includes/Revision.php

   1 <?php
   2 /**
   3  * Representation of a page version.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  */
  22
  23 use MediaWiki\Revision\MutableRevisionRecord;
  24 use MediaWiki\Revision\RevisionAccessException;
  25 use MediaWiki\Revision\RevisionFactory;
  26 use MediaWiki\Revision\RevisionLookup;
  27 use MediaWiki\Revision\RevisionRecord;
  28 use MediaWiki\Revision\RevisionStore;
  29 use MediaWiki\Revision\RevisionStoreRecord;
  30 use MediaWiki\Revision\SlotRecord;
  31 use MediaWiki\Storage\SqlBlobStore;
  32 use Wikimedia\Rdbms\IDatabase;
  33 use MediaWiki\Linker\LinkTarget;
  34 use MediaWiki\MediaWikiServices;
  35 use Wikimedia\Rdbms\ResultWrapper;
  36 use Wikimedia\Rdbms\FakeResultWrapper;
  37
  38 /**
  39  * @deprecated since 1.31, use RevisionRecord, RevisionStore, and BlobStore instead.
  40  */
  41 class Revision implements IDBAccessObject {
  42
  43         /** @var RevisionRecord */
  44         protected $mRecord;
  45
  46         // Revision deletion constants
  47         const DELETED_TEXT = RevisionRecord::DELETED_TEXT;
  48         const DELETED_COMMENT = RevisionRecord::DELETED_COMMENT;
  49         const DELETED_USER = RevisionRecord::DELETED_USER;
  50         const DELETED_RESTRICTED = RevisionRecord::DELETED_RESTRICTED;
  51         const SUPPRESSED_USER = RevisionRecord::SUPPRESSED_USER;
  52         const SUPPRESSED_ALL = RevisionRecord::SUPPRESSED_ALL;
  53
  54         // Audience options for accessors
  55         const FOR_PUBLIC = RevisionRecord::FOR_PUBLIC;
  56         const FOR_THIS_USER = RevisionRecord::FOR_THIS_USER;
  57         const RAW = RevisionRecord::RAW;
  58
  59         const TEXT_CACHE_GROUP = SqlBlobStore::TEXT_CACHE_GROUP;
  60
  61         /**
  62          * @return RevisionStore
  63          */
  64         protected static function getRevisionStore() {
  65                 return MediaWikiServices::getInstance()->getRevisionStore();
  66         }
  67
  68         /**
  69          * @return RevisionLookup
  70          */
  71         protected static function getRevisionLookup() {
  72                 return MediaWikiServices::getInstance()->getRevisionLookup();
  73         }
  74
  75         /**
  76          * @return RevisionFactory
  77          */
  78         protected static function getRevisionFactory() {
  79                 return MediaWikiServices::getInstance()->getRevisionFactory();
  80         }
  81
  82         /**
  83          * @param bool|string $wiki The ID of the target wiki database. Use false for the local wiki.
  84          *
  85          * @return SqlBlobStore
  86          */
  87         protected static function getBlobStore( $wiki = false ) {
  88                 $store = MediaWikiServices::getInstance()
  89                         ->getBlobStoreFactory()
  90                         ->newSqlBlobStore( $wiki );
  91
  92                 if ( !$store instanceof SqlBlobStore ) {
  93                         throw new RuntimeException(
  94                                 'The backwards compatibility code in Revision currently requires the BlobStore '
  95                                 . 'service to be an SqlBlobStore instance, but it is a ' . get_class( $store )
  96                         );
  97                 }
  98
  99                 return $store;
 100         }
 101
 102         /**
 103          * Load a page revision from a given revision ID number.
 104          * Returns null if no such revision can be found.
 105          *
 106          * $flags include:
 107          *      Revision::READ_LATEST  : Select the data from the master
 108          *      Revision::READ_LOCKING : Select & lock the data from the master
 109          *
 110          * @param int $id
 111          * @param int $flags (optional)
 112          * @return Revision|null
 113          */
 114         public static function newFromId( $id, $flags = 0 ) {
 115                 $rec = self::getRevisionLookup()->getRevisionById( $id, $flags );
 116                 return $rec === null ? null : new Revision( $rec, $flags );
 117         }
 118
 119         /**
 120          * Load either the current, or a specified, revision
 121          * that's attached to a given link target. If not attached
 122          * to that link target, will return null.
 123          *
 124          * $flags include:
 125          *      Revision::READ_LATEST  : Select the data from the master
 126          *      Revision::READ_LOCKING : Select & lock the data from the master
 127          *
 128          * @param LinkTarget $linkTarget
 129          * @param int $id (optional)
 130          * @param int $flags Bitfield (optional)
 131          * @return Revision|null
 132          */
 133         public static function newFromTitle( LinkTarget $linkTarget, $id = 0, $flags = 0 ) {
 134                 $rec = self::getRevisionLookup()->getRevisionByTitle( $linkTarget, $id, $flags );
 135                 return $rec === null ? null : new Revision( $rec, $flags );
 136         }
 137
 138         /**
 139          * Load either the current, or a specified, revision
 140          * that's attached to a given page ID.
 141          * Returns null if no such revision can be found.
 142          *
 143          * $flags include:
 144          *      Revision::READ_LATEST  : Select the data from the master (since 1.20)
 145          *      Revision::READ_LOCKING : Select & lock the data from the master
 146          *
 147          * @param int $pageId
 148          * @param int $revId (optional)
 149          * @param int $flags Bitfield (optional)
 150          * @return Revision|null
 151          */
 152         public static function newFromPageId( $pageId, $revId = 0, $flags = 0 ) {
 153                 $rec = self::getRevisionLookup()->getRevisionByPageId( $pageId, $revId, $flags );
 154                 return $rec === null ? null : new Revision( $rec, $flags );
 155         }
 156
 157         /**
 158          * Make a fake revision object from an archive table row. This is queried
 159          * for permissions or even inserted (as in Special:Undelete)
 160          *
 161          * @param object $row
 162          * @param array $overrides
 163          *
 164          * @throws MWException
 165          * @return Revision
 166          */
 167         public static function newFromArchiveRow( $row, $overrides = [] ) {
 168                 /**
 169                  * MCR Migration: https://phabricator.wikimedia.org/T183564
 170                  * This method used to overwrite attributes, then passed to Revision::__construct
 171                  * RevisionStore::newRevisionFromArchiveRow instead overrides row field names
 172                  * So do a conversion here.
