src/Model/ContactRelation.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;
  23
  24 use Friendica\Core\Logger;
  25 use Friendica\Database\DBA;
  26 use Friendica\DI;
  27 use Friendica\Protocol\ActivityPub;
  28 use Friendica\Util\DateTimeFormat;
  29 use Friendica\Util\Strings;
  30
  31 class ContactRelation
  32 {
  33         /**
  34          * No discovery of followers/followings
  35          */
  36         const DISCOVERY_NONE = 0;
  37         /**
  38          * Discover followers/followings of local contacts
  39          */
  40         const DISCOVERY_LOCAL = 1;
  41         /**
  42          * Discover followers/followings of local contacts and contacts that visibly interacted on the system
  43          */
  44         const DISCOVERY_INTERACTOR = 2;
  45         /**
  46          * Discover followers/followings of all contacts
  47          */
  48         const DISCOVERY_ALL = 3;
  49
  50         public static function store(int $target, int $actor, string $interaction_date)
  51         {
  52                 if ($actor == $target) {
  53                         return;
  54                 }
  55
  56                 DBA::update('contact-relation', ['last-interaction' => $interaction_date], ['cid' => $target, 'relation-cid' => $actor], true);
  57         }
  58
  59         /**
  60          * Fetches the followers of a given profile and adds them
  61          *
  62          * @param string $url URL of a profile
  63          * @return void
  64          */
  65         public static function discoverByUrl(string $url)
  66         {
  67                 $contact_discovery = DI::config()->get('system', 'contact_discovery');
  68
  69                 if ($contact_discovery == self::DISCOVERY_NONE) {
  70                         return;
  71                 }
  72
  73                 $contact = Contact::getByURL($url);
  74                 if (empty($contact)) {
  75                         return;
  76                 }
  77
  78                 if ($contact['last-discovery'] > DateTimeFormat::utc('now - 1 month')) {
  79                         Logger::info('No discovery - Last was less than a month ago.', ['id' => $contact['id'], 'url' => $url, 'discovery' => $contact['last-discovery']]);
  80                         return;
  81                 }
  82
  83                 if ($contact_discovery != self::DISCOVERY_ALL) {
  84                         $local = DBA::exists('contact', ["`nurl` = ? AND `uid` != ?", Strings::normaliseLink($url), 0]);
  85                         if (($contact_discovery == self::DISCOVERY_LOCAL) && !$local) {
  86                                 Logger::info('No discovery - This contact is not followed/following locally.', ['id' => $contact['id'], 'url' => $url]);
  87                                 return;
  88                         }
  89
  90                         if ($contact_discovery == self::DISCOVERY_INTERACTOR) {
  91                                 $interactor = DBA::exists('contact-relation', ["`relation-cid` = ? AND `last-interaction` > ?", $contact['id'], DBA::NULL_DATETIME]);
  92                                 if (!$local && !$interactor) {
  93                                         Logger::info('No discovery - This contact is not interacting locally.', ['id' => $contact['id'], 'url' => $url]);
  94                                         return;
  95                                 }
  96                         }
  97                 } elseif ($contact['created'] > DateTimeFormat::utc('now - 1 day')) {
  98                         // Newly created contacts are not discovered to avoid DDoS attacks
  99                         Logger::info('No discovery - Contact record is less than a day old.', ['id' => $contact['id'], 'url' => $url, 'discovery' => $contact['created']]);
 100                         return;
 101                 }
 102
 103                 $apcontact = APContact::getByURL($url);
 104
 105                 if (!empty($apcontact['followers']) && is_string($apcontact['followers'])) {
 106                         $followers = ActivityPub::fetchItems($apcontact['followers']);
 107                 } else {
 108                         $followers = [];
 109                 }
 110
 111                 if (!empty($apcontact['following']) && is_string($apcontact['following'])) {
 112                         $followings = ActivityPub::fetchItems($apcontact['following']);
 113                 } else {
 114                         $followings = [];
 115                 }
 116
 117                 if (empty($followers) && empty($followings)) {
 118                         return;
 119                 }
 120
 121                 $target = $contact['id'];
 122
 123                 if (!empty($followers)) {
 124                         // Clear the follower list, since it will be recreated in the next step
 125                         DBA::update('contact-relation', ['follows' => false], ['cid' => $target]);
 126                 }
 127
 128                 $contacts = [];
 129                 foreach (array_merge($followers, $followings) as $contact) {
 130                         if (is_string($contact)) {
 131                                 $contacts[] = $contact;
 132                         } elseif (!empty($contact['url']) && is_string($contact['url'])) {
 133                                 $contacts[] = $contact['url'];
 134                         }
 135                 }
 136                 $contacts = array_unique($contacts);
 137
 138                 Logger::info('Discover contacts', ['id' => $target, 'url' => $url, 'contacts' => count($contacts)]);
 139                 foreach ($contacts as $contact) {
 140                         $actor = Contact::getIdForURL($contact);
 141                         if (!empty($actor)) {
 142                                 $fields = [];
 143                                 if (in_array($contact, $followers)) {
 144                                         $fields = ['cid' => $target, 'relation-cid' => $actor];
 145                                 } elseif (in_array($contact, $followings)) {
 146                                         $fields = ['cid' => $actor, 'relation-cid' => $target];
 147                                 } else {
 148                                         continue;
 149                                 }
 150
 151                                 DBA::update('contact-relation', ['follows' => true, 'follow-updated' => DateTimeFormat::utcNow()], $fields, true);
 152                         }
 153                 }
 154
 155                 if (!empty($followers)) {
 156                         // Delete all followers that aren't followers anymore (and aren't interacting)
 157                         DBA::delete('contact-relation', ['cid' => $target, 'follows' => false, 'last-interaction' => DBA::NULL_DATETIME]);
 158                 }
 159
 160                 DBA::update('contact', ['last-discovery' => DateTimeFormat::utcNow()], ['id' => $target]);
 161                 Logger::info('Contacts discovery finished, "last-discovery" set', ['id' => $target, 'url' => $url]);
 162                 return;
 163         }
 164 }