includes/Revision.php

   1 <?php
   2 /**
   3  * @todo document
   4  * @file
   5  */
   6
   7 /**
   8  * @todo document
   9  */
  10 class Revision {
  11         const DELETED_TEXT = 1;
  12         const DELETED_COMMENT = 2;
  13         const DELETED_USER = 4;
  14         const DELETED_RESTRICTED = 8;
  15
  16         // Audience options for Revision::getText()
  17         const FOR_PUBLIC = 1;
  18         const FOR_THIS_USER = 2;
  19         const RAW = 3;
  20
  21         /**
  22          * Load a page revision from a given revision ID number.
  23          * Returns null if no such revision can be found.
  24          *
  25          * @param int $id
  26          * @access public
  27          * @static
  28          */
  29         public static function newFromId( $id ) {
  30                 return Revision::newFromConds(
  31                         array( 'page_id=rev_page',
  32                                'rev_id' => intval( $id ) ) );
  33         }
  34
  35         /**
  36          * Load either the current, or a specified, revision
  37          * that's attached to a given title. If not attached
  38          * to that title, will return null.
  39          *
  40          * @param Title $title
  41          * @param int $id
  42          * @return Revision
  43          */
  44         public static function newFromTitle( $title, $id = 0 ) {
  45                 $conds = array(
  46                         'page_namespace' => $title->getNamespace(),
  47                         'page_title' => $title->getDBkey()
  48                 );
  49                 if ( $id ) {
  50                         // Use the specified ID
  51                         $conds['rev_id'] = $id;
  52                 } elseif ( wfGetLB()->getServerCount() > 1 ) {
  53                         // Get the latest revision ID from the master
  54                         $dbw = wfGetDB( DB_MASTER );
  55                         $latest = $dbw->selectField( 'page', 'page_latest', $conds, __METHOD__ );
  56                         $conds['rev_id'] = $latest;
  57                 } else {
  58                         // Use a join to get the latest revision
  59                         $conds[] = 'rev_id=page_latest';
  60                 }
  61                 $conds[] = 'page_id=rev_page';
  62                 return Revision::newFromConds( $conds );
  63         }
  64
  65         /**
  66          * Load a page revision from a given revision ID number.
  67          * Returns null if no such revision can be found.
  68          *
  69          * @param Database $db
  70          * @param int $id
  71          * @access public
  72          * @static
  73          */
  74         public static function loadFromId( $db, $id ) {
  75                 return Revision::loadFromConds( $db,
  76                         array( 'page_id=rev_page',
  77                                'rev_id' => intval( $id ) ) );
  78         }
  79
  80         /**
  81          * Load either the current, or a specified, revision
  82          * that's attached to a given page. If not attached
  83          * to that page, will return null.
  84          *
  85          * @param Database $db
  86          * @param int $pageid
  87          * @param int $id
  88          * @return Revision
  89          * @access public
  90          * @static
  91          */
  92         public static function loadFromPageId( $db, $pageid, $id = 0 ) {
  93                 $conds=array('page_id=rev_page','rev_page'=>intval( $pageid ), 'page_id'=>intval( $pageid ));
  94                 if( $id ) {
  95                         $conds['rev_id']=intval($id);
  96                 } else {
  97                         $conds[]='rev_id=page_latest';
  98                 }
  99                 return Revision::loadFromConds( $db, $conds );
 100         }
 101
 102         /**
 103          * Load either the current, or a specified, revision
 104          * that's attached to a given page. If not attached
 105          * to that page, will return null.
 106          *
 107          * @param Database $db
 108          * @param Title $title
 109          * @param int $id
 110          * @return Revision
 111          * @access public
 112          * @static
 113          */
 114         public static function loadFromTitle( $db, $title, $id = 0 ) {
 115                 if( $id ) {
 116                         $matchId = intval( $id );
 117                 } else {
 118                         $matchId = 'page_latest';
 119                 }
 120                 return Revision::loadFromConds(
 121                         $db,
 122                         array( "rev_id=$matchId",
 123                                'page_id=rev_page',
 124                                'page_namespace' => $title->getNamespace(),
 125                                'page_title'     => $title->getDBkey() ) );
 126         }
 127
 128         /**
 129          * Load the revision for the given title with the given timestamp.
 130          * WARNING: Timestamps may in some circumstances not be unique,
 131          * so this isn't the best key to use.
 132          *
 133          * @param Database $db
 134          * @param Title $title
 135          * @param string $timestamp
 136          * @return Revision
 137          * @access public
 138          * @static
 139          */
 140         public static function loadFromTimestamp( $db, $title, $timestamp ) {
 141                 return Revision::loadFromConds(
 142                         $db,
 143                         array( 'rev_timestamp'  => $db->timestamp( $timestamp ),
 144                                'page_id=rev_page',
 145                                'page_namespace' => $title->getNamespace(),
 146                                'page_title'     => $title->getDBkey() ) );
 147         }
 148
 149         /**
 150          * Given a set of conditions, fetch a revision.
 151          *
 152          * @param array $conditions
 153          * @return Revision
 154          * @access private
 155          * @static
 156          */
 157         private static function newFromConds( $conditions ) {
 158                 $db = wfGetDB( DB_SLAVE );
 159                 $row = Revision::loadFromConds( $db, $conditions );
 160                 if( is_null( $row ) && wfGetLB()->getServerCount() > 1 ) {
 161                         $dbw = wfGetDB( DB_MASTER );
 162                         $row = Revision::loadFromConds( $dbw, $conditions );
 163                 }
 164                 return $row;
 165         }
 166
 167         /**
 168          * Given a set of conditions, fetch a revision from
 169          * the given database connection.
 170          *
 171          * @param Database $db
 172          * @param array $conditions
 173          * @return Revision
 174          * @access private
 175          * @static
 176          */
 177         private static function loadFromConds( $db, $conditions ) {
 178                 $res = Revision::fetchFromConds( $db, $conditions );
 179                 if( $res ) {
 180                         $row = $res->fetchObject();
 181                         $res->free();
 182                         if( $row ) {
 183                                 $ret = new Revision( $row );
 184                                 return $ret;
 185                         }
 186                 }
 187                 $ret = null;
 188                 return $ret;
 189         }
 190
 191         /**
 192          * Return a wrapper for a series of database rows to
 193          * fetch all of a given page's revisions in turn.
 194          * Each row can be fed to the constructor to get objects.
 195          *
 196          * @param Title $title
 197          * @return ResultWrapper
 198          * @access public
 199          * @static
 200          */
 201         public static function fetchAllRevisions( $title ) {
 202                 return Revision::fetchFromConds(
 203                         wfGetDB( DB_SLAVE ),
 204                         array( 'page_namespace' => $title->getNamespace(),
 205                                'page_title'     => $title->getDBkey(),
 206                                'page_id=rev_page' ) );
 207         }
 