includes/Revision.php

   1 <?php
   2
   3 /**
   4  * @todo document
   5  */
   6 class Revision {
   7         protected $mId;
   8         protected $mPage;
   9         protected $mUserText;
  10         protected $mOrigUserText;
  11         protected $mUser;
  12         protected $mMinorEdit;
  13         protected $mTimestamp;
  14         protected $mDeleted;
  15         protected $mSize;
  16         protected $mSha1;
  17         protected $mParentId;
  18         protected $mComment;
  19         protected $mText;
  20         protected $mTextRow;
  21         protected $mTitle;
  22         protected $mCurrent;
  23     protected $mContentModelName;
  24     protected $mContentFormat;
  25     protected $mContent;
  26     protected $mContentHandler;
  27
  28         const DELETED_TEXT = 1;
  29         const DELETED_COMMENT = 2;
  30         const DELETED_USER = 4;
  31         const DELETED_RESTRICTED = 8;
  32         // Convenience field
  33         const SUPPRESSED_USER = 12;
  34         // Audience options for Revision::getText()
  35         const FOR_PUBLIC = 1;
  36         const FOR_THIS_USER = 2;
  37         const RAW = 3;
  38
  39         /**
  40          * Load a page revision from a given revision ID number.
  41          * Returns null if no such revision can be found.
  42          *
  43          * @param $id Integer
  44          * @return Revision or null
  45          */
  46         public static function newFromId( $id ) {
  47                 return Revision::newFromConds( array( 'rev_id' => intval( $id ) ) );
  48         }
  49
  50         /**
  51          * Load either the current, or a specified, revision
  52          * that's attached to a given title. If not attached
  53          * to that title, will return null.
  54          *
  55          * @param $title Title
  56          * @param $id Integer (optional)
  57          * @return Revision or null
  58          */
  59         public static function newFromTitle( $title, $id = 0 ) {
  60                 $conds = array(
  61                         'page_namespace' => $title->getNamespace(),
  62                         'page_title'     => $title->getDBkey()
  63                 );
  64                 if ( $id ) {
  65                         // Use the specified ID
  66                         $conds['rev_id'] = $id;
  67                 } elseif ( wfGetLB()->getServerCount() > 1 ) {
  68                         // Get the latest revision ID from the master
  69                         $dbw = wfGetDB( DB_MASTER );
  70                         $latest = $dbw->selectField( 'page', 'page_latest', $conds, __METHOD__ );
  71                         if ( $latest === false ) {
  72                                 return null; // page does not exist
  73                         }
  74                         $conds['rev_id'] = $latest;
  75                 } else {
  76                         // Use a join to get the latest revision
  77                         $conds[] = 'rev_id=page_latest';
  78                 }
  79                 return Revision::newFromConds( $conds );
  80         }
  81
  82         /**
  83          * Load either the current, or a specified, revision
  84          * that's attached to a given page ID.
  85          * Returns null if no such revision can be found.
  86          *
  87          * @param $revId Integer
  88          * @param $pageId Integer (optional)
  89          * @return Revision or null
  90          */
  91         public static function newFromPageId( $pageId, $revId = 0 ) {
  92                 $conds = array( 'page_id' => $pageId );
  93                 if ( $revId ) {
  94                         $conds['rev_id'] = $revId;
  95                 } elseif ( wfGetLB()->getServerCount() > 1 ) {
  96                         // Get the latest revision ID from the master
  97                         $dbw = wfGetDB( DB_MASTER );
  98                         $latest = $dbw->selectField( 'page', 'page_latest', $conds, __METHOD__ );
  99                         if ( $latest === false ) {
 100                                 return null; // page does not exist
 101                         }
 102                         $conds['rev_id'] = $latest;
 103                 } else {
 104                         $conds[] = 'rev_id = page_latest';
 105                 }
 106                 return Revision::newFromConds( $conds );
 107         }
 108
 109         /**
 110          * Make a fake revision object from an archive table row. This is queried
 111          * for permissions or even inserted (as in Special:Undelete)
 112          * @todo FIXME: Should be a subclass for RevisionDelete. [TS]
 113          *
 114          * @param $row
 115          * @param $overrides array
 116          *
 117          * @return Revision
 118          */
 119         public static function newFromArchiveRow( $row, $overrides = array() ) {
 120                 $attribs = $overrides + array(
 121                         'page'       => isset( $row->ar_page_id ) ? $row->ar_page_id : null,
 122                         'id'         => isset( $row->ar_rev_id ) ? $row->ar_rev_id : null,
 123                         'comment'    => $row->ar_comment,
 124                         'user'       => $row->ar_user,
 125                         'user_text'  => $row->ar_user_text,
 126                         'timestamp'  => $row->ar_timestamp,
 127                         'minor_edit' => $row->ar_minor_edit,
 128                         'text_id'    => isset( $row->ar_text_id ) ? $row->ar_text_id : null,
 129                         'deleted'    => $row->ar_deleted,
 130                         'len'        => $row->ar_len,
 131                         'sha1'       => isset( $row->ar_sha1 ) ? $row->ar_sha1 : null,
 132             'content_model' => isset( $row->ar_content_model ) ? $row->ar_content_model : null,
 133             'content_format'  => isset( $row->ar_content_format ) ? $row->ar_content_format : null,
 134                 );
 135                 if ( isset( $row->ar_text ) && !$row->ar_text_id ) {
 136                         // Pre-1.5 ar_text row
 137                         $attribs['text'] = self::getRevisionText( $row, 'ar_' );
 138                         if ( $attribs['text'] === false ) {
 139                                 throw new MWException( 'Unable to load text from archive row (possibly bug 22624)' );
 140                         }
 141                 }
 142                 return new self( $attribs );
 143         }
 144
 145         /**
 146          * @since 1.19
 147          *
 148          * @param $row
 149          * @return Revision
 150          */
 151         public static function newFromRow( $row ) {
 152                 return new self( $row );
 153         }
 154
 155         /**
 156          * Load a page revision from a given revision ID number.
 157          * Returns null if no such revision can be found.
 158          *
 159          * @param $db DatabaseBase
 160          * @param $id Integer
 161          * @return Revision or null
 162          */
 163         public static function loadFromId( $db, $id ) {
 164                 return Revision::loadFromConds( $db, array( 'rev_id' => intval( $id ) ) );
 165         }
 166
 167         /**
 168          * Load either the current, or a specified, revision
 169          * that's attached to a given page. If not attached
 170          * to that page, will return null.
