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\Storage\MutableRevisionRecord;
  24 use MediaWiki\Storage\RevisionAccessException;
  25 use MediaWiki\Storage\RevisionRecord;
  26 use MediaWiki\Storage\RevisionStore;
  27 use MediaWiki\Storage\RevisionStoreRecord;
  28 use MediaWiki\Storage\SlotRecord;
  29 use MediaWiki\Storage\SqlBlobStore;
  30 use MediaWiki\User\UserIdentityValue;
  31 use Wikimedia\Rdbms\IDatabase;
  32 use MediaWiki\Linker\LinkTarget;
  33 use MediaWiki\MediaWikiServices;
  34 use Wikimedia\Rdbms\ResultWrapper;
  35 use Wikimedia\Rdbms\FakeResultWrapper;
  36
  37 /**
  38  * @deprecated since 1.31, use RevisionRecord, RevisionStore, and BlobStore instead.
  39  */
  40 class Revision implements IDBAccessObject {
  41
  42         /** @var RevisionRecord */
  43         protected $mRecord;
  44
  45         // Revision deletion constants
  46         const DELETED_TEXT = RevisionRecord::DELETED_TEXT;
  47         const DELETED_COMMENT = RevisionRecord::DELETED_COMMENT;
  48         const DELETED_USER = RevisionRecord::DELETED_USER;
  49         const DELETED_RESTRICTED = RevisionRecord::DELETED_RESTRICTED;
  50         const SUPPRESSED_USER = RevisionRecord::SUPPRESSED_USER;
  51         const SUPPRESSED_ALL = RevisionRecord::SUPPRESSED_ALL;
  52
  53         // Audience options for accessors
  54         const FOR_PUBLIC = RevisionRecord::FOR_PUBLIC;
  55         const FOR_THIS_USER = RevisionRecord::FOR_THIS_USER;
  56         const RAW = RevisionRecord::RAW;
  57
  58         const TEXT_CACHE_GROUP = SqlBlobStore::TEXT_CACHE_GROUP;
  59
  60         /**
  61          * @return RevisionStore
  62          */
  63         protected static function getRevisionStore() {
  64                 return MediaWikiServices::getInstance()->getRevisionStore();
  65         }
  66
  67         /**
  68          * @param bool|string $wikiId The ID of the target wiki database. Use false for the local wiki.
  69          *
  70          * @return SqlBlobStore
  71          */
  72         protected static function getBlobStore( $wiki = false ) {
  73                 $store = MediaWikiServices::getInstance()
  74                         ->getBlobStoreFactory()
  75                         ->newSqlBlobStore( $wiki );
  76
  77                 if ( !$store instanceof SqlBlobStore ) {
  78                         throw new RuntimeException(
  79                                 'The backwards compatibility code in Revision currently requires the BlobStore '
  80                                 . 'service to be an SqlBlobStore instance, but it is a ' . get_class( $store )
  81                         );
  82                 }
  83
  84                 return $store;
  85         }
  86
  87         /**
  88          * Load a page revision from a given revision ID number.
  89          * Returns null if no such revision can be found.
  90          *
  91          * $flags include:
  92          *      Revision::READ_LATEST  : Select the data from the master
  93          *      Revision::READ_LOCKING : Select & lock the data from the master
  94          *
  95          * @param int $id
  96          * @param int $flags (optional)
  97          * @return Revision|null
  98          */
  99         public static function newFromId( $id, $flags = 0 ) {
 100                 $rec = self::getRevisionStore()->getRevisionById( $id, $flags );
 101                 return $rec === null ? null : new Revision( $rec, $flags );
 102         }
 103
 104         /**
 105          * Load either the current, or a specified, revision
 106          * that's attached to a given link target. If not attached
 107          * to that link target, will return null.
 108          *
 109          * $flags include:
 110          *      Revision::READ_LATEST  : Select the data from the master
 111          *      Revision::READ_LOCKING : Select & lock the data from the master
 112          *
 113          * @param LinkTarget $linkTarget
 114          * @param int $id (optional)
 115          * @param int $flags Bitfield (optional)
 116          * @return Revision|null
 117          */
 118         public static function newFromTitle( LinkTarget $linkTarget, $id = 0, $flags = 0 ) {
 119                 $rec = self::getRevisionStore()->getRevisionByTitle( $linkTarget, $id, $flags );
 120                 return $rec === null ? null : new Revision( $rec, $flags );
 121         }
 122
 123         /**
 124          * Load either the current, or a specified, revision
 125          * that's attached to a given page ID.
 126          * Returns null if no such revision can be found.
 127          *
 128          * $flags include:
 129          *      Revision::READ_LATEST  : Select the data from the master (since 1.20)
 130          *      Revision::READ_LOCKING : Select & lock the data from the master
 131          *
 132          * @param int $pageId
 133          * @param int $revId (optional)
 134          * @param int $flags Bitfield (optional)
 135          * @return Revision|null
 136          */
 137         public static function newFromPageId( $pageId, $revId = 0, $flags = 0 ) {
 138                 $rec = self::getRevisionStore()->getRevisionByPageId( $pageId, $revId, $flags );
 139                 return $rec === null ? null : new Revision( $rec, $flags );
 140         }
 141
 142         /**
 143          * Make a fake revision object from an archive table row. This is queried
 144          * for permissions or even inserted (as in Special:Undelete)
 145          *
 146          * @param object $row
 147          * @param array $overrides
 148          * @param Title $title (optional)
 149          *
 150          * @throws MWException
 151          * @return Revision
 152          */
 153         public static function newFromArchiveRow( $row, $overrides = [], Title $title = null ) {
 154                 /**
 155                  * MCR Migration: https://phabricator.wikimedia.org/T183564
 156                  * This method used to overwrite attributes, then passed to Revision::__construct
 157                  * RevisionStore::newRevisionFromArchiveRow instead overrides row field names
 158                  * So do a conversion here.