 173                  */
 174                 if ( array_key_exists( 'page', $overrides ) ) {
 175                         $overrides['page_id'] = $overrides['page'];
 176                         unset( $overrides['page'] );
 177                 }
 178
 179                 /**
 180                  * We require a Title for both the Revision object and the RevisionRecord.
 181                  * Below is duplicated logic from RevisionStore::newRevisionFromArchiveRow
 182                  * to fetch a title in order pass it into the Revision object.
 183                  */
 184                 $title = null;
 185                 if ( isset( $overrides['title'] ) ) {
 186                         if ( !( $overrides['title'] instanceof Title ) ) {
 187                                 throw new MWException( 'title field override must contain a Title object.' );
 188                         }
 189
 190                         $title = $overrides['title'];
 191                 }
 192                 if ( $title !== null ) {
 193                         if ( isset( $row->ar_namespace ) && isset( $row->ar_title ) ) {
 194                                 $title = Title::makeTitle( $row->ar_namespace, $row->ar_title );
 195                         } else {
 196                                 throw new InvalidArgumentException(
 197                                         'A Title or ar_namespace and ar_title must be given'
 198                                 );
 199                         }
 200                 }
 201
 202                 $rec = self::getRevisionFactory()->newRevisionFromArchiveRow( $row, 0, $title, $overrides );
 203                 return new Revision( $rec, self::READ_NORMAL, $title );
 204         }
 205
 206         /**
 207          * @since 1.19
 208          *
 209          * MCR migration note: replaced by RevisionStore::newRevisionFromRow(). Note that
 210          * newFromRow() also accepts arrays, while newRevisionFromRow() does not. Instead,
 211          * a MutableRevisionRecord should be constructed directly.
 212          * RevisionStore::newMutableRevisionFromArray() can be used as a temporary replacement,
 213          * but should be avoided.
 214          *
 215          * @param object|array $row
 216          * @return Revision
 217          */
 218         public static function newFromRow( $row ) {
 219                 if ( is_array( $row ) ) {
 220                         $rec = self::getRevisionFactory()->newMutableRevisionFromArray( $row );
 221                 } else {
 222                         $rec = self::getRevisionFactory()->newRevisionFromRow( $row );
 223                 }
 224
 225                 return new Revision( $rec );
 226         }
 227
 228         /**
 229          * Load a page revision from a given revision ID number.
 230          * Returns null if no such revision can be found.
 231          *
 232          * @deprecated since 1.31, use RevisionStore::getRevisionById() instead.
 233          *
 234          * @param IDatabase $db
 235          * @param int $id
 236          * @return Revision|null
 237          */
 238         public static function loadFromId( $db, $id ) {
 239                 wfDeprecated( __METHOD__, '1.31' ); // no known callers
 240                 $rec = self::getRevisionStore()->loadRevisionFromId( $db, $id );
 241                 return $rec === null ? null : new Revision( $rec );
 242         }
 243
 244         /**
 245          * Load either the current, or a specified, revision
 246          * that's attached to a given page. If not attached
 247          * to that page, will return null.
 248          *
 249          * @deprecated since 1.31, use RevisionStore::getRevisionByPageId() instead.
 250          *
 251          * @param IDatabase $db
 252          * @param int $pageid
 253          * @param int $id
 254          * @return Revision|null
 255          */
 256         public static function loadFromPageId( $db, $pageid, $id = 0 ) {
 257                 $rec = self::getRevisionStore()->loadRevisionFromPageId( $db, $pageid, $id );
 258                 return $rec === null ? null : new Revision( $rec );
 259         }
 260
 261         /**
 262          * Load either the current, or a specified, revision
 263          * that's attached to a given page. If not attached
 264          * to that page, will return null.
 265          *
 266          * @deprecated since 1.31, use RevisionStore::getRevisionByTitle() instead.
 267          *
 268          * @param IDatabase $db
 269          * @param Title $title
 270          * @param int $id
 271          * @return Revision|null
 272          */
 273         public static function loadFromTitle( $db, $title, $id = 0 ) {
 274                 $rec = self::getRevisionStore()->loadRevisionFromTitle( $db, $title, $id );
 275                 return $rec === null ? null : new Revision( $rec );
 276         }
 277
 278         /**
 279          * Load the revision for the given title with the given timestamp.
 280          * WARNING: Timestamps may in some circumstances not be unique,
 281          * so this isn't the best key to use.
 282          *
 283          * @deprecated since 1.31, use RevisionStore::getRevisionByTimestamp()
 284          *   or RevisionStore::loadRevisionFromTimestamp() instead.
 285          *
 286          * @param IDatabase $db
 287          * @param Title $title
 288          * @param string $timestamp
 289          * @return Revision|null
 290          */
 291         public static function loadFromTimestamp( $db, $title, $timestamp ) {
 292                 $rec = self::getRevisionStore()->loadRevisionFromTimestamp( $db, $title, $timestamp );
 293                 return $rec === null ? null : new Revision( $rec );
 294         }
 295
 296         /**
 297          * Return a wrapper for a series of database rows to
 298          * fetch all of a given page's revisions in turn.
 299          * Each row can be fed to the constructor to get objects.
 300          *
 301          * @param LinkTarget $title
 302          * @return ResultWrapper
 303          * @deprecated Since 1.28, no callers in core nor in known extensions. No-op since 1.31.
 304          */
 305         public static function fetchRevision( LinkTarget $title ) {
 306                 wfDeprecated( __METHOD__, '1.31' );
 307                 return new FakeResultWrapper( [] );
 308         }
 309
 310         /**
 311          * Return the value of a select() JOIN conds array for the user table.
 312          * This will get user table rows for logged-in users.
 313          * @since 1.19
 314          * @deprecated since 1.31, use RevisionStore::getQueryInfo( [ 'user' ] ) instead.
