as:Collection')) {
1515                         // By now only Ktistec seems to provide collections this way
1516                         $serverdata['platform'] = 'ktistec';
1517                         $serverdata['network'] = Protocol::ACTIVITYPUB;
1518                         $serverdata['detection-method'] = self::DETECT_AP_COLLECTION;
1519
1520                         $actors = JsonLD::fetchElementArray($actor, 'as:items');
1521                         if (!empty($actors) && !empty($actors[0]['@id'])) {
1522                                 $actor_url = $actor['@id'] . $actors[0]['@id'];
1523                         } else {
1524                                 $actor_url = '';
1525                         }
1526
1527                         return ['server' => $serverdata, 'actor' => $actor_url];
1528                 }
1529                 return ['server' => $serverdata, 'actor' => ''];
1530         }
1531
1532         /**
1533          * Detect if the given actor is a nomad account
1534          *
1535          * @param array $actor
1536          * @return boolean
1537          */
1538         private static function isNomad(array $actor): bool
1539         {
1540                 $tags = JsonLD::fetchElementArray($actor, 'as:tag');
1541                 if (empty($tags)) {
1542                         return false;
1543                 }
1544
1545                 foreach ($tags as $tag) {
1546                         if ((($tag['as:name'] ?? '') == 'Protocol') && (($tag['sc:value'] ?? '') == 'nomad')) {
1547                                 return true;
1548                         }
1549                 }
1550                 return false;
1551         }
1552
1553         /**
1554          * Checks if the server contains a valid host meta file
1555          *
1556          * @param string $url URL of the given server
1557          *
1558          * @return boolean 'true' if the server seems to be vital
1559          */
1560         private static function validHostMeta(string $url): bool
1561         {
1562                 $xrd_timeout = DI::config()->get('system', 'xrd_timeout');
1563                 $curlResult = DI::httpClient()->get($url . Probe::HOST_META, HttpClientAccept::XRD_XML, [HttpClientOptions::TIMEOUT => $xrd_timeout]);
1564                 if (!$curlResult->isSuccess()) {
1565                         return false;
1566                 }
1567
1568                 $xrd = XML::parseString($curlResult->getBody(), true);
1569                 if (!is_object($xrd)) {
1570                         return false;
1571                 }
1572
1573                 $elements = XML::elementToArray($xrd);
1574                 if (empty($elements) || empty($elements['xrd']) || empty($elements['xrd']['link'])) {
1575                         return false;
1576                 }
1577
1578                 $valid = false;
1579                 foreach ($elements['xrd']['link'] as $link) {
1580                         // When there is more than a single "link" element, the array looks slightly different
1581                         if (!empty($link['@attributes'])) {
1582                                 $link = $link['@attributes'];
1583                         }
1584
1585                         if (empty($link['rel']) || empty($link['template'])) {
1586                                 continue;
1587                         }
1588
1589                         if ($link['rel'] == 'lrdd') {
1590                                 // When the webfinger host is the same like the system host, it should be ok.
1591                                 $valid = (parse_url($url, PHP_URL_HOST) == parse_url($link['template'], PHP_URL_HOST));
1592                         }
1593                 }
1594
1595                 return $valid;
1596         }
1597
1598         /**
1599          * Detect the network of the given server via their known contacts
1600          *
1601          * @param string $url        URL of the given server
1602          * @param array  $serverdata array with server data
1603          *
1604          * @return array server data
1605          */
1606         private static function detectNetworkViaContacts(string $url, array $serverdata): array
1607         {
1608                 $contacts = [];
1609
1610                 $nurl = Strings::normaliseLink($url);
1611
1612                 $apcontacts = DBA::select('apcontact', ['url'], ['baseurl' => [$url, $nurl]]);
1613                 while ($apcontact = DBA::fetch($apcontacts)) {
1614                         $contacts[Strings::normaliseLink($apcontact['url'])] = $apcontact['url'];
1615                 }
1616                 DBA::close($apcontacts);
1617
1618                 $pcontacts = DBA::select('contact', ['url', 'nurl'], ['uid' => 0, 'baseurl' => [$url, $nurl]]);
1619                 while ($pcontact = DBA::fetch($pcontacts)) {
1620                         $contacts[$pcontact['nurl']] = $pcontact['url'];
1621                 }
1622                 DBA::close($pcontacts);
1623
1624                 if (empty($contacts)) {
1625                         return $serverdata;
1626                 }
1627
1628                 $time = time();
1629                 foreach ($contacts as $contact) {
1630                         // Endlosschleife verhindern wegen gsid!
1631                         $data = Probe::uri($contact);
1632                         if (in_array($data['network'], Protocol::FEDERATED)) {
1633                                 $serverdata['network'] = $data['network'];
1634
1635                                 if (in_array($serverdata['detection-method'], self::DETECT_UNSPECIFIC)) {
1636                                         $serverdata['detection-method'] = self::DETECT_CONTACTS;
1637                                 }
1638                                 break;
1639                         } elseif ((time() - $time) > 10) {
1640                                 // To reduce the stress on remote systems we probe a maximum of 10 seconds
1641                                 break;
1642                         }
1643                 }
1644
1645                 return $serverdata;
1646         }
1647
1648         /**
1649          * Checks if the given server does have a '/poco' endpoint.