 159                  */
 160                 if ( array_key_exists( 'page', $overrides ) ) {
 161                         $overrides['page_id'] = $overrides['page'];
 162                         unset( $overrides['page'] );
 163                 }
 164
 165                 $rec = self::getRevisionStore()->newRevisionFromArchiveRow( $row, 0, $title, $overrides );
 166                 return new Revision( $rec, self::READ_NORMAL, $title );
 167         }
 168
 169         /**
 170          * @since 1.19
 171          *
 172          * MCR migration note: replaced by RevisionStore::newRevisionFromRow(). Note that
 173          * newFromRow() also accepts arrays, while newRevisionFromRow() does not. Instead,
 174          * a MutableRevisionRecord should be constructed directly. RevisionStore::newRevisionFromArray()
 175          * can be used as a temporary replacement, but should be avoided.
 176          *
 177          * @param object|array $row
 178          * @return Revision
 179          */
 180         public static function newFromRow( $row ) {
 181                 if ( is_array( $row ) ) {
 182                         $rec = self::getRevisionStore()->newMutableRevisionFromArray( $row );
 183                 } else {
 184                         $rec = self::getRevisionStore()->newRevisionFromRow( $row );
 185                 }
 186
 187                 return new Revision( $rec );
 188         }
 189
 190         /**
 191          * Load a page revision from a given revision ID number.
 192          * Returns null if no such revision can be found.
 193          *
 194          * @deprecated since 1.31, use RevisionStore::getRevisionById() instead.
 195          *
 196          * @param IDatabase $db
 197          * @param int $id
 198          * @return Revision|null
 199          */
 200         public static function loadFromId( $db, $id ) {
 201                 wfDeprecated( __METHOD__, '1.31' ); // no known callers
 202                 $rec = self::getRevisionStore()->loadRevisionFromId( $db, $id );
 203                 return $rec === null ? null : new Revision( $rec );
 204         }
 205
 206         /**
 207          * Load either the current, or a specified, revision
 208          * that's attached to a given page. If not attached
 209          * to that page, will return null.
 210          *
 211          * @deprecated since 1.31, use RevisionStore::getRevisionByPageId() instead.
 212          *
 213          * @param IDatabase $db
 214          * @param int $pageid
 215          * @param int $id
 216          * @return Revision|null
 217          */
 218         public static function loadFromPageId( $db, $pageid, $id = 0 ) {
 219                 $rec = self::getRevisionStore()->loadRevisionFromPageId( $db, $pageid, $id );
 220                 return $rec === null ? null : new Revision( $rec );
 221         }
 222
 223         /**
 224          * Load either the current, or a specified, revision
 225          * that's attached to a given page. If not attached
 226          * to that page, will return null.
 227          *
 228          * @deprecated since 1.31, use RevisionStore::getRevisionByTitle() instead.
 229          *
 230          * @param IDatabase $db
 231          * @param Title $title
 232          * @param int $id
 233          * @return Revision|null
 234          */
 235         public static function loadFromTitle( $db, $title, $id = 0 ) {
 236                 $rec = self::getRevisionStore()->loadRevisionFromTitle( $db, $title, $id );
 237                 return $rec === null ? null : new Revision( $rec );
 238         }
 239
 240         /**
 241          * Load the revision for the given title with the given timestamp.
 242          * WARNING: Timestamps may in some circumstances not be unique,
 243          * so this isn't the best key to use.
 244          *
 245          * @deprecated since 1.31, use RevisionStore::loadRevisionFromTimestamp() instead.
 246          *
 247          * @param IDatabase $db
 248          * @param Title $title
 249          * @param string $timestamp
 250          * @return Revision|null
 251          */
 252         public static function loadFromTimestamp( $db, $title, $timestamp ) {
 253                 // XXX: replace loadRevisionFromTimestamp by getRevisionByTimestamp?
 254                 $rec = self::getRevisionStore()->loadRevisionFromTimestamp( $db, $title, $timestamp );
 255                 return $rec === null ? null : new Revision( $rec );
 256         }
 257
 258         /**
 259          * Return a wrapper for a series of database rows to
 260          * fetch all of a given page's revisions in turn.
 261          * Each row can be fed to the constructor to get objects.
 262          *
 263          * @param LinkTarget $title
 264          * @return ResultWrapper
 265          * @deprecated Since 1.28, no callers in core nor in known extensions. No-op since 1.31.
 266          */
 267         public static function fetchRevision( LinkTarget $title ) {
 268                 wfDeprecated( __METHOD__, '1.31' );
 269                 return new FakeResultWrapper( [] );
 270         }
 271
 272         /**
 273          * Return the value of a select() JOIN conds array for the user table.
 274          * This will get user table rows for logged-in users.
