includes/WatchedItemStore.php

   1 <?php
   2
   3 use Liuggio\StatsdClient\Factory\StatsdDataFactoryInterface;
   4 use MediaWiki\MediaWikiServices;
   5 use MediaWiki\Linker\LinkTarget;
   6 use Wikimedia\Assert\Assert;
   7
   8 /**
   9  * Storage layer class for WatchedItems.
  10  * Database interaction.
  11  *
  12  * @author Addshore
  13  *
  14  * @since 1.27
  15  */
  16 class WatchedItemStore implements StatsdAwareInterface {
  17
  18         const SORT_DESC = 'DESC';
  19         const SORT_ASC = 'ASC';
  20
  21         /**
  22          * @var LoadBalancer
  23          */
  24         private $loadBalancer;
  25
  26         /**
  27          * @var HashBagOStuff
  28          */
  29         private $cache;
  30
  31         /**
  32          * @var array[] Looks like $cacheIndex[Namespace ID][Target DB Key][User Id] => 'key'
  33          * The index is needed so that on mass changes all relevant items can be un-cached.
  34          * For example: Clearing a users watchlist of all items or updating notification timestamps
  35          *              for all users watching a single target.
  36          */
  37         private $cacheIndex = [];
  38
  39         /**
  40          * @var callable|null
  41          */
  42         private $deferredUpdatesAddCallableUpdateCallback;
  43
  44         /**
  45          * @var callable|null
  46          */
  47         private $revisionGetTimestampFromIdCallback;
  48
  49         /**
  50          * @var StatsdDataFactoryInterface
  51          */
  52         private $stats;
  53
  54         /**
  55          * @param LoadBalancer $loadBalancer
  56          * @param HashBagOStuff $cache
  57          */
  58         public function __construct(
  59                 LoadBalancer $loadBalancer,
  60                 HashBagOStuff $cache
  61         ) {
  62                 $this->loadBalancer = $loadBalancer;
  63                 $this->cache = $cache;
  64                 $this->stats = new NullStatsdDataFactory();
  65                 $this->deferredUpdatesAddCallableUpdateCallback = [ 'DeferredUpdates', 'addCallableUpdate' ];
  66                 $this->revisionGetTimestampFromIdCallback = [ 'Revision', 'getTimestampFromId' ];
  67         }
  68
  69         public function setStatsdDataFactory( StatsdDataFactoryInterface $stats ) {
  70                 $this->stats = $stats;
  71         }
  72
  73         /**
  74          * Overrides the DeferredUpdates::addCallableUpdate callback
  75          * This is intended for use while testing and will fail if MW_PHPUNIT_TEST is not defined.
  76          *
  77          * @param callable $callback
  78          *
  79          * @see DeferredUpdates::addCallableUpdate for callback signiture
  80          *
  81          * @return ScopedCallback to reset the overridden value
  82          * @throws MWException
  83          */
  84         public function overrideDeferredUpdatesAddCallableUpdateCallback( $callback ) {
  85                 if ( !defined( 'MW_PHPUNIT_TEST' ) ) {
  86                         throw new MWException(
  87                                 'Cannot override DeferredUpdates::addCallableUpdate callback in operation.'
  88                         );
  89                 }
  90                 Assert::parameterType( 'callable', $callback, '$callback' );
  91
  92                 $previousValue = $this->deferredUpdatesAddCallableUpdateCallback;
  93                 $this->deferredUpdatesAddCallableUpdateCallback = $callback;
  94                 return new ScopedCallback( function() use ( $previousValue ) {
  95                         $this->deferredUpdatesAddCallableUpdateCallback = $previousValue;
  96                 } );
  97         }
  98
  99         /**
 100          * Overrides the Revision::getTimestampFromId callback
 101          * This is intended for use while testing and will fail if MW_PHPUNIT_TEST is not defined.
 102          *
 103          * @param callable $callback
 104          * @see Revision::getTimestampFromId for callback signiture
 105          *
 106          * @return ScopedCallback to reset the overridden value
 107          * @throws MWException
 108          */
 109         public function overrideRevisionGetTimestampFromIdCallback( $callback ) {
 110                 if ( !defined( 'MW_PHPUNIT_TEST' ) ) {
 111                         throw new MWException(
 112                                 'Cannot override Revision::getTimestampFromId callback in operation.'