1650          * This is used for the 'PortableContact' functionality,
1651          * which is used by both Friendica and Hubzilla.
1652          *
1653          * @param string $url        URL of the given server
1654          * @param array  $serverdata array with server data
1655          *
1656          * @return array server data
1657          */
1658         private static function checkPoCo(string $url, array $serverdata): array
1659         {
1660                 $serverdata['poco'] = '';
1661
1662                 $curlResult = DI::httpClient()->get($url . '/poco', HttpClientAccept::JSON);
1663                 if (!$curlResult->isSuccess()) {
1664                         return $serverdata;
1665                 }
1666
1667                 $data = json_decode($curlResult->getBody(), true);
1668                 if (empty($data)) {
1669                         return $serverdata;
1670                 }
1671
1672                 if (!empty($data['totalResults'])) {
1673                         $registeredUsers = $serverdata['registered-users'] ?? 0;
1674                         $serverdata['registered-users'] = max($data['totalResults'], $registeredUsers, 1);
1675                         $serverdata['directory-type'] = self::DT_POCO;
1676                         $serverdata['poco'] = $url . '/poco';
1677                 }
1678
1679                 return $serverdata;
1680         }
1681
1682         /**
1683          * Checks if the given server does have a Mastodon style directory endpoint.
1684          *
1685          * @param string $url        URL of the given server
1686          * @param array  $serverdata array with server data
1687          *
1688          * @return array server data
1689          */
1690         public static function checkMastodonDirectory(string $url, array $serverdata): array
1691         {
1692                 $curlResult = DI::httpClient()->get($url . '/api/v1/directory?limit=1', HttpClientAccept::JSON);
1693                 if (!$curlResult->isSuccess()) {
1694                         return $serverdata;
1695                 }
1696
1697                 $data = json_decode($curlResult->getBody(), true);
1698                 if (empty($data)) {
1699                         return $serverdata;
1700                 }
1701
1702                 if (count($data) == 1) {
1703                         $serverdata['directory-type'] = self::DT_MASTODON;
1704                 }
1705
1706                 return $serverdata;
1707         }
1708
1709         /**
1710          * Detects Peertube via their known endpoint
1711          *
1712          * @param string $url        URL of the given server
1713          * @param array  $serverdata array with server data
1714          *
1715          * @return array server data
1716          */
1717         private static function detectPeertube(string $url, array $serverdata): array
1718         {
1719                 $curlResult = DI::httpClient()->get($url . '/api/v1/config', HttpClientAccept::JSON);
1720                 if (!$curlResult->isSuccess() || ($curlResult->getBody() == '')) {
1721                         return $serverdata;
1722                 }
1723
1724                 $data = json_decode($curlResult->getBody(), true);
1725                 if (empty($data)) {
1726                         return $serverdata;
1727                 }
1728
1729                 if (!empty($data['instance']) && !empty($data['serverVersion'])) {
1730                         $serverdata['platform'] = 'peertube';
1731                         $serverdata['version'] = $data['serverVersion'];
1732                         $serverdata['network'] = Protocol::ACTIVITYPUB;
1733
1734                         if (!empty($data['instance']['name'])) {
1735                                 $serverdata['site_name'] = $data['instance']['name'];
1736                         }
1737
1738                         if (!empty($data['instance']['shortDescription'])) {
1739                                 $serverdata['info'] = $data['instance']['shortDescription'];
1740                         }
1741
1742                         if (!empty($data['signup'])) {
1743                                 if (!empty($data['signup']['allowed'])) {
1744                                         $serverdata['register_policy'] = Register::OPEN;
1745                                 }
1746                         }
1747
1748                         if (in_array($serverdata['detection-method'], self::DETECT_UNSPECIFIC)) {
1749                                 $serverdata['detection-method'] = self::DETECT_V1_CONFIG;
1750                         }
1751                 }
1752
1753                 return $serverdata;
1754         }
1755
1756         /**
1757          * Detects the version number of a given server when it was a NextCloud installation
1758          *
1759          * @param string $url        URL of the given server
1760          * @param array  $serverdata array with server data
1761          * @param bool   $validHostMeta
1762          *
1763          * @return array server data
1764          */
1765         private static function detectNextcloud(string $url, array $serverdata, bool $validHostMeta): array
1766         {
1767                 $curlResult = DI::httpClient()->get($url . '/status.php', HttpClientAccept::JSON);
1768                 if (!$curlResult->isSuccess() || ($curlResult->getBody() == '')) {
1769                         return $serverdata;
1770                 }
1771
1772                 $data = json_decode($curlResult->getBody(), true);
1773                 if (empty($data)) {
1774                         return $serverdata;
1775                 }
1776
1777                 if (!empty($data['version'])) {
1778                         $serverdata['platform'] = 'nextcloud';
1779                         $serverdata['version'] = $data['version'];
1780
1781                         if ($validHostMeta) {
1782                                 $serverdata['network'] = Protocol::ACTIVITYPUB;
1783                         }
1784
1785                         if (in_array($serverdata['detection-method'], self::DETECT_UNSPECIFIC)) {
