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 $wiki 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          *
 149          * @throws MWException
 150          * @return Revision
 151          */
 152         public static function newFromArchiveRow( $row, $overrides = [] ) {
 153                 /**
 154                  * MCR Migration: https://phabricator.wikimedia.org/T183564
 155                  * This method used to overwrite attributes, then passed to Revision::__construct
 156                  * RevisionStore::newRevisionFromArchiveRow instead overrides row field names
 157                  * So do a conversion here.
 158                  */
 159                 if ( array_key_exists( 'page', $overrides ) ) {
 160                         $overrides['page_id'] = $overrides['page'];
 161                         unset( $overrides['page'] );
 162                 }
 163
 164                 /**
 165                  * We require a Title for both the Revision object and the RevisionRecord.
 166                  * Below is duplicated logic from RevisionStore::newRevisionFromArchiveRow
 167                  * to fetch a title in order pass it into the Revision object.
 168                  */
 169                 $title = null;
 170                 if ( isset( $overrides['title'] ) ) {
 171                         if ( !( $overrides['title'] instanceof Title ) ) {
 172                                 throw new MWException( 'title field override must contain a Title object.' );
 173                         }
 174
 175                         $title = $overrides['title'];
 176                 }
 177                 if ( $title !== null ) {
 178                         if ( isset( $row->ar_namespace ) && isset( $row->ar_title ) ) {
 179                                 $title = Title::makeTitle( $row->ar_namespace, $row->ar_title );
 180                         } else {
 181                                 throw new InvalidArgumentException(
 182                                         'A Title or ar_namespace and ar_title must be given'
 183                                 );
 184                         }
 185                 }
 186
 187                 $rec = self::getRevisionStore()->newRevisionFromArchiveRow( $row, 0, $title, $overrides );
 188                 return new Revision( $rec, self::READ_NORMAL, $title );
 189         }
 190
 191         /**
 192          * @since 1.19
 193          *
 194          * MCR migration note: replaced by RevisionStore::newRevisionFromRow(). Note that
 195          * newFromRow() also accepts arrays, while newRevisionFromRow() does not. Instead,
 196          * a MutableRevisionRecord should be constructed directly.
 197          * RevisionStore::newMutableRevisionFromArray() can be used as a temporary replacement,
 198          * but should be avoided.
 199          *
 200          * @param object|array $row
 201          * @return Revision
 202          */
 203         public static function newFromRow( $row ) {
 204                 if ( is_array( $row ) ) {
 205                         $rec = self::getRevisionStore()->newMutableRevisionFromArray( $row );
 206                 } else {
 207                         $rec = self::getRevisionStore()->newRevisionFromRow( $row );
 208                 }
 209
 210                 return new Revision( $rec );
 211         }
 212
 213         /**
 214          * Load a page revision from a given revision ID number.
 215          * Returns null if no such revision can be found.
 216          *
 217          * @deprecated since 1.31, use RevisionStore::getRevisionById() instead.
 218          *
 219          * @param IDatabase $db
 220          * @param int $id
 221          * @return Revision|null
 222          */
 223         public static function loadFromId( $db, $id ) {
 224                 wfDeprecated( __METHOD__, '1.31' ); // no known callers
 225                 $rec = self::getRevisionStore()->loadRevisionFromId( $db, $id );
 226                 return $rec === null ? null : new Revision( $rec );
 227         }
 228
 229         /**
 230          * Load either the current, or a specified, revision
 231          * that's attached to a given page. If not attached
 232          * to that page, will return null.
 233          *
 234          * @deprecated since 1.31, use RevisionStore::getRevisionByPageId() instead.
 235          *
 236          * @param IDatabase $db
 237          * @param int $pageid
 238          * @param int $id
 239          * @return Revision|null
 240          */
 241         public static function loadFromPageId( $db, $pageid, $id = 0 ) {
 242                 $rec = self::getRevisionStore()->loadRevisionFromPageId( $db, $pageid, $id );
 243                 return $rec === null ? null : new Revision( $rec );
 244         }
 245
 246         /**
 247          * Load either the current, or a specified, revision
 248          * that's attached to a given page. If not attached
 249          * to that page, will return null.
 250          *
 251          * @deprecated since 1.31, use RevisionStore::getRevisionByTitle() instead.
 252          *
 253          * @param IDatabase $db
 254          * @param Title $title
 255          * @param int $id
 256          * @return Revision|null
 257          */
 258         public static function loadFromTitle( $db, $title, $id = 0 ) {
 259                 $rec = self::getRevisionStore()->loadRevisionFromTitle( $db, $title, $id );
 260                 return $rec === null ? null : new Revision( $rec );
 261         }
 262
 263         /**
 264          * Load the revision for the given title with the given timestamp.
 265          * WARNING: Timestamps may in some circumstances not be unique,
 266          * so this isn't the best key to use.