 113                         );
 114                 }
 115                 Assert::parameterType( 'callable', $callback, '$callback' );
 116
 117                 $previousValue = $this->revisionGetTimestampFromIdCallback;
 118                 $this->revisionGetTimestampFromIdCallback = $callback;
 119                 return new ScopedCallback( function() use ( $previousValue ) {
 120                         $this->revisionGetTimestampFromIdCallback = $previousValue;
 121                 } );
 122         }
 123
 124         private function getCacheKey( User $user, LinkTarget $target ) {
 125                 return $this->cache->makeKey(
 126                         (string)$target->getNamespace(),
 127                         $target->getDBkey(),
 128                         (string)$user->getId()
 129                 );
 130         }
 131
 132         private function cache( WatchedItem $item ) {
 133                 $user = $item->getUser();
 134                 $target = $item->getLinkTarget();
 135                 $key = $this->getCacheKey( $user, $target );
 136                 $this->cache->set( $key, $item );
 137                 $this->cacheIndex[$target->getNamespace()][$target->getDBkey()][$user->getId()] = $key;
 138                 $this->stats->increment( 'WatchedItemStore.cache' );
 139         }
 140
 141         private function uncache( User $user, LinkTarget $target ) {
 142                 $this->cache->delete( $this->getCacheKey( $user, $target ) );
 143                 unset( $this->cacheIndex[$target->getNamespace()][$target->getDBkey()][$user->getId()] );
 144                 $this->stats->increment( 'WatchedItemStore.uncache' );
 145         }
 146
 147         private function uncacheLinkTarget( LinkTarget $target ) {
 148                 $this->stats->increment( 'WatchedItemStore.uncacheLinkTarget' );
 149                 if ( !isset( $this->cacheIndex[$target->getNamespace()][$target->getDBkey()] ) ) {
 150                         return;
 151                 }
 152                 foreach ( $this->cacheIndex[$target->getNamespace()][$target->getDBkey()] as $key ) {
 153                         $this->stats->increment( 'WatchedItemStore.uncacheLinkTarget.items' );
 154                         $this->cache->delete( $key );
 155                 }
 156         }
 157
 158         private function uncacheUser( User $user ) {
 159                 $this->stats->increment( 'WatchedItemStore.uncacheUser' );
 160                 foreach ( $this->cacheIndex as $ns => $dbKeyArray ) {
 161                         foreach ( $dbKeyArray as $dbKey => $userArray ) {
 162                                 if ( isset( $userArray[$user->getId()] ) ) {
 163                                         $this->stats->increment( 'WatchedItemStore.uncacheUser.items' );
 164                                         $this->cache->delete( $userArray[$user->getId()] );
 165                                 }
 166                         }
 167                 }
 168         }
 169
 170         /**
 171          * @param User $user
 172          * @param LinkTarget $target
 173          *
 174          * @return WatchedItem|null
 175          */
 176         private function getCached( User $user, LinkTarget $target ) {
 177                 return $this->cache->get( $this->getCacheKey( $user, $target ) );
 178         }
 179
 180         /**
 181          * Return an array of conditions to select or update the appropriate database
 182          * row.
 183          *
 184          * @param User $user
 185          * @param LinkTarget $target
 186          *
 187          * @return array
 188          */
 189         private function dbCond( User $user, LinkTarget $target ) {
 190                 return [
 191                         'wl_user' => $user->getId(),
 192                         'wl_namespace' => $target->getNamespace(),
 193                         'wl_title' => $target->getDBkey(),
 194                 ];
 195         }
 196
 197         /**
 198          * @param int $slaveOrMaster DB_MASTER or DB_SLAVE
 199          *
 200          * @return DatabaseBase
 201          * @throws MWException
 202          */
 203         private function getConnection( $slaveOrMaster ) {
 204                 return $this->loadBalancer->getConnection( $slaveOrMaster, [ 'watchlist' ] );
 205         }
 206
 207         /**
 208          * @param DatabaseBase $connection
 209          *
 210          * @throws MWException
 211          */
 212         private function reuseConnection( $connection ) {
 213                 $this->loadBalancer->reuseConnection( $connection );
 214         }
 215
 216         /**
 217          * Count the number of individual items that are watched by the user.
 218          * If a subject and corresponding talk page are watched this will return 2.