 315          * @return array
 316          */
 317         public static function userJoinCond() {
 318                 global $wgActorTableSchemaMigrationStage;
 319
 320                 wfDeprecated( __METHOD__, '1.31' );
 321                 if ( $wgActorTableSchemaMigrationStage & SCHEMA_COMPAT_READ_NEW ) {
 322                         // If code is using this instead of self::getQueryInfo(), there's
 323                         // no way the join it's trying to do can work once the old fields
 324                         // aren't being used anymore.
 325                         throw new BadMethodCallException(
 326                                 'Cannot use ' . __METHOD__
 327                                         . ' when $wgActorTableSchemaMigrationStage has SCHEMA_COMPAT_READ_NEW'
 328                         );
 329                 }
 330
 331                 return [ 'LEFT JOIN', [ 'rev_user != 0', 'user_id = rev_user' ] ];
 332         }
 333
 334         /**
 335          * Return the value of a select() page conds array for the page table.
 336          * This will assure that the revision(s) are not orphaned from live pages.
 337          * @since 1.19
 338          * @deprecated since 1.31, use RevisionStore::getQueryInfo( [ 'page' ] ) instead.
 339          * @return array
 340          */
 341         public static function pageJoinCond() {
 342                 wfDeprecated( __METHOD__, '1.31' );
 343                 return [ 'INNER JOIN', [ 'page_id = rev_page' ] ];
 344         }
 345
 346         /**
 347          * Return the list of revision fields that should be selected to create
 348          * a new revision.
 349          * @deprecated since 1.31, use RevisionStore::getQueryInfo() instead.
 350          * @return array
 351          */
 352         public static function selectFields() {
 353                 global $wgContentHandlerUseDB, $wgActorTableSchemaMigrationStage;
 354                 global $wgMultiContentRevisionSchemaMigrationStage;
 355
 356                 if ( $wgActorTableSchemaMigrationStage & SCHEMA_COMPAT_READ_NEW ) {
 357                         // If code is using this instead of self::getQueryInfo(), there's a
 358                         // decent chance it's going to try to directly access
 359                         // $row->rev_user or $row->rev_user_text and we can't give it
 360                         // useful values here once those aren't being used anymore.
 361                         throw new BadMethodCallException(
 362                                 'Cannot use ' . __METHOD__
 363                                         . ' when $wgActorTableSchemaMigrationStage has SCHEMA_COMPAT_READ_NEW'
 364                         );
 365                 }
 366
 367                 if ( !( $wgMultiContentRevisionSchemaMigrationStage & SCHEMA_COMPAT_WRITE_OLD ) ) {
 368                         // If code is using this instead of self::getQueryInfo(), there's a
 369                         // decent chance it's going to try to directly access
 370                         // $row->rev_text_id or $row->rev_content_model and we can't give it
 371                         // useful values here once those aren't being written anymore,
 372                         // and may not exist at all.
 373                         throw new BadMethodCallException(
 374                                 'Cannot use ' . __METHOD__ . ' when $wgMultiContentRevisionSchemaMigrationStage '
 375                                 . 'does not have SCHEMA_COMPAT_WRITE_OLD set.'
 376                         );
 377                 }
 378
 379                 wfDeprecated( __METHOD__, '1.31' );
 380
 381                 $fields = [
 382                         'rev_id',
 383                         'rev_page',
 384                         'rev_text_id',
 385                         'rev_timestamp',
 386                         'rev_user_text',
 387                         'rev_user',
 388                         'rev_actor' => 'NULL',
 389                         'rev_minor_edit',
 390                         'rev_deleted',
 391                         'rev_len',
 392                         'rev_parent_id',
 393                         'rev_sha1',
 394                 ];
 395
 396                 $fields += CommentStore::getStore()->getFields( 'rev_comment' );
 397
 398                 if ( $wgContentHandlerUseDB ) {
 399                         $fields[] = 'rev_content_format';
 400                         $fields[] = 'rev_content_model';
 401                 }
 402
 403                 return $fields;
 404         }
 405
 406         /**
 407          * Return the list of revision fields that should be selected to create
 408          * a new revision from an archive row.
 409          * @deprecated since 1.31, use RevisionStore::getArchiveQueryInfo() instead.
 410          * @return array
 411          */
 412         public static function selectArchiveFields() {
 413                 global $wgContentHandlerUseDB, $wgActorTableSchemaMigrationStage;
 414                 global $wgMultiContentRevisionSchemaMigrationStage;
 415
 416                 if ( $wgActorTableSchemaMigrationStage & SCHEMA_COMPAT_READ_NEW ) {
 417                         // If code is using this instead of self::getQueryInfo(), there's a
 418                         // decent chance it's going to try to directly access
 419                         // $row->ar_user or $row->ar_user_text and we can't give it
 420                         // useful values here once those aren't being used anymore.
 421                         throw new BadMethodCallException(
 422                                 'Cannot use ' . __METHOD__
 423                                         . ' when $wgActorTableSchemaMigrationStage has SCHEMA_COMPAT_READ_NEW'
 424                         );
 425                 }
 426
 427                 if ( !( $wgMultiContentRevisionSchemaMigrationStage & SCHEMA_COMPAT_WRITE_OLD ) ) {
 428                         // If code is using this instead of self::getQueryInfo(), there's a
 429                         // decent chance it's going to try to directly access
 430                         // $row->ar_text_id or $row->ar_content_model and we can't give it
 431                         // useful values here once those aren't being written anymore,
 432                         // and may not exist at all.
 433                         throw new BadMethodCallException(
 434                                 'Cannot use ' . __METHOD__ . ' when $wgMultiContentRevisionSchemaMigrationStage '
 435                                 . 'does not have SCHEMA_COMPAT_WRITE_OLD set.'