 267          *
 268          * @deprecated since 1.31, use RevisionStore::getRevisionByTimestamp()
 269          *   or RevisionStore::loadRevisionFromTimestamp() instead.
 270          *
 271          * @param IDatabase $db
 272          * @param Title $title
 273          * @param string $timestamp
 274          * @return Revision|null
 275          */
 276         public static function loadFromTimestamp( $db, $title, $timestamp ) {
 277                 $rec = self::getRevisionStore()->loadRevisionFromTimestamp( $db, $title, $timestamp );
 278                 return $rec === null ? null : new Revision( $rec );
 279         }
 280
 281         /**
 282          * Return a wrapper for a series of database rows to
 283          * fetch all of a given page's revisions in turn.
 284          * Each row can be fed to the constructor to get objects.
 285          *
 286          * @param LinkTarget $title
 287          * @return ResultWrapper
 288          * @deprecated Since 1.28, no callers in core nor in known extensions. No-op since 1.31.
 289          */
 290         public static function fetchRevision( LinkTarget $title ) {
 291                 wfDeprecated( __METHOD__, '1.31' );
 292                 return new FakeResultWrapper( [] );
 293         }
 294
 295         /**
 296          * Return the value of a select() JOIN conds array for the user table.
 297          * This will get user table rows for logged-in users.
 298          * @since 1.19
 299          * @deprecated since 1.31, use RevisionStore::getQueryInfo( [ 'user' ] ) instead.
 300          * @return array
 301          */
 302         public static function userJoinCond() {
 303                 wfDeprecated( __METHOD__, '1.31' );
 304                 return [ 'LEFT JOIN', [ 'rev_user != 0', 'user_id = rev_user' ] ];
 305         }
 306
 307         /**
 308          * Return the value of a select() page conds array for the page table.
 309          * This will assure that the revision(s) are not orphaned from live pages.
 310          * @since 1.19
 311          * @deprecated since 1.31, use RevisionStore::getQueryInfo( [ 'page' ] ) instead.
 312          * @return array
 313          */
 314         public static function pageJoinCond() {
 315                 wfDeprecated( __METHOD__, '1.31' );
 316                 return [ 'INNER JOIN', [ 'page_id = rev_page' ] ];
 317         }
 318
 319         /**
 320          * Return the list of revision fields that should be selected to create
 321          * a new revision.
 322          * @deprecated since 1.31, use RevisionStore::getQueryInfo() instead.
 323          * @return array
 324          */
 325         public static function selectFields() {
 326                 global $wgContentHandlerUseDB;
 327
 328                 wfDeprecated( __METHOD__, '1.31' );
 329
 330                 $fields = [
 331                         'rev_id',
 332                         'rev_page',
 333                         'rev_text_id',
 334                         'rev_timestamp',
 335                         'rev_user_text',
 336                         'rev_user',
 337                         'rev_minor_edit',
 338                         'rev_deleted',
 339                         'rev_len',
 340                         'rev_parent_id',
 341                         'rev_sha1',
 342                 ];
 343
 344                 $fields += CommentStore::newKey( 'rev_comment' )->getFields();
 345
 346                 if ( $wgContentHandlerUseDB ) {
 347                         $fields[] = 'rev_content_format';
 348                         $fields[] = 'rev_content_model';
 349                 }
 350
 351                 return $fields;
 352         }
 353
 354         /**
 355          * Return the list of revision fields that should be selected to create
 356          * a new revision from an archive row.
 357          * @deprecated since 1.31, use RevisionStore::getArchiveQueryInfo() instead.
 358          * @return array
 359          */
 360         public static function selectArchiveFields() {
 361                 global $wgContentHandlerUseDB;
 362
 363                 wfDeprecated( __METHOD__, '1.31' );
 364
 365                 $fields = [
 366                         'ar_id',
 367                         'ar_page_id',
 368                         'ar_rev_id',
 369                         'ar_text',
 370                         'ar_text_id',
 371                         'ar_timestamp',
 372                         'ar_user_text',
 373                         'ar_user',
 374                         'ar_minor_edit',
 375                         'ar_deleted',
 376                         'ar_len',
 377                         'ar_parent_id',
 378                         'ar_sha1',
 379                 ];
 380
 381                 $fields += CommentStore::newKey( 'ar_comment' )->getFields();
 382
 383                 if ( $wgContentHandlerUseDB ) {
 384                         $fields[] = 'ar_content_format';
 385                         $fields[] = 'ar_content_model';
 386                 }
 387                 return $fields;
 388         }
 389
 390         /**
 391          * Return the list of text fields that should be selected to read the
 392          * revision text
 393          * @deprecated since 1.31, use RevisionStore::getQueryInfo( [ 'text' ] ) instead.
