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                         # if we have a content object, override mText and mContentModelName
 494                         if ( !empty( $row['content'] ) ) {
 495                                 $handler = $this->getContentHandler();
 496                                 $this->mContent = $row['content'];
 497
 498                                 $this->mContentModelName = $this->mContent->getModelName();
 499                                 $this->mContentHandler = null;
 500
 501                                 $this->mText = $handler->serializeContent( $row['content'], $this->getContentFormat() );
 502                         }
 503
 504                         $this->mTitle     = null; # Load on demand if needed
 505                         $this->mCurrent   = false;
 506                         # If we still have no length, see it we have the text to figure it out
 507                         if ( !$this->mSize ) {
 508                 #XXX: my be inconsistent with the notion of "size" use for the present content model
 509                                 $this->mSize = is_null( $this->mText ) ? null : strlen( $this->mText );
 510                         }
 511                         # Same for sha1
 512                         if ( $this->mSha1 === null ) {
 513                                 $this->mSha1 = is_null( $this->mText ) ? null : self::base36Sha1( $this->mText );
 514                         }
 515
 516             $this->getContentModelName(); # force lazy init
 517             $this->getContentFormat();      # force lazy init
 518                 } else {
 519                         throw new MWException( 'Revision constructor passed invalid row format.' );
 520                 }
 521                 $this->mUnpatrolled = null;
 522
 523         // @TODO: add support for ar_content_format, ar_content_model, rev_content_format, rev_content_model to API
 524         // @TODO: get rid of $mText
 525         }
 526
 527         /**
 528          * Get revision ID
 529          *
 530          * @return Integer
 531          */
 532         public function getId() {
 533                 return $this->mId;
 534         }
 535
 536         /**
 537          * Set the revision ID
 538          *
 539          * @since 1.19
 540          * @param $id Integer
 541          */
 542         public function setId( $id ) {
 543                 $this->mId = $id;
 544         }
 545
 546         /**
 547          * Get text row ID
 548          *
 549          * @return Integer
 550          */
 551         public function getTextId() {
 552                 return $this->mTextId;
 553         }
 554
 555         /**
 556          * Get parent revision ID (the original previous page revision)
 557          *
 558          * @return Integer|null
 559          */
 560         public function getParentId() {
 561                 return $this->mParentId;
 562         }
 563
 564         /**
 565          * Returns the length of the text in this revision, or null if unknown.
 566          *
 567          * @return Integer
 568          */
 569         public function getSize() {
 570                 return $this->mSize;
 571         }
 572
 573         /**
 574          * Returns the base36 sha1 of the text in this revision, or null if unknown.
 575          *
 576          * @return String
 577          */
 578         public function getSha1() {
 579                 return $this->mSha1;
 580         }
 581
 582         /**
 583          * Returns the title of the page associated with this entry.
 584          *
 585          * @return Title
 586          */
 587         public function getTitle() {
 588                 if( isset( $this->mTitle ) ) {
 589                         return $this->mTitle;
 590                 }
 591                 $dbr = wfGetDB( DB_SLAVE );
 592                 $row = $dbr->selectRow(
 593                         array( 'page', 'revision' ),
 594                         self::selectPageFields(),
 595                         array( 'page_id=rev_page',
 596                                    'rev_id' => $this->mId ),
 597                         __METHOD__ );
 598                 if ( $row ) {
 599                         $this->mTitle = Title::newFromRow( $row );
 600                 }
 601                 return $this->mTitle;
 602         }
 603
 604         /**
 605          * Set the title of the revision
 606          *
 607          * @param $title Title
 608          */
 609         public function setTitle( $title ) {
 610                 $this->mTitle = $title;
 611         }
 612
 613         /**
 614          * Get the page ID
 615          *
 616          * @return Integer
 617          */
 618         public function getPage() {
 619                 return $this->mPage;
 620         }
 621
 622         /**
 623          * Fetch revision's user id if it's available to the specified audience.
 624          * If the specified audience does not have access to it, zero will be
 625          * returned.