1786                                 $serverdata['detection-method'] = self::DETECT_STATUS_PHP;
1787                         }
1788                 }
1789
1790                 return $serverdata;
1791         }
1792
1793         /**
1794          * Fetches weekly usage data
1795          *
1796          * @param string $url        URL of the given server
1797          * @param array  $serverdata array with server data
1798          *
1799          * @return array server data
1800          */
1801         private static function fetchWeeklyUsage(string $url, array $serverdata): array
1802         {
1803                 $curlResult = DI::httpClient()->get($url . '/api/v1/instance/activity', HttpClientAccept::JSON);
1804                 if (!$curlResult->isSuccess() || ($curlResult->getBody() == '')) {
1805                         return $serverdata;
1806                 }
1807
1808                 $data = json_decode($curlResult->getBody(), true);
1809                 if (empty($data)) {
1810                         return $serverdata;
1811                 }
1812
1813                 $current_week = [];
1814                 foreach ($data as $week) {
1815                         // Use only data from a full week
1816                         if (empty($week['week']) || (time() - $week['week']) < 7 * 24 * 60 * 60) {
1817                                 continue;
1818                         }
1819
1820                         // Most likely the data is sorted correctly. But we better are safe than sorry
1821                         if (empty($current_week['week']) || ($current_week['week'] < $week['week'])) {
1822                                 $current_week = $week;
1823                         }
1824                 }
1825
1826                 if (!empty($current_week['logins'])) {
1827                         $serverdata['active-week-users'] = max($current_week['logins'], 0);
1828                 }
1829
1830                 return $serverdata;
1831         }
1832
1833         /**
1834          * Detects data from a given server url if it was a mastodon alike system
1835          *
1836          * @param string $url        URL of the given server
1837          * @param array  $serverdata array with server data
1838          *
1839          * @return array server data
1840          */
1841         private static function detectMastodonAlikes(string $url, array $serverdata): array
1842         {
1843                 $curlResult = DI::httpClient()->get($url . '/api/v1/instance', HttpClientAccept::JSON);
1844                 if (!$curlResult->isSuccess() || ($curlResult->getBody() == '')) {
1845                         return $serverdata;
1846                 }
1847
1848                 $data = json_decode($curlResult->getBody(), true);
1849                 if (empty($data)) {
1850                         return $serverdata;
1851                 }
1852
1853                 $valid = false;
1854
1855                 if (!empty($data['version'])) {
1856                         $serverdata['platform'] = 'mastodon';
1857                         $serverdata['version'] = $data['version'] ?? '';
1858                         $serverdata['network'] = Protocol::ACTIVITYPUB;
1859                         $valid = true;
1860                 }
1861
1862                 if (!empty($data['title'])) {
1863                         $serverdata['site_name'] = $data['title'];
1864                 }
1865
1866                 if (!empty($data['title']) && empty($serverdata['platform']) && ($serverdata['network'] == Protocol::PHANTOM)) {
1867                         $serverdata['platform'] = 'mastodon';
1868                         $serverdata['network'] = Protocol::ACTIVITYPUB;
1869                         $valid = true;
1870                 }
1871
1872                 if (!empty($data['description'])) {
1873                         $serverdata['info'] = trim($data['description']);
1874                 }
1875
1876                 if (!empty($data['stats']['user_count'])) {
1877                         $serverdata['registered-users'] = max($data['stats']['user_count'], 1);
1878                 }
1879
1880                 if (!empty($serverdata['version']) && preg_match('/.*?\(compatible;\s(.*)\s(.*)\)/ism', $serverdata['version'], $matches)) {
1881                         $serverdata['platform'] = strtolower($matches[1]);
1882                         $serverdata['version'] = $matches[2];
1883                         $valid = true;
1884                 }
1885
1886                 if (!empty($serverdata['version']) && strstr(strtolower($serverdata['version']), 'pleroma')) {
1887                         $serverdata['platform'] = 'pleroma';
1888                         $serverdata['version'] = trim(str_ireplace('pleroma', '', $serverdata['version']));
1889                         $valid = true;
1890                 }
1891
1892                 if (!empty($serverdata['platform']) && strstr($serverdata['platform'], 'pleroma')) {
1893                         $serverdata['version'] = trim(str_ireplace('pleroma', '', $serverdata['platform']));
1894                         $serverdata['platform'] = 'pleroma';
1895                         $valid = true;
1896                 }
1897
1898                 if ($valid && in_array($serverdata['detection-method'], self::DETECT_UNSPECIFIC)) {
1899                         $serverdata['detection-method'] = self::DETECT_MASTODON_API;
1900                 }
1901
1902                 return $serverdata;
1903         }
1904
1905         /**
1906          * Detects data from typical Hubzilla endpoints
1907          *
1908          * @param string $url        URL of the given server
1909          * @param array  $serverdata array with server data
1910          *
1911          * @return array server data
1912          */
1913         private static function detectHubzilla(string $url, array $serverdata): array
1914         {
1915                 $curlResult = DI::httpClient()->get($url . '/api/statusnet/config.json', HttpClientAccept::JSON);
1916                 if (!$curlResult->isSuccess() || ($curlResult->getBody() == '')) {
1917                         return $serverdata;