 171          *
 172          * @param $db DatabaseBase
 173          * @param $pageid Integer
 174          * @param $id Integer
 175          * @return Revision or null
 176          */
 177         public static function loadFromPageId( $db, $pageid, $id = 0 ) {
 178                 $conds = array( 'rev_page' => intval( $pageid ), 'page_id'  => intval( $pageid ) );
 179                 if( $id ) {
 180                         $conds['rev_id'] = intval( $id );
 181                 } else {
 182                         $conds[] = 'rev_id=page_latest';
 183                 }
 184                 return Revision::loadFromConds( $db, $conds );
 185         }
 186
 187         /**
 188          * Load either the current, or a specified, revision
 189          * that's attached to a given page. If not attached
 190          * to that page, will return null.
 191          *
 192          * @param $db DatabaseBase
 193          * @param $title Title
 194          * @param $id Integer
 195          * @return Revision or null
 196          */
 197         public static function loadFromTitle( $db, $title, $id = 0 ) {
 198                 if( $id ) {
 199                         $matchId = intval( $id );
 200                 } else {
 201                         $matchId = 'page_latest';
 202                 }
 203                 return Revision::loadFromConds( $db,
 204                         array( "rev_id=$matchId",
 205                                    'page_namespace' => $title->getNamespace(),
 206                                    'page_title'     => $title->getDBkey() )
 207                 );
 208         }
 209
 210         /**
 211          * Load the revision for the given title with the given timestamp.
 212          * WARNING: Timestamps may in some circumstances not be unique,
 213          * so this isn't the best key to use.
 214          *
 215          * @param $db DatabaseBase
 216          * @param $title Title
 217          * @param $timestamp String
 218          * @return Revision or null
 219          */
 220         public static function loadFromTimestamp( $db, $title, $timestamp ) {
 221                 return Revision::loadFromConds( $db,
 222                         array( 'rev_timestamp'  => $db->timestamp( $timestamp ),
 223                                    'page_namespace' => $title->getNamespace(),
 224                                    'page_title'     => $title->getDBkey() )
 225                 );
 226         }
 227
 228         /**
 229          * Given a set of conditions, fetch a revision.
 230          *
 231          * @param $conditions Array
 232          * @return Revision or null
 233          */
 234         public static function newFromConds( $conditions ) {
 235                 $db = wfGetDB( DB_SLAVE );
 236                 $rev = Revision::loadFromConds( $db, $conditions );
 237                 if( is_null( $rev ) && wfGetLB()->getServerCount() > 1 ) {
 238                         $dbw = wfGetDB( DB_MASTER );
 239                         $rev = Revision::loadFromConds( $dbw, $conditions );
 240                 }
 241                 return $rev;
 242         }
 243
 244         /**
 245          * Given a set of conditions, fetch a revision from
 246          * the given database connection.
 247          *
 248          * @param $db DatabaseBase
 249          * @param $conditions Array
 250          * @return Revision or null
 251          */
 252         private static function loadFromConds( $db, $conditions ) {
 253                 $res = Revision::fetchFromConds( $db, $conditions );
 254                 if( $res ) {
 255                         $row = $res->fetchObject();
 256                         if( $row ) {
 257                                 $ret = new Revision( $row );
 258                                 return $ret;
 259                         }
 260                 }
 261                 $ret = null;
 262                 return $ret;
 263         }
 264
 265         /**
 266          * Return a wrapper for a series of database rows to
 267          * fetch all of a given page's revisions in turn.
 268          * Each row can be fed to the constructor to get objects.
 269          *
 270          * @param $title Title
 271          * @return ResultWrapper
 272          */
 273         public static function fetchRevision( $title ) {
 274                 return Revision::fetchFromConds(
 275                         wfGetDB( DB_SLAVE ),
 276                         array( 'rev_id=page_latest',
 277                                    'page_namespace' => $title->getNamespace(),
 278                                    'page_title'     => $title->getDBkey() )
 279                 );
 280         }
 281
 282         /**
 283          * Given a set of conditions, return a ResultWrapper
 284          * which will return matching database rows with the
 285          * fields necessary to build Revision objects.
 286          *
 287          * @param $db DatabaseBase
 288          * @param $conditions Array
 289          * @return ResultWrapper
 290          */
 291         private static function fetchFromConds( $db, $conditions ) {
 292                 $fields = array_merge(
 293                         self::selectFields(),
 294                         self::selectPageFields(),
 295                         self::selectUserFields()
 296                 );
 297                 return $db->select(
 298                         array( 'revision', 'page', 'user' ),
 299                         $fields,
 300                         $conditions,
 301                         __METHOD__,
 302                         array( 'LIMIT' => 1 ),
 303                         array( 'page' => self::pageJoinCond(), 'user' => self::userJoinCond() )
 304                 );
 305         }
 306
 307         /**
 308          * Return the value of a select() JOIN conds array for the user table.
 309          * This will get user table rows for logged-in users.
 310          * @since 1.19
 311          * @return Array
 312          */
 313         public static function userJoinCond() {
 314                 return array( 'LEFT JOIN', array( 'rev_user != 0', 'user_id = rev_user' ) );
 315         }
 316
 317         /**
 318          * Return the value of a select() page conds array for the paeg table.
 319          * This will assure that the revision(s) are not orphaned from live pages.
 320          * @since 1.19
 321          * @return Array
 322          */
 323         public static function pageJoinCond() {
 324                 return array( 'INNER JOIN', array( 'page_id = rev_page' ) );
 325         }
 326
 327         /**
 328          * Return the list of revision fields that should be selected to create
 329          * a new revision.