 626          *
 627          * @param $audience Integer: one of:
 628          *      Revision::FOR_PUBLIC       to be displayed to all users
 629          *      Revision::FOR_THIS_USER    to be displayed to $wgUser
 630          *      Revision::RAW              get the ID regardless of permissions
 631          * @param $user User object to check for, only if FOR_THIS_USER is passed
 632          *              to the $audience parameter
 633          * @return Integer
 634          */
 635         public function getUser( $audience = self::FOR_PUBLIC, User $user = null ) {
 636                 if( $audience == self::FOR_PUBLIC && $this->isDeleted( self::DELETED_USER ) ) {
 637                         return 0;
 638                 } elseif( $audience == self::FOR_THIS_USER && !$this->userCan( self::DELETED_USER, $user ) ) {
 639                         return 0;
 640                 } else {
 641                         return $this->mUser;
 642                 }
 643         }
 644
 645         /**
 646          * Fetch revision's user id without regard for the current user's permissions
 647          *
 648          * @return String
 649          */
 650         public function getRawUser() {
 651                 return $this->mUser;
 652         }
 653
 654         /**
 655          * Fetch revision's username if it's available to the specified audience.
 656          * If the specified audience does not have access to the username, an
 657          * empty string will be returned.
 658          *
 659          * @param $audience Integer: one of:
 660          *      Revision::FOR_PUBLIC       to be displayed to all users
 661          *      Revision::FOR_THIS_USER    to be displayed to $wgUser
 662          *      Revision::RAW              get the text regardless of permissions
 663          * @param $user User object to check for, only if FOR_THIS_USER is passed
 664          *              to the $audience parameter
 665          * @return string
 666          */
 667         public function getUserText( $audience = self::FOR_PUBLIC, User $user = null ) {
 668                 if( $audience == self::FOR_PUBLIC && $this->isDeleted( self::DELETED_USER ) ) {
 669                         return '';
 670                 } elseif( $audience == self::FOR_THIS_USER && !$this->userCan( self::DELETED_USER, $user ) ) {
 671                         return '';
 672                 } else {
 673                         return $this->getRawUserText();
 674                 }
 675         }
 676
 677         /**
 678          * Fetch revision's username without regard for view restrictions
 679          *
 680          * @return String
 681          */
 682         public function getRawUserText() {
 683                 if ( $this->mUserText === null ) {
 684                         $this->mUserText = User::whoIs( $this->mUser ); // load on demand
 685                         if ( $this->mUserText === false ) {
 686                                 # This shouldn't happen, but it can if the wiki was recovered
 687                                 # via importing revs and there is no user table entry yet.
 688                                 $this->mUserText = $this->mOrigUserText;
 689                         }
 690                 }
 691                 return $this->mUserText;
 692         }
 693
 694         /**
 695          * Fetch revision comment if it's available to the specified audience.
 696          * If the specified audience does not have access to the comment, an
 697          * empty string will be returned.