1918                 }
1919
1920                 $data = json_decode($curlResult->getBody(), true);
1921                 if (empty($data) || empty($data['site'])) {
1922                         return $serverdata;
1923                 }
1924
1925                 if (!empty($data['site']['name'])) {
1926                         $serverdata['site_name'] = $data['site']['name'];
1927                 }
1928
1929                 if (!empty($data['site']['platform'])) {
1930                         $serverdata['platform'] = strtolower($data['site']['platform']['PLATFORM_NAME']);
1931                         $serverdata['version'] = $data['site']['platform']['STD_VERSION'];
1932                         $serverdata['network'] = Protocol::ZOT;
1933                 }
1934
1935                 if (!empty($data['site']['hubzilla'])) {
1936                         $serverdata['platform'] = strtolower($data['site']['hubzilla']['PLATFORM_NAME']);
1937                         $serverdata['version'] = $data['site']['hubzilla']['RED_VERSION'];
1938                         $serverdata['network'] = Protocol::ZOT;
1939                 }
1940
1941                 if (!empty($data['site']['redmatrix'])) {
1942                         if (!empty($data['site']['redmatrix']['PLATFORM_NAME'])) {
1943                                 $serverdata['platform'] = strtolower($data['site']['redmatrix']['PLATFORM_NAME']);
1944                         } elseif (!empty($data['site']['redmatrix']['RED_PLATFORM'])) {
1945                                 $serverdata['platform'] = strtolower($data['site']['redmatrix']['RED_PLATFORM']);
1946                         }
1947
1948                         $serverdata['version'] = $data['site']['redmatrix']['RED_VERSION'];
1949                         $serverdata['network'] = Protocol::ZOT;
1950                 }
1951
1952                 $private = false;
1953                 $inviteonly = false;
1954                 $closed = false;
1955
1956                 if (!empty($data['site']['closed'])) {
1957                         $closed = self::toBoolean($data['site']['closed']);
1958                 }
1959
1960                 if (!empty($data['site']['private'])) {
1961                         $private = self::toBoolean($data['site']['private']);
1962                 }
1963
1964                 if (!empty($data['site']['inviteonly'])) {
1965                         $inviteonly = self::toBoolean($data['site']['inviteonly']);
1966                 }
1967
1968                 if (!$closed && !$private and $inviteonly) {
1969                         $serverdata['register_policy'] = Register::APPROVE;
1970                 } elseif (!$closed && !$private) {
1971                         $serverdata['register_policy'] = Register::OPEN;
1972                 } else {
1973                         $serverdata['register_policy'] = Register::CLOSED;
1974                 }
1975
1976                 if (($serverdata['network'] != Protocol::PHANTOM) && in_array($serverdata['detection-method'], self::DETECT_UNSPECIFIC)) {
1977                         $serverdata['detection-method'] = self::DETECT_CONFIG_JSON;
1978                 }
1979
1980                 return $serverdata;
1981         }
1982
1983         /**
1984          * Converts input value to a boolean value
1985          *
1986          * @param string|integer $val
1987          *
1988          * @return boolean
1989          */
1990         private static function toBoolean($val): bool
1991         {
1992                 if (($val == 'true') || ($val == 1)) {
1993                         return true;
1994                 } elseif (($val == 'false') || ($val == 0)) {
1995                         return false;
1996                 }
1997
1998                 return $val;
1999         }
2000
2001         /**
2002          * Detect if the URL belongs to a GNU Social server
2003          *
2004          * @param string $url        URL of the given server
2005          * @param array  $serverdata array with server data
2006          *
2007          * @return array server data
2008          */
2009         private static function detectGNUSocial(string $url, array $serverdata): array
2010         {
2011                 // Test for GNU Social
2012                 $curlResult = DI::httpClient()->get($url . '/api/gnusocial/version.json', HttpClientAccept::JSON);
2013                 if ($curlResult->isSuccess() && ($curlResult->getBody() != '{"error":"not implemented"}') &&
2014                         ($curlResult->getBody() != '') && (strlen($curlResult->getBody()) < 30)) {
2015                         $serverdata['platform'] = 'gnusocial';
2016                         // Remove junk that some GNU Social servers return
2017                         $serverdata['version'] = str_replace(chr(239) . chr(187) . chr(191), '', $curlResult->getBody());
2018                         $serverdata['version'] = str_replace(["\r", "\n", "\t"], '', $serverdata['version']);
2019                         $serverdata['version'] = trim($serverdata['version'], '"');
2020                         $serverdata['network'] = Protocol::OSTATUS;
2021
2022                         if (in_array($serverdata['detection-method'], self::DETECT_UNSPECIFIC)) {
2023                                 $serverdata['detection-method'] = self::DETECT_GNUSOCIAL;
2024                         }
2025
2026                         return $serverdata;
2027                 }
2028
2029                 // Test for Statusnet
2030                 $curlResult = DI::httpClient()->get($url . '/api/statusnet/version.json', HttpClientAccept::JSON);
2031                 if ($curlResult->isSuccess() && ($curlResult->getBody() != '{"error":"not implemented"}') &&
2032                         ($curlResult->getBody() != '') && (strlen($curlResult->getBody()) < 30)) {
2033
2034                         // Remove junk that some GNU Social servers return
2035                         $serverdata['version'] = str_replace(chr(239).chr(187).chr(191), '', $curlResult->getBody());
2036                         $serverdata['version'] = str_replace(["\r", "\n", "\t"], '', $serverdata['version']);
