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\Core\Protocol;
  26 use Friendica\Database\DBA;
  27 use Friendica\DI;
  28 use Friendica\Protocol\ActivityPub;
  29 use Friendica\Util\DateTimeFormat;
  30 use Friendica\Util\Strings;
  31
  32 class ContactRelation
  33 {
  34         /**
  35          * No discovery of followers/followings
  36          */
  37         const DISCOVERY_NONE = 0;
  38         /**
  39          * Discover followers/followings of local contacts
  40          */
  41         const DISCOVERY_LOCAL = 1;
  42         /**
  43          * Discover followers/followings of local contacts and contacts that visibly interacted on the system
  44          */
  45         const DISCOVERY_INTERACTOR = 2;
  46         /**
  47          * Discover followers/followings of all contacts
  48          */
  49         const DISCOVERY_ALL = 3;
  50
  51         public static function store(int $target, int $actor, string $interaction_date)
  52         {
  53                 if ($actor == $target) {
  54                         return;
  55                 }
  56
  57                 DBA::update('contact-relation', ['last-interaction' => $interaction_date], ['cid' => $target, 'relation-cid' => $actor], true);
  58         }
  59
  60         /**
  61          * Fetches the followers of a given profile and adds them
  62          *
  63          * @param string $url URL of a profile
  64          * @return void
  65          */
  66         public static function discoverByUrl(string $url)
  67         {
  68                 $contact_discovery = DI::config()->get('system', 'contact_discovery');
  69
  70                 if ($contact_discovery == self::DISCOVERY_NONE) {
  71                         return;
  72                 }
  73
  74                 $contact = Contact::getByURL($url);
  75                 if (empty($contact)) {
  76                         return;
  77                 }
  78
  79                 if ($contact['last-discovery'] > DateTimeFormat::utc('now - 1 month')) {
  80                         Logger::info('No discovery - Last was less than a month ago.', ['id' => $contact['id'], 'url' => $url, 'discovery' => $contact['last-discovery']]);
  81                         return;
  82                 }
  83
  84                 if ($contact_discovery != self::DISCOVERY_ALL) {
  85                         $local = DBA::exists('contact', ["`nurl` = ? AND `uid` != ?", Strings::normaliseLink($url), 0]);
  86                         if (($contact_discovery == self::DISCOVERY_LOCAL) && !$local) {
  87                                 Logger::info('No discovery - This contact is not followed/following locally.', ['id' => $contact['id'], 'url' => $url]);
  88                                 return;
  89                         }
  90
  91                         if ($contact_discovery == self::DISCOVERY_INTERACTOR) {
  92                                 $interactor = DBA::exists('contact-relation', ["`relation-cid` = ? AND `last-interaction` > ?", $contact['id'], DBA::NULL_DATETIME]);
  93                                 if (!$local && !$interactor) {
  94                                         Logger::info('No discovery - This contact is not interacting locally.', ['id' => $contact['id'], 'url' => $url]);
  95                                         return;
  96                                 }
  97                         }
  98                 } elseif ($contact['created'] > DateTimeFormat::utc('now - 1 day')) {
  99                         // Newly created contacts are not discovered to avoid DDoS attacks
 100                         Logger::info('No discovery - Contact record is less than a day old.', ['id' => $contact['id'], 'url' => $url, 'discovery' => $contact['created']]);
 101                         return;
 102                 }
 103
 104                 if (in_array($contact['network'], [Protocol::ACTIVITYPUB, Protocol::DFRN, Protocol::OSTATUS])) {
 105                         // The contact is (most likely) speaking AP, so updating is allowed
 106                         $apcontact = APContact::getByURL($url);
 107                 } else {
 108                         // The contact isn't obviously speaking AP, so we don't allow updating
 109                         $apcontact = APContact::getByURL($url, false);
 110                 }
 111
 112                 if (!empty($apcontact['followers']) && is_string($apcontact['followers'])) {
 113                         $followers = ActivityPub::fetchItems($apcontact['followers']);
 114                 } else {
 115                         $followers = [];
 116                 }
 117
 118                 if (!empty($apcontact['following']) && is_string($apcontact['following'])) {
 119                         $followings = ActivityPub::fetchItems($apcontact['following']);
 120                 } else {
 121                         $followings = [];
 122                 }
 123
 124                 if (empty($followers) && empty($followings)) {
 125                         return;
 126                 }
 127
 128                 $target = $contact['id'];
 129
 130                 if (!empty($followers)) {
 131                         // Clear the follower list, since it will be recreated in the next step
 132                         DBA::update('contact-relation', ['follows' => false], ['cid' => $target]);
 133                 }
 134
 135                 $contacts = [];
 136                 foreach (array_merge($followers, $followings) as $contact) {
 137                         if (is_string($contact)) {
 138                                 $contacts[] = $contact;
 139                         } elseif (!empty($contact['url']) && is_string($contact['url'])) {
 140                                 $contacts[] = $contact['url'];
 141                         }
 142                 }
 143                 $contacts = array_unique($contacts);
 144
 145                 Logger::info('Discover contacts', ['id' => $target, 'url' => $url, 'contacts' => count($contacts)]);
 146                 foreach ($contacts as $contact) {
 147                         $actor = Contact::getIdForURL($contact);
 148                         if (!empty($actor)) {
 149                                 $fields = [];
 150                                 if (in_array($contact, $followers)) {
 151                                         $fields = ['cid' => $target, 'relation-cid' => $actor];
 152                                 } elseif (in_array($contact, $followings)) {
 153                                         $fields = ['cid' => $actor, 'relation-cid' => $target];
 154                                 } else {
 155                                         continue;
 156                                 }
 157
 158                                 DBA::update('contact-relation', ['follows' => true, 'follow-updated' => DateTimeFormat::utcNow()], $fields, true);
 159                         }
 160                 }
 161
 162                 if (!empty($followers)) {
 163                         // Delete all followers that aren't followers anymore (and aren't interacting)
 164                         DBA::delete('contact-relation', ['cid' => $target, 'follows' => false, 'last-interaction' => DBA::NULL_DATETIME]);
 165                 }
 166
 167                 DBA::update('contact', ['last-discovery' => DateTimeFormat::utcNow()], ['id' => $target]);
 168                 Logger::info('Contacts discovery finished, "last-discovery" set', ['id' => $target, 'url' => $url]);
 169                 return;
 170         }
 171 }