 394          * @return array
 395          */
 396         public static function selectTextFields() {
 397                 wfDeprecated( __METHOD__, '1.31' );
 398                 return [
 399                         'old_text',
 400                         'old_flags'
 401                 ];
 402         }
 403
 404         /**
 405          * Return the list of page fields that should be selected from page table
 406          * @deprecated since 1.31, use RevisionStore::getQueryInfo( [ 'page' ] ) instead.
 407          * @return array
 408          */
 409         public static function selectPageFields() {
 410                 wfDeprecated( __METHOD__, '1.31' );
 411                 return [
 412                         'page_namespace',
 413                         'page_title',
 414                         'page_id',
 415                         'page_latest',
 416                         'page_is_redirect',
 417                         'page_len',
 418                 ];
 419         }
 420
 421         /**
 422          * Return the list of user fields that should be selected from user table
 423          * @deprecated since 1.31, use RevisionStore::getQueryInfo( [ 'user' ] ) instead.
 424          * @return array
 425          */
 426         public static function selectUserFields() {
 427                 wfDeprecated( __METHOD__, '1.31' );
 428                 return [ 'user_name' ];
 429         }
 430
 431         /**
 432          * Return the tables, fields, and join conditions to be selected to create
 433          * a new revision object.
 434          * @since 1.31
 435          * @deprecated since 1.31, use RevisionStore::getQueryInfo() instead.
 436          * @param array $options Any combination of the following strings
 437          *  - 'page': Join with the page table, and select fields to identify the page
 438          *  - 'user': Join with the user table, and select the user name
 439          *  - 'text': Join with the text table, and select fields to load page text
 440          * @return array With three keys:
 441          *   - tables: (string[]) to include in the `$table` to `IDatabase->select()`
 442          *   - fields: (string[]) to include in the `$vars` to `IDatabase->select()`
 443          *   - joins: (array) to include in the `$join_conds` to `IDatabase->select()`
 444          */
 445         public static function getQueryInfo( $options = [] ) {
 446                 return self::getRevisionStore()->getQueryInfo( $options );
 447         }
 448
 449         /**
 450          * Return the tables, fields, and join conditions to be selected to create
 451          * a new archived revision object.
 452          * @since 1.31
 453          * @deprecated since 1.31, use RevisionStore::getArchiveQueryInfo() instead.
 454          * @return array With three keys:
 455          *   - tables: (string[]) to include in the `$table` to `IDatabase->select()`
 456          *   - fields: (string[]) to include in the `$vars` to `IDatabase->select()`
 457          *   - joins: (array) to include in the `$join_conds` to `IDatabase->select()`
 458          */
 459         public static function getArchiveQueryInfo() {
 460                 return self::getRevisionStore()->getArchiveQueryInfo();
 461         }
 462
 463         /**
 464          * Do a batched query to get the parent revision lengths
 465          *
 466          * @deprecated in 1.31, use RevisionStore::getRevisionSizes instead.
 467          *
 468          * @param IDatabase $db
 469          * @param array $revIds
 470          * @return array
 471          */
 472         public static function getParentLengths( $db, array $revIds ) {
 473                 return self::getRevisionStore()->listRevisionSizes( $db, $revIds );
 474         }
 475
 476         /**
 477          * @param object|array|RevisionRecord $row Either a database row or an array
 478          * @param int $queryFlags
 479          * @param Title|null $title
 480          *
 481          * @access private
 482          */
 483         function __construct( $row, $queryFlags = 0, Title $title = null ) {
 484                 global $wgUser;
 485
 486                 if ( $row instanceof RevisionRecord ) {
 487                         $this->mRecord = $row;
 488                 } elseif ( is_array( $row ) ) {
 489                         // If no user is specified, fall back to using the global user object, to stay
 490                         // compatible with pre-1.31 behavior.
 491                         if ( !isset( $row['user'] ) && !isset( $row['user_text'] ) ) {
 492                                 $row['user'] = $wgUser;
 493                         }
 494
 495                         $this->mRecord = self::getRevisionStore()->newMutableRevisionFromArray(
 496                                 $row,
 497                                 $queryFlags,
 498                                 $title
 499                         );
 500                 } elseif ( is_object( $row ) ) {
 501                         $this->mRecord = self::getRevisionStore()->newRevisionFromRow(
 502                                 $row,
 503                                 $queryFlags,
 504                                 $title
 505                         );
 506                 } else {
 507                         throw new InvalidArgumentException(
 508                                 '$row must be a row object, an associative array, or a RevisionRecord'
 509                         );
 510                 }
 511         }
 512
 513         /**
 514          * @return RevisionRecord
 515          */
 516         public function getRevisionRecord() {
 517                 return $this->mRecord;
 518         }
 519
 520         /**
 521          * Get revision ID
 522          *
 523          * @return int|null
 524          */
 525         public function getId() {
 526                 return $this->mRecord->getId();
 527         }
 528
 529         /**
 530          * Set the revision ID
 531          *
 532          * This should only be used for proposed revisions that turn out to be null edits.