 275          * @since 1.19
 276          * @deprecated since 1.31, use RevisionStore::getQueryInfo( [ 'user' ] ) instead.
 277          * @return array
 278          */
 279         public static function userJoinCond() {
 280                 wfDeprecated( __METHOD__, '1.31' );
 281                 return [ 'LEFT JOIN', [ 'rev_user != 0', 'user_id = rev_user' ] ];
 282         }
 283
 284         /**
 285          * Return the value of a select() page conds array for the page table.
 286          * This will assure that the revision(s) are not orphaned from live pages.
 287          * @since 1.19
 288          * @deprecated since 1.31, use RevisionStore::getQueryInfo( [ 'page' ] ) instead.
 289          * @return array
 290          */
 291         public static function pageJoinCond() {
 292                 wfDeprecated( __METHOD__, '1.31' );
 293                 return [ 'INNER JOIN', [ 'page_id = rev_page' ] ];
 294         }
 295
 296         /**
 297          * Return the list of revision fields that should be selected to create
 298          * a new revision.
 299          * @deprecated since 1.31, use RevisionStore::getQueryInfo() instead.
 300          * @return array
 301          */
 302         public static function selectFields() {
 303                 global $wgContentHandlerUseDB;
 304
 305                 wfDeprecated( __METHOD__, '1.31' );
 306
 307                 $fields = [
 308                         'rev_id',
 309                         'rev_page',
 310                         'rev_text_id',
 311                         'rev_timestamp',
 312                         'rev_user_text',
 313                         'rev_user',
 314                         'rev_minor_edit',
 315                         'rev_deleted',
 316                         'rev_len',
 317                         'rev_parent_id',
 318                         'rev_sha1',
 319                 ];
 320
 321                 $fields += CommentStore::newKey( 'rev_comment' )->getFields();
 322
 323                 if ( $wgContentHandlerUseDB ) {
 324                         $fields[] = 'rev_content_format';
 325                         $fields[] = 'rev_content_model';
 326                 }
 327
 328                 return $fields;
 329         }
 330
 331         /**
 332          * Return the list of revision fields that should be selected to create
 333          * a new revision from an archive row.
 334          * @deprecated since 1.31, use RevisionStore::getArchiveQueryInfo() instead.
 335          * @return array
 336          */
 337         public static function selectArchiveFields() {
 338                 global $wgContentHandlerUseDB;
 339
 340                 wfDeprecated( __METHOD__, '1.31' );
 341
 342                 $fields = [
 343                         'ar_id',
 344                         'ar_page_id',
 345                         'ar_rev_id',
 346                         'ar_text',
 347                         'ar_text_id',
 348                         'ar_timestamp',
 349                         'ar_user_text',
 350                         'ar_user',
 351                         'ar_minor_edit',
 352                         'ar_deleted',
 353                         'ar_len',
 354                         'ar_parent_id',
 355                         'ar_sha1',
 356                 ];
 357
 358                 $fields += CommentStore::newKey( 'ar_comment' )->getFields();
 359
 360                 if ( $wgContentHandlerUseDB ) {
 361                         $fields[] = 'ar_content_format';
 362                         $fields[] = 'ar_content_model';
 363                 }
 364                 return $fields;
 365         }
 366
 367         /**
 368          * Return the list of text fields that should be selected to read the
 369          * revision text
 370          * @deprecated since 1.31, use RevisionStore::getQueryInfo( [ 'text' ] ) instead.
 371          * @return array
 372          */
 373         public static function selectTextFields() {
 374                 wfDeprecated( __METHOD__, '1.31' );
 375                 return [
 376                         'old_text',
 377                         'old_flags'
 378                 ];
 379         }
 380
 381         /**
 382          * Return the list of page fields that should be selected from page table
 383          * @deprecated since 1.31, use RevisionStore::getQueryInfo( [ 'page' ] ) instead.
 384          * @return array
 385          */
 386         public static function selectPageFields() {
 387                 wfDeprecated( __METHOD__, '1.31' );
 388                 return [
 389                         'page_namespace',
 390                         'page_title',
 391                         'page_id',
 392                         'page_latest',
 393                         'page_is_redirect',
 394                         'page_len',
 395                 ];
 396         }
 397
 398         /**
 399          * Return the list of user fields that should be selected from user table
 400          * @deprecated since 1.31, use RevisionStore::getQueryInfo( [ 'user' ] ) instead.
 401          * @return array
 402          */
 403         public static function selectUserFields() {
 404                 wfDeprecated( __METHOD__, '1.31' );
 405                 return [ 'user_name' ];
 406         }
 407
 408         /**
 409          * Return the tables, fields, and join conditions to be selected to create
 410          * a new revision object.
 411          * @since 1.31
 412          * @deprecated since 1.31, use RevisionStore::getQueryInfo() instead.
 413          * @param array $options Any combination of the following strings
 414          *  - 'page': Join with the page table, and select fields to identify the page
 415          *  - 'user': Join with the user table, and select the user name
 416          *  - 'text': Join with the text table, and select fields to load page text
 417          * @return array With three keys:
 418          *   - tables: (string[]) to include in the `$table` to `IDatabase->select()`
 419          *   - fields: (string[]) to include in the `$vars` to `IDatabase->select()`
 420          *   - joins: (array) to include in the `$join_conds` to `IDatabase->select()`
 421          */
 422         public static function getQueryInfo( $options = [] ) {
 423                 return self::getRevisionStore()->getQueryInfo( $options );
 424         }
 425
 426         /**
 427          * Return the tables, fields, and join conditions to be selected to create
 428          * a new archived revision object.