 219          *
 220          * @param User $user
 221          *
 222          * @return int
 223          */
 224         public function countWatchedItems( User $user ) {
 225                 $dbr = $this->getConnection( DB_SLAVE );
 226                 $return = (int)$dbr->selectField(
 227                         'watchlist',
 228                         'COUNT(*)',
 229                         [
 230                                 'wl_user' => $user->getId()
 231                         ],
 232                         __METHOD__
 233                 );
 234                 $this->reuseConnection( $dbr );
 235
 236                 return $return;
 237         }
 238
 239         /**
 240          * @param LinkTarget $target
 241          *
 242          * @return int
 243          */
 244         public function countWatchers( LinkTarget $target ) {
 245                 $dbr = $this->getConnection( DB_SLAVE );
 246                 $return = (int)$dbr->selectField(
 247                         'watchlist',
 248                         'COUNT(*)',
 249                         [
 250                                 'wl_namespace' => $target->getNamespace(),
 251                                 'wl_title' => $target->getDBkey(),
 252                         ],
 253                         __METHOD__
 254                 );
 255                 $this->reuseConnection( $dbr );
 256
 257                 return $return;
 258         }
 259
 260         /**
 261          * Number of page watchers who also visited a "recent" edit
 262          *
 263          * @param LinkTarget $target
 264          * @param mixed $threshold timestamp accepted by wfTimestamp
 265          *
 266          * @return int
 267          * @throws DBUnexpectedError
 268          * @throws MWException
 269          */
 270         public function countVisitingWatchers( LinkTarget $target, $threshold ) {
 271                 $dbr = $this->getConnection( DB_SLAVE );
 272                 $visitingWatchers = (int)$dbr->selectField(
 273                         'watchlist',
 274                         'COUNT(*)',
 275                         [
 276                                 'wl_namespace' => $target->getNamespace(),
 277                                 'wl_title' => $target->getDBkey(),
 278                                 'wl_notificationtimestamp >= ' .
 279                                 $dbr->addQuotes( $dbr->timestamp( $threshold ) ) .
 280                                 ' OR wl_notificationtimestamp IS NULL'
 281                         ],
 282                         __METHOD__
 283                 );
 284                 $this->reuseConnection( $dbr );
 285
 286                 return $visitingWatchers;
 287         }
 288
 289         /**
 290          * @param LinkTarget[] $targets
 291          * @param array $options Allowed keys:
 292          *        'minimumWatchers' => int
 293          *
 294          * @return array multi dimensional like $return[$namespaceId][$titleString] = int $watchers
 295          *         All targets will be present in the result. 0 either means no watchers or the number
 296          *         of watchers was below the minimumWatchers option if passed.
 297          */
 298         public function countWatchersMultiple( array $targets, array $options = [] ) {
 299                 $dbOptions = [ 'GROUP BY' => [ 'wl_namespace', 'wl_title' ] ];
 300
 301                 $dbr = $this->getConnection( DB_SLAVE );
 302
 303                 if ( array_key_exists( 'minimumWatchers', $options ) ) {
 304                         $dbOptions['HAVING'] = 'COUNT(*) >= ' . (int)$options['minimumWatchers'];
 305                 }
 306
 307                 $lb = new LinkBatch( $targets );
 308                 $res = $dbr->select(
 309                         'watchlist',
 310                         [ 'wl_title', 'wl_namespace', 'watchers' => 'COUNT(*)' ],
 311                         [ $lb->constructSet( 'wl', $dbr ) ],
 312                         __METHOD__,
 313                         $dbOptions
 314                 );
 315
 316                 $this->reuseConnection( $dbr );
 317
 318                 $watchCounts = [];
 319                 foreach ( $targets as $linkTarget ) {
 320                         $watchCounts[$linkTarget->getNamespace()][$linkTarget->getDBkey()] = 0;
 321                 }
 322
 323                 foreach ( $res as $row ) {
 324                         $watchCounts[$row->wl_namespace][$row->wl_title] = (int)$row->watchers;
 325                 }
 326
 327                 return $watchCounts;
 328         }
 329
 330         /**
 331          * Number of watchers of each page who have visited recent edits to that page
 332          *
 333          * @param array $targetsWithVisitThresholds array of pairs (LinkTarget $target, mixed $threshold),
 334          *        $threshold is:
 335          *        - a timestamp of the recent edit if $target exists (format accepted by wfTimestamp)
 336          *        - null if $target doesn't exist
 337          * @param int|null $minimumWatchers
 338          * @return array multi-dimensional like $return[$namespaceId][$titleString] = $watchers,
 339          *         where $watchers is an int:
 340          *         - if the page exists, number of users watching who have visited the page recently
 341          *         - if the page doesn't exist, number of users that have the page on their watchlist
 342          *         - 0 means there are no visiting watchers or their number is below the minimumWatchers
 343          *         option (if passed).