2037                         $serverdata['version'] = trim($serverdata['version'], '"');
2038
2039                         if (!empty($serverdata['version']) && strtolower(substr($serverdata['version'], 0, 7)) == 'pleroma') {
2040                                 $serverdata['platform'] = 'pleroma';
2041                                 $serverdata['version'] = trim(str_ireplace('pleroma', '', $serverdata['version']));
2042                                 $serverdata['network'] = Protocol::ACTIVITYPUB;
2043                         } else {
2044                                 $serverdata['platform'] = 'statusnet';
2045                                 $serverdata['network'] = Protocol::OSTATUS;
2046                         }
2047
2048                         if (in_array($serverdata['detection-method'], self::DETECT_UNSPECIFIC)) {
2049                                 $serverdata['detection-method'] = self::DETECT_STATUSNET;
2050                         }
2051                 }
2052
2053                 return $serverdata;
2054         }
2055
2056         /**
2057          * Detect if the URL belongs to a Friendica server
2058          *
2059          * @param string $url        URL of the given server
2060          * @param array  $serverdata array with server data
2061          *
2062          * @return array server data
2063          */
2064         private static function detectFriendica(string $url, array $serverdata): array
2065         {
2066                 // There is a bug in some versions of Friendica that will return an ActivityStream actor when the content type "application/json" is requested.
2067                 // Because of this me must not use ACCEPT_JSON here.
2068                 $curlResult = DI::httpClient()->get($url . '/friendica/json');
2069                 if (!$curlResult->isSuccess()) {
2070                         $curlResult = DI::httpClient()->get($url . '/friendika/json');
2071                         $friendika = true;
2072                         $platform = 'Friendika';
2073                 } else {
2074                         $friendika = false;
2075                         $platform = 'Friendica';
2076                 }
2077
2078                 if (!$curlResult->isSuccess()) {
2079                         return $serverdata;
2080                 }
2081
2082                 $data = json_decode($curlResult->getBody(), true);
2083                 if (empty($data) || empty($data['version'])) {
2084                         return $serverdata;
2085                 }
2086
2087                 if (in_array($serverdata['detection-method'], self::DETECT_UNSPECIFIC)) {
2088                         $serverdata['detection-method'] = $friendika ? self::DETECT_FRIENDIKA : self::DETECT_FRIENDICA;
2089                 }
2090
2091                 $serverdata['network'] = Protocol::DFRN;
2092                 $serverdata['version'] = $data['version'];
2093
2094                 if (!empty($data['no_scrape_url'])) {
2095                         $serverdata['noscrape'] = $data['no_scrape_url'];
2096                 }
2097
2098                 if (!empty($data['site_name'])) {
2099                         $serverdata['site_name'] = $data['site_name'];
2100                 }
2101
2102                 if (!empty($data['info'])) {
2103                         $serverdata['info'] = trim($data['info']);
2104                 }
2105
2106                 $register_policy = ($data['register_policy'] ?? '') ?: 'REGISTER_CLOSED';
2107                 switch ($register_policy) {
2108                         case 'REGISTER_OPEN':
2109                                 $serverdata['register_policy'] = Register::OPEN;
2110                                 break;
2111
2112                         case 'REGISTER_APPROVE':
2113                                 $serverdata['register_policy'] = Register::APPROVE;
2114                                 break;
2115
2116                         case 'REGISTER_CLOSED':
2117                         case 'REGISTER_INVITATION':
2118                                 $serverdata['register_policy'] = Register::CLOSED;
2119                                 break;
2120                         default:
2121                                 Logger::info('Register policy is invalid', ['policy' => $register_policy, 'server' => $url]);
2122                                 $serverdata['register_policy'] = Register::CLOSED;
2123                                 break;
2124                 }
2125
2126                 $serverdata['platform'] = strtolower($data['platform'] ?? $platform);
2127
2128                 return $serverdata;
2129         }
2130
2131         /**
2132          * Analyses the landing page of a given server for hints about type and system of that server
2133          *
2134          * @param object $curlResult result of curl execution
2135          * @param array  $serverdata array with server data
2136          *
2137          * @return array server data
2138          */
2139         private static function analyseRootBody($curlResult, array $serverdata): array
2140         {
2141                 if (empty($curlResult->getBody())) {
2142                         return $serverdata;
2143                 }
2144
2145                 if (file_exists(__DIR__ . '/../../static/platforms.config.php')) {
2146                         require __DIR__ . '/../../static/platforms.config.php';
2147                 } else {
2148                         throw new HTTPException\InternalServerErrorException('Invalid platform file');
2149                 }
2150
2151                 $platforms = array_merge($ap_platforms, $dfrn_platforms, $zap_platforms, $platforms);
2152
2153                 $doc = new DOMDocument();
2154                 @$doc->loadHTML($curlResult->getBody());
2155                 $xpath = new DOMXPath($doc);
2156                 $assigned = false;
2157
2158                 // We can only detect honk via some HTML element on their page
2159                 if ($xpath->query('//div[@id="honksonpage"]')->count() == 1) {
2160                         $serverdata['platform'] = 'honk';