 533          *
 534          * @note Only supported on Revisions that were constructed based on associative arrays,
 535          *       since they are mutable.
 536          *
 537          * @since 1.19
 538          * @param int|string $id
 539          * @throws MWException
 540          */
 541         public function setId( $id ) {
 542                 if ( $this->mRecord instanceof MutableRevisionRecord ) {
 543                         $this->mRecord->setId( intval( $id ) );
 544                 } else {
 545                         throw new MWException( __METHOD__ . ' is not supported on this instance' );
 546                 }
 547         }
 548
 549         /**
 550          * Set the user ID/name
 551          *
 552          * This should only be used for proposed revisions that turn out to be null edits
 553          *
 554          * @note Only supported on Revisions that were constructed based on associative arrays,
 555          *       since they are mutable.
 556          *
 557          * @since 1.28
 558          * @deprecated since 1.31, please reuse old Revision object
 559          * @param int $id User ID
 560          * @param string $name User name
 561          * @throws MWException
 562          */
 563         public function setUserIdAndName( $id, $name ) {
 564                 if ( $this->mRecord instanceof MutableRevisionRecord ) {
 565                         $user = new UserIdentityValue( intval( $id ), $name );
 566                         $this->mRecord->setUser( $user );
 567                 } else {
 568                         throw new MWException( __METHOD__ . ' is not supported on this instance' );
 569                 }
 570         }
 571
 572         /**
 573          * @return SlotRecord
 574          */
 575         private function getMainSlotRaw() {
 576                 return $this->mRecord->getSlot( 'main', RevisionRecord::RAW );
 577         }
 578
 579         /**
 580          * Get the ID of the row of the text table that contains the content of the
 581          * revision's main slot, if that content is stored in the text table.
 582          *
 583          * If the content is stored elsewhere, this returns null.
 584          *
 585          * @deprecated since 1.31, use RevisionRecord()->getSlot()->getContentAddress() to
 586          * get that actual address that can be used with BlobStore::getBlob(); or use
 587          * RevisionRecord::hasSameContent() to check if two revisions have the same content.
 588          *
 589          * @return int|null
 590          */
 591         public function getTextId() {
 592                 $slot = $this->getMainSlotRaw();
 593                 return $slot->hasAddress()
 594                         ? self::getBlobStore()->getTextIdFromAddress( $slot->getAddress() )
 595                         : null;
 596         }
 597
 598         /**
 599          * Get parent revision ID (the original previous page revision)
 600          *
 601          * @return int|null The ID of the parent revision. 0 indicates that there is no
 602          * parent revision. Null indicates that the parent revision is not known.
 603          */
 604         public function getParentId() {
 605                 return $this->mRecord->getParentId();
 606         }
 607
 608         /**
 609          * Returns the length of the text in this revision, or null if unknown.
 610          *
 611          * @return int
 612          */
 613         public function getSize() {
 614                 return $this->mRecord->getSize();
 615         }
 616
 617         /**
 618          * Returns the base36 sha1 of the content in this revision, or null if unknown.
 619          *
 620          * @return string
 621          */
 622         public function getSha1() {
 623                 // XXX: we may want to drop all the hashing logic, it's not worth the overhead.
 624                 return $this->mRecord->getSha1();
 625         }
 626
 627         /**
 628          * Returns the title of the page associated with this entry.
 629          * Since 1.31, this will never return null.
 630          *
 631          * Will do a query, when title is not set and id is given.
 632          *
 633          * @return Title
 634          */
 635         public function getTitle() {
 636                 $linkTarget = $this->mRecord->getPageAsLinkTarget();
 637                 return Title::newFromLinkTarget( $linkTarget );
 638         }
 639
 640         /**
 641          * Set the title of the revision
 642          *
 643          * @deprecated: since 1.31, this is now a noop. Pass the Title to the constructor instead.
 644          *
 645          * @param Title $title
 646          */
 647         public function setTitle( $title ) {
 648                 if ( !$title->equals( $this->getTitle() ) ) {
 649                         throw new InvalidArgumentException(
 650                                 $title->getPrefixedText()
 651                                         . ' is not the same as '
 652                                         . $this->mRecord->getPageAsLinkTarget()->__toString()
 653                         );
 654                 }
 655         }
 656
 657         /**
 658          * Get the page ID
 659          *
 660          * @return int|null
 661          */
 662         public function getPage() {
 663                 return $this->mRecord->getPageId();
 664         }
 665
 666         /**
 667          * Fetch revision's user id if it's available to the specified audience.
 668          * If the specified audience does not have access to it, zero will be
 669          * returned.