 436                         );
 437                 }
 438
 439                 wfDeprecated( __METHOD__, '1.31' );
 440
 441                 $fields = [
 442                         'ar_id',
 443                         'ar_page_id',
 444                         'ar_rev_id',
 445                         'ar_text_id',
 446                         'ar_timestamp',
 447                         'ar_user_text',
 448                         'ar_user',
 449                         'ar_actor' => 'NULL',
 450                         'ar_minor_edit',
 451                         'ar_deleted',
 452                         'ar_len',
 453                         'ar_parent_id',
 454                         'ar_sha1',
 455                 ];
 456
 457                 $fields += CommentStore::getStore()->getFields( 'ar_comment' );
 458
 459                 if ( $wgContentHandlerUseDB ) {
 460                         $fields[] = 'ar_content_format';
 461                         $fields[] = 'ar_content_model';
 462                 }
 463                 return $fields;
 464         }
 465
 466         /**
 467          * Return the list of text fields that should be selected to read the
 468          * revision text
 469          * @deprecated since 1.31, use RevisionStore::getQueryInfo( [ 'text' ] ) instead.
 470          * @return array
 471          */
 472         public static function selectTextFields() {
 473                 wfDeprecated( __METHOD__, '1.31' );
 474                 return [
 475                         'old_text',
 476                         'old_flags'
 477                 ];
 478         }
 479
 480         /**
 481          * Return the list of page fields that should be selected from page table
 482          * @deprecated since 1.31, use RevisionStore::getQueryInfo( [ 'page' ] ) instead.
 483          * @return array
 484          */
 485         public static function selectPageFields() {
 486                 wfDeprecated( __METHOD__, '1.31' );
 487                 return [
 488                         'page_namespace',
 489                         'page_title',
 490                         'page_id',
 491                         'page_latest',
 492                         'page_is_redirect',
 493                         'page_len',
 494                 ];
 495         }
 496
 497         /**
 498          * Return the list of user fields that should be selected from user table
 499          * @deprecated since 1.31, use RevisionStore::getQueryInfo( [ 'user' ] ) instead.
 500          * @return array
 501          */
 502         public static function selectUserFields() {
 503                 wfDeprecated( __METHOD__, '1.31' );
 504                 return [ 'user_name' ];
 505         }
 506
 507         /**
 508          * Return the tables, fields, and join conditions to be selected to create
 509          * a new revision object.
 510          * @since 1.31
 511          * @deprecated since 1.31, use RevisionStore::getQueryInfo() instead.
 512          * @param array $options Any combination of the following strings
 513          *  - 'page': Join with the page table, and select fields to identify the page
 514          *  - 'user': Join with the user table, and select the user name
 515          *  - 'text': Join with the text table, and select fields to load page text
 516          * @return array With three keys:
 517          *   - tables: (string[]) to include in the `$table` to `IDatabase->select()`
 518          *   - fields: (string[]) to include in the `$vars` to `IDatabase->select()`
 519          *   - joins: (array) to include in the `$join_conds` to `IDatabase->select()`
 520          */
 521         public static function getQueryInfo( $options = [] ) {
 522                 return self::getRevisionStore()->getQueryInfo( $options );
 523         }
 524
 525         /**
 526          * Return the tables, fields, and join conditions to be selected to create
 527          * a new archived revision object.
 528          * @since 1.31
 529          * @deprecated since 1.31, use RevisionStore::getArchiveQueryInfo() instead.
 530          * @return array With three keys:
 531          *   - tables: (string[]) to include in the `$table` to `IDatabase->select()`
 532          *   - fields: (string[]) to include in the `$vars` to `IDatabase->select()`
 533          *   - joins: (array) to include in the `$join_conds` to `IDatabase->select()`
 534          */
 535         public static function getArchiveQueryInfo() {
 536                 return self::getRevisionStore()->getArchiveQueryInfo();
 537         }
 538
 539         /**
 540          * Do a batched query to get the parent revision lengths
 541          *
 542          * @deprecated in 1.31, use RevisionStore::getRevisionSizes instead.
 543          *
 544          * @param IDatabase $db
 545          * @param array $revIds
 546          * @return array
 547          */
 548         public static function getParentLengths( $db, array $revIds ) {
 549                 return self::getRevisionStore()->listRevisionSizes( $db, $revIds );
 550         }
 551
 552         /**
 553          * @param object|array|RevisionRecord $row Either a database row or an array
 554          * @param int $queryFlags
 555          * @param Title|null $title
 556          *
 557          * @access private
 558          */
 559         function __construct( $row, $queryFlags = 0, Title $title = null ) {
 560                 global $wgUser;
 561
 562                 if ( $row instanceof RevisionRecord ) {
 563                         $this->mRecord = $row;
 564                 } elseif ( is_array( $row ) ) {
 565                         // If no user is specified, fall back to using the global user object, to stay
 566                         // compatible with pre-1.31 behavior.
 567                         if ( !isset( $row['user'] ) && !isset( $row['user_text'] ) ) {
 568                                 $row['user'] = $wgUser;
 569                         }
 570
 571                         $this->mRecord = self::getRevisionFactory()->newMutableRevisionFromArray(
 572                                 $row,
 573                                 $queryFlags,
 574                                 $this->ensureTitle( $row, $queryFlags, $title )
 575                         );
 576                 } elseif ( is_object( $row ) ) {
 577                         $this->mRecord = self::getRevisionFactory()->newRevisionFromRow(
 578                                 $row,
 579                                 $queryFlags,
 580                                 $this->ensureTitle( $row, $queryFlags, $title )
 581                         );
 582                 } else {
 583                         throw new InvalidArgumentException(
 584                                 '$row must be a row object, an associative array, or a RevisionRecord'
 585                         );
 586                 }
 587         }
 588
 589         /**
 590          * Make sure we have *some* Title object for use by the constructor.
 591          * For B/C, the constructor shouldn't fail even for a bad page ID or bad revision ID.
 592          *
 593          * @param array|object $row
 594          * @param int $queryFlags
 595          * @param Title|null $title
 596          *
 597          * @return Title $title if not null, or a Title constructed from information in $row.
 598          */
 599         private function ensureTitle( $row, $queryFlags, $title = null ) {
 600                 if ( $title ) {
 601                         return $title;
 602                 }
 603
 604                 if ( is_array( $row ) ) {
 605                         if ( isset( $row['title'] ) ) {
 606                                 if ( !( $row['title'] instanceof Title ) ) {
 607                                         throw new MWException( 'title field must contain a Title object.' );
 608                                 }
 609
 610                                 return $row['title'];
 611                         }
 612
 613                         $pageId = $row['page'] ?? 0;
 614                         $revId = $row['id'] ?? 0;
 615                 } else {
 616                         $pageId = $row->rev_page ?? 0;
 617                         $revId = $row->rev_id ?? 0;
 618                 }
 619
 620                 try {
 621                         $title = self::getRevisionStore()->getTitle( $pageId, $revId, $queryFlags );
 622                 } catch ( RevisionAccessException $ex ) {
 623                         // construct a dummy title!