 344          */
 345         public function countVisitingWatchersMultiple(
 346                 array $targetsWithVisitThresholds,
 347                 $minimumWatchers = null
 348         ) {
 349                 $dbr = $this->getConnection( DB_SLAVE );
 350
 351                 $conds = $this->getVisitingWatchersCondition( $dbr, $targetsWithVisitThresholds );
 352
 353                 $dbOptions = [ 'GROUP BY' => [ 'wl_namespace', 'wl_title' ] ];
 354                 if ( $minimumWatchers !== null ) {
 355                         $dbOptions['HAVING'] = 'COUNT(*) >= ' . (int)$minimumWatchers;
 356                 }
 357                 $res = $dbr->select(
 358                         'watchlist',
 359                         [ 'wl_namespace', 'wl_title', 'watchers' => 'COUNT(*)' ],
 360                         $conds,
 361                         __METHOD__,
 362                         $dbOptions
 363                 );
 364
 365                 $this->reuseConnection( $dbr );
 366
 367                 $watcherCounts = [];
 368                 foreach ( $targetsWithVisitThresholds as list( $target ) ) {
 369                         /* @var LinkTarget $target */
 370                         $watcherCounts[$target->getNamespace()][$target->getDBkey()] = 0;
 371                 }
 372
 373                 foreach ( $res as $row ) {
 374                         $watcherCounts[$row->wl_namespace][$row->wl_title] = (int)$row->watchers;
 375                 }
 376
 377                 return $watcherCounts;
 378         }
 379
 380         /**
 381          * Generates condition for the query used in a batch count visiting watchers.
 382          *
 383          * @param IDatabase $db
 384          * @param array $targetsWithVisitThresholds array of pairs (LinkTarget, last visit threshold)
 385          * @return string
 386          */
 387         private function getVisitingWatchersCondition(
 388                 IDatabase $db,
 389                 array $targetsWithVisitThresholds
 390         ) {
 391                 $missingTargets = [];
 392                 $namespaceConds = [];
 393                 foreach ( $targetsWithVisitThresholds as list( $target, $threshold ) ) {
 394                         if ( $threshold === null ) {
 395                                 $missingTargets[] = $target;
 396                                 continue;
 397                         }
 398                         /* @var LinkTarget $target */
 399                         $namespaceConds[$target->getNamespace()][] = $db->makeList( [
 400                                 'wl_title = ' . $db->addQuotes( $target->getDBkey() ),
 401                                 $db->makeList( [
 402                                         'wl_notificationtimestamp >= ' . $db->addQuotes( $db->timestamp( $threshold ) ),
 403                                         'wl_notificationtimestamp IS NULL'
 404                                 ], LIST_OR )
 405                         ], LIST_AND );
 406                 }
 407
 408                 $conds = [];
 409                 foreach ( $namespaceConds as $namespace => $pageConds ) {
 410                         $conds[] = $db->makeList( [
 411                                 'wl_namespace = ' . $namespace,
 412                                 '(' . $db->makeList( $pageConds, LIST_OR ) . ')'
 413                         ], LIST_AND );
 414                 }
 415
 416                 if ( $missingTargets ) {
 417                         $lb = new LinkBatch( $missingTargets );
 418                         $conds[] = $lb->constructSet( 'wl', $db );
 419                 }
 420
 421                 return $db->makeList( $conds, LIST_OR );
 422         }
 423
 424         /**
 425          * Get an item (may be cached)
 426          *
 427          * @param User $user
 428          * @param LinkTarget $target
 429          *
 430          * @return WatchedItem|false
 431          */
 432         public function getWatchedItem( User $user, LinkTarget $target ) {
 433                 if ( $user->isAnon() ) {
 434                         return false;
 435                 }
 436
 437                 $cached = $this->getCached( $user, $target );
 438                 if ( $cached ) {
 439                         $this->stats->increment( 'WatchedItemStore.getWatchedItem.cached' );
 440                         return $cached;
 441                 }
 442                 $this->stats->increment( 'WatchedItemStore.getWatchedItem.load' );
 443                 return $this->loadWatchedItem( $user, $target );
 444         }
 445
 446         /**
 447          * Loads an item from the db
 448          *
 449          * @param User $user
 450          * @param LinkTarget $target
 451          *
 452          * @return WatchedItem|false
 453          */
 454         public function loadWatchedItem( User $user, LinkTarget $target ) {
 455                 // Only loggedin user can have a watchlist
 456                 if ( $user->isAnon() ) {
 457                         return false;
 458                 }
 459
 460                 $dbr = $this->getConnection( DB_SLAVE );
 461                 $row = $dbr->selectRow(
 462                         'watchlist',
 463                         'wl_notificationtimestamp',
 464                         $this->dbCond( $user, $target ),
 465                         __METHOD__
 466                 );
 467                 $this->reuseConnection( $dbr );
 468
 469                 if ( !$row ) {