 330          * @return array
 331          */
 332         public static function selectFields() {
 333                 return array(
 334                         'rev_id',
 335                         'rev_page',
 336                         'rev_text_id',
 337                         'rev_timestamp',
 338                         'rev_comment',
 339                         'rev_user_text',
 340                         'rev_user',
 341                         'rev_minor_edit',
 342                         'rev_deleted',
 343                         'rev_len',
 344                         'rev_parent_id',
 345                         'rev_sha1',
 346                         'rev_content_format',
 347                         'rev_content_model'
 348                 );
 349         }
 350
 351         /**
 352          * Return the list of text fields that should be selected to read the
 353          * revision text
 354          * @return array
 355          */
 356         public static function selectTextFields() {
 357                 return array(
 358                         'old_text',
 359                         'old_flags'
 360                 );
 361         }
 362
 363         /**
 364          * Return the list of page fields that should be selected from page table
 365          * @return array
 366          */
 367         public static function selectPageFields() {
 368                 return array(
 369                         'page_namespace',
 370                         'page_title',
 371                         'page_id',
 372                         'page_latest'
 373                 );
 374         }
 375
 376         /**
 377          * Return the list of user fields that should be selected from user table
 378          * @return array
 379          */
 380         public static function selectUserFields() {
 381                 return array( 'user_name' );
 382         }
 383
 384         /**
 385          * Constructor
 386          *
 387          * @param $row Mixed: either a database row or an array
 388          * @access private
 389          */
 390         function __construct( $row ) {
 391                 if( is_object( $row ) ) {
 392                         $this->mId        = intval( $row->rev_id );
 393                         $this->mPage      = intval( $row->rev_page );
 394                         $this->mTextId    = intval( $row->rev_text_id );
 395                         $this->mComment   =         $row->rev_comment;
 396                         $this->mUser      = intval( $row->rev_user );
 397                         $this->mMinorEdit = intval( $row->rev_minor_edit );
 398                         $this->mTimestamp =         $row->rev_timestamp;
 399                         $this->mDeleted   = intval( $row->rev_deleted );
 400
 401                         if( !isset( $row->rev_parent_id ) ) {
 402                                 $this->mParentId = is_null( $row->rev_parent_id ) ? null : 0;
 403                         } else {
 404                                 $this->mParentId  = intval( $row->rev_parent_id );
 405                         }
 406
 407                         if( !isset( $row->rev_len ) || is_null( $row->rev_len ) ) {
 408                                 $this->mSize = null;
 409                         } else {
 410                                 $this->mSize = intval( $row->rev_len );
 411                         }
 412
 413                         if ( !isset( $row->rev_sha1 ) ) {
 414                                 $this->mSha1 = null;
 415                         } else {
 416                                 $this->mSha1 = $row->rev_sha1;
 417                         }
 418
 419                         if( isset( $row->page_latest ) ) {
 420                                 $this->mCurrent = ( $row->rev_id == $row->page_latest );
 421                                 $this->mTitle = Title::newFromRow( $row );
 422                         } else {
 423                                 $this->mCurrent = false;
 424                                 $this->mTitle = null;
 425                         }
 426
 427             if( !isset( $row->rev_content_model ) || is_null( $row->rev_content_model ) ) {
 428                 $this->mContentModelName = null; # determine on demand if needed
 429             } else {
 430                 $this->mContentModelName = strval( $row->rev_content_model );
 431             }
 432
 433             if( !isset( $row->rev_content_format ) || is_null( $row->rev_content_format ) ) {
 434                 $this->mContentFormat = null; # determine on demand if needed
 435             } else {
 436                 $this->mContentFormat = strval( $row->rev_content_format );
 437             }
 438
 439                         // Lazy extraction...
 440                         $this->mText      = null;
 441                         if( isset( $row->old_text ) ) {
 442                                 $this->mTextRow = $row;
 443                         } else {
 444                                 // 'text' table row entry will be lazy-loaded
 445                                 $this->mTextRow = null;
 446                         }
 447
 448                         // Use user_name for users and rev_user_text for IPs...
 449                         $this->mUserText = null; // lazy load if left null
 450                         if ( $this->mUser == 0 ) {
 451                                 $this->mUserText = $row->rev_user_text; // IP user
 452                         } elseif ( isset( $row->user_name ) ) {
 453                                 $this->mUserText = $row->user_name; // logged-in user
 454                         }
 455                         $this->mOrigUserText = $row->rev_user_text;
 456                 } elseif( is_array( $row ) ) {
 457                         // Build a new revision to be saved...
 458                         global $wgUser; // ugh
 459
 460
 461             # if we have a content object, use it to set the model and type
 462             if ( !empty( $row['content'] ) ) {
 463                 if ( !empty( $row['text_id'] ) ) { #FIXME: when is that set? test with external store setup! check out insertOn()
 464                     throw new MWException( "Text already stored in external store (id {$row['text_id']}), can't serialize content object" );
 465                 }
 466
 467                 $row['content_model'] = $row['content']->getModelName();
 468                 # note: mContentFormat is initializes later accordingly
 469                 # note: content is serialized later in this method!
 470                 # also set text to null?