 698          *
 699          * @param $audience Integer: one of:
 700          *      Revision::FOR_PUBLIC       to be displayed to all users
 701          *      Revision::FOR_THIS_USER    to be displayed to $wgUser
 702          *      Revision::RAW              get the text regardless of permissions
 703          * @param $user User object to check for, only if FOR_THIS_USER is passed
 704          *              to the $audience parameter
 705          * @return String
 706          */
 707         function getComment( $audience = self::FOR_PUBLIC, User $user = null ) {
 708                 if( $audience == self::FOR_PUBLIC && $this->isDeleted( self::DELETED_COMMENT ) ) {
 709                         return '';
 710                 } elseif( $audience == self::FOR_THIS_USER && !$this->userCan( self::DELETED_COMMENT, $user ) ) {
 711                         return '';
 712                 } else {
 713                         return $this->mComment;
 714                 }
 715         }
 716
 717         /**
 718          * Fetch revision comment without regard for the current user's permissions
 719          *
 720          * @return String
 721          */
 722         public function getRawComment() {
 723                 return $this->mComment;
 724         }
 725
 726         /**
 727          * @return Boolean
 728          */
 729         public function isMinor() {
 730                 return (bool)$this->mMinorEdit;
 731         }
 732
 733         /**
 734          * @return Integer rcid of the unpatrolled row, zero if there isn't one
 735          */
 736         public function isUnpatrolled() {
 737                 if( $this->mUnpatrolled !== null ) {
 738                         return $this->mUnpatrolled;
 739                 }
 740                 $dbr = wfGetDB( DB_SLAVE );
 741                 $this->mUnpatrolled = $dbr->selectField( 'recentchanges',
 742                         'rc_id',
 743                         array( // Add redundant user,timestamp condition so we can use the existing index
 744                                 'rc_user_text'  => $this->getRawUserText(),
 745                                 'rc_timestamp'  => $dbr->timestamp( $this->getTimestamp() ),
 746                                 'rc_this_oldid' => $this->getId(),
 747                                 'rc_patrolled'  => 0
 748                         ),
 749                         __METHOD__
 750                 );
 751                 return (int)$this->mUnpatrolled;
 752         }
 753
 754         /**
 755          * @param $field int one of DELETED_* bitfield constants
 756          *
 757          * @return Boolean
 758          */
 759         public function isDeleted( $field ) {
 760                 return ( $this->mDeleted & $field ) == $field;
 761         }
 762
 763         /**
 764          * Get the deletion bitfield of the revision
 765          *
 766          * @return int
 767          */
 768         public function getVisibility() {
 769                 return (int)$this->mDeleted;
 770         }
 771
 772         /**
 773          * Fetch revision text if it's available to the specified audience.
 774          * If the specified audience does not have the ability to view this
 775          * revision, an empty string will be returned.
 776          *
 777          * @param $audience Integer: one of:
 778          *      Revision::FOR_PUBLIC       to be displayed to all users
 779          *      Revision::FOR_THIS_USER    to be displayed to $wgUser
 780          *      Revision::RAW              get the text regardless of permissions
 781          * @param $user User object to check for, only if FOR_THIS_USER is passed
 782          *              to the $audience parameter
 783          * @return String
 784      * @deprectaed in 1.20, use getContent() instead
 785          */
 786         public function getText( $audience = self::FOR_PUBLIC, User $user = null ) { #FIXME: deprecated, replace usage! #FIXME: used a LOT!
 787         wfDeprecated( __METHOD__, '1.20' );
 788
 789         $content = $this->getContent();
 790         return ContentHandler::getContentText( $content ); # returns the raw content text, if applicable
 791         }
 792
 793     /**
 794      * Fetch revision content if it's available to the specified audience.
 795      * If the specified audience does not have the ability to view this
 796      * revision, null will be returned.
 797      *
 798      * @param $audience Integer: one of:
 799      *      Revision::FOR_PUBLIC       to be displayed to all users
 800      *      Revision::FOR_THIS_USER    to be displayed to $wgUser
 801      *      Revision::RAW              get the text regardless of permissions
 802      * @param $user User object to check for, only if FOR_THIS_USER is passed
 803      *              to the $audience parameter
 804      * @return Content
 805      */
 806     public function getContent( $audience = self::FOR_PUBLIC, User $user = null ) {
 807         if( $audience == self::FOR_PUBLIC && $this->isDeleted( self::DELETED_TEXT ) ) {
 808             return null;
 809         } elseif( $audience == self::FOR_THIS_USER && !$this->userCan( self::DELETED_TEXT, $user ) ) {
 810             return null;
 811         } else {
 812             return $this->getContentInternal();
 813         }
 814     }
 815
 816         /**
 817          * Alias for getText(Revision::FOR_THIS_USER)
 818          *
 819          * @deprecated since 1.17
 820          * @return String
 821          */
 822         public function revText() {
 823                 wfDeprecated( __METHOD__, '1.17' );
 824                 return $this->getText( self::FOR_THIS_USER );
 825         }
 826
 827         /**
 828          * Fetch revision text without regard for view restrictions
 829          *
 830          * @return String
 831          */
 832         public function getRawText() { #FIXME: deprecated, replace usage!