 470                         return false;
 471                 }
 472
 473                 $item = new WatchedItem(
 474                         $user,
 475                         $target,
 476                         $row->wl_notificationtimestamp
 477                 );
 478                 $this->cache( $item );
 479
 480                 return $item;
 481         }
 482
 483         /**
 484          * @param User $user
 485          * @param array $options Allowed keys:
 486          *        'forWrite' => bool defaults to false
 487          *        'sort' => string optional sorting by namespace ID and title
 488          *                     one of the self::SORT_* constants
 489          *
 490          * @return WatchedItem[]
 491          */
 492         public function getWatchedItemsForUser( User $user, array $options = [] ) {
 493                 $options += [ 'forWrite' => false ];
 494
 495                 $dbOptions = [];
 496                 if ( array_key_exists( 'sort', $options ) ) {
 497                         Assert::parameter(
 498                                 ( in_array( $options['sort'], [ self::SORT_ASC, self::SORT_DESC ] ) ),
 499                                 '$options[\'sort\']',
 500                                 'must be SORT_ASC or SORT_DESC'
 501                         );
 502                         $dbOptions['ORDER BY'] = [
 503                                 "wl_namespace {$options['sort']}",
 504                                 "wl_title {$options['sort']}"
 505                         ];
 506                 }
 507                 $db = $this->getConnection( $options['forWrite'] ? DB_MASTER : DB_SLAVE );
 508
 509                 $res = $db->select(
 510                         'watchlist',
 511                         [ 'wl_namespace', 'wl_title', 'wl_notificationtimestamp' ],
 512                         [ 'wl_user' => $user->getId() ],
 513                         __METHOD__,
 514                         $dbOptions
 515                 );
 516                 $this->reuseConnection( $db );
 517
 518                 $watchedItems = [];
 519                 foreach ( $res as $row ) {
 520                         // todo these could all be cached at some point?
 521                         $watchedItems[] = new WatchedItem(
 522                                 $user,
 523                                 new TitleValue( (int)$row->wl_namespace, $row->wl_title ),
 524                                 $row->wl_notificationtimestamp
 525                         );
 526                 }
 527
 528                 return $watchedItems;
 529         }
 530
 531         /**
 532          * Must be called separately for Subject & Talk namespaces
 533          *
 534          * @param User $user
 535          * @param LinkTarget $target
 536          *
 537          * @return bool
 538          */
 539         public function isWatched( User $user, LinkTarget $target ) {
 540                 return (bool)$this->getWatchedItem( $user, $target );
 541         }
 542
 543         /**
 544          * @param User $user
 545          * @param LinkTarget[] $targets
 546          *
 547          * @return array multi-dimensional like $return[$namespaceId][$titleString] = $timestamp,
 548          *         where $timestamp is:
 549          *         - string|null value of wl_notificationtimestamp,
 550          *         - false if $target is not watched by $user.
 551          */
 552         public function getNotificationTimestampsBatch( User $user, array $targets ) {
 553                 $timestamps = [];
 554                 foreach ( $targets as $target ) {
 555                         $timestamps[$target->getNamespace()][$target->getDBkey()] = false;
 556                 }
 557
 558                 if ( $user->isAnon() ) {
 559                         return $timestamps;
 560                 }
 561
 562                 $targetsToLoad = [];
 563                 foreach ( $targets as $target ) {
 564                         $cachedItem = $this->getCached( $user, $target );
 565                         if ( $cachedItem ) {
 566                                 $timestamps[$target->getNamespace()][$target->getDBkey()] =
 567                                         $cachedItem->getNotificationTimestamp();
 568                         } else {
 569                                 $targetsToLoad[] = $target;
 570                         }
 571                 }
 572
 573                 if ( !$targetsToLoad ) {
 574                         return $timestamps;
 575                 }
 576
 577                 $dbr = $this->getConnection( DB_SLAVE );
 578
 579                 $lb = new LinkBatch( $targetsToLoad );
 580                 $res = $dbr->select(
 581                         'watchlist',
 582                         [ 'wl_namespace', 'wl_title', 'wl_notificationtimestamp' ],
 583                         [
 584                                 $lb->constructSet( 'wl', $dbr ),
 585                                 'wl_user' => $user->getId(),
 586                         ],
 587                         __METHOD__
 588                 );
 589                 $this->reuseConnection( $dbr );
 590
 591                 foreach ( $res as $row ) {
 592                         $timestamps[$row->wl_namespace][$row->wl_title] = $row->wl_notificationtimestamp;
 593                 }
 594
 595                 return $timestamps;
 596         }
 597
 598         /**
 599          * Must be called separately for Subject & Talk namespaces