 429          * @since 1.31
 430          * @deprecated since 1.31, use RevisionStore::getArchiveQueryInfo() instead.
 431          * @return array With three keys:
 432          *   - tables: (string[]) to include in the `$table` to `IDatabase->select()`
 433          *   - fields: (string[]) to include in the `$vars` to `IDatabase->select()`
 434          *   - joins: (array) to include in the `$join_conds` to `IDatabase->select()`
 435          */
 436         public static function getArchiveQueryInfo() {
 437                 return self::getRevisionStore()->getArchiveQueryInfo();
 438         }
 439
 440         /**
 441          * Do a batched query to get the parent revision lengths
 442          * @param IDatabase $db
 443          * @param array $revIds
 444          * @return array
 445          */
 446         public static function getParentLengths( $db, array $revIds ) {
 447                 return self::getRevisionStore()->listRevisionSizes( $db, $revIds );
 448         }
 449
 450         /**
 451          * @param object|array|RevisionRecord $row Either a database row or an array
 452          * @param int $queryFlags
 453          * @param Title|null $title
 454          *
 455          * @access private
 456          */
 457         function __construct( $row, $queryFlags = 0, Title $title = null ) {
 458                 global $wgUser;
 459
 460                 if ( $row instanceof RevisionRecord ) {
 461                         $this->mRecord = $row;
 462                 } elseif ( is_array( $row ) ) {
 463                         if ( !isset( $row['user'] ) && !isset( $row['user_text'] ) ) {
 464                                 $row['user'] = $wgUser;
 465                         }
 466
 467                         $this->mRecord = self::getRevisionStore()->newMutableRevisionFromArray(
 468                                 $row,
 469                                 $queryFlags,
 470                                 $title
 471                         );
 472                 } elseif ( is_object( $row ) ) {
 473                         $this->mRecord = self::getRevisionStore()->newRevisionFromRow(
 474                                 $row,
 475                                 $queryFlags,
 476                                 $title
 477                         );
 478                 } else {
 479                         throw new InvalidArgumentException(
 480                                 '$row must be a row object, an associative array, or a RevisionRecord'
 481                         );
 482                 }
 483         }
 484
 485         /**
 486          * @return RevisionRecord
 487          */
 488         public function getRevisionRecord() {
 489                 return $this->mRecord;
 490         }
 491
 492         /**
 493          * Get revision ID
 494          *
 495          * @return int|null
 496          */
 497         public function getId() {
 498                 return $this->mRecord->getId();
 499         }
 500
 501         /**
 502          * Set the revision ID
 503          *
 504          * This should only be used for proposed revisions that turn out to be null edits.
 505          *
 506          * @note Only supported on Revisions that were constructed based on associative arrays,
 507          *       since they are mutable.
 508          *
 509          * @since 1.19
 510          * @param int|string $id
 511          * @throws MWException
 512          */
 513         public function setId( $id ) {
 514                 if ( $this->mRecord instanceof MutableRevisionRecord ) {
 515                         $this->mRecord->setId( intval( $id ) );
 516                 } else {
 517                         throw new MWException( __METHOD__ . ' is not supported on this instance' );
 518                 }
 519         }
 520
 521         /**
 522          * Set the user ID/name
 523          *
 524          * This should only be used for proposed revisions that turn out to be null edits
 525          *
 526          * @note Only supported on Revisions that were constructed based on associative arrays,
 527          *       since they are mutable.
 528          *
 529          * @since 1.28
 530          * @deprecated since 1.31, please reuse old Revision object
 531          * @param int $id User ID
 532          * @param string $name User name
 533          * @throws MWException
 534          */
 535         public function setUserIdAndName( $id, $name ) {
 536                 if ( $this->mRecord instanceof MutableRevisionRecord ) {
 537                         $user = new UserIdentityValue( intval( $id ), $name );
 538                         $this->mRecord->setUser( $user );
 539                 } else {
 540                         throw new MWException( __METHOD__ . ' is not supported on this instance' );
 541                 }
 542         }
 543
 544         /**
 545          * @return SlotRecord
 546          */
 547         private function getMainSlotRaw() {
 548                 return $this->mRecord->getSlot( 'main', RevisionRecord::RAW );
 549         }
 550
 551         /**
 552          * Get the ID of the row of the text table that contains the content of the
 553          * revision's main slot, if that content is stored in the text table.
 554          *
 555          * If the content is stored elsewhere, this returns null.
 556          *
 557          * @deprecated since 1.31, use RevisionRecord()->getSlot()->getContentAddress() to
 558          * get that actual address that can be used with BlobStore::getBlob(); or use
 559          * RevisionRecord::hasSameContent() to check if two revisions have the same content.
 560          *
 561          * @return int|null
 562          */
 563         public function getTextId() {
 564                 $slot = $this->getMainSlotRaw();
 565                 return $slot->hasAddress()
 566                         ? self::getBlobStore()->getTextIdFromAddress( $slot->getAddress() )
 567                         : null;
 568         }
 569
 570         /**
 571          * Get parent revision ID (the original previous page revision)
 572          *
 573          * @return int|null The ID of the parent revision. 0 indicates that there is no
 574          * parent revision. Null indicates that the parent revision is not known.