 833                 return $this->getText( self::RAW );
 834         }
 835
 836     protected function getContentInternal() {
 837         if( is_null( $this->mContent ) ) {
 838             // Revision is immutable. Load on demand:
 839
 840             $handler = $this->getContentHandler();
 841             $format = $this->getContentFormat();
 842             $title = $this->getTitle();
 843
 844             if( is_null( $this->mText ) ) {
 845                 // Load text on demand:
 846                 $this->mText = $this->loadText();
 847             }
 848
 849             $this->mContent = is_null( $this->mText ) ? null : $handler->unserializeContent( $this->mText, $format );
 850         }
 851
 852         return $this->mContent;
 853     }
 854
 855     public function getContentModelName() {
 856         if ( !$this->mContentModelName ) {
 857             $title = $this->getTitle();
 858             $this->mContentModelName = ( $title ? $title->getContentModelName() : CONTENT_MODEL_WIKITEXT );
 859         }
 860
 861         return $this->mContentModelName;
 862     }
 863
 864     public function getContentFormat() {
 865         if ( !$this->mContentFormat ) {
 866             $handler = $this->getContentHandler();
 867             $this->mContentFormat = $handler->getDefaultFormat();
 868         }
 869
 870         return $this->mContentFormat;
 871     }
 872
 873         /**
 874          * @return ContentHandlert
 875          */
 876     public function getContentHandler() {
 877         if ( !$this->mContentHandler ) {
 878             $model = $this->getContentModelName();
 879             $this->mContentHandler = ContentHandler::getForModelName( $model );
 880
 881             assert( $this->mContentHandler->isSupportedFormat( $this->getContentFormat() ) );
 882         }
 883
 884         return $this->mContentHandler;
 885     }
 886
 887         /**
 888          * @return String
 889          */
 890         public function getTimestamp() {
 891                 return wfTimestamp( TS_MW, $this->mTimestamp );
 892         }
 893
 894         /**
 895          * @return Boolean
 896          */
 897         public function isCurrent() {
 898                 return $this->mCurrent;
 899         }
 900
 901         /**
 902          * Get previous revision for this title
 903          *
 904          * @return Revision or null
 905          */
 906         public function getPrevious() {
 907                 if( $this->getTitle() ) {
 908                         $prev = $this->getTitle()->getPreviousRevisionID( $this->getId() );
 909                         if( $prev ) {
 910                                 return Revision::newFromTitle( $this->getTitle(), $prev );
 911                         }
 912                 }
 913                 return null;
 914         }
 915
 916         /**
 917          * Get next revision for this title
 918          *
 919          * @return Revision or null
 920          */
 921         public function getNext() {
 922                 if( $this->getTitle() ) {
 923                         $next = $this->getTitle()->getNextRevisionID( $this->getId() );
 924                         if ( $next ) {
 925                                 return Revision::newFromTitle( $this->getTitle(), $next );
 926                         }
 927                 }
 928                 return null;
 929         }
 930
 931         /**
 932          * Get previous revision Id for this page_id
 933          * This is used to populate rev_parent_id on save
 934          *
 935          * @param $db DatabaseBase
 936          * @return Integer
 937          */
 938         private function getPreviousRevisionId( $db ) {
 939                 if( is_null( $this->mPage ) ) {
 940                         return 0;
 941                 }
 942                 # Use page_latest if ID is not given
 943                 if( !$this->mId ) {
 944                         $prevId = $db->selectField( 'page', 'page_latest',
 945                                 array( 'page_id' => $this->mPage ),
 946                                 __METHOD__ );
 947                 } else {
 948                         $prevId = $db->selectField( 'revision', 'rev_id',
 949                                 array( 'rev_page' => $this->mPage, 'rev_id < ' . $this->mId ),
 950                                 __METHOD__,
 951                                 array( 'ORDER BY' => 'rev_id DESC' ) );
 952                 }
 953                 return intval( $prevId );
 954         }
 955
 956         /**