 471             }
 472
 473                         $this->mId        = isset( $row['id']         ) ? intval( $row['id']         ) : null;
 474                         $this->mPage      = isset( $row['page']       ) ? intval( $row['page']       ) : null;
 475                         $this->mTextId    = isset( $row['text_id']    ) ? intval( $row['text_id']    ) : null;
 476                         $this->mUserText  = isset( $row['user_text']  ) ? strval( $row['user_text']  ) : $wgUser->getName();
 477                         $this->mUser      = isset( $row['user']       ) ? intval( $row['user']       ) : $wgUser->getId();
 478                         $this->mMinorEdit = isset( $row['minor_edit'] ) ? intval( $row['minor_edit'] ) : 0;
 479                         $this->mTimestamp = isset( $row['timestamp']  ) ? strval( $row['timestamp']  ) : wfTimestampNow();
 480                         $this->mDeleted   = isset( $row['deleted']    ) ? intval( $row['deleted']    ) : 0;
 481                         $this->mSize      = isset( $row['len']        ) ? intval( $row['len']        ) : null;
 482                         $this->mParentId  = isset( $row['parent_id']  ) ? intval( $row['parent_id']  ) : null;
 483                         $this->mSha1      = isset( $row['sha1']  )      ? strval( $row['sha1']  )      : null;
 484
 485             $this->mContentModelName = isset( $row['content_model']  )  ? strval( $row['content_model'] ) : null;
 486             $this->mContentFormat    = isset( $row['content_format']  )   ? strval( $row['content_format'] ) : null;
 487
 488                         // Enforce spacing trimming on supplied text
 489                         $this->mComment   = isset( $row['comment']    ) ?  trim( strval( $row['comment'] ) ) : null;
 490                         $this->mText      = isset( $row['text']       ) ? rtrim( strval( $row['text']    ) ) : null;
 491                         $this->mTextRow   = null;
 492
 493                         $this->mTitle     = null; # Load on demand if needed
 494                         $this->mCurrent   = false;
 495                         # If we still have no length, see it we have the text to figure it out
 496                         if ( !$this->mSize ) {
 497                 #XXX: my be inconsistent with the notion of "size" use for the present content model
 498                                 $this->mSize = is_null( $this->mText ) ? null : strlen( $this->mText );
 499                         }
 500                         # Same for sha1
 501                         if ( $this->mSha1 === null ) {
 502                                 $this->mSha1 = is_null( $this->mText ) ? null : self::base36Sha1( $this->mText );
 503                         }
 504
 505             $this->getContentModelName(); # force lazy init
 506             $this->getContentFormat();      # force lazy init
 507
 508             # if we have a content object, serialize it, overriding mText
 509             if ( !empty( $row['content'] ) ) {
 510                 $handler = $this->getContentHandler();
 511                 $this->mText = $handler->serialize( $row['content'], $this->getContentFormat() );
 512             }
 513                 } else {
 514                         throw new MWException( 'Revision constructor passed invalid row format.' );
 515                 }
 516                 $this->mUnpatrolled = null;
 517
 518         #FIXME: add patch for ar_content_format, ar_content_model, rev_content_format, rev_content_model to installer
 519         #FIXME: add support for ar_content_format, ar_content_model, rev_content_format, rev_content_model to API
 520         }
 521
 522         /**
 523          * Get revision ID
 524          *
 525          * @return Integer
 526          */
 527         public function getId() {
 528                 return $this->mId;
 529         }
 530
 531         /**
 532          * Set the revision ID
 533          *
 534          * @since 1.19
 535          * @param $id Integer
 536          */
 537         public function setId( $id ) {
 538                 $this->mId = $id;
 539         }
 540
 541         /**
 542          * Get text row ID
 543          *
 544          * @return Integer
 545          */
 546         public function getTextId() {
 547                 return $this->mTextId;
 548         }
 549
 550         /**
 551          * Get parent revision ID (the original previous page revision)
 552          *
 553          * @return Integer|null
 554          */
 555         public function getParentId() {
 556                 return $this->mParentId;
 557         }
 558
 559         /**
 560          * Returns the length of the text in this revision, or null if unknown.
 561          *
 562          * @return Integer
 563          */
 564         public function getSize() {
 565                 return $this->mSize;
 566         }
 567
 568         /**
 569          * Returns the base36 sha1 of the text in this revision, or null if unknown.
 570          *
 571          * @return String
 572          */
 573         public function getSha1() {
 574                 return $this->mSha1;
 575         }
 576
 577         /**
 578          * Returns the title of the page associated with this entry.
 579          *
 580          * @return Title
 581          */
 582         public function getTitle() {
 583                 if( isset( $this->mTitle ) ) {
 584                         return $this->mTitle;
 585                 }
 586                 $dbr = wfGetDB( DB_SLAVE );
 587                 $row = $dbr->selectRow(
 588                         array( 'page', 'revision' ),
 589                         self::selectPageFields(),
 590                         array( 'page_id=rev_page',
 591                                    'rev_id' => $this->mId ),
 592                         __METHOD__ );
 593                 if ( $row ) {
 594                         $this->mTitle = Title::newFromRow( $row );
 595                 }
 596                 return $this->mTitle;
 597         }
 598
 599         /**
 600          * Set the title of the revision
 601          *
 602          * @param $title Title
 603          */
 604         public function setTitle( $title ) {
 605                 $this->mTitle = $title;
 606         }
 607
 608         /**
 609          * Get the page ID
 610          *
 611          * @return Integer
 612          */
 613         public function getPage() {
 614                 return $this->mPage;
 615         }
 616
 617         /**
 618          * Fetch revision's user id if it's available to the specified audience.
 619          * If the specified audience does not have access to it, zero will be
 620          * returned.
 621          *
 622          * @param $audience Integer: one of:
 623          *      Revision::FOR_PUBLIC       to be displayed to all users
 624          *      Revision::FOR_THIS_USER    to be displayed to $wgUser
 625          *      Revision::RAW              get the ID regardless of permissions
 626          * @param $user User object to check for, only if FOR_THIS_USER is passed
 627          *              to the $audience parameter
 628          * @return Integer
 629          */
 630         public function getUser( $audience = self::FOR_PUBLIC, User $user = null ) {
 631                 if( $audience == self::FOR_PUBLIC && $this->isDeleted( self::DELETED_USER ) ) {
 632                         return 0;
 633                 } elseif( $audience == self::FOR_THIS_USER && !$this->userCan( self::DELETED_USER, $user ) ) {
 634                         return 0;
 635                 } else {
 636                         return $this->mUser;
 637                 }
 638         }
 639
 640         /**
 641          * Fetch revision's user id without regard for the current user's permissions
 642          *
 643          * @return String
 644          */
 645         public function getRawUser() {
 646                 return $this->mUser;
 647         }
 648
 649         /**
 650          * Fetch revision's username if it's available to the specified audience.
 651          * If the specified audience does not have access to the username, an
 652          * empty string will be returned.
 653          *
 654          * @param $audience Integer: one of:
 655          *      Revision::FOR_PUBLIC       to be displayed to all users
 656          *      Revision::FOR_THIS_USER    to be displayed to $wgUser
 657          *      Revision::RAW              get the text regardless of permissions
 658          * @param $user User object to check for, only if FOR_THIS_USER is passed
 659          *              to the $audience parameter
 660          * @return string
 661          */
 662         public function getUserText( $audience = self::FOR_PUBLIC, User $user = null ) {
 663                 if( $audience == self::FOR_PUBLIC && $this->isDeleted( self::DELETED_USER ) ) {
 664                         return '';
 665                 } elseif( $audience == self::FOR_THIS_USER && !$this->userCan( self::DELETED_USER, $user ) ) {
 666                         return '';
 667                 } else {
 668                         return $this->getRawUserText();
 669                 }
 670         }
 671
 672         /**
 673          * Fetch revision's username without regard for view restrictions
 674          *
 675          * @return String
 676          */
 677         public function getRawUserText() {
 678                 if ( $this->mUserText === null ) {
 679                         $this->mUserText = User::whoIs( $this->mUser ); // load on demand
 680                         if ( $this->mUserText === false ) {
 681                                 # This shouldn't happen, but it can if the wiki was recovered
 682                                 # via importing revs and there is no user table entry yet.