2161                         $serverdata['network'] = Protocol::ACTIVITYPUB;
2162                         $assigned = true;
2163                 }
2164
2165                 $title = trim(XML::getFirstNodeValue($xpath, '//head/title/text()'));
2166                 if (!empty($title)) {
2167                         $serverdata['site_name'] = $title;
2168                 }
2169
2170                 $list = $xpath->query('//meta[@name]');
2171
2172                 foreach ($list as $node) {
2173                         $attr = [];
2174                         if ($node->attributes->length) {
2175                                 foreach ($node->attributes as $attribute) {
2176                                         $value = trim($attribute->value);
2177                                         if (empty($value)) {
2178                                                 continue;
2179                                         }
2180
2181                                         $attr[$attribute->name] = $value;
2182                                 }
2183
2184                                 if (empty($attr['name']) || empty($attr['content'])) {
2185                                         continue;
2186                                 }
2187                         }
2188
2189                         if ($attr['name'] == 'description') {
2190                                 $serverdata['info'] = $attr['content'];
2191                         }
2192
2193                         if (in_array($attr['name'], ['application-name', 'al:android:app_name', 'al:ios:app_name',
2194                                 'twitter:app:name:googleplay', 'twitter:app:name:iphone', 'twitter:app:name:ipad', 'generator'])) {
2195                                 $platform = str_ireplace(array_keys($platforms), array_values($platforms), $attr['content']);
2196                                 $platform = str_replace('/', ' ', $platform);
2197                                 $platform_parts = explode(' ', $platform);
2198                                 if ((count($platform_parts) >= 2) && in_array(strtolower($platform_parts[0]), array_values($platforms))) {
2199                                         $platform = $platform_parts[0];
2200                                         $serverdata['version'] = $platform_parts[1];
2201                                 }
2202                                 if (in_array($platform, array_values($dfrn_platforms))) {
2203                                         $serverdata['network'] = Protocol::DFRN;
2204                                 } elseif (in_array($platform, array_values($ap_platforms))) {
2205                                         $serverdata['network'] = Protocol::ACTIVITYPUB;
2206                                 } elseif (in_array($platform, array_values($zap_platforms))) {
2207                                         $serverdata['network'] = Protocol::ZOT;
2208                                 }
2209                                 if (in_array($platform, array_values($platforms))) {
2210                                         $serverdata['platform'] = $platform;
2211                                         $assigned = true;
2212                                 }
2213                         }
2214                 }
2215
2216                 $list = $xpath->query('//meta[@property]');
2217
2218                 foreach ($list as $node) {
2219                         $attr = [];
2220                         if ($node->attributes->length) {
2221                                 foreach ($node->attributes as $attribute) {
2222                                         $value = trim($attribute->value);
2223                                         if (empty($value)) {
2224                                                 continue;
2225                                         }
2226
2227                                         $attr[$attribute->name] = $value;
2228                                 }
2229
2230                                 if (empty($attr['property']) || empty($attr['content'])) {
2231                                         continue;
2232                                 }
2233                         }
2234
2235                         if ($attr['property'] == 'og:site_name') {
2236                                 $serverdata['site_name'] = $attr['content'];
2237                         }
2238
2239                         if ($attr['property'] == 'og:description') {
2240                                 $serverdata['info'] = $attr['content'];
2241                         }
2242
2243                         if (in_array($attr['property'], ['og:platform', 'generator'])) {
2244                                 if (in_array($attr['content'], array_keys($platforms))) {
2245                                         $serverdata['platform'] = $platforms[$attr['content']];
2246                                         $assigned = true;
2247                                 }
2248
2249                                 if (in_array($attr['content'], array_keys($ap_platforms))) {
2250                                         $serverdata['network'] = Protocol::ACTIVITYPUB;
2251                                 } elseif (in_array($attr['content'], array_values($zap_platforms))) {
2252                                         $serverdata['network'] = Protocol::ZOT;
2253                                 }
2254                         }
2255                 }
2256
2257                 $list = $xpath->query('//link[@rel="me"]');
2258                 foreach ($list as $node) {
2259                         foreach ($node->attributes as $attribute) {
2260                                 if (parse_url(trim($attribute->value), PHP_URL_HOST) == 'micro.blog') {
2261                                         $serverdata['version'] = trim($serverdata['platform'] . ' ' . $serverdata['version']);
2262                                         $serverdata['platform'] = 'microblog';
2263                                         $serverdata['network'] = Protocol::ACTIVITYPUB;
2264                                         $assigned = true;
2265                                 }
2266                         }