 957           * Get revision text associated with an old or archive row
 958           * $row is usually an object from wfFetchRow(), both the flags and the text
 959           * field must be included
 960           *
 961           * @param $row Object: the text data
 962           * @param $prefix String: table prefix (default 'old_')
 963           * @return String: text the text requested or false on failure
 964           */
 965         public static function getRevisionText( $row, $prefix = 'old_' ) {
 966                 wfProfileIn( __METHOD__ );
 967
 968                 # Get data
 969                 $textField = $prefix . 'text';
 970                 $flagsField = $prefix . 'flags';
 971
 972                 if( isset( $row->$flagsField ) ) {
 973                         $flags = explode( ',', $row->$flagsField );
 974                 } else {
 975                         $flags = array();
 976                 }
 977
 978                 if( isset( $row->$textField ) ) {
 979                         $text = $row->$textField;
 980                 } else {
 981                         wfProfileOut( __METHOD__ );
 982                         return false;
 983                 }
 984
 985                 # Use external methods for external objects, text in table is URL-only then
 986                 if ( in_array( 'external', $flags ) ) {
 987                         $url = $text;
 988                         $parts = explode( '://', $url, 2 );
 989                         if( count( $parts ) == 1 || $parts[1] == '' ) {
 990                                 wfProfileOut( __METHOD__ );
 991                                 return false;
 992                         }
 993                         $text = ExternalStore::fetchFromURL( $url );
 994                 }
 995
 996                 // If the text was fetched without an error, convert it
 997                 if ( $text !== false ) {
 998                         if( in_array( 'gzip', $flags ) ) {
 999                                 # Deal with optional compression of archived pages.
1000                                 # This can be done periodically via maintenance/compressOld.php, and
1001                                 # as pages are saved if $wgCompressRevisions is set.
1002                                 $text = gzinflate( $text );
1003                         }
1004
1005                         if( in_array( 'object', $flags ) ) {
1006                                 # Generic compressed storage
1007                                 $obj = unserialize( $text );
1008                                 if ( !is_object( $obj ) ) {
1009                                         // Invalid object
1010                                         wfProfileOut( __METHOD__ );
1011                                         return false;
1012                                 }
1013                                 $text = $obj->getText();
1014                         }
1015
1016                         global $wgLegacyEncoding;
1017                         if( $text !== false && $wgLegacyEncoding
1018                                 && !in_array( 'utf-8', $flags ) && !in_array( 'utf8', $flags ) )
1019                         {
1020                                 # Old revisions kept around in a legacy encoding?
1021                                 # Upconvert on demand.
1022                                 # ("utf8" checked for compatibility with some broken
1023                                 #  conversion scripts 2008-12-30)
1024                                 global $wgContLang;
1025                                 $text = $wgContLang->iconv( $wgLegacyEncoding, 'UTF-8', $text );
1026                         }
1027                 }
1028                 wfProfileOut( __METHOD__ );
1029                 return $text;
1030         }
1031
1032         /**
1033          * If $wgCompressRevisions is enabled, we will compress data.
1034          * The input string is modified in place.
1035          * Return value is the flags field: contains 'gzip' if the
1036          * data is compressed, and 'utf-8' if we're saving in UTF-8
1037          * mode.
1038          *
1039          * @param $text Mixed: reference to a text
1040          * @return String
1041          */
1042         public static function compressRevisionText( &$text ) {
1043                 global $wgCompressRevisions;
1044                 $flags = array();
1045
1046                 # Revisions not marked this way will be converted
1047                 # on load if $wgLegacyCharset is set in the future.