 575          */
 576         public function getParentId() {
 577                 return $this->mRecord->getParentId();
 578         }
 579
 580         /**
 581          * Returns the length of the text in this revision, or null if unknown.
 582          *
 583          * @return int
 584          */
 585         public function getSize() {
 586                 return $this->mRecord->getSize();
 587         }
 588
 589         /**
 590          * Returns the base36 sha1 of the content in this revision, or null if unknown.
 591          *
 592          * @return string
 593          */
 594         public function getSha1() {
 595                 // XXX: we may want to drop all the hashing logic, it's not worth the overhead.
 596                 return $this->mRecord->getSha1();
 597         }
 598
 599         /**
 600          * Returns the title of the page associated with this entry.
 601          * Since 1.31, this will never return null.
 602          *
 603          * Will do a query, when title is not set and id is given.
 604          *
 605          * @return Title
 606          */
 607         public function getTitle() {
 608                 $linkTarget = $this->mRecord->getPageAsLinkTarget();
 609                 return Title::newFromLinkTarget( $linkTarget );
 610         }
 611
 612         /**
 613          * Set the title of the revision
 614          *
 615          * @deprecated: since 1.31, this is now a noop. Pass the Title to the constructor instead.
 616          *
 617          * @param Title $title
 618          */
 619         public function setTitle( $title ) {
 620                 if ( !$title->equals( $this->getTitle() ) ) {
 621                         throw new InvalidArgumentException(
 622                                 $title->getPrefixedText()
 623                                         . ' is not the same as '
 624                                         . $this->mRecord->getPageAsLinkTarget()->__toString()
 625                         );
 626                 }
 627         }
 628
 629         /**
 630          * Get the page ID
 631          *
 632          * @return int|null
 633          */
 634         public function getPage() {
 635                 return $this->mRecord->getPageId();
 636         }
 637
 638         /**
 639          * Fetch revision's user id if it's available to the specified audience.
 640          * If the specified audience does not have access to it, zero will be
 641          * returned.
 642          *
 643          * @param int $audience One of:
 644          *   Revision::FOR_PUBLIC       to be displayed to all users
 645          *   Revision::FOR_THIS_USER    to be displayed to the given user
 646          *   Revision::RAW              get the ID regardless of permissions
 647          * @param User|null $user User object to check for, only if FOR_THIS_USER is passed
 648          *   to the $audience parameter
 649          * @return int
 650          */
 651         public function getUser( $audience = self::FOR_PUBLIC, User $user = null ) {
 652                 global $wgUser;
 653
 654                 if ( $audience === self::FOR_THIS_USER && !$user ) {
 655                         $user = $wgUser;
 656                 }
 657
 658                 $user = $this->mRecord->getUser( $audience, $user );
 659                 return $user ? $user->getId() : 0;
 660         }
 661
 662         /**
 663          * Fetch revision's user id without regard for the current user's permissions
 664          *
 665          * @return int
 666          * @deprecated since 1.25, use getUser( Revision::RAW )
 667          */
 668         public function getRawUser() {
 669                 wfDeprecated( __METHOD__, '1.25' );
 670                 return $this->getUser( self::RAW );
 671         }
 672
 673         /**
 674          * Fetch revision's username if it's available to the specified audience.
 675          * If the specified audience does not have access to the username, an
 676          * empty string will be returned.
 677          *
 678          * @param int $audience One of:
 679          *   Revision::FOR_PUBLIC       to be displayed to all users
 680          *   Revision::FOR_THIS_USER    to be displayed to the given user
 681          *   Revision::RAW              get the text regardless of permissions
 682          * @param User|null $user User object to check for, only if FOR_THIS_USER is passed
 683          *   to the $audience parameter
 684          * @return string
 685          */
 686         public function getUserText( $audience = self::FOR_PUBLIC, User $user = null ) {
 687                 global $wgUser;
 688
 689                 if ( $audience === self::FOR_THIS_USER && !$user ) {
 690                         $user = $wgUser;
 691                 }
 692
 693                 $user = $this->mRecord->getUser( $audience, $user );
 694                 return $user ? $user->getName() : '';
 695         }
 696
 697         /**
 698          * Fetch revision's username without regard for view restrictions
 699          *
 700          * @return string
 701          * @deprecated since 1.25, use getUserText( Revision::RAW )
 702          */
 703         public function getRawUserText() {
 704                 wfDeprecated( __METHOD__, '1.25' );
 705                 return $this->getUserText( self::RAW );
 706         }
 707
 708         /**
 709          * Fetch revision comment if it's available to the specified audience.
 710          * If the specified audience does not have access to the comment, an
 711          * empty string will be returned.