 670          *
 671          * @param int $audience One of:
 672          *   Revision::FOR_PUBLIC       to be displayed to all users
 673          *   Revision::FOR_THIS_USER    to be displayed to the given user
 674          *   Revision::RAW              get the ID regardless of permissions
 675          * @param User|null $user User object to check for, only if FOR_THIS_USER is passed
 676          *   to the $audience parameter
 677          * @return int
 678          */
 679         public function getUser( $audience = self::FOR_PUBLIC, User $user = null ) {
 680                 global $wgUser;
 681
 682                 if ( $audience === self::FOR_THIS_USER && !$user ) {
 683                         $user = $wgUser;
 684                 }
 685
 686                 $user = $this->mRecord->getUser( $audience, $user );
 687                 return $user ? $user->getId() : 0;
 688         }
 689
 690         /**
 691          * Fetch revision's user id without regard for the current user's permissions
 692          *
 693          * @return int
 694          * @deprecated since 1.25, use getUser( Revision::RAW )
 695          */
 696         public function getRawUser() {
 697                 wfDeprecated( __METHOD__, '1.25' );
 698                 return $this->getUser( self::RAW );
 699         }
 700
 701         /**
 702          * Fetch revision's username if it's available to the specified audience.
 703          * If the specified audience does not have access to the username, an
 704          * empty string will be returned.
 705          *
 706          * @param int $audience One of:
 707          *   Revision::FOR_PUBLIC       to be displayed to all users
 708          *   Revision::FOR_THIS_USER    to be displayed to the given user
 709          *   Revision::RAW              get the text regardless of permissions
 710          * @param User|null $user User object to check for, only if FOR_THIS_USER is passed
 711          *   to the $audience parameter
 712          * @return string
 713          */
 714         public function getUserText( $audience = self::FOR_PUBLIC, User $user = null ) {
 715                 global $wgUser;
 716
 717                 if ( $audience === self::FOR_THIS_USER && !$user ) {
 718                         $user = $wgUser;
 719                 }
 720
 721                 $user = $this->mRecord->getUser( $audience, $user );
 722                 return $user ? $user->getName() : '';
 723         }
 724
 725         /**
 726          * Fetch revision's username without regard for view restrictions
 727          *
 728          * @return string
 729          * @deprecated since 1.25, use getUserText( Revision::RAW )
 730          */
 731         public function getRawUserText() {
 732                 wfDeprecated( __METHOD__, '1.25' );
 733                 return $this->getUserText( self::RAW );
 734         }
 735
 736         /**
 737          * Fetch revision comment if it's available to the specified audience.
 738          * If the specified audience does not have access to the comment, an
 739          * empty string will be returned.
 740          *
 741          * @param int $audience One of:
 742          *   Revision::FOR_PUBLIC       to be displayed to all users
 743          *   Revision::FOR_THIS_USER    to be displayed to the given user
 744          *   Revision::RAW              get the text regardless of permissions
 745          * @param User|null $user User object to check for, only if FOR_THIS_USER is passed
 746          *   to the $audience parameter
 747          * @return string
 748          */
 749         function getComment( $audience = self::FOR_PUBLIC, User $user = null ) {
 750                 global $wgUser;
 751
 752                 if ( $audience === self::FOR_THIS_USER && !$user ) {
 753                         $user = $wgUser;
 754                 }
 755
 756                 $comment = $this->mRecord->getComment( $audience, $user );
 757                 return $comment === null ? null : $comment->text;
 758         }
 759
 760         /**
 761          * Fetch revision comment without regard for the current user's permissions
 762          *
 763          * @return string
 764          * @deprecated since 1.25, use getComment( Revision::RAW )
 765          */
 766         public function getRawComment() {
 767                 wfDeprecated( __METHOD__, '1.25' );
 768                 return $this->getComment( self::RAW );
 769         }
 770
 771         /**
 772          * @return bool
 773          */
 774         public function isMinor() {
 775                 return $this->mRecord->isMinor();
 776         }
 777
 778         /**
 779          * @return int Rcid of the unpatrolled row, zero if there isn't one
 780          */
 781         public function isUnpatrolled() {
 782                 return self::getRevisionStore()->getRcIdIfUnpatrolled( $this->mRecord );
 783         }
 784
 785         /**
 786          * Get the RC object belonging to the current revision, if there's one
 787          *
 788          * @param int $flags (optional) $flags include:
 789          *      Revision::READ_LATEST  : Select the data from the master
 790          *
 791          * @since 1.22
 792          * @return RecentChange|null
 793          */
 794         public function getRecentChange( $flags = 0 ) {
 795                 return self::getRevisionStore()->getRecentChange( $this->mRecord, $flags );
 796         }
 797
 798         /**
 799          * @param int $field One of DELETED_* bitfield constants
 800          *
 801          * @return bool
 802          */
 803         public function isDeleted( $field ) {
 804                 return $this->mRecord->isDeleted( $field );
 805         }
 806
 807         /**
 808          * Get the deletion bitfield of the revision
 809          *
 810          * @return int
 811          */
 812         public function getVisibility() {
 813                 return $this->mRecord->getVisibility();
 814         }
 815
 816         /**
 817          * Fetch revision content if it's available to the specified audience.