 600          *
 601          * @param User $user
 602          * @param LinkTarget $target
 603          */
 604         public function addWatch( User $user, LinkTarget $target ) {
 605                 $this->addWatchBatchForUser( $user, [ $target ] );
 606         }
 607
 608         /**
 609          * @param User $user
 610          * @param LinkTarget[] $targets
 611          *
 612          * @return bool success
 613          */
 614         public function addWatchBatchForUser( User $user, array $targets ) {
 615                 if ( $this->loadBalancer->getReadOnlyReason() !== false ) {
 616                         return false;
 617                 }
 618                 // Only loggedin user can have a watchlist
 619                 if ( $user->isAnon() ) {
 620                         return false;
 621                 }
 622
 623                 if ( !$targets ) {
 624                         return true;
 625                 }
 626
 627                 $rows = [];
 628                 foreach ( $targets as $target ) {
 629                         $rows[] = [
 630                                 'wl_user' => $user->getId(),
 631                                 'wl_namespace' => $target->getNamespace(),
 632                                 'wl_title' => $target->getDBkey(),
 633                                 'wl_notificationtimestamp' => null,
 634                         ];
 635                         $this->uncache( $user, $target );
 636                 }
 637
 638                 $dbw = $this->getConnection( DB_MASTER );
 639                 foreach ( array_chunk( $rows, 100 ) as $toInsert ) {
 640                         // Use INSERT IGNORE to avoid overwriting the notification timestamp
 641                         // if there's already an entry for this page
 642                         $dbw->insert( 'watchlist', $toInsert, __METHOD__, 'IGNORE' );
 643                 }
 644                 $this->reuseConnection( $dbw );
 645
 646                 return true;
 647         }
 648
 649         /**
 650          * Removes the an entry for the User watching the LinkTarget
 651          * Must be called separately for Subject & Talk namespaces
 652          *
 653          * @param User $user
 654          * @param LinkTarget $target
 655          *
 656          * @return bool success
 657          * @throws DBUnexpectedError
 658          * @throws MWException
 659          */
 660         public function removeWatch( User $user, LinkTarget $target ) {
 661                 // Only logged in user can have a watchlist
 662                 if ( $this->loadBalancer->getReadOnlyReason() !== false || $user->isAnon() ) {
 663                         return false;
 664                 }
 665
 666                 $this->uncache( $user, $target );
 667
 668                 $dbw = $this->getConnection( DB_MASTER );
 669                 $dbw->delete( 'watchlist',
 670                         [
 671                                 'wl_user' => $user->getId(),
 672                                 'wl_namespace' => $target->getNamespace(),
 673                                 'wl_title' => $target->getDBkey(),
 674                         ], __METHOD__
 675                 );
 676                 $success = (bool)$dbw->affectedRows();
 677                 $this->reuseConnection( $dbw );
 678
 679                 return $success;
 680         }
 681
 682         /**
 683          * @param User $user The user to set the timestamp for
 684          * @param string $timestamp Set the update timestamp to this value
 685          * @param LinkTarget[] $targets List of targets to update. Default to all targets
 686          *
 687          * @return bool success
 688          */
 689         public function setNotificationTimestampsForUser( User $user, $timestamp, array $targets = [] ) {
 690                 // Only loggedin user can have a watchlist
 691                 if ( $user->isAnon() ) {
 692                         return false;
 693                 }
 694
 695                 $dbw = $this->getConnection( DB_MASTER );
 696
 697                 $conds = [ 'wl_user' => $user->getId() ];
 698                 if ( $targets ) {
 699                         $batch = new LinkBatch( $targets );
 700                         $conds[] = $batch->constructSet( 'wl', $dbw );
 701                 }
 702
 703                 $success = $dbw->update(
 704                         'watchlist',
 705                         [ 'wl_notificationtimestamp' => $dbw->timestamp( $timestamp ) ],
 706                         $conds,
 707                         __METHOD__
 708                 );
 709
 710                 $this->reuseConnection( $dbw );
 711
 712                 $this->uncacheUser( $user );
 713
 714                 return $success;
 715         }
 716
 717         /**
 718          * @param User $editor The editor that triggered the update. Their notification
 719          *  timestamp will not be updated(they have already seen it)
 720          * @param LinkTarget $target The target to update timestamps for
 721          * @param string $timestamp Set the update timestamp to this value
 722          *
 723          * @return int[] Array of user IDs the timestamp has been updated for
 724          */
 725         public function updateNotificationTimestamp( User $editor, LinkTarget $target, $timestamp ) {
 726                 $dbw = $this->getConnection( DB_MASTER );