 624                         wfLogWarning( __METHOD__ . ': ' . $ex->getMessage() );
 625
 626                         // NOTE: this Title will only be used inside RevisionRecord
 627                         $title = Title::makeTitleSafe( NS_SPECIAL, "Badtitle/ID=$pageId" );
 628                         $title->resetArticleID( $pageId );
 629                 }
 630
 631                 return $title;
 632         }
 633
 634         /**
 635          * @return RevisionRecord
 636          */
 637         public function getRevisionRecord() {
 638                 return $this->mRecord;
 639         }
 640
 641         /**
 642          * Get revision ID
 643          *
 644          * @return int|null
 645          */
 646         public function getId() {
 647                 return $this->mRecord->getId();
 648         }
 649
 650         /**
 651          * Set the revision ID
 652          *
 653          * This should only be used for proposed revisions that turn out to be null edits.
 654          *
 655          * @note Only supported on Revisions that were constructed based on associative arrays,
 656          *       since they are mutable.
 657          *
 658          * @since 1.19
 659          * @param int|string $id
 660          * @throws MWException
 661          */
 662         public function setId( $id ) {
 663                 if ( $this->mRecord instanceof MutableRevisionRecord ) {
 664                         $this->mRecord->setId( intval( $id ) );
 665                 } else {
 666                         throw new MWException( __METHOD__ . ' is not supported on this instance' );
 667                 }
 668         }
 669
 670         /**
 671          * Set the user ID/name
 672          *
 673          * This should only be used for proposed revisions that turn out to be null edits
 674          *
 675          * @note Only supported on Revisions that were constructed based on associative arrays,
 676          *       since they are mutable.
 677          *
 678          * @since 1.28
 679          * @deprecated since 1.31, please reuse old Revision object
 680          * @param int $id User ID
 681          * @param string $name User name
 682          * @throws MWException
 683          */
 684         public function setUserIdAndName( $id, $name ) {
 685                 if ( $this->mRecord instanceof MutableRevisionRecord ) {
 686                         $user = User::newFromAnyId( intval( $id ), $name, null );
 687                         $this->mRecord->setUser( $user );
 688                 } else {
 689                         throw new MWException( __METHOD__ . ' is not supported on this instance' );
 690                 }
 691         }
 692
 693         /**
 694          * @return SlotRecord
 695          */
 696         private function getMainSlotRaw() {
 697                 return $this->mRecord->getSlot( SlotRecord::MAIN, RevisionRecord::RAW );
 698         }
 699
 700         /**
 701          * Get the ID of the row of the text table that contains the content of the
 702          * revision's main slot, if that content is stored in the text table.
 703          *
 704          * If the content is stored elsewhere, this returns null.
 705          *
 706          * @deprecated since 1.31, use RevisionRecord()->getSlot()->getContentAddress() to
 707          * get that actual address that can be used with BlobStore::getBlob(); or use
 708          * RevisionRecord::hasSameContent() to check if two revisions have the same content.
 709          *
 710          * @return int|null
 711          */
 712         public function getTextId() {
 713                 $slot = $this->getMainSlotRaw();
 714                 return $slot->hasAddress()
 715                         ? self::getBlobStore()->getTextIdFromAddress( $slot->getAddress() )
 716                         : null;
 717         }
 718
 719         /**
 720          * Get parent revision ID (the original previous page revision)
 721          *
 722          * @return int|null The ID of the parent revision. 0 indicates that there is no
 723          * parent revision. Null indicates that the parent revision is not known.
 724          */
 725         public function getParentId() {
 726                 return $this->mRecord->getParentId();
 727         }
 728
 729         /**
 730          * Returns the length of the text in this revision, or null if unknown.
 731          *
 732          * @return int|null
 733          */
 734         public function getSize() {
 735                 try {
 736                         return $this->mRecord->getSize();
 737                 } catch ( RevisionAccessException $ex ) {
 738                         return null;
 739                 }
 740         }
 741
 742         /**
 743          * Returns the base36 sha1 of the content in this revision, or null if unknown.
 744          *
 745          * @return string|null
 746          */
 747         public function getSha1() {
 748                 try {
 749                         return $this->mRecord->getSha1();
 750                 } catch ( RevisionAccessException $ex ) {
 751                         return null;
 752                 }
 753         }
 754
 755         /**
 756          * Returns the title of the page associated with this entry.
 757          * Since 1.31, this will never return null.
 758          *
 759          * Will do a query, when title is not set and id is given.
 760          *
 761          * @return Title
 762          */
 763         public function getTitle() {
 764                 $linkTarget = $this->mRecord->getPageAsLinkTarget();
 765                 return Title::newFromLinkTarget( $linkTarget );
 766         }
 767
 768         /**
 769          * Set the title of the revision
 770          *
 771          * @deprecated since 1.31, this is now a noop. Pass the Title to the constructor instead.
 772          *
 773          * @param Title $title
 774          */
 775         public function setTitle( $title ) {
 776                 if ( !$title->equals( $this->getTitle() ) ) {
 777                         throw new InvalidArgumentException(
 778                                 $title->getPrefixedText()
 779                                         . ' is not the same as '
 780                                         . $this->mRecord->getPageAsLinkTarget()->__toString()
 781                         );
 782                 }
 783         }
 784
 785         /**
 786          * Get the page ID
 787          *
 788          * @return int|null
 789          */
 790         public function getPage() {
 791                 return $this->mRecord->getPageId();
 792         }
 793
 794         /**
 795          * Fetch revision's user id if it's available to the specified audience.
 796          * If the specified audience does not have access to it, zero will be
 797          * returned.