 818          * If the specified audience does not have the ability to view this
 819          * revision, or the content could not be loaded, null will be returned.
 820          *
 821          * @param int $audience One of:
 822          *   Revision::FOR_PUBLIC       to be displayed to all users
 823          *   Revision::FOR_THIS_USER    to be displayed to $user
 824          *   Revision::RAW              get the text regardless of permissions
 825          * @param User $user User object to check for, only if FOR_THIS_USER is passed
 826          *   to the $audience parameter
 827          * @since 1.21
 828          * @return Content|null
 829          */
 830         public function getContent( $audience = self::FOR_PUBLIC, User $user = null ) {
 831                 global $wgUser;
 832
 833                 if ( $audience === self::FOR_THIS_USER && !$user ) {
 834                         $user = $wgUser;
 835                 }
 836
 837                 try {
 838                         return $this->mRecord->getContent( 'main', $audience, $user );
 839                 }
 840                 catch ( RevisionAccessException $e ) {
 841                         return null;
 842                 }
 843         }
 844
 845         /**
 846          * Get original serialized data (without checking view restrictions)
 847          *
 848          * @since 1.21
 849          * @deprecated since 1.31, use BlobStore::getBlob instead.
 850          *
 851          * @return string
 852          */
 853         public function getSerializedData() {
 854                 $slot = $this->getMainSlotRaw();
 855                 return $slot->getContent()->serialize();
 856         }
 857
 858         /**
 859          * Returns the content model for the main slot of this revision.
 860          *
 861          * If no content model was stored in the database, the default content model for the title is
 862          * used to determine the content model to use. If no title is know, CONTENT_MODEL_WIKITEXT
 863          * is used as a last resort.
 864          *
 865          * @todo: drop this, with MCR, there no longer is a single model associated with a revision.
 866          *
 867          * @return string The content model id associated with this revision,
 868          *     see the CONTENT_MODEL_XXX constants.
 869          */
 870         public function getContentModel() {
 871                 return $this->getMainSlotRaw()->getModel();
 872         }
 873
 874         /**
 875          * Returns the content format for the main slot of this revision.
 876          *
 877          * If no content format was stored in the database, the default format for this
 878          * revision's content model is returned.
 879          *
 880          * @todo: drop this, the format is irrelevant to the revision!
 881          *
 882          * @return string The content format id associated with this revision,
 883          *     see the CONTENT_FORMAT_XXX constants.
 884          */
 885         public function getContentFormat() {
 886                 $format = $this->getMainSlotRaw()->getFormat();
 887
 888                 if ( $format === null ) {
 889                         // if no format was stored along with the blob, fall back to default format
 890                         $format = $this->getContentHandler()->getDefaultFormat();
 891                 }
 892
 893                 return $format;
 894         }
 895
 896         /**
 897          * Returns the content handler appropriate for this revision's content model.
 898          *
 899          * @throws MWException
 900          * @return ContentHandler
 901          */
 902         public function getContentHandler() {
 903                 return ContentHandler::getForModelID( $this->getContentModel() );
 904         }
 905
 906         /**
 907          * @return string
 908          */
 909         public function getTimestamp() {
 910                 return $this->mRecord->getTimestamp();
 911         }
 912
 913         /**
 914          * @return bool
 915          */
 916         public function isCurrent() {
 917                 return ( $this->mRecord instanceof RevisionStoreRecord ) && $this->mRecord->isCurrent();
 918         }
 919
 920         /**
 921          * Get previous revision for this title
 922          *
 923          * @return Revision|null
 924          */
 925         public function getPrevious() {
 926                 $title = $this->getTitle();
 927                 $rec = self::getRevisionStore()->getPreviousRevision( $this->mRecord, $title );
 928                 return $rec === null ? null : new Revision( $rec, self::READ_NORMAL, $title );
 929         }
 930
 931         /**
 932          * Get next revision for this title
 933          *
 934          * @return Revision|null
 935          */
 936         public function getNext() {
 937                 $title = $this->getTitle();
 938                 $rec = self::getRevisionStore()->getNextRevision( $this->mRecord, $title );
 939                 return $rec === null ? null : new Revision( $rec, self::READ_NORMAL, $title );
 940         }
 941
 942         /**
 943          * Get revision text associated with an old or archive row
 944          *
 945          * Both the flags and the text field must be included. Including the old_id
 946          * field will activate cache usage as long as the $wiki parameter is not set.