 727                 $res = $dbw->select( [ 'watchlist' ],
 728                         [ 'wl_user' ],
 729                         [
 730                                 'wl_user != ' . intval( $editor->getId() ),
 731                                 'wl_namespace' => $target->getNamespace(),
 732                                 'wl_title' => $target->getDBkey(),
 733                                 'wl_notificationtimestamp IS NULL',
 734                         ], __METHOD__
 735                 );
 736
 737                 $watchers = [];
 738                 foreach ( $res as $row ) {
 739                         $watchers[] = intval( $row->wl_user );
 740                 }
 741
 742                 if ( $watchers ) {
 743                         // Update wl_notificationtimestamp for all watching users except the editor
 744                         $fname = __METHOD__;
 745                         $dbw->onTransactionIdle(
 746                                 function () use ( $dbw, $timestamp, $watchers, $target, $fname ) {
 747                                         $dbw->update( 'watchlist',
 748                                                 [ /* SET */
 749                                                         'wl_notificationtimestamp' => $dbw->timestamp( $timestamp )
 750                                                 ], [ /* WHERE */
 751                                                         'wl_user' => $watchers,
 752                                                         'wl_namespace' => $target->getNamespace(),
 753                                                         'wl_title' => $target->getDBkey(),
 754                                                 ], $fname
 755                                         );
 756                                         $this->uncacheLinkTarget( $target );
 757                                 }
 758                         );
 759                 }
 760
 761                 $this->reuseConnection( $dbw );
 762
 763                 return $watchers;
 764         }
 765
 766         /**
 767          * Reset the notification timestamp of this entry
 768          *
 769          * @param User $user
 770          * @param Title $title
 771          * @param string $force Whether to force the write query to be executed even if the
 772          *    page is not watched or the notification timestamp is already NULL.
 773          *    'force' in order to force
 774          * @param int $oldid The revision id being viewed. If not given or 0, latest revision is assumed.
 775          *
 776          * @return bool success
 777          */
 778         public function resetNotificationTimestamp( User $user, Title $title, $force = '', $oldid = 0 ) {
 779                 // Only loggedin user can have a watchlist
 780                 if ( $this->loadBalancer->getReadOnlyReason() !== false || $user->isAnon() ) {
 781                         return false;
 782                 }
 783
 784                 $item = null;
 785                 if ( $force != 'force' ) {
 786                         $item = $this->loadWatchedItem( $user, $title );
 787                         if ( !$item || $item->getNotificationTimestamp() === null ) {
 788                                 return false;
 789                         }
 790                 }
 791
 792                 // If the page is watched by the user (or may be watched), update the timestamp
 793                 $job = new ActivityUpdateJob(
 794                         $title,
 795                         [
 796                                 'type'      => 'updateWatchlistNotification',
 797                                 'userid'    => $user->getId(),
 798                                 'notifTime' => $this->getNotificationTimestamp( $user, $title, $item, $force, $oldid ),
 799                                 'curTime'   => time()
 800                         ]
 801                 );
 802
 803                 // Try to run this post-send
 804                 // Calls DeferredUpdates::addCallableUpdate in normal operation
 805                 call_user_func(
 806                         $this->deferredUpdatesAddCallableUpdateCallback,
 807                         function() use ( $job ) {
 808                                 $job->run();
 809                         }
 810                 );
 811
 812                 $this->uncache( $user, $title );
 813
 814                 return true;
 815         }
 816
 817         private function getNotificationTimestamp( User $user, Title $title, $item, $force, $oldid ) {
 818                 if ( !$oldid ) {
 819                         // No oldid given, assuming latest revision; clear the timestamp.
 820                         return null;
 821                 }
 822
 823                 if ( !$title->getNextRevisionID( $oldid ) ) {
 824                         // Oldid given and is the latest revision for this title; clear the timestamp.
 825                         return null;
 826                 }
 827
 828                 if ( $item === null ) {
 829                         $item = $this->loadWatchedItem( $user, $title );
 830                 }
 831
 832                 if ( !$item ) {
 833                         // This can only happen if $force is enabled.
 834                         return null;
 835                 }
 836
 837                 // Oldid given and isn't the latest; update the timestamp.
 838                 // This will result in no further notification emails being sent!
