src/Model/Contact/Relation.php

   1 <?php
   2 /**
   3  * @copyright Copyright (C) 2020, Friendica
   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\Contact;
  23
  24 use Exception;
  25 use Friendica\Core\Logger;
  26 use Friendica\Core\Protocol;
  27 use Friendica\Database\DBA;
  28 use Friendica\DI;
  29 use Friendica\Protocol\ActivityPub;
  30 use Friendica\Util\DateTimeFormat;
  31 use Friendica\Util\Strings;
  32
  33 /**
  34  * This class provides relationship information based on the `contact-relation` table.
  35  * This table is directional (cid = source, relation-cid = target), references public contacts (with uid=0) and records both
  36  * follows and the last interaction (likes/comments) on public posts.
  37  */
  38 class Relation
  39 {
  40         /**
  41          * No discovery of followers/followings
  42          */
  43         const DISCOVERY_NONE = 0;
  44         /**
  45          * Discover followers/followings of local contacts
  46          */
  47         const DISCOVERY_LOCAL = 1;
  48         /**
  49          * Discover followers/followings of local contacts and contacts that visibly interacted on the system
  50          */
  51         const DISCOVERY_INTERACTOR = 2;
  52         /**
  53          * Discover followers/followings of all contacts
  54          */
  55         const DISCOVERY_ALL = 3;
  56
  57         public static function store(int $target, int $actor, string $interaction_date)
  58         {
  59                 if ($actor == $target) {
  60                         return;
  61                 }
  62
  63                 DBA::update('contact-relation', ['last-interaction' => $interaction_date], ['cid' => $target, 'relation-cid' => $actor], true);
  64         }
  65
  66         /**
  67          * Fetches the followers of a given profile and adds them
  68          *
  69          * @param string $url URL of a profile
  70          * @return void
  71          */
  72         public static function discoverByUrl(string $url)
  73         {
  74                 $contact = Contact::getByURL($url);
  75                 if (empty($contact)) {
  76                         return;
  77                 }
  78
  79                 if (!self::isDiscoverable($url, $contact)) {
  80                         return;
  81                 }
  82
  83                 $apcontact = APContact::getByURL($url, false);
  84
  85                 if (!empty($apcontact['followers']) && is_string($apcontact['followers'])) {
  86                         $followers = ActivityPub::fetchItems($apcontact['followers']);
  87                 } else {
  88                         $followers = [];
  89                 }
  90
  91                 if (!empty($apcontact['following']) && is_string($apcontact['following'])) {
  92                         $followings = ActivityPub::fetchItems($apcontact['following']);
  93                 } else {
  94                         $followings = [];
  95                 }
  96
  97                 if (empty($followers) && empty($followings)) {
  98                         DBA::update('contact', ['last-discovery' => DateTimeFormat::utcNow()], ['id' => $contact['id']]);
  99                         Logger::info('The contact does not offer discoverable data', ['id' => $contact['id'], 'url' => $url, 'network' => $contact['network']]);
 100                         return;
 101                 }
 102
 103                 $target = $contact['id'];
 104
 105                 if (!empty($followers)) {
 106                         // Clear the follower list, since it will be recreated in the next step
 107                         DBA::update('contact-relation', ['follows' => false], ['cid' => $target]);
 108                 }
 109
 110                 $contacts = [];
 111                 foreach (array_merge($followers, $followings) as $contact) {
 112                         if (is_string($contact)) {
 113                                 $contacts[] = $contact;
 114                         } elseif (!empty($contact['url']) && is_string($contact['url'])) {
 115                                 $contacts[] = $contact['url'];
 116                         }
 117                 }
 118                 $contacts = array_unique($contacts);
 119
 120                 $follower_counter = 0;
 121                 $following_counter = 0;
 122
 123                 Logger::info('Discover contacts', ['id' => $target, 'url' => $url, 'contacts' => count($contacts)]);
 124                 foreach ($contacts as $contact) {
 125                         $actor = Contact::getIdForURL($contact);
 126                         if (!empty($actor)) {
 127                                 if (in_array($contact, $followers)) {
 128                                         $fields = ['cid' => $target, 'relation-cid' => $actor];
 129                                         DBA::update('contact-relation', ['follows' => true, 'follow-updated' => DateTimeFormat::utcNow()], $fields, true);
 130                                         $follower_counter++;
 131                                 }
 132
 133                                 if (in_array($contact, $followings)) {
 134                                         $fields = ['cid' => $actor, 'relation-cid' => $target];