 683                                 $this->mUserText = $this->mOrigUserText;
 684                         }
 685                 }
 686                 return $this->mUserText;
 687         }
 688
 689         /**
 690          * Fetch revision comment if it's available to the specified audience.
 691          * If the specified audience does not have access to the comment, an
 692          * empty string will be returned.
 693          *
 694          * @param $audience Integer: one of:
 695          *      Revision::FOR_PUBLIC       to be displayed to all users
 696          *      Revision::FOR_THIS_USER    to be displayed to $wgUser
 697          *      Revision::RAW              get the text regardless of permissions
 698          * @param $user User object to check for, only if FOR_THIS_USER is passed
 699          *              to the $audience parameter
 700          * @return String
 701          */
 702         function getComment( $audience = self::FOR_PUBLIC, User $user = null ) {
 703                 if( $audience == self::FOR_PUBLIC && $this->isDeleted( self::DELETED_COMMENT ) ) {
 704                         return '';
 705                 } elseif( $audience == self::FOR_THIS_USER && !$this->userCan( self::DELETED_COMMENT, $user ) ) {
 706                         return '';
 707                 } else {
 708                         return $this->mComment;
 709                 }
 710         }
 711
 712         /**
 713          * Fetch revision comment without regard for the current user's permissions
 714          *
 715          * @return String
 716          */
 717         public function getRawComment() {
 718                 return $this->mComment;
 719         }
 720
 721         /**
 722          * @return Boolean
 723          */
 724         public function isMinor() {
 725                 return (bool)$this->mMinorEdit;
 726         }
 727
 728         /**
 729          * @return Integer rcid of the unpatrolled row, zero if there isn't one
 730          */
 731         public function isUnpatrolled() {
 732                 if( $this->mUnpatrolled !== null ) {
 733                         return $this->mUnpatrolled;
 734                 }
 735                 $dbr = wfGetDB( DB_SLAVE );
 736                 $this->mUnpatrolled = $dbr->selectField( 'recentchanges',
 737                         'rc_id',
 738                         array( // Add redundant user,timestamp condition so we can use the existing index
 739                                 'rc_user_text'  => $this->getRawUserText(),
 740                                 'rc_timestamp'  => $dbr->timestamp( $this->getTimestamp() ),
 741                                 'rc_this_oldid' => $this->getId(),
 742                                 'rc_patrolled'  => 0
 743                         ),
 744                         __METHOD__
 745                 );
 746                 return (int)$this->mUnpatrolled;
 747         }
 748
 749         /**
 750          * @param $field int one of DELETED_* bitfield constants
 751          *
 752          * @return Boolean
 753          */
 754         public function isDeleted( $field ) {
 755                 return ( $this->mDeleted & $field ) == $field;
 756         }
 757
 758         /**
 759          * Get the deletion bitfield of the revision
 760          *
 761          * @return int
 762          */
 763         public function getVisibility() {
 764                 return (int)$this->mDeleted;
 765         }
 766
 767         /**
 768          * Fetch revision text if it's available to the specified audience.
 769          * If the specified audience does not have the ability to view this
 770          * revision, an empty string will be returned.
 771          *
 772          * @param $audience Integer: one of:
 773          *      Revision::FOR_PUBLIC       to be displayed to all users
 774          *      Revision::FOR_THIS_USER    to be displayed to $wgUser
 775          *      Revision::RAW              get the text regardless of permissions
 776          * @param $user User object to check for, only if FOR_THIS_USER is passed
 777          *              to the $audience parameter
 778          * @return String
 779      * @deprectaed in 1.20, use getContent() instead
 780          */
 781         public function getText( $audience = self::FOR_PUBLIC, User $user = null ) { #FIXME: deprecated, replace usage! #FIXME: used a LOT!
 782         wfDeprecated( __METHOD__, '1.20' );
 783
 784         $content = $this->getContent();
 785         return ContentHandler::getContentText( $content ); # returns the raw content text, if applicable
 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, null will be returned.
 792      *
 793      * @param $audience Integer: one of:
 794      *      Revision::FOR_PUBLIC       to be displayed to all users
 795      *      Revision::FOR_THIS_USER    to be displayed to $wgUser
 796      *      Revision::RAW              get the text regardless of permissions
 797      * @param $user User object to check for, only if FOR_THIS_USER is passed
 798      *              to the $audience parameter
 799      * @return Content
 800      */
 801     public function getContent( $audience = self::FOR_PUBLIC, User $user = null ) {
 802         if( $audience == self::FOR_PUBLIC && $this->isDeleted( self::DELETED_TEXT ) ) {
 803             return null;
 804         } elseif( $audience == self::FOR_THIS_USER && !$this->userCan( self::DELETED_TEXT, $user ) ) {
 805             return null;
 806         } else {
 807             return $this->getContentInternal();
 808         }
 809     }
 810
 811         /**
 812          * Alias for getText(Revision::FOR_THIS_USER)
 813          *
 814          * @deprecated since 1.17
 815          * @return String
 816          */
 817         public function revText() {
 818                 wfDeprecated( __METHOD__, '1.17' );
 819                 return $this->getText( self::FOR_THIS_USER );
 820         }
 821
 822         /**
 823          * Fetch revision text without regard for view restrictions
 824          *
 825          * @return String
 826          */
 827         public function getRawText() { #FIXME: deprecated, replace usage!