 947          *
 948          * @param stdClass $row The text data
 949          * @param string $prefix Table prefix (default 'old_')
 950          * @param string|bool $wiki The name of the wiki to load the revision text from
 951          *   (same as the the wiki $row was loaded from) or false to indicate the local
 952          *   wiki (this is the default). Otherwise, it must be a symbolic wiki database
 953          *   identifier as understood by the LoadBalancer class.
 954          * @return string|false Text the text requested or false on failure
 955          */
 956         public static function getRevisionText( $row, $prefix = 'old_', $wiki = false ) {
 957                 $textField = $prefix . 'text';
 958                 $flagsField = $prefix . 'flags';
 959
 960                 if ( isset( $row->$flagsField ) ) {
 961                         $flags = explode( ',', $row->$flagsField );
 962                 } else {
 963                         $flags = [];
 964                 }
 965
 966                 if ( isset( $row->$textField ) ) {
 967                         $text = $row->$textField;
 968                 } else {
 969                         return false;
 970                 }
 971
 972                 $cacheKey = isset( $row->old_id ) ? ( 'tt:' . $row->old_id ) : null;
 973
 974                 return self::getBlobStore( $wiki )->expandBlob( $text, $flags, $cacheKey );
 975         }
 976
 977         /**
 978          * If $wgCompressRevisions is enabled, we will compress data.
 979          * The input string is modified in place.
 980          * Return value is the flags field: contains 'gzip' if the
 981          * data is compressed, and 'utf-8' if we're saving in UTF-8
 982          * mode.
 983          *
 984          * @param mixed &$text Reference to a text
 985          * @return string
 986          */
 987         public static function compressRevisionText( &$text ) {
 988                 return self::getBlobStore()->compressData( $text );
 989         }
 990
 991         /**
 992          * Re-converts revision text according to it's flags.
 993          *
 994          * @param mixed $text Reference to a text
 995          * @param array $flags Compression flags
 996          * @return string|bool Decompressed text, or false on failure
 997          */
 998         public static function decompressRevisionText( $text, $flags ) {
 999                 return self::getBlobStore()->decompressData( $text, $flags );
1000         }
1001
1002         /**
1003          * Insert a new revision into the database, returning the new revision ID
1004          * number on success and dies horribly on failure.
1005          *
1006          * @param IDatabase $dbw (master connection)
1007          * @throws MWException
1008          * @return int The revision ID
1009          */
1010         public function insertOn( $dbw ) {
1011                 global $wgUser;
1012
1013                 // Note that $this->mRecord->getId() will typically return null here, but not always,
1014                 // e.g. not when restoring a revision.
1015
1016                 if ( $this->mRecord->getUser( RevisionRecord::RAW ) === null ) {
1017                         if ( $this->mRecord instanceof MutableRevisionRecord ) {
1018                                 $this->mRecord->setUser( $wgUser );
1019                         } else {
1020                                 throw new MWException( 'Cannot insert revision with no associated user.' );
1021                         }
1022                 }
1023
1024                 $rec = self::getRevisionStore()->insertRevisionOn( $this->mRecord, $dbw );
1025
1026                 $this->mRecord = $rec;
1027
1028                 // Avoid PHP 7.1 warning of passing $this by reference
1029                 $revision = $this;
1030                 // TODO: hard-deprecate in 1.32 (or even 1.31?)
1031                 Hooks::run( 'RevisionInsertComplete', [ &$revision, null, null ] );
1032
1033                 return $rec->getId();
1034         }
1035
1036         /**
1037          * Get the base 36 SHA-1 value for a string of text
1038          * @param string $text
1039          * @return string
1040          */
1041         public static function base36Sha1( $text ) {
1042                 return SlotRecord::base36Sha1( $text );
1043         }
1044
1045         /**
1046          * Create a new null-revision for insertion into a page's
1047          * history. This will not re-save the text, but simply refer
1048          * to the text from the previous version.
1049          *
1050          * Such revisions can for instance identify page rename
1051          * operations and other such meta-modifications.
1052          *
1053          * @param IDatabase $dbw
1054          * @param int $pageId ID number of the page to read from
1055          * @param string $summary Revision's summary
1056          * @param bool $minor Whether the revision should be considered as minor
1057          * @param User|null $user User object to use or null for $wgUser
1058          * @return Revision|null Revision or null on error
1059          */
1060         public static function newNullRevision( $dbw, $pageId, $summary, $minor, $user = null ) {
1061                 global $wgUser;
1062                 if ( !$user ) {
1063                         $user = $wgUser;
1064                 }
1065
1066                 $comment = CommentStoreComment::newUnsavedComment( $summary, null );
1067
1068                 $title = Title::newFromID( $pageId );
1069                 $rec = self::getRevisionStore()->newNullRevision( $dbw, $title, $comment, $minor, $user );
1070
1071                 return new Revision( $rec );
1072         }
1073
1074         /**
1075          * Determine if the current user is allowed to view a particular
1076          * field of this revision, if it's marked as deleted.