 839                 // Calls Revision::getTimestampFromId in normal operation
 840                 $notificationTimestamp = call_user_func(
 841                         $this->revisionGetTimestampFromIdCallback,
 842                         $title,
 843                         $oldid
 844                 );
 845
 846                 // We need to go one second to the future because of various strict comparisons
 847                 // throughout the codebase
 848                 $ts = new MWTimestamp( $notificationTimestamp );
 849                 $ts->timestamp->add( new DateInterval( 'PT1S' ) );
 850                 $notificationTimestamp = $ts->getTimestamp( TS_MW );
 851
 852                 if ( $notificationTimestamp < $item->getNotificationTimestamp() ) {
 853                         if ( $force != 'force' ) {
 854                                 return false;
 855                         } else {
 856                                 // This is a little silly…
 857                                 return $item->getNotificationTimestamp();
 858                         }
 859                 }
 860
 861                 return $notificationTimestamp;
 862         }
 863
 864         /**
 865          * @param User $user
 866          * @param int $unreadLimit
 867          *
 868          * @return int|bool The number of unread notifications
 869          *                  true if greater than or equal to $unreadLimit
 870          */
 871         public function countUnreadNotifications( User $user, $unreadLimit = null ) {
 872                 $queryOptions = [];
 873                 if ( $unreadLimit !== null ) {
 874                         $unreadLimit = (int)$unreadLimit;
 875                         $queryOptions['LIMIT'] = $unreadLimit;
 876                 }
 877
 878                 $dbr = $this->getConnection( DB_SLAVE );
 879                 $rowCount = $dbr->selectRowCount(
 880                         'watchlist',
 881                         '1',
 882                         [
 883                                 'wl_user' => $user->getId(),
 884                                 'wl_notificationtimestamp IS NOT NULL',
 885                         ],
 886                         __METHOD__,
 887                         $queryOptions
 888                 );
 889                 $this->reuseConnection( $dbr );
 890
 891                 if ( !isset( $unreadLimit ) ) {
 892                         return $rowCount;
 893                 }
 894
 895                 if ( $rowCount >= $unreadLimit ) {
 896                         return true;
 897                 }
 898
 899                 return $rowCount;
 900         }
 901
 902         /**
 903          * Check if the given title already is watched by the user, and if so
 904          * add a watch for the new title.
 905          *
 906          * To be used for page renames and such.
 907          *
 908          * @param LinkTarget $oldTarget
 909          * @param LinkTarget $newTarget
 910          */
 911         public function duplicateAllAssociatedEntries( LinkTarget $oldTarget, LinkTarget $newTarget ) {
 912                 $oldTarget = Title::newFromLinkTarget( $oldTarget );
 913                 $newTarget = Title::newFromLinkTarget( $newTarget );
 914
 915                 $this->duplicateEntry( $oldTarget->getSubjectPage(), $newTarget->getSubjectPage() );
 916                 $this->duplicateEntry( $oldTarget->getTalkPage(), $newTarget->getTalkPage() );
 917         }
 918
 919         /**
 920          * Check if the given title already is watched by the user, and if so
 921          * add a watch for the new title.
 922          *
 923          * To be used for page renames and such.
 924          * This must be called separately for Subject and Talk pages
 925          *
 926          * @param LinkTarget $oldTarget
 927          * @param LinkTarget $newTarget
 928          */
 929         public function duplicateEntry( LinkTarget $oldTarget, LinkTarget $newTarget ) {
 930                 $dbw = $this->getConnection( DB_MASTER );
 931
 932                 $result = $dbw->select(
 933                         'watchlist',
 934                         [ 'wl_user', 'wl_notificationtimestamp' ],
 935                         [
 936                                 'wl_namespace' => $oldTarget->getNamespace(),
 937                                 'wl_title' => $oldTarget->getDBkey(),
 938                         ],
 939                         __METHOD__,
 940                         [ 'FOR UPDATE' ]
 941                 );
 942
 943                 $newNamespace = $newTarget->getNamespace();
 944                 $newDBkey = $newTarget->getDBkey();
 945
 946                 # Construct array to replace into the watchlist
 947                 $values = [];
 948                 foreach ( $result as $row ) {
 949                         $values[] = [
 950                                 'wl_user' => $row->wl_user,
 951                                 'wl_namespace' => $newNamespace,
 952                                 'wl_title' => $newDBkey,
 953                                 'wl_notificationtimestamp' => $row->wl_notificationtimestamp,
 954                         ];
 955                 }
 956
 957                 if ( !empty( $values ) ) {
 958                         # Perform replace
 959                         # Note that multi-row replace is very efficient for MySQL but may be inefficient for
 960                         # some other DBMSes, mostly due to poor simulation by us
 961                         $dbw->replace(
 962                                 'watchlist',
 963                                 [ [ 'wl_user', 'wl_namespace', 'wl_title' ] ],
 964                                 $values,
 965                                 __METHOD__
 966                         );
 967                 }
 968
 969                 $this->reuseConnection( $dbw );
 970         }
 971
 972 }