2267                 }
2268
2269                 if ($serverdata['platform'] != 'microblog') {
2270                         $list = $xpath->query('//link[@rel="micropub"]');
2271                         foreach ($list as $node) {
2272                                 foreach ($node->attributes as $attribute) {
2273                                         if (trim($attribute->value) == 'https://micro.blog/micropub') {
2274                                                 $serverdata['version'] = trim($serverdata['platform'] . ' ' . $serverdata['version']);
2275                                                 $serverdata['platform'] = 'microblog';
2276                                                 $serverdata['network'] = Protocol::ACTIVITYPUB;
2277                                                 $assigned = true;
2278                                         }
2279                                 }
2280                         }
2281                 }
2282
2283                 if ($assigned && in_array($serverdata['detection-method'], [self::DETECT_MANUAL, self::DETECT_HEADER])) {
2284                         $serverdata['detection-method'] = self::DETECT_BODY;
2285                 }
2286
2287                 return $serverdata;
2288         }
2289
2290         /**
2291          * Analyses the header data of a given server for hints about type and system of that server
2292          *
2293          * @param object $curlResult result of curl execution
2294          * @param array  $serverdata array with server data
2295          *
2296          * @return array server data
2297          */
2298         private static function analyseRootHeader($curlResult, array $serverdata): array
2299         {
2300                 if ($curlResult->getHeader('server') == 'Mastodon') {
2301                         $serverdata['platform'] = 'mastodon';
2302                         $serverdata['network'] = Protocol::ACTIVITYPUB;
2303                 } elseif ($curlResult->inHeader('x-diaspora-version')) {
2304                         $serverdata['platform'] = 'diaspora';
2305                         $serverdata['network'] = Protocol::DIASPORA;
2306                         $serverdata['version'] = $curlResult->getHeader('x-diaspora-version')[0] ?? '';
2307                 } elseif ($curlResult->inHeader('x-friendica-version')) {
2308                         $serverdata['platform'] = 'friendica';
2309                         $serverdata['network'] = Protocol::DFRN;
2310                         $serverdata['version'] = $curlResult->getHeader('x-friendica-version')[0] ?? '';
2311                 } else {
2312                         return $serverdata;
2313                 }
2314
2315                 if ($serverdata['detection-method'] == self::DETECT_MANUAL) {
2316                         $serverdata['detection-method'] = self::DETECT_HEADER;
2317                 }
2318
2319                 return $serverdata;
2320         }
2321
2322         /**
2323          * Update GServer entries
2324          */
2325         public static function discover()
2326         {
2327                 // Update the server list
2328                 self::discoverFederation();
2329
2330                 $no_of_queries = 5;
2331
2332                 $requery_days = intval(DI::config()->get('system', 'poco_requery_days'));
2333
2334                 if ($requery_days == 0) {
2335                         $requery_days = 7;
2336                 }
2337
2338                 $last_update = date('c', time() - (60 * 60 * 24 * $requery_days));
2339
2340                 $gservers = DBA::select('gserver', ['id', 'url', 'nurl', 'network', 'poco', 'directory-type'],
2341                         ["NOT `blocked` AND NOT `failed` AND `directory-type` != ? AND `last_poco_query` < ?", GServer::DT_NONE, $last_update],
2342                         ['order' => ['RAND()']]);
2343
2344                 while ($gserver = DBA::fetch($gservers)) {
2345                         Logger::info('Update peer list', ['server' => $gserver['url'], 'id' => $gserver['id']]);
2346                         Worker::add(Worker::PRIORITY_LOW, 'UpdateServerPeers', $gserver['url']);
2347
2348                         Logger::info('Update directory', ['server' => $gserver['url'], 'id' => $gserver['id']]);
2349                         Worker::add(Worker::PRIORITY_LOW, 'UpdateServerDirectory', $gserver);
2350
2351                         $fields = ['last_poco_query' => DateTimeFormat::utcNow()];
2352                         self::update($fields, ['nurl' => $gserver['nurl']]);
2353
2354                         if (--$no_of_queries == 0) {
2355                                 break;
2356                         }
2357                 }
2358
2359                 DBA::close($gservers);
2360         }
2361
2362         /**
2363          * Discover federated servers
2364          */
2365         private static function discoverFederation()
2366         {
2367                 $last = DI::keyValue()->get('poco_last_federation_discovery');
2368
2369                 if ($last) {
2370                         $next = $last + (24 * 60 * 60);
2371
2372                         if ($next > time()) {
2373                                 return;
2374                         }
2375                 }
2376
2377                 // Discover federated servers
2378                 $protocols = ['activitypub', 'diaspora', 'dfrn', 'ostatus'];
2379                 foreach ($protocols as $protocol) {
2380                         $query = '{nodes(protocol:"' . $protocol . '"){host}}';
2381                         $curlResult = DI::httpClient()->fetch('https://the-federation.info/graphql?query=' . urlencode($query), HttpClientAccept::JSON);
2382                         if (!empty($curlResult)) {
2383                                 $data = json_decode($curlResult, true);
2384                                 if (!empty($data['data']['nodes'])) {
2385                                         foreach ($data['data']['nodes'] as $server) {
2386                                                 // Using "only_nodeinfo" since servers that are listed on that page should always have it.