 135                                         DBA::update('contact-relation', ['follows' => true, 'follow-updated' => DateTimeFormat::utcNow()], $fields, true);
 136                                         $following_counter++;
 137                                 }
 138                         }
 139                 }
 140
 141                 if (!empty($followers)) {
 142                         // Delete all followers that aren't followers anymore (and aren't interacting)
 143                         DBA::delete('contact-relation', ['cid' => $target, 'follows' => false, 'last-interaction' => DBA::NULL_DATETIME]);
 144                 }
 145
 146                 DBA::update('contact', ['last-discovery' => DateTimeFormat::utcNow()], ['id' => $target]);
 147                 Logger::info('Contacts discovery finished', ['id' => $target, 'url' => $url, 'follower' => $follower_counter, 'following' => $following_counter]);
 148                 return;
 149         }
 150
 151         /**
 152          * Tests if a given contact url is discoverable
 153          *
 154          * @param string $url     Contact url
 155          * @param array  $contact Contact array
 156          * @return boolean True if contact is discoverable
 157          */
 158         public static function isDiscoverable(string $url, array $contact = [])
 159         {
 160                 $contact_discovery = DI::config()->get('system', 'contact_discovery');
 161
 162                 if ($contact_discovery == self::DISCOVERY_NONE) {
 163                         return false;
 164                 }
 165
 166                 if (empty($contact)) {
 167                         $contact = Contact::getByURL($url);
 168                 }
 169
 170                 if (empty($contact)) {
 171                         return false;
 172                 }
 173
 174                 if ($contact['last-discovery'] > DateTimeFormat::utc('now - 1 month')) {
 175                         Logger::info('No discovery - Last was less than a month ago.', ['id' => $contact['id'], 'url' => $url, 'discovery' => $contact['last-discovery']]);
 176                         return false;
 177                 }
 178
 179                 if ($contact_discovery != self::DISCOVERY_ALL) {
 180                         $local = DBA::exists('contact', ["`nurl` = ? AND `uid` != ?", Strings::normaliseLink($url), 0]);
 181                         if (($contact_discovery == self::DISCOVERY_LOCAL) && !$local) {
 182                                 Logger::info('No discovery - This contact is not followed/following locally.', ['id' => $contact['id'], 'url' => $url]);
 183                                 return false;
 184                         }
 185
 186                         if ($contact_discovery == self::DISCOVERY_INTERACTOR) {
 187                                 $interactor = DBA::exists('contact-relation', ["`relation-cid` = ? AND `last-interaction` > ?", $contact['id'], DBA::NULL_DATETIME]);
 188                                 if (!$local && !$interactor) {
 189                                         Logger::info('No discovery - This contact is not interacting locally.', ['id' => $contact['id'], 'url' => $url]);
 190                                         return false;
 191                                 }
 192                         }
 193                 } elseif ($contact['created'] > DateTimeFormat::utc('now - 1 day')) {
 194                         // Newly created contacts are not discovered to avoid DDoS attacks
 195                         Logger::info('No discovery - Contact record is less than a day old.', ['id' => $contact['id'], 'url' => $url, 'discovery' => $contact['created']]);
 196                         return false;
 197                 }
 198
 199                 if (!in_array($contact['network'], [Protocol::ACTIVITYPUB, Protocol::DFRN, Protocol::OSTATUS])) {
 200                         $apcontact = APContact::getByURL($url, false);
 201                         if (empty($apcontact)) {
 202                                 Logger::info('No discovery - The contact does not seem to speak ActivityPub.', ['id' => $contact['id'], 'url' => $url, 'network' => $contact['network']]);
 203                                 return false;
 204                         }
 205                 }
 206
 207                 return true;
 208         }
 209
 210         /**
 211          * Counts all the known follows of the provided public contact
 212          *
 213          * @param int   $cid       Public contact id
 214          * @param array $condition Additional condition on the contact table
 215          * @return int
 216          * @throws Exception
 217          */
 218         public static function countFollows(int $cid, array $condition = [])
 219         {
 220                 $condition = DBA::mergeConditions($condition,
 221                         ['`id` IN (
 222     SELECT `relation-cid`
 223     FROM `contact-relation`
 224     WHERE `cid` = ?
 225     AND `follows`
 226 )', $cid]
 227                 );
 228
 229                 return DI::dba()->count('contact', $condition);
 230         }
 231
 232         /**
 233          * Returns a paginated list of contacts that are followed the provided public contact.