 828                 return $this->getText( self::RAW );
 829         }
 830
 831     protected function getContentInternal() {
 832         if( is_null( $this->mContent ) ) {
 833             // Revision is immutable. Load on demand:
 834
 835             $handler = $this->getContentHandler();
 836             $format = $this->getContentFormat();
 837             $title = $this->getTitle();
 838
 839             if( is_null( $this->mText ) ) {
 840                 // Load text on demand:
 841                 $this->mText = $this->loadText();
 842             }
 843
 844             $this->mContent = is_null( $this->mText ) ? null : $handler->unserialize( $this->mText, $format );
 845         }
 846
 847         return $this->mContent;
 848     }
 849
 850     public function getContentModelName() {
 851         if ( !$this->mContentModelName ) {
 852             $title = $this->getTitle();
 853             $this->mContentModelName = ( $title ? $title->getContentModelName() : CONTENT_MODEL_WIKITEXT );
 854         }
 855
 856         return $this->mContentModelName;
 857     }
 858
 859     public function getContentFormat() {
 860         if ( !$this->mContentFormat ) {
 861             $handler = $this->getContentHandler();
 862             $this->mContentFormat = $handler->getDefaultFormat();
 863         }
 864
 865         return $this->mContentFormat;
 866     }
 867
 868     public function getContentHandler() {
 869         if ( !$this->mContentHandler ) {
 870             $title = $this->getTitle();
 871
 872             if ( $title ) $model = $title->getContentModelName();
 873             else $model = CONTENT_MODEL_WIKITEXT;
 874
 875             $this->mContentHandler = ContentHandler::getForModelName( $model );
 876
 877             #XXX: do we need to verify that mContentHandler supports mContentFormat?
 878             #     otherwise, a fixed content format may cause problems on insert.
 879         }
 880
 881         return $this->mContentHandler;
 882     }
 883
 884         /**
 885          * @return String
 886          */
 887         public function getTimestamp() {
 888                 return wfTimestamp( TS_MW, $this->mTimestamp );
 889         }
 890
 891         /**
 892          * @return Boolean
 893          */
 894         public function isCurrent() {
 895                 return $this->mCurrent;
 896         }
 897
 898         /**
 899          * Get previous revision for this title
 900          *
 901          * @return Revision or null
 902          */
 903         public function getPrevious() {
 904                 if( $this->getTitle() ) {
 905                         $prev = $this->getTitle()->getPreviousRevisionID( $this->getId() );
 906                         if( $prev ) {
 907                                 return Revision::newFromTitle( $this->getTitle(), $prev );
 908                         }
 909                 }
 910                 return null;
 911         }
 912
 913         /**
 914          * Get next revision for this title
 915          *
 916          * @return Revision or null
 917          */
 918         public function getNext() {
 919                 if( $this->getTitle() ) {
 920                         $next = $this->getTitle()->getNextRevisionID( $this->getId() );
 921                         if ( $next ) {
 922                                 return Revision::newFromTitle( $this->getTitle(), $next );
 923                         }
 924                 }
 925                 return null;
 926         }
 927
 928         /**
 929          * Get previous revision Id for this page_id
 930          * This is used to populate rev_parent_id on save
 931          *
 932          * @param $db DatabaseBase
 933          * @return Integer
 934          */
 935         private function getPreviousRevisionId( $db ) {
 936                 if( is_null( $this->mPage ) ) {
 937                         return 0;
 938                 }
 939                 # Use page_latest if ID is not given
 940                 if( !$this->mId ) {
 941                         $prevId = $db->selectField( 'page', 'page_latest',
 942                                 array( 'page_id' => $this->mPage ),
 943                                 __METHOD__ );
 944                 } else {
 945                         $prevId = $db->selectField( 'revision', 'rev_id',
 946                                 array( 'rev_page' => $this->mPage, 'rev_id < ' . $this->mId ),
 947                                 __METHOD__,
 948                                 array( 'ORDER BY' => 'rev_id DESC' ) );
 949                 }
 950                 return intval( $prevId );
 951         }
 952
 953         /**
 954           * Get revision text associated with an old or archive row
 955           * $row is usually an object from wfFetchRow(), both the flags and the text
 956           * field must be included
 957           *
 958           * @param $row Object: the text data
 959           * @param $prefix String: table prefix (default 'old_')
 960           * @return String: text the text requested or false on failure
 961           */
 962         public static function getRevisionText( $row, $prefix = 'old_' ) {
 963                 wfProfileIn( __METHOD__ );
 964
 965                 # Get data
 966                 $textField = $prefix . 'text';
 967                 $flagsField = $prefix . 'flags';
 968
 969                 if( isset( $row->$flagsField ) ) {
 970                         $flags = explode( ',', $row->$flagsField );
 971                 } else {
 972                         $flags = array();
 973                 }
 974
 975                 if( isset( $row->$textField ) ) {
 976                         $text = $row->$textField;
 977                 } else {
 978                         wfProfileOut( __METHOD__ );
 979                         return false;
 980                 }
 981
 982                 # Use external methods for external objects, text in table is URL-only then
 983                 if ( in_array( 'external', $flags ) ) {
 984                         $url = $text;
 985                         $parts = explode( '://', $url, 2 );
 986                         if( count( $parts ) == 1 || $parts[1] == '' ) {
 987                                 wfProfileOut( __METHOD__ );
 988                                 return false;
 989                         }
 990                         $text = ExternalStore::fetchFromURL( $url );
 991                 }
 992
 993                 // If the text was fetched without an error, convert it
 994                 if ( $text !== false ) {
 995                         if( in_array( 'gzip', $flags ) ) {
 996                                 # Deal with optional compression of archived pages.
 997                                 # This can be done periodically via maintenance/compressOld.php, and
 998                                 # as pages are saved if $wgCompressRevisions is set.
 999                                 $text = gzinflate( $text );
1000                         }
1001
1002                         if( in_array( 'object', $flags ) ) {
1003                                 # Generic compressed storage
1004                                 $obj = unserialize( $text );
1005                                 if ( !is_object( $obj ) ) {
1006                                         // Invalid object
1007                                         wfProfileOut( __METHOD__ );
1008                                         return false;
1009                                 }
1010                                 $text = $obj->getText();
1011                         }
1012
1013                         global $wgLegacyEncoding;
1014                         if( $text !== false && $wgLegacyEncoding
1015                                 && !in_array( 'utf-8', $flags ) && !in_array( 'utf8', $flags ) )
1016                         {
1017                                 # Old revisions kept around in a legacy encoding?
1018                                 # Upconvert on demand.
1019                                 # ("utf8" checked for compatibility with some broken
1020                                 #  conversion scripts 2008-12-30)
1021                                 global $wgContLang;
1022                                 $text = $wgContLang->iconv( $wgLegacyEncoding, 'UTF-8', $text );
1023                         }
1024                 }
1025                 wfProfileOut( __METHOD__ );
1026                 return $text;
1027         }
1028
1029         /**
1030          * If $wgCompressRevisions is enabled, we will compress data.