1048                 $flags[] = 'utf-8';
1049
1050                 if( $wgCompressRevisions ) {
1051                         if( function_exists( 'gzdeflate' ) ) {
1052                                 $text = gzdeflate( $text );
1053                                 $flags[] = 'gzip';
1054                         } else {
1055                                 wfDebug( "Revision::compressRevisionText() -- no zlib support, not compressing\n" );
1056                         }
1057                 }
1058                 return implode( ',', $flags );
1059         }
1060
1061         /**
1062          * Insert a new revision into the database, returning the new revision ID
1063          * number on success and dies horribly on failure.
1064          *
1065          * @param $dbw DatabaseBase: (master connection)
1066          * @return Integer
1067          */
1068         public function insertOn( $dbw ) {
1069                 global $wgDefaultExternalStore;
1070
1071                 wfProfileIn( __METHOD__ );
1072
1073                 $data = $this->mText;
1074                 $flags = Revision::compressRevisionText( $data );
1075
1076                 # Write to external storage if required
1077                 if( $wgDefaultExternalStore ) {
1078                         // Store and get the URL
1079                         $data = ExternalStore::insertToDefault( $data );
1080                         if( !$data ) {
1081                                 throw new MWException( "Unable to store text to external storage" );
1082                         }
1083                         if( $flags ) {
1084                                 $flags .= ',';
1085                         }
1086                         $flags .= 'external';
1087                 }
1088
1089                 # Record the text (or external storage URL) to the text table
1090                 if( !isset( $this->mTextId ) ) {
1091                         $old_id = $dbw->nextSequenceValue( 'text_old_id_seq' );
1092                         $dbw->insert( 'text',
1093                                 array(
1094                                         'old_id'    => $old_id,
1095                                         'old_text'  => $data,
1096                                         'old_flags' => $flags,
1097                                 ), __METHOD__
1098                         );
1099                         $this->mTextId = $dbw->insertId();
1100                 }
1101
1102                 if ( $this->mComment === null ) $this->mComment = "";
1103
1104                 # Record the edit in revisions
1105                 $rev_id = isset( $this->mId )
1106                         ? $this->mId
1107                         : $dbw->nextSequenceValue( 'revision_rev_id_seq' );
1108
1109         $row = array(
1110             'rev_id'         => $rev_id,
1111             'rev_page'       => $this->mPage,
1112             'rev_text_id'    => $this->mTextId,
1113             'rev_comment'    => $this->mComment,
1114             'rev_minor_edit' => $this->mMinorEdit ? 1 : 0,
1115             'rev_user'       => $this->mUser,
1116             'rev_user_text'  => $this->mUserText,
1117             'rev_timestamp'  => $dbw->timestamp( $this->mTimestamp ),
1118             'rev_deleted'    => $this->mDeleted,
1119             'rev_len'        => $this->mSize,
1120             'rev_parent_id'  => is_null( $this->mParentId )
1121                 ? $this->getPreviousRevisionId( $dbw )
1122                 : $this->mParentId,
1123             'rev_sha1'       => is_null( $this->mSha1 )
1124                 ? Revision::base36Sha1( $this->mText )
1125                 : $this->mSha1,
1126             'rev_content_model'       => $this->getContentModelName(),
1127             'rev_content_format'        => $this->getContentFormat(),
1128         );
1129
1130                 $dbw->insert( 'revision', $row, __METHOD__ );
1131
1132                 $this->mId = !is_null( $rev_id ) ? $rev_id : $dbw->insertId();
1133
1134                 wfRunHooks( 'RevisionInsertComplete', array( &$this, $data, $flags ) );
1135
1136                 wfProfileOut( __METHOD__ );
1137                 return $this->mId;
1138         }
1139
1140         /**
1141          * Get the base 36 SHA-1 value for a string of text
1142          * @param $text String
1143          * @return String
1144          */
1145         public static function base36Sha1( $text ) {
1146                 return wfBaseConvert( sha1( $text ), 16, 36, 31 );
1147         }
1148
1149         /**
1150          * Lazy-load the revision's text.
1151          * Currently hardcoded to the 'text' table storage engine.