 798          *
 799          * @param int $audience One of:
 800          *   Revision::FOR_PUBLIC       to be displayed to all users
 801          *   Revision::FOR_THIS_USER    to be displayed to the given user
 802          *   Revision::RAW              get the ID regardless of permissions
 803          * @param User|null $user User object to check for, only if FOR_THIS_USER is passed
 804          *   to the $audience parameter
 805          * @return int
 806          */
 807         public function getUser( $audience = self::FOR_PUBLIC, User $user = null ) {
 808                 global $wgUser;
 809
 810                 if ( $audience === self::FOR_THIS_USER && !$user ) {
 811                         $user = $wgUser;
 812                 }
 813
 814                 $user = $this->mRecord->getUser( $audience, $user );
 815                 return $user ? $user->getId() : 0;
 816         }
 817
 818         /**
 819          * Fetch revision's username if it's available to the specified audience.
 820          * If the specified audience does not have access to the username, an
 821          * empty string will be returned.
 822          *
 823          * @param int $audience One of:
 824          *   Revision::FOR_PUBLIC       to be displayed to all users
 825          *   Revision::FOR_THIS_USER    to be displayed to the given user
 826          *   Revision::RAW              get the text regardless of permissions
 827          * @param User|null $user User object to check for, only if FOR_THIS_USER is passed
 828          *   to the $audience parameter
 829          * @return string
 830          */
 831         public function getUserText( $audience = self::FOR_PUBLIC, User $user = null ) {
 832                 global $wgUser;
 833
 834                 if ( $audience === self::FOR_THIS_USER && !$user ) {
 835                         $user = $wgUser;
 836                 }
 837
 838                 $user = $this->mRecord->getUser( $audience, $user );
 839                 return $user ? $user->getName() : '';
 840         }
 841         /**
 842          * Fetch revision comment if it's available to the specified audience.
 843          * If the specified audience does not have access to the comment, an
 844          * empty string will be returned.
 845          *
 846          * @param int $audience One of:
 847          *   Revision::FOR_PUBLIC       to be displayed to all users
 848          *   Revision::FOR_THIS_USER    to be displayed to the given user
 849          *   Revision::RAW              get the text regardless of permissions
 850          * @param User|null $user User object to check for, only if FOR_THIS_USER is passed
 851          *   to the $audience parameter
 852          * @return string
 853          */
 854         function getComment( $audience = self::FOR_PUBLIC, User $user = null ) {
 855                 global $wgUser;
 856
 857                 if ( $audience === self::FOR_THIS_USER && !$user ) {
 858                         $user = $wgUser;
 859                 }
 860
 861                 $comment = $this->mRecord->getComment( $audience, $user );
 862                 return $comment === null ? null : $comment->text;
 863         }
 864
 865         /**
 866          * @return bool
 867          */
 868         public function isMinor() {
 869                 return $this->mRecord->isMinor();
 870         }
 871
 872         /**
 873          * @return int Rcid of the unpatrolled row, zero if there isn't one
 874          */
 875         public function isUnpatrolled() {
 876                 return self::getRevisionStore()->getRcIdIfUnpatrolled( $this->mRecord );
 877         }
 878
 879         /**
 880          * Get the RC object belonging to the current revision, if there's one
 881          *
 882          * @param int $flags (optional) $flags include:
 883          *      Revision::READ_LATEST  : Select the data from the master
 884          *
 885          * @since 1.22
 886          * @return RecentChange|null
 887          */
 888         public function getRecentChange( $flags = 0 ) {
 889                 return self::getRevisionStore()->getRecentChange( $this->mRecord, $flags );
 890         }
 891
 892         /**
 893          * @param int $field One of DELETED_* bitfield constants
 894          *
 895          * @return bool
 896          */
 897         public function isDeleted( $field ) {
 898                 return $this->mRecord->isDeleted( $field );
 899         }
 900
 901         /**
 902          * Get the deletion bitfield of the revision
 903          *
 904          * @return int
 905          */
 906         public function getVisibility() {
 907                 return $this->mRecord->getVisibility();
 908         }
 909
 910         /**
 911          * Fetch revision content if it's available to the specified audience.
 912          * If the specified audience does not have the ability to view this
 913          * revision, or the content could not be loaded, null will be returned.
 914          *
 915          * @param int $audience One of:
 916          *   Revision::FOR_PUBLIC       to be displayed to all users
 917          *   Revision::FOR_THIS_USER    to be displayed to $user
 918          *   Revision::RAW              get the text regardless of permissions
 919          * @param User|null $user User object to check for, only if FOR_THIS_USER is passed
 920          *   to the $audience parameter
 921          * @since 1.21
 922          * @return Content|null
 923          */
 924         public function getContent( $audience = self::FOR_PUBLIC, User $user = null ) {
 925                 global $wgUser;
 926
 927                 if ( $audience === self::FOR_THIS_USER && !$user ) {
 928                         $user = $wgUser;
 929                 }
 930
 931                 try {
 932                         return $this->mRecord->getContent( SlotRecord::MAIN, $audience, $user );
 933                 }
 934                 catch ( RevisionAccessException $e ) {
 935                         return null;
 936                 }
 937         }
 938
 939         /**
 940          * Get original serialized data (without checking view restrictions)
 941          *
 942          * @since 1.21
 943          * @deprecated since 1.31, use BlobStore::getBlob instead.
 944          *
 945          * @return string
 946          */
 947         public function getSerializedData() {
 948                 $slot = $this->getMainSlotRaw();
 949                 return $slot->getContent()->serialize();
 950         }
 951
 952         /**
 953          * Returns the content model for the main slot of this revision.
 954          *
 955          * If no content model was stored in the database, the default content model for the title is
 956          * used to determine the content model to use. If no title is know, CONTENT_MODEL_WIKITEXT
 957          * is used as a last resort.
 958          *
 959          * @todo drop this, with MCR, there no longer is a single model associated with a revision.
 960          *
 961          * @return string The content model id associated with this revision,
 962          *     see the CONTENT_MODEL_XXX constants.
 963          */
 964         public function getContentModel() {
 965                 return $this->getMainSlotRaw()->getModel();
 966         }
 967
 968         /**
 969          * Returns the content format for the main slot of this revision.
 970          *
 971          * If no content format was stored in the database, the default format for this
 972          * revision's content model is returned.