 712          *
 713          * @param int $audience One of:
 714          *   Revision::FOR_PUBLIC       to be displayed to all users
 715          *   Revision::FOR_THIS_USER    to be displayed to the given user
 716          *   Revision::RAW              get the text regardless of permissions
 717          * @param User|null $user User object to check for, only if FOR_THIS_USER is passed
 718          *   to the $audience parameter
 719          * @return string
 720          */
 721         function getComment( $audience = self::FOR_PUBLIC, User $user = null ) {
 722                 global $wgUser;
 723
 724                 if ( $audience === self::FOR_THIS_USER && !$user ) {
 725                         $user = $wgUser;
 726                 }
 727
 728                 $comment = $this->mRecord->getComment( $audience, $user );
 729                 return $comment === null ? null : $comment->text;
 730         }
 731
 732         /**
 733          * Fetch revision comment without regard for the current user's permissions
 734          *
 735          * @return string
 736          * @deprecated since 1.25, use getComment( Revision::RAW )
 737          */
 738         public function getRawComment() {
 739                 wfDeprecated( __METHOD__, '1.25' );
 740                 return $this->getComment( self::RAW );
 741         }
 742
 743         /**
 744          * @return bool
 745          */
 746         public function isMinor() {
 747                 return $this->mRecord->isMinor();
 748         }
 749
 750         /**
 751          * @return int Rcid of the unpatrolled row, zero if there isn't one
 752          */
 753         public function isUnpatrolled() {
 754                 return self::getRevisionStore()->isUnpatrolled( $this->mRecord );
 755         }
 756
 757         /**
 758          * Get the RC object belonging to the current revision, if there's one
 759          *
 760          * @param int $flags (optional) $flags include:
 761          *      Revision::READ_LATEST  : Select the data from the master
 762          *
 763          * @since 1.22
 764          * @return RecentChange|null
 765          */
 766         public function getRecentChange( $flags = 0 ) {
 767                 return self::getRevisionStore()->getRecentChange( $this->mRecord, $flags );
 768         }
 769
 770         /**
 771          * @param int $field One of DELETED_* bitfield constants
 772          *
 773          * @return bool
 774          */
 775         public function isDeleted( $field ) {
 776                 return $this->mRecord->isDeleted( $field );
 777         }
 778
 779         /**
 780          * Get the deletion bitfield of the revision
 781          *
 782          * @return int
 783          */
 784         public function getVisibility() {
 785                 return $this->mRecord->getVisibility();
 786         }
 787
 788         /**
 789          * Fetch revision content if it's available to the specified audience.
 790          * If the specified audience does not have the ability to view this
 791          * revision, or the content could not be loaded, null will be returned.
 792          *
 793          * @param int $audience One of:
 794          *   Revision::FOR_PUBLIC       to be displayed to all users
 795          *   Revision::FOR_THIS_USER    to be displayed to $user
 796          *   Revision::RAW              get the text regardless of permissions
 797          * @param User $user User object to check for, only if FOR_THIS_USER is passed
 798          *   to the $audience parameter
 799          * @since 1.21
 800          * @return Content|null
 801          */
 802         public function getContent( $audience = self::FOR_PUBLIC, User $user = null ) {
 803                 global $wgUser;
 804
 805                 if ( $audience === self::FOR_THIS_USER && !$user ) {
 806                         $user = $wgUser;
 807                 }
 808
 809                 try {
 810                         return $this->mRecord->getContent( 'main', $audience, $user );
 811                 }
 812                 catch ( RevisionAccessException $e ) {
 813                         return null;
 814                 }
 815         }
 816
 817         /**
 818          * Get original serialized data (without checking view restrictions)
 819          *
 820          * @since 1.21
 821          * @deprecated since 1.31, use BlobStore::getBlob instead.
 822          *
 823          * @return string
 824          */
 825         public function getSerializedData() {
 826                 $slot = $this->getMainSlotRaw();
 827                 return $slot->getContent()->serialize();
 828         }
 829
 830         /**
 831          * Returns the content model for the main slot of this revision.
 832          *
 833          * If no content model was stored in the database, the default content model for the title is
 834          * used to determine the content model to use. If no title is know, CONTENT_MODEL_WIKITEXT
 835          * is used as a last resort.
 836          *
 837          * @todo: drop this, with MCR, there no longer is a single model associated with a revision.
 838          *
 839          * @return string The content model id associated with this revision,
 840          *     see the CONTENT_MODEL_XXX constants.
 841          */
 842         public function getContentModel() {
 843                 return $this->getMainSlotRaw()->getModel();
 844         }
 845
 846         /**
 847          * Returns the content format for the main slot of this revision.
 848          *
 849          * If no content format was stored in the database, the default format for this
 850          * revision's content model is returned.
 851          *
 852          * @todo: drop this, the format is irrelevant to the revision!
 853          *
 854          * @return string The content format id associated with this revision,
 855          *     see the CONTENT_FORMAT_XXX constants.
 856          */
 857         public function getContentFormat() {
 858                 $format = $this->getMainSlotRaw()->getFormat();
 859
 860                 if ( $format === null ) {
 861                         // if no format was stored along with the blob, fall back to default format
 862                         $format = $this->getContentHandler()->getDefaultFormat();
 863                 }
 864
 865                 return $format;
 866         }
 867
 868         /**
 869          * Returns the content handler appropriate for this revision's content model.