1152          *
1153          * @return String
1154          */
1155         protected function loadText() {
1156                 wfProfileIn( __METHOD__ );
1157
1158                 // Caching may be beneficial for massive use of external storage
1159                 global $wgRevisionCacheExpiry, $wgMemc;
1160                 $textId = $this->getTextId();
1161                 $key = wfMemcKey( 'revisiontext', 'textid', $textId );
1162                 if( $wgRevisionCacheExpiry ) {
1163                         $text = $wgMemc->get( $key );
1164                         if( is_string( $text ) ) {
1165                                 wfDebug( __METHOD__ . ": got id $textId from cache\n" );
1166                                 wfProfileOut( __METHOD__ );
1167                                 return $text;
1168                         }
1169                 }
1170
1171                 // If we kept data for lazy extraction, use it now...
1172                 if ( isset( $this->mTextRow ) ) {
1173                         $row = $this->mTextRow;
1174                         $this->mTextRow = null;
1175                 } else {
1176                         $row = null;
1177                 }
1178
1179                 if( !$row ) {
1180                         // Text data is immutable; check slaves first.
1181                         $dbr = wfGetDB( DB_SLAVE );
1182                         $row = $dbr->selectRow( 'text',
1183                                 array( 'old_text', 'old_flags' ),
1184                                 array( 'old_id' => $this->getTextId() ),
1185                                 __METHOD__ );
1186                 }
1187
1188                 if( !$row && wfGetLB()->getServerCount() > 1 ) {
1189                         // Possible slave lag!
1190                         $dbw = wfGetDB( DB_MASTER );
1191                         $row = $dbw->selectRow( 'text',
1192                                 array( 'old_text', 'old_flags' ),
1193                                 array( 'old_id' => $this->getTextId() ),
1194                                 __METHOD__ );
1195                 }
1196
1197                 $text = self::getRevisionText( $row );
1198
1199                 # No negative caching -- negative hits on text rows may be due to corrupted slave servers
1200                 if( $wgRevisionCacheExpiry && $text !== false ) {
1201                         $wgMemc->set( $key, $text, $wgRevisionCacheExpiry );
1202                 }
1203
1204                 wfProfileOut( __METHOD__ );
1205
1206                 return $text;
1207         }
1208
1209         /**
1210          * Create a new null-revision for insertion into a page's
1211          * history. This will not re-save the text, but simply refer
1212          * to the text from the previous version.
1213          *
1214          * Such revisions can for instance identify page rename
1215          * operations and other such meta-modifications.
1216          *
1217          * @param $dbw DatabaseBase
1218          * @param $pageId Integer: ID number of the page to read from
1219          * @param $summary String: revision's summary
1220          * @param $minor Boolean: whether the revision should be considered as minor
1221          * @return Revision|null on error
1222          */
1223         public static function newNullRevision( $dbw, $pageId, $summary, $minor ) {
1224                 wfProfileIn( __METHOD__ );
1225
1226                 $current = $dbw->selectRow(
1227                         array( 'page', 'revision' ),
1228                         array( 'page_latest', 'rev_text_id', 'rev_len', 'rev_sha1',
1229                     'rev_content_model', 'rev_content_format' ),
1230                         array(
1231                                 'page_id' => $pageId,
1232                                 'page_latest=rev_id',
1233                                 ),
1234                         __METHOD__ );
1235
1236                 if( $current ) {
1237                         $revision = new Revision( array(
1238                                 'page'       => $pageId,
1239                                 'comment'    => $summary,
1240                                 'minor_edit' => $minor,
1241                                 'text_id'    => $current->rev_text_id,
1242                                 'parent_id'  => $current->page_latest,
1243                                 'len'        => $current->rev_len,
1244                                 'sha1'       => $current->rev_sha1,
1245                                 'content_model'  => $current->rev_content_model,
1246                                 'content_format'   => $current->rev_content_format
1247                                 ) );
1248                 } else {
1249                         $revision = null;
1250                 }
1251
1252                 wfProfileOut( __METHOD__ );
1253                 return $revision;
1254         }
1255
1256         /**
1257          * Determine if the current user is allowed to view a particular
1258          * field of this revision, if it's marked as deleted.