 973          *
 974          * @todo drop this, the format is irrelevant to the revision!
 975          *
 976          * @return string The content format id associated with this revision,
 977          *     see the CONTENT_FORMAT_XXX constants.
 978          */
 979         public function getContentFormat() {
 980                 $format = $this->getMainSlotRaw()->getFormat();
 981
 982                 if ( $format === null ) {
 983                         // if no format was stored along with the blob, fall back to default format
 984                         $format = $this->getContentHandler()->getDefaultFormat();
 985                 }
 986
 987                 return $format;
 988         }
 989
 990         /**
 991          * Returns the content handler appropriate for this revision's content model.
 992          *
 993          * @throws MWException
 994          * @return ContentHandler
 995          */
 996         public function getContentHandler() {
 997                 return ContentHandler::getForModelID( $this->getContentModel() );
 998         }
 999
1000         /**
1001          * @return string
1002          */
1003         public function getTimestamp() {
1004                 return $this->mRecord->getTimestamp();
1005         }
1006
1007         /**
1008          * @return bool
1009          */
1010         public function isCurrent() {
1011                 return ( $this->mRecord instanceof RevisionStoreRecord ) && $this->mRecord->isCurrent();
1012         }
1013
1014         /**
1015          * Get previous revision for this title
1016          *
1017          * @return Revision|null
1018          */
1019         public function getPrevious() {
1020                 $title = $this->getTitle();
1021                 $rec = self::getRevisionLookup()->getPreviousRevision( $this->mRecord, $title );
1022                 return $rec === null ? null : new Revision( $rec, self::READ_NORMAL, $title );
1023         }
1024
1025         /**
1026          * Get next revision for this title
1027          *
1028          * @return Revision|null
1029          */
1030         public function getNext() {
1031                 $title = $this->getTitle();
1032                 $rec = self::getRevisionLookup()->getNextRevision( $this->mRecord, $title );
1033                 return $rec === null ? null : new Revision( $rec, self::READ_NORMAL, $title );
1034         }
1035
1036         /**
1037          * Get revision text associated with an old or archive row
1038          *
1039          * Both the flags and the text field must be included. Including the old_id
1040          * field will activate cache usage as long as the $wiki parameter is not set.
1041          *
1042          * @param stdClass $row The text data
1043          * @param string $prefix Table prefix (default 'old_')
1044          * @param string|bool $wiki The name of the wiki to load the revision text from
1045          *   (same as the wiki $row was loaded from) or false to indicate the local
1046          *   wiki (this is the default). Otherwise, it must be a symbolic wiki database
1047          *   identifier as understood by the LoadBalancer class.
1048          * @return string|false Text the text requested or false on failure
1049          */
1050         public static function getRevisionText( $row, $prefix = 'old_', $wiki = false ) {
1051                 $textField = $prefix . 'text';
1052                 $flagsField = $prefix . 'flags';
1053
1054                 if ( isset( $row->$flagsField ) ) {
1055                         $flags = explode( ',', $row->$flagsField );
1056                 } else {
1057                         $flags = [];
1058                 }
1059
1060                 if ( isset( $row->$textField ) ) {
1061                         $text = $row->$textField;
1062                 } else {
1063                         return false;
1064                 }
1065
1066                 $cacheKey = isset( $row->old_id )
1067                         ? SqlBlobStore::makeAddressFromTextId( $row->old_id )
1068                         : null;
1069
1070                 $revisionText = self::getBlobStore( $wiki )->expandBlob( $text, $flags, $cacheKey );
1071
1072                 if ( $revisionText === false ) {
1073                         if ( isset( $row->old_id ) ) {
1074                                 wfLogWarning( __METHOD__ . ": Bad data in text row {$row->old_id}! " );
1075                         } else {
1076                                 wfLogWarning( __METHOD__ . ": Bad data in text row! " );
1077                         }
1078                         return false;
1079                 }
1080
1081                 return $revisionText;
1082         }
1083
1084         /**
1085          * If $wgCompressRevisions is enabled, we will compress data.
1086          * The input string is modified in place.
1087          * Return value is the flags field: contains 'gzip' if the
1088          * data is compressed, and 'utf-8' if we're saving in UTF-8
1089          * mode.
1090          *
1091          * @param mixed &$text Reference to a text
1092          * @return string
1093          */
1094         public static function compressRevisionText( &$text ) {
1095                 return self::getBlobStore()->compressData( $text );
1096         }
1097
1098         /**
1099          * Re-converts revision text according to it's flags.
1100          *
1101          * @param mixed $text Reference to a text
1102          * @param array $flags Compression flags
1103          * @return string|bool Decompressed text, or false on failure
1104          */
1105         public static function decompressRevisionText( $text, $flags ) {
1106                 if ( $text === false ) {
1107                         // Text failed to be fetched; nothing to do
1108                         return false;
1109                 }
1110
1111                 return self::getBlobStore()->decompressData( $text, $flags );
1112         }
1113
1114         /**
1115          * Insert a new revision into the database, returning the new revision ID
1116          * number on success and dies horribly on failure.
1117          *
1118          * @param IDatabase $dbw (master connection)
1119          * @throws MWException
1120          * @return int The revision ID
1121          */
1122         public function insertOn( $dbw ) {
1123                 global $wgUser;
1124
1125                 // Note that $this->mRecord->getId() will typically return null here, but not always,
1126                 // e.g. not when restoring a revision.
1127
1128                 if ( $this->mRecord->getUser( RevisionRecord::RAW ) === null ) {
1129                         if ( $this->mRecord instanceof MutableRevisionRecord ) {
1130                                 $this->mRecord->setUser( $wgUser );
1131                         } else {
1132                                 throw new MWException( 'Cannot insert revision with no associated user.' );
1133                         }
1134                 }
1135
1136                 $rec = self::getRevisionStore()->insertRevisionOn( $this->mRecord, $dbw );
1137
1138                 $this->mRecord = $rec;
1139
1140                 // Avoid PHP 7.1 warning of passing $this by reference
1141                 $revision = $this;
1142
1143                 return $rec->getId();
1144         }
1145
1146         /**
1147          * Get the base 36 SHA-1 value for a string of text
1148          * @param string $text
1149          * @return string
1150          */
1151         public static function base36Sha1( $text ) {
1152                 return SlotRecord::base36Sha1( $text );
1153         }
1154
1155         /**
1156          * Create a new null-revision for insertion into a page's
1157          * history. This will not re-save the text, but simply refer
1158          * to the text from the previous version.