2387                                                 self::add('https://' . $server['host'], true);
2388                                         }
2389                                 }
2390                         }
2391                 }
2392
2393                 // Disvover Mastodon servers
2394                 $accesstoken = DI::config()->get('system', 'instances_social_key');
2395
2396                 if (!empty($accesstoken)) {
2397                         $api = 'https://instances.social/api/1.0/instances/list?count=0';
2398                         $curlResult = DI::httpClient()->get($api, HttpClientAccept::JSON, [HttpClientOptions::HEADERS => ['Authorization' => ['Bearer ' . $accesstoken]]]);
2399                         if ($curlResult->isSuccess()) {
2400                                 $servers = json_decode($curlResult->getBody(), true);
2401
2402                                 if (!empty($servers['instances'])) {
2403                                         foreach ($servers['instances'] as $server) {
2404                                                 $url = (is_null($server['https_score']) ? 'http' : 'https') . '://' . $server['name'];
2405                                                 self::add($url);
2406                                         }
2407                                 }
2408                         }
2409                 }
2410
2411                 DI::keyValue()->set('poco_last_federation_discovery', time());
2412         }
2413
2414         /**
2415          * Set the protocol for the given server
2416          *
2417          * @param int $gsid     Server id
2418          * @param int $protocol Protocol id
2419          *
2420          * @throws Exception
2421          */
2422         public static function setProtocol(int $gsid, int $protocol)
2423         {
2424                 if (empty($gsid)) {
2425                         return;
2426                 }
2427
2428                 $gserver = DBA::selectFirst('gserver', ['protocol', 'url'], ['id' => $gsid]);
2429                 if (!DBA::isResult($gserver)) {
2430                         return;
2431                 }
2432
2433                 $old = $gserver['protocol'];
2434
2435                 if (!is_null($old)) {
2436                         /*
2437                         The priority for the protocols is:
2438                                 1. ActivityPub
2439                                 2. DFRN via Diaspora
2440                                 3. Legacy DFRN
2441                                 4. Diaspora
2442                                 5. OStatus
2443                         */
2444
2445                         // We don't need to change it when nothing is to be changed
2446                         if ($old == $protocol) {
2447                                 return;
2448                         }
2449
2450                         // We don't want to mark a server as OStatus when it had been marked with any other protocol before
2451                         if ($protocol == Post\DeliveryData::OSTATUS) {
2452                                 return;
2453                         }
2454
2455                         // If the server is marked as ActivityPub then we won't change it to anything different
2456                         if ($old == Post\DeliveryData::ACTIVITYPUB) {
2457                                 return;
2458                         }
2459
2460                         // Don't change it to anything lower than DFRN if the new one wasn't ActivityPub
2461                         if (($old == Post\DeliveryData::DFRN) && ($protocol != Post\DeliveryData::ACTIVITYPUB)) {
2462                                 return;
2463                         }
2464
2465                         // Don't change it to Diaspora when it is a legacy DFRN server
2466                         if (($old == Post\DeliveryData::LEGACY_DFRN) && ($protocol == Post\DeliveryData::DIASPORA)) {
2467                                 return;
2468                         }
2469                 }
2470
2471                 Logger::info('Protocol for server', ['protocol' => $protocol, 'old' => $old, 'id' => $gsid, 'url' => $gserver['url'], 'callstack' => System::callstack(20)]);
2472                 self::update(['protocol' => $protocol], ['id' => $gsid]);
2473         }
2474
2475         /**
2476          * Fetch the protocol of the given server
2477          *
2478          * @param int $gsid Server id
2479          *
2480          * @return ?int One of Post\DeliveryData protocol constants or null if unknown or gserver is missing
2481          *
2482          * @throws Exception
2483          */
2484         public static function getProtocol(int $gsid): ?int
2485         {
2486                 if (empty($gsid)) {
2487                         return null;
2488                 }
2489
2490                 $gserver = DBA::selectFirst('gserver', ['protocol'], ['id' => $gsid]);
2491                 if (DBA::isResult($gserver)) {
2492                         return $gserver['protocol'];
2493                 }
2494
2495                 return null;
2496         }
2497
2498         /**
2499          * Update rows in the gserver table.
2500          * Enforces gserver table field maximum sizes to avoid "Data too long" database errors
2501          *
2502          * @param array $fields
2503          * @param array $condition
2504          *
2505          * @return bool
2506          *
2507          * @throws Exception
2508          */
2509         public static function update(array $fields, array $condition): bool
2510         {
2511                 $fields = DI::dbaDefinition()->truncateFieldsForTable('gserver', $fields);
2512
2513                 return DBA::update('gserver', $fields, $condition);
2514         }
2515
2516         /**
2517          * Insert a row into the gserver table.
2518          * Enforces gserver table field maximum sizes to avoid "Data too long" database errors
2519          *
2520          * @param array $fields
2521          * @param int   $duplicate_mode What to do on a duplicated entry
2522          *
2523          * @return bool
2524          *
2525          * @throws Exception
2526          */
2527         public static function insert(array $fields, int $duplicate_mode = Database::INSERT_DEFAULT): bool
2528         {
2529                 $fields = DI::dbaDefinition()->truncateFieldsForTable('gserver', $fields);
2530
2531                 return DBA::insert('gserver', $fields, $duplicate_mode);
2532         }
2533 }