1259          *
1260          * @param $field Integer:one of self::DELETED_TEXT,
1261          *                              self::DELETED_COMMENT,
1262          *                              self::DELETED_USER
1263          * @param $user User object to check, or null to use $wgUser
1264          * @return Boolean
1265          */
1266         public function userCan( $field, User $user = null ) {
1267                 return self::userCanBitfield( $this->mDeleted, $field, $user );
1268         }
1269
1270         /**
1271          * Determine if the current user is allowed to view a particular
1272          * field of this revision, if it's marked as deleted. This is used
1273          * by various classes to avoid duplication.
1274          *
1275          * @param $bitfield Integer: current field
1276          * @param $field Integer: one of self::DELETED_TEXT = File::DELETED_FILE,
1277          *                               self::DELETED_COMMENT = File::DELETED_COMMENT,
1278          *                               self::DELETED_USER = File::DELETED_USER
1279          * @param $user User object to check, or null to use $wgUser
1280          * @return Boolean
1281          */
1282         public static function userCanBitfield( $bitfield, $field, User $user = null ) {
1283                 if( $bitfield & $field ) { // aspect is deleted
1284                         if ( $bitfield & self::DELETED_RESTRICTED ) {
1285                                 $permission = 'suppressrevision';
1286                         } elseif ( $field & self::DELETED_TEXT ) {
1287                                 $permission = 'deletedtext';
1288                         } else {
1289                                 $permission = 'deletedhistory';
1290                         }
1291                         wfDebug( "Checking for $permission due to $field match on $bitfield\n" );
1292                         if ( $user === null ) {
1293                                 global $wgUser;
1294                                 $user = $wgUser;
1295                         }
1296                         return $user->isAllowed( $permission );
1297                 } else {
1298                         return true;
1299                 }
1300         }
1301
1302         /**
1303          * Get rev_timestamp from rev_id, without loading the rest of the row
1304          *
1305          * @param $title Title
1306          * @param $id Integer
1307          * @return String
1308          */
1309         static function getTimestampFromId( $title, $id ) {
1310                 $dbr = wfGetDB( DB_SLAVE );
1311                 // Casting fix for DB2
1312                 if ( $id == '' ) {
1313                         $id = 0;
1314                 }
1315                 $conds = array( 'rev_id' => $id );
1316                 $conds['rev_page'] = $title->getArticleID();
1317                 $timestamp = $dbr->selectField( 'revision', 'rev_timestamp', $conds, __METHOD__ );
1318                 if ( $timestamp === false && wfGetLB()->getServerCount() > 1 ) {
1319                         # Not in slave, try master
1320                         $dbw = wfGetDB( DB_MASTER );
1321                         $timestamp = $dbw->selectField( 'revision', 'rev_timestamp', $conds, __METHOD__ );
1322                 }
1323                 return wfTimestamp( TS_MW, $timestamp );
1324         }
1325
1326         /**
1327          * Get count of revisions per page...not very efficient
1328          *
1329          * @param $db DatabaseBase
1330          * @param $id Integer: page id
1331          * @return Integer
1332          */
1333         static function countByPageId( $db, $id ) {
1334                 $row = $db->selectRow( 'revision', 'COUNT(*) AS revCount',
1335                         array( 'rev_page' => $id ), __METHOD__ );
1336                 if( $row ) {
1337                         return $row->revCount;
1338                 }
1339                 return 0;
1340         }
1341
1342         /**
1343          * Get count of revisions per page...not very efficient
1344          *
1345          * @param $db DatabaseBase
1346          * @param $title Title
1347          * @return Integer
1348          */
1349         static function countByTitle( $db, $title ) {
1350                 $id = $title->getArticleID();
1351                 if( $id ) {
1352                         return Revision::countByPageId( $db, $id );
1353                 }
1354                 return 0;
1355         }
1356 }