 234          *
 235          * @param int   $cid       Public contact id
 236          * @param array $condition Additional condition on the contact table
 237          * @param int   $count
 238          * @param int   $offset
 239          * @param bool  $shuffle
 240          * @return array
 241          * @throws Exception
 242          */
 243         public static function listFollows(int $cid, array $condition = [], int $count = 30, int $offset = 0, bool $shuffle = false)
 244         {
 245                 $condition = DBA::mergeConditions($condition,
 246                         ['`id` IN (
 247     SELECT `relation-cid`
 248     FROM `contact-relation`
 249     WHERE `cid` = ?
 250     AND `follows`
 251 )', $cid]
 252                 );
 253
 254                 $follows = DI::dba()->selectToArray(
 255                         'contact',
 256                         $condition,
 257                         [
 258                                 'limit' => [$offset, $count],
 259                                 'order' => [$shuffle ? 'RAND()' : 'name']
 260                         ]
 261                 );
 262
 263                 return $follows;
 264         }
 265
 266         /**
 267          * Counts all the known followers of the provided public contact
 268          *
 269          * @param int   $cid       Public contact id
 270          * @param array $condition Additional condition on the contact table
 271          * @return int
 272          * @throws Exception
 273          */
 274         public static function countFollowers(int $cid, array $condition = [])
 275         {
 276                 $condition = DBA::mergeConditions($condition,
 277                         ['`id` IN (
 278     SELECT `cid`
 279     FROM `contact-relation`
 280     WHERE `relation-cid` = ?
 281     AND `follows`
 282 )', $cid]
 283                 );
 284
 285                 return DI::dba()->count('contact', $condition);
 286         }
 287
 288         /**
 289          * Returns a paginated list of contacts that follow the provided public contact.
 290          *
 291          * @param int   $cid       Public contact id
 292          * @param array $condition Additional condition on the contact table
 293          * @param int   $count
 294          * @param int   $offset
 295          * @param bool  $shuffle
 296          * @return array
 297          * @throws Exception
 298          */
 299         public static function listFollowers(int $cid, array $condition = [], int $count = 30, int $offset = 0, bool $shuffle = false)
 300         {
 301                 $condition = DBA::mergeConditions($condition,
 302                         ['`id` IN (
 303     SELECT `cid`
 304     FROM `contact-relation`
 305     WHERE `relation-cid` = ?
 306     AND `follows`
 307 )', $cid]
 308                 );
 309
 310                 $followers = DI::dba()->selectToArray(
 311                         'contact',
 312                         $condition,
 313                         [
 314                                 'limit' => [$offset, $count],
 315                                 'order' => [$shuffle ? 'RAND()' : 'name']
 316                         ]
 317                 );
 318
 319                 return $followers;
 320         }
 321
 322         /**
 323          * Counts the number of contacts that both provided public contacts have interacted with at least once.
 324          * Interactions include follows and likes and comments on public posts.
 325          *
 326          * @param int   $sourceId  Public contact id
 327          * @param int   $targetId  Public contact id
 328          * @param array $condition Additional condition array on the contact table
 329          * @return int
 330          * @throws Exception
 331          */
 332         public static function countCommon(int $sourceId, int $targetId, array $condition = [])
 333         {
 334                 $condition = DBA::mergeConditions($condition,
 335                         ['`id` IN (
 336     SELECT `relation-cid`
 337     FROM `contact-relation`
 338     WHERE `cid` = ?
 339 )
 340   AND `id` IN (
 341     SELECT `relation-cid`
 342     FROM `contact-relation`
 343     WHERE `cid` = ?
 344 )', $sourceId, $targetId]
 345                 );
 346
 347                 $total = DI::dba()->count('contact', $condition);
 348
 349                 return $total;
 350         }
 351
 352         /**
 353          * Returns a paginated list of contacts that both provided public contacts have interacted with at least once.
 354          * Interactions include follows and likes and comments on public posts.
 355          *
 356          * @param int   $sourceId  Public contact id
 357          * @param int   $targetId  Public contact id
 358          * @param array $condition Additional condition on the contact table
 359          * @param int   $count
 360          * @param int   $offset
 361          * @param bool  $shuffle
 362          * @return array
 363          * @throws Exception
 364          */
 365         public static function listCommon(int $sourceId, int $targetId, array $condition = [], int $count = 30, int $offset = 0, bool $shuffle = false)
 366         {
 367                 $condition = DBA::mergeConditions($condition,
 368                         ["`id` IN (
 369     SELECT `relation-cid`
 370     FROM `contact-relation`
 371     WHERE `cid` = ?
 372       AND `follows`
 373 )
 374   AND `id` IN (
 375     SELECT `relation-cid`
 376     FROM `contact-relation`
 377     WHERE `cid` = ?
 378       AND `follows`
 379 )", $sourceId, $targetId]
 380                 );
 381
 382                 $contacts = DI::dba()->selectToArray(
 383                         'contact',
 384                         $condition,
 385                         [
 386                                 'limit' => [$offset, $count],
 387                                 'order' => [$shuffle ? 'name' : 'RAND()'],
 388                         ]
 389                 );
 390
 391                 return $contacts;
 392         }
 393
 394
 395         /**
 396          * Counts the number of contacts that are followed by both provided public contacts.