1031          * The input string is modified in place.
1032          * Return value is the flags field: contains 'gzip' if the
1033          * data is compressed, and 'utf-8' if we're saving in UTF-8
1034          * mode.
1035          *
1036          * @param $text Mixed: reference to a text
1037          * @return String
1038          */
1039         public static function compressRevisionText( &$text ) {
1040                 global $wgCompressRevisions;
1041                 $flags = array();
1042
1043                 # Revisions not marked this way will be converted
1044                 # on load if $wgLegacyCharset is set in the future.
1045                 $flags[] = 'utf-8';
1046
1047                 if( $wgCompressRevisions ) {
1048                         if( function_exists( 'gzdeflate' ) ) {
1049                                 $text = gzdeflate( $text );
1050                                 $flags[] = 'gzip';
1051                         } else {
1052                                 wfDebug( "Revision::compressRevisionText() -- no zlib support, not compressing\n" );
1053                         }
1054                 }
1055                 return implode( ',', $flags );
1056         }
1057
1058         /**
1059          * Insert a new revision into the database, returning the new revision ID
1060          * number on success and dies horribly on failure.
1061          *
1062          * @param $dbw DatabaseBase: (master connection)
1063          * @return Integer
1064          */
1065         public function insertOn( $dbw ) {
1066                 global $wgDefaultExternalStore;
1067
1068                 wfProfileIn( __METHOD__ );
1069
1070                 $data = $this->mText;
1071                 $flags = Revision::compressRevisionText( $data );
1072
1073                 # Write to external storage if required
1074                 if( $wgDefaultExternalStore ) {
1075                         // Store and get the URL
1076                         $data = ExternalStore::insertToDefault( $data );
1077                         if( !$data ) {
1078                                 throw new MWException( "Unable to store text to external storage" );
1079                         }
1080                         if( $flags ) {
1081                                 $flags .= ',';
1082                         }
1083                         $flags .= 'external';
1084                 }
1085
1086                 # Record the text (or external storage URL) to the text table
1087                 if( !isset( $this->mTextId ) ) {
1088                         $old_id = $dbw->nextSequenceValue( 'text_old_id_seq' );
1089                         $dbw->insert( 'text',
1090                                 array(
1091                                         'old_id'    => $old_id,
1092                                         'old_text'  => $data,
1093                                         'old_flags' => $flags,
1094                                 ), __METHOD__
1095                         );
1096                         $this->mTextId = $dbw->insertId();
1097                 }
1098
1099                 if ( $this->mComment === null ) $this->mComment = "";
1100
1101                 # Record the edit in revisions
1102                 $rev_id = isset( $this->mId )
1103                         ? $this->mId
1104                         : $dbw->nextSequenceValue( 'revision_rev_id_seq' );
1105
1106         $row = array(
1107             'rev_id'         => $rev_id,
1108             'rev_page'       => $this->mPage,
1109             'rev_text_id'    => $this->mTextId,
1110             'rev_comment'    => $this->mComment,
1111             'rev_minor_edit' => $this->mMinorEdit ? 1 : 0,
1112             'rev_user'       => $this->mUser,
1113             'rev_user_text'  => $this->mUserText,
1114             'rev_timestamp'  => $dbw->timestamp( $this->mTimestamp ),
1115             'rev_deleted'    => $this->mDeleted,
1116             'rev_len'        => $this->mSize,
1117             'rev_parent_id'  => is_null( $this->mParentId )
1118                 ? $this->getPreviousRevisionId( $dbw )
1119                 : $this->mParentId,
1120             'rev_sha1'       => is_null( $this->mSha1 )
1121                 ? Revision::base36Sha1( $this->mText )
1122                 : $this->mSha1,
1123             'rev_content_model'       => $this->getContentModelName(),
1124             'rev_content_format'        => $this->getContentFormat(),
1125         );
1126
1127                 $dbw->insert( 'revision', $row, __METHOD__ );
1128
1129                 $this->mId = !is_null( $rev_id ) ? $rev_id : $dbw->insertId();
1130
1131                 wfRunHooks( 'RevisionInsertComplete', array( &$this, $data, $flags ) );
1132
1133                 wfProfileOut( __METHOD__ );
1134                 return $this->mId;
1135         }
1136
1137         /**
1138          * Get the base 36 SHA-1 value for a string of text
1139          * @param $text String
1140          * @return String
1141          */
1142         public static function base36Sha1( $text ) {
1143                 return wfBaseConvert( sha1( $text ), 16, 36, 31 );
1144         }
1145
1146         /**
1147          * Lazy-load the revision's text.
1148          * Currently hardcoded to the 'text' table storage engine.
1149          *
1150          * @return String
1151          */
1152         protected function loadText() {
1153                 wfProfileIn( __METHOD__ );
1154
1155                 // Caching may be beneficial for massive use of external storage
1156                 global $wgRevisionCacheExpiry, $wgMemc;
1157                 $textId = $this->getTextId();
1158                 $key = wfMemcKey( 'revisiontext', 'textid', $textId );
1159                 if( $wgRevisionCacheExpiry ) {
1160                         $text = $wgMemc->get( $key );
1161                         if( is_string( $text ) ) {
1162                                 wfDebug( __METHOD__ . ": got id $textId from cache\n" );
1163                                 wfProfileOut( __METHOD__ );
1164                                 return $text;
1165                         }
1166                 }
1167
1168                 // If we kept data for lazy extraction, use it now...
1169                 if ( isset( $this->mTextRow ) ) {
1170                         $row = $this->mTextRow;
1171                         $this->mTextRow = null;
1172                 } else {
1173                         $row = null;
1174                 }
1175
1176                 if( !$row ) {
1177                         // Text data is immutable; check slaves first.
1178                         $dbr = wfGetDB( DB_SLAVE );
1179                         $row = $dbr->selectRow( 'text',
1180                                 array( 'old_text', 'old_flags' ),
1181                                 array( 'old_id' => $this->getTextId() ),
1182                                 __METHOD__ );
1183                 }
1184
1185                 if( !$row && wfGetLB()->getServerCount() > 1 ) {
1186                         // Possible slave lag!