 870          *
 871          * @throws MWException
 872          * @return ContentHandler
 873          */
 874         public function getContentHandler() {
 875                 return ContentHandler::getForModelID( $this->getContentModel() );
 876         }
 877
 878         /**
 879          * @return string
 880          */
 881         public function getTimestamp() {
 882                 return $this->mRecord->getTimestamp();
 883         }
 884
 885         /**
 886          * @return bool
 887          */
 888         public function isCurrent() {
 889                 return ( $this->mRecord instanceof RevisionStoreRecord ) && $this->mRecord->isCurrent();
 890         }
 891
 892         /**
 893          * Get previous revision for this title
 894          *
 895          * @return Revision|null
 896          */
 897         public function getPrevious() {
 898                 $rec = self::getRevisionStore()->getPreviousRevision( $this->mRecord, $this->getTitle() );
 899                 return $rec === null
 900                         ? null
 901                         : new Revision( $rec, self::READ_NORMAL, $this->getTitle() );
 902         }
 903
 904         /**
 905          * Get next revision for this title
 906          *
 907          * @return Revision|null
 908          */
 909         public function getNext() {
 910                 $rec = self::getRevisionStore()->getNextRevision( $this->mRecord, $this->getTitle() );
 911                 return $rec === null
 912                         ? null
 913                         : new Revision( $rec, self::READ_NORMAL, $this->getTitle() );
 914         }
 915
 916         /**
 917          * Get revision text associated with an old or archive row
 918          *
 919          * Both the flags and the text field must be included. Including the old_id
 920          * field will activate cache usage as long as the $wiki parameter is not set.
 921          *
 922          * @param stdClass $row The text data
 923          * @param string $prefix Table prefix (default 'old_')
 924          * @param string|bool $wiki The name of the wiki to load the revision text from
 925          *   (same as the the wiki $row was loaded from) or false to indicate the local
 926          *   wiki (this is the default). Otherwise, it must be a symbolic wiki database
 927          *   identifier as understood by the LoadBalancer class.
 928          * @return string|false Text the text requested or false on failure
 929          */
 930         public static function getRevisionText( $row, $prefix = 'old_', $wiki = false ) {
 931                 $textField = $prefix . 'text';
 932                 $flagsField = $prefix . 'flags';
 933
 934                 if ( isset( $row->$flagsField ) ) {
 935                         $flags = explode( ',', $row->$flagsField );
 936                 } else {
 937                         $flags = [];
 938                 }
 939
 940                 if ( isset( $row->$textField ) ) {
 941                         $text = $row->$textField;
 942                 } else {
 943                         return false;
 944                 }
 945
 946                 $cacheKey = isset( $row->old_id ) ? ( 'tt:' . $row->old_id ) : null;
 947
 948                 return self::getBlobStore( $wiki )->expandBlob( $text, $flags, $cacheKey );
 949         }
 950
 951         /**
 952          * If $wgCompressRevisions is enabled, we will compress data.
 953          * The input string is modified in place.
 954          * Return value is the flags field: contains 'gzip' if the
 955          * data is compressed, and 'utf-8' if we're saving in UTF-8
 956          * mode.
 957          *
 958          * @param mixed &$text Reference to a text
 959          * @return string
 960          */
 961         public static function compressRevisionText( &$text ) {
 962                 return self::getBlobStore()->compressData( $text );
 963         }
 964
 965         /**
 966          * Re-converts revision text according to it's flags.
 967          *
 968          * @param mixed $text Reference to a text
 969          * @param array $flags Compression flags
 970          * @return string|bool Decompressed text, or false on failure
 971          */
 972         public static function decompressRevisionText( $text, $flags ) {
 973                 return self::getBlobStore()->decompressData( $text, $flags );
 974         }
 975
 976         /**
 977          * Insert a new revision into the database, returning the new revision ID
 978          * number on success and dies horribly on failure.
 979          *
 980          * @param IDatabase $dbw (master connection)
 981          * @throws MWException
 982          * @return int The revision ID
 983          */
 984         public function insertOn( $dbw ) {
 985                 global $wgUser;
 986
 987                 // Note that $this->mRecord->getId() will typically return null here, but not always,
 988                 // e.g. not when restoring a revision.
 989
 990                 if ( $this->mRecord->getUser( RevisionRecord::RAW ) === null ) {
 991                         if ( $this->mRecord instanceof MutableRevisionRecord ) {
 992                                 $this->mRecord->setUser( $wgUser );
 993                         } else {
 994                                 throw new MWException( 'Cannot insert revision with no associated user.' );
 995                         }
 996                 }
 997
 998                 $rec = self::getRevisionStore()->insertRevisionOn( $this->mRecord, $dbw );
 999
1000                 $this->mRecord = $rec;
1001
1002                 // Avoid PHP 7.1 warning of passing $this by reference
1003                 $revision = $this;
1004                 // TODO: hard-deprecate in 1.32 (or even 1.31?)
1005                 Hooks::run( 'RevisionInsertComplete', [ &$revision, null, null ] );
1006
1007                 return $rec->getId();
1008         }
1009
1010         /**
1011          * Get the base 36 SHA-1 value for a string of text
1012          * @param string $text
1013          * @return string
1014          */
1015         public static function base36Sha1( $text ) {
1016                 return SlotRecord::base36Sha1( $text );
1017         }
1018
1019         /**
1020          * Create a new null-revision for insertion into a page's
1021          * history. This will not re-save the text, but simply refer
1022          * to the text from the previous version.
1023          *
1024          * Such revisions can for instance identify page rename
1025          * operations and other such meta-modifications.