1159          *
1160          * Such revisions can for instance identify page rename
1161          * operations and other such meta-modifications.
1162          *
1163          * @param IDatabase $dbw
1164          * @param int $pageId ID number of the page to read from
1165          * @param string $summary Revision's summary
1166          * @param bool $minor Whether the revision should be considered as minor
1167          * @param User|null $user User object to use or null for $wgUser
1168          * @return Revision|null Revision or null on error
1169          */
1170         public static function newNullRevision( $dbw, $pageId, $summary, $minor, $user = null ) {
1171                 global $wgUser;
1172                 if ( !$user ) {
1173                         $user = $wgUser;
1174                 }
1175
1176                 $comment = CommentStoreComment::newUnsavedComment( $summary, null );
1177
1178                 $title = Title::newFromID( $pageId, Title::GAID_FOR_UPDATE );
1179                 if ( $title === null ) {
1180                         return null;
1181                 }
1182
1183                 $rec = self::getRevisionStore()->newNullRevision( $dbw, $title, $comment, $minor, $user );
1184
1185                 return $rec ? new Revision( $rec ) : null;
1186         }
1187
1188         /**
1189          * Determine if the current user is allowed to view a particular
1190          * field of this revision, if it's marked as deleted.
1191          *
1192          * @param int $field One of self::DELETED_TEXT,
1193          *                              self::DELETED_COMMENT,
1194          *                              self::DELETED_USER
1195          * @param User|null $user User object to check, or null to use $wgUser
1196          * @return bool
1197          */
1198         public function userCan( $field, User $user = null ) {
1199                 return self::userCanBitfield( $this->getVisibility(), $field, $user );
1200         }
1201
1202         /**
1203          * Determine if the current user is allowed to view a particular
1204          * field of this revision, if it's marked as deleted. This is used
1205          * by various classes to avoid duplication.
1206          *
1207          * @param int $bitfield Current field
1208          * @param int $field One of self::DELETED_TEXT = File::DELETED_FILE,
1209          *                               self::DELETED_COMMENT = File::DELETED_COMMENT,
1210          *                               self::DELETED_USER = File::DELETED_USER
1211          * @param User|null $user User object to check, or null to use $wgUser
1212          * @param Title|null $title A Title object to check for per-page restrictions on,
1213          *                          instead of just plain userrights
1214          * @return bool
1215          */
1216         public static function userCanBitfield( $bitfield, $field, User $user = null,
1217                 Title $title = null
1218         ) {
1219                 global $wgUser;
1220
1221                 if ( !$user ) {
1222                         $user = $wgUser;
1223                 }
1224
1225                 return RevisionRecord::userCanBitfield( $bitfield, $field, $user, $title );
1226         }
1227
1228         /**
1229          * Get rev_timestamp from rev_id, without loading the rest of the row
1230          *
1231          * @param Title $title
1232          * @param int $id
1233          * @param int $flags
1234          * @return string|bool False if not found
1235          */
1236         static function getTimestampFromId( $title, $id, $flags = 0 ) {
1237                 return self::getRevisionStore()->getTimestampFromId( $title, $id, $flags );
1238         }
1239
1240         /**
1241          * Get count of revisions per page...not very efficient
1242          *
1243          * @param IDatabase $db
1244          * @param int $id Page id
1245          * @return int
1246          */
1247         static function countByPageId( $db, $id ) {
1248                 return self::getRevisionStore()->countRevisionsByPageId( $db, $id );
1249         }
1250
1251         /**
1252          * Get count of revisions per page...not very efficient
1253          *
1254          * @param IDatabase $db
1255          * @param Title $title
1256          * @return int
1257          */
1258         static function countByTitle( $db, $title ) {
1259                 return self::getRevisionStore()->countRevisionsByTitle( $db, $title );
1260         }
1261
1262         /**
1263          * Check if no edits were made by other users since
1264          * the time a user started editing the page. Limit to
1265          * 50 revisions for the sake of performance.
1266          *
1267          * @since 1.20
1268          * @deprecated since 1.24
1269          *
1270          * @param IDatabase|int $db The Database to perform the check on. May be given as a
1271          *        Database object or a database identifier usable with wfGetDB.
1272          * @param int $pageId The ID of the page in question
1273          * @param int $userId The ID of the user in question
1274          * @param string $since Look at edits since this time
1275          *
1276          * @return bool True if the given user was the only one to edit since the given timestamp
1277          */
1278         public static function userWasLastToEdit( $db, $pageId, $userId, $since ) {
1279                 if ( is_int( $db ) ) {
1280                         $db = wfGetDB( $db );
1281                 }
1282
1283                 return self::getRevisionStore()->userWasLastToEdit( $db, $pageId, $userId, $since );
1284         }
1285
1286         /**
1287          * Load a revision based on a known page ID and current revision ID from the DB
1288          *
1289          * This method allows for the use of caching, though accessing anything that normally
1290          * requires permission checks (aside from the text) will trigger a small DB lookup.
1291          * The title will also be loaded if $pageIdOrTitle is an integer ID.
1292          *
1293          * @param IDatabase $db ignored!
1294          * @param int|Title $pageIdOrTitle Page ID or Title object
1295          * @param int $revId Known current revision of this page. Determined automatically if not given.
1296          * @return Revision|bool Returns false if missing
1297          * @since 1.28
1298          */
1299         public static function newKnownCurrent( IDatabase $db, $pageIdOrTitle, $revId = 0 ) {
1300                 $title = $pageIdOrTitle instanceof Title
1301                         ? $pageIdOrTitle
1302                         : Title::newFromID( $pageIdOrTitle );
1303
1304                 if ( !$title ) {
1305                         return false;
1306                 }
1307
1308                 $record = self::getRevisionLookup()->getKnownCurrentRevision( $title, $revId );
1309                 return $record ? new Revision( $record ) : false;
1310         }
1311 }