 397          *
 398          * @param int   $sourceId  Public contact id
 399          * @param int   $targetId  Public contact id
 400          * @param array $condition Additional condition array on the contact table
 401          * @return int
 402          * @throws Exception
 403          */
 404         public static function countCommonFollows(int $sourceId, int $targetId, array $condition = [])
 405         {
 406                 $condition = DBA::mergeConditions($condition,
 407                         ['`id` IN (
 408     SELECT `relation-cid`
 409     FROM `contact-relation`
 410     WHERE `cid` = ?
 411       AND `follows`
 412 )
 413   AND `id` IN (
 414     SELECT `relation-cid`
 415     FROM `contact-relation`
 416     WHERE `cid` = ?
 417       AND `follows`
 418 )', $sourceId, $targetId]
 419                 );
 420
 421                 $total = DI::dba()->count('contact', $condition);
 422
 423                 return $total;
 424         }
 425
 426         /**
 427          * Returns a paginated list of contacts that are followed by both provided public contacts.
 428          *
 429          * @param int   $sourceId  Public contact id
 430          * @param int   $targetId  Public contact id
 431          * @param array $condition Additional condition array on the contact table
 432          * @param int   $count
 433          * @param int   $offset
 434          * @param bool  $shuffle
 435          * @return array
 436          * @throws Exception
 437          */
 438         public static function listCommonFollows(int $sourceId, int $targetId, array $condition = [], int $count = 30, int $offset = 0, bool $shuffle = false)
 439         {
 440                 $condition = DBA::mergeConditions($condition,
 441                         ["`id` IN (
 442     SELECT `relation-cid`
 443     FROM `contact-relation`
 444     WHERE `cid` = ?
 445       AND `follows`
 446 )
 447   AND `id` IN (
 448     SELECT `relation-cid`
 449     FROM `contact-relation`
 450     WHERE `cid` = ?
 451       AND `follows`
 452 )", $sourceId, $targetId]
 453                 );
 454
 455                 $contacts = DI::dba()->selectToArray(
 456                         'contact',
 457                         $condition,
 458                         [
 459                                 'limit' => [$offset, $count],
 460                                 'order' => [$shuffle ? 'name' : 'RAND()'],
 461                         ]
 462                 );
 463
 464                 return $contacts;
 465         }
 466
 467         /**
 468          * Counts the number of contacts that follow both provided public contacts.
 469          *
 470          * @param int   $sourceId  Public contact id
 471          * @param int   $targetId  Public contact id
 472          * @param array $condition Additional condition on the contact table
 473          * @return int
 474          * @throws Exception
 475          */
 476         public static function countCommonFollowers(int $sourceId, int $targetId, array $condition = [])
 477         {
 478                 $condition = DBA::mergeConditions($condition,
 479                         ['`id` IN (
 480     SELECT `cid`
 481     FROM `contact-relation`
 482     WHERE `relation-cid` = ?
 483       AND `follows`
 484 )
 485   AND `id` IN (
 486     SELECT `cid`
 487     FROM `contact-relation`
 488     WHERE `relation-cid` = ?
 489       AND `follows`
 490 )', $sourceId, $targetId]
 491                 );
 492
 493                 $total = DI::dba()->count('contact', $condition);
 494
 495                 return $total;
 496         }
 497
 498         /**
 499          * Returns a paginated list of contacts that follow both provided public contacts.
 500          *
 501          * @param int   $sourceId  Public contact id
 502          * @param int   $targetId  Public contact id
 503          * @param array $condition Additional condition on the contact table
 504          * @param int   $count
 505          * @param int   $offset
 506          * @param bool  $shuffle
 507          * @return array
 508          * @throws Exception
 509          */
 510         public static function listCommonFollowers(int $sourceId, int $targetId, array $condition = [], int $count = 30, int $offset = 0, bool $shuffle = false)
 511         {
 512                 $condition = DBA::mergeConditions($condition,
 513                         ["`id` IN (
 514     SELECT `cid`
 515     FROM `contact-relation`
 516     WHERE `relation-cid` = ?
 517       AND `follows`
 518 )
 519   AND `id` IN (
 520     SELECT `cid`
 521     FROM `contact-relation`
 522     WHERE `relation-cid` = ?
 523       AND `follows`
 524 )", $sourceId, $targetId]
 525                 );
 526
 527                 $contacts = DI::dba()->selectToArray(
 528                         'contact',
 529                         $condition,
 530                         [
 531                                 'limit' => [$offset, $count],
 532                                 'order' => [$shuffle ? 'name' : 'RAND()'],
 533                         ]
 534                 );
 535
 536                 return $contacts;
 537         }
 538 }