1077          *
1078          * @param int $field One of self::DELETED_TEXT,
1079          *                              self::DELETED_COMMENT,
1080          *                              self::DELETED_USER
1081          * @param User|null $user User object to check, or null to use $wgUser
1082          * @return bool
1083          */
1084         public function userCan( $field, User $user = null ) {
1085                 return self::userCanBitfield( $this->getVisibility(), $field, $user );
1086         }
1087
1088         /**
1089          * Determine if the current user is allowed to view a particular
1090          * field of this revision, if it's marked as deleted. This is used
1091          * by various classes to avoid duplication.
1092          *
1093          * @param int $bitfield Current field
1094          * @param int $field One of self::DELETED_TEXT = File::DELETED_FILE,
1095          *                               self::DELETED_COMMENT = File::DELETED_COMMENT,
1096          *                               self::DELETED_USER = File::DELETED_USER
1097          * @param User|null $user User object to check, or null to use $wgUser
1098          * @param Title|null $title A Title object to check for per-page restrictions on,
1099          *                          instead of just plain userrights
1100          * @return bool
1101          */
1102         public static function userCanBitfield( $bitfield, $field, User $user = null,
1103                 Title $title = null
1104         ) {
1105                 global $wgUser;
1106
1107                 if ( !$user ) {
1108                         $user = $wgUser;
1109                 }
1110
1111                 return RevisionRecord::userCanBitfield( $bitfield, $field, $user, $title );
1112         }
1113
1114         /**
1115          * Get rev_timestamp from rev_id, without loading the rest of the row
1116          *
1117          * @param Title $title
1118          * @param int $id
1119          * @param int $flags
1120          * @return string|bool False if not found
1121          */
1122         static function getTimestampFromId( $title, $id, $flags = 0 ) {
1123                 return self::getRevisionStore()->getTimestampFromId( $title, $id, $flags );
1124         }
1125
1126         /**
1127          * Get count of revisions per page...not very efficient
1128          *
1129          * @param IDatabase $db
1130          * @param int $id Page id
1131          * @return int
1132          */
1133         static function countByPageId( $db, $id ) {
1134                 return self::getRevisionStore()->countRevisionsByPageId( $db, $id );
1135         }
1136
1137         /**
1138          * Get count of revisions per page...not very efficient
1139          *
1140          * @param IDatabase $db
1141          * @param Title $title
1142          * @return int
1143          */
1144         static function countByTitle( $db, $title ) {
1145                 return self::getRevisionStore()->countRevisionsByTitle( $db, $title );
1146         }
1147
1148         /**
1149          * Check if no edits were made by other users since
1150          * the time a user started editing the page. Limit to
1151          * 50 revisions for the sake of performance.
1152          *
1153          * @since 1.20
1154          * @deprecated since 1.24
1155          *
1156          * @param IDatabase|int $db The Database to perform the check on. May be given as a
1157          *        Database object or a database identifier usable with wfGetDB.
1158          * @param int $pageId The ID of the page in question
1159          * @param int $userId The ID of the user in question
1160          * @param string $since Look at edits since this time
1161          *
1162          * @return bool True if the given user was the only one to edit since the given timestamp
1163          */
1164         public static function userWasLastToEdit( $db, $pageId, $userId, $since ) {
1165                 if ( is_int( $db ) ) {
1166                         $db = wfGetDB( $db );
1167                 }
1168
1169                 return self::getRevisionStore()->userWasLastToEdit( $db, $pageId, $userId, $since );
1170         }
1171
1172         /**
1173          * Load a revision based on a known page ID and current revision ID from the DB
1174          *
1175          * This method allows for the use of caching, though accessing anything that normally
1176          * requires permission checks (aside from the text) will trigger a small DB lookup.
1177          * The title will also be loaded if $pageIdOrTitle is an integer ID.
1178          *
1179          * @param IDatabase $db ignored!
1180          * @param int|Title $pageIdOrTitle Page ID or Title object
1181          * @param int $revId Known current revision of this page. Determined automatically if not given.
1182          * @return Revision|bool Returns false if missing
1183          * @since 1.28
1184          */
1185         public static function newKnownCurrent( IDatabase $db, $pageIdOrTitle, $revId = 0 ) {
1186                 $title = $pageIdOrTitle instanceof Title
1187                         ? $pageIdOrTitle
1188                         : Title::newFromID( $pageIdOrTitle );
1189
1190                 if ( !$title ) {
1191                         return false;
1192                 }
1193
1194                 $record = self::getRevisionStore()->getKnownCurrentRevision( $title, $revId );
1195                 return $record ? new Revision( $record ) : false;
1196         }
1197 }