1026          *
1027          * @param IDatabase $dbw
1028          * @param int $pageId ID number of the page to read from
1029          * @param string $summary Revision's summary
1030          * @param bool $minor Whether the revision should be considered as minor
1031          * @param User|null $user User object to use or null for $wgUser
1032          * @return Revision|null Revision or null on error
1033          */
1034         public static function newNullRevision( $dbw, $pageId, $summary, $minor, $user = null ) {
1035                 global $wgUser;
1036                 if ( !$user ) {
1037                         $user = $wgUser;
1038                 }
1039
1040                 $comment = CommentStoreComment::newUnsavedComment( $summary, null );
1041
1042                 $title = Title::newFromID( $pageId );
1043                 $rec = self::getRevisionStore()->newNullRevision( $dbw, $title, $comment, $minor, $user );
1044
1045                 return new Revision( $rec );
1046         }
1047
1048         /**
1049          * Determine if the current user is allowed to view a particular
1050          * field of this revision, if it's marked as deleted.
1051          *
1052          * @param int $field One of self::DELETED_TEXT,
1053          *                              self::DELETED_COMMENT,
1054          *                              self::DELETED_USER
1055          * @param User|null $user User object to check, or null to use $wgUser
1056          * @return bool
1057          */
1058         public function userCan( $field, User $user = null ) {
1059                 return self::userCanBitfield( $this->getVisibility(), $field, $user );
1060         }
1061
1062         /**
1063          * Determine if the current user is allowed to view a particular
1064          * field of this revision, if it's marked as deleted. This is used
1065          * by various classes to avoid duplication.
1066          *
1067          * @param int $bitfield Current field
1068          * @param int $field One of self::DELETED_TEXT = File::DELETED_FILE,
1069          *                               self::DELETED_COMMENT = File::DELETED_COMMENT,
1070          *                               self::DELETED_USER = File::DELETED_USER
1071          * @param User|null $user User object to check, or null to use $wgUser
1072          * @param Title|null $title A Title object to check for per-page restrictions on,
1073          *                          instead of just plain userrights
1074          * @return bool
1075          */
1076         public static function userCanBitfield( $bitfield, $field, User $user = null,
1077                 Title $title = null
1078         ) {
1079                 global $wgUser;
1080
1081                 if ( !$user ) {
1082                         $user = $wgUser;
1083                 }
1084
1085                 return RevisionRecord::userCanBitfield( $bitfield, $field, $user, $title );
1086         }
1087
1088         /**
1089          * Get rev_timestamp from rev_id, without loading the rest of the row
1090          *
1091          * @param Title $title
1092          * @param int $id
1093          * @param int $flags
1094          * @return string|bool False if not found
1095          */
1096         static function getTimestampFromId( $title, $id, $flags = 0 ) {
1097                 return self::getRevisionStore()->getTimestampFromId( $title, $id, $flags );
1098         }
1099
1100         /**
1101          * Get count of revisions per page...not very efficient
1102          *
1103          * @param IDatabase $db
1104          * @param int $id Page id
1105          * @return int
1106          */
1107         static function countByPageId( $db, $id ) {
1108                 return self::getRevisionStore()->countRevisionsByPageId( $db, $id );
1109         }
1110
1111         /**
1112          * Get count of revisions per page...not very efficient
1113          *
1114          * @param IDatabase $db
1115          * @param Title $title
1116          * @return int
1117          */
1118         static function countByTitle( $db, $title ) {
1119                 return self::getRevisionStore()->countRevisionsByTitle( $db, $title );
1120         }
1121
1122         /**
1123          * Check if no edits were made by other users since
1124          * the time a user started editing the page. Limit to
1125          * 50 revisions for the sake of performance.
1126          *
1127          * @since 1.20
1128          * @deprecated since 1.24
1129          *
1130          * @param IDatabase|int $db The Database to perform the check on. May be given as a
1131          *        Database object or a database identifier usable with wfGetDB.
1132          * @param int $pageId The ID of the page in question
1133          * @param int $userId The ID of the user in question
1134          * @param string $since Look at edits since this time
1135          *
1136          * @return bool True if the given user was the only one to edit since the given timestamp
1137          */
1138         public static function userWasLastToEdit( $db, $pageId, $userId, $since ) {
1139                 if ( is_int( $db ) ) {
1140                         $db = wfGetDB( $db );
1141                 }
1142
1143                 return self::getRevisionStore()->userWasLastToEdit( $db, $pageId, $userId, $since );
1144         }
1145
1146         /**
1147          * Load a revision based on a known page ID and current revision ID from the DB
1148          *
1149          * This method allows for the use of caching, though accessing anything that normally
1150          * requires permission checks (aside from the text) will trigger a small DB lookup.
1151          * The title will also be loaded if $pageIdOrTitle is an integer ID.
1152          *
1153          * @param IDatabase $db ignored!
1154          * @param int|Title $pageIdOrTitle Page ID or Title object
1155          * @param int $revId Known current revision of this page. Determined automatically if not given.
1156          * @return Revision|bool Returns false if missing
1157          * @since 1.28
1158          */
1159         public static function newKnownCurrent( IDatabase $db, $pageIdOrTitle, $revId = 0 ) {
1160                 $title = $pageIdOrTitle instanceof Title
1161                         ? $pageIdOrTitle
1162                         : Title::newFromID( $pageIdOrTitle );
1163
1164                 $record = self::getRevisionStore()->getKnownCurrentRevision( $title, $revId );
1165                 return $record ? new Revision( $record ) : false;
1166         }
1167 }