1187                         $dbw = wfGetDB( DB_MASTER );
1188                         $row = $dbw->selectRow( 'text',
1189                                 array( 'old_text', 'old_flags' ),
1190                                 array( 'old_id' => $this->getTextId() ),
1191                                 __METHOD__ );
1192                 }
1193
1194                 $text = self::getRevisionText( $row );
1195
1196                 # No negative caching -- negative hits on text rows may be due to corrupted slave servers
1197                 if( $wgRevisionCacheExpiry && $text !== false ) {
1198                         $wgMemc->set( $key, $text, $wgRevisionCacheExpiry );
1199                 }
1200
1201                 wfProfileOut( __METHOD__ );
1202
1203                 return $text;
1204         }
1205
1206         /**
1207          * Create a new null-revision for insertion into a page's
1208          * history. This will not re-save the text, but simply refer
1209          * to the text from the previous version.
1210          *
1211          * Such revisions can for instance identify page rename
1212          * operations and other such meta-modifications.
1213          *
1214          * @param $dbw DatabaseBase
1215          * @param $pageId Integer: ID number of the page to read from
1216          * @param $summary String: revision's summary
1217          * @param $minor Boolean: whether the revision should be considered as minor
1218          * @return Revision|null on error
1219          */
1220         public static function newNullRevision( $dbw, $pageId, $summary, $minor ) {
1221                 wfProfileIn( __METHOD__ );
1222
1223                 $current = $dbw->selectRow(
1224                         array( 'page', 'revision' ),
1225                         array( 'page_latest', 'rev_text_id', 'rev_len', 'rev_sha1',
1226                     'rev_content_model', 'rev_content_format' ),
1227                         array(
1228                                 'page_id' => $pageId,
1229                                 'page_latest=rev_id',
1230                                 ),
1231                         __METHOD__ );
1232
1233                 if( $current ) {
1234                         $revision = new Revision( array(
1235                                 'page'       => $pageId,
1236                                 'comment'    => $summary,
1237                                 'minor_edit' => $minor,
1238                                 'text_id'    => $current->rev_text_id,
1239                                 'parent_id'  => $current->page_latest,
1240                                 'len'        => $current->rev_len,
1241                                 'sha1'       => $current->rev_sha1,
1242                                 'content_model'  => $current->rev_content_model,
1243                                 'content_format'   => $current->rev_content_format
1244                                 ) );
1245                 } else {
1246                         $revision = null;
1247                 }
1248
1249                 wfProfileOut( __METHOD__ );
1250                 return $revision;
1251         }
1252
1253         /**
1254          * Determine if the current user is allowed to view a particular
1255          * field of this revision, if it's marked as deleted.
1256          *
1257          * @param $field Integer:one of self::DELETED_TEXT,
1258          *                              self::DELETED_COMMENT,
1259          *                              self::DELETED_USER
1260          * @param $user User object to check, or null to use $wgUser
1261          * @return Boolean
1262          */
1263         public function userCan( $field, User $user = null ) {
1264                 return self::userCanBitfield( $this->mDeleted, $field, $user );
1265         }
1266
1267         /**
1268          * Determine if the current user is allowed to view a particular
1269          * field of this revision, if it's marked as deleted. This is used
1270          * by various classes to avoid duplication.
1271          *
1272          * @param $bitfield Integer: current field
1273          * @param $field Integer: one of self::DELETED_TEXT = File::DELETED_FILE,
1274          *                               self::DELETED_COMMENT = File::DELETED_COMMENT,
1275          *                               self::DELETED_USER = File::DELETED_USER
1276          * @param $user User object to check, or null to use $wgUser
1277          * @return Boolean
1278          */
1279         public static function userCanBitfield( $bitfield, $field, User $user = null ) {
1280                 if( $bitfield & $field ) { // aspect is deleted
1281                         if ( $bitfield & self::DELETED_RESTRICTED ) {
1282                                 $permission = 'suppressrevision';
1283                         } elseif ( $field & self::DELETED_TEXT ) {
1284                                 $permission = 'deletedtext';
1285                         } else {
1286                                 $permission = 'deletedhistory';
1287                         }
1288                         wfDebug( "Checking for $permission due to $field match on $bitfield\n" );
1289                         if ( $user === null ) {
1290                                 global $wgUser;
1291                                 $user = $wgUser;
1292                         }
1293                         return $user->isAllowed( $permission );
1294                 } else {
1295                         return true;
1296                 }
1297         }
1298
1299         /**
1300          * Get rev_timestamp from rev_id, without loading the rest of the row
1301          *
1302          * @param $title Title
1303          * @param $id Integer
1304          * @return String
1305          */
1306         static function getTimestampFromId( $title, $id ) {
1307                 $dbr = wfGetDB( DB_SLAVE );
1308                 // Casting fix for DB2
1309                 if ( $id == '' ) {
1310                         $id = 0;
1311                 }
1312                 $conds = array( 'rev_id' => $id );
1313                 $conds['rev_page'] = $title->getArticleID();
1314                 $timestamp = $dbr->selectField( 'revision', 'rev_timestamp', $conds, __METHOD__ );
1315                 if ( $timestamp === false && wfGetLB()->getServerCount() > 1 ) {
1316                         # Not in slave, try master
1317                         $dbw = wfGetDB( DB_MASTER );
1318                         $timestamp = $dbw->selectField( 'revision', 'rev_timestamp', $conds, __METHOD__ );
1319                 }
1320                 return wfTimestamp( TS_MW, $timestamp );
1321         }
1322
1323         /**
1324          * Get count of revisions per page...not very efficient
1325          *
1326          * @param $db DatabaseBase
1327          * @param $id Integer: page id
1328          * @return Integer
1329          */
1330         static function countByPageId( $db, $id ) {
1331                 $row = $db->selectRow( 'revision', 'COUNT(*) AS revCount',
1332                         array( 'rev_page' => $id ), __METHOD__ );
1333                 if( $row ) {
1334                         return $row->revCount;
1335                 }
1336                 return 0;
1337         }
1338
1339         /**
1340          * Get count of revisions per page...not very efficient
1341          *
1342          * @param $db DatabaseBase
1343          * @param $title Title
1344          * @return Integer
1345          */
1346         static function countByTitle( $db, $title ) {
1347                 $id = $title->getArticleID();
1348                 if( $id ) {
1349                         return Revision::countByPageId( $db, $id );
1350                 }
1351                 return 0;
1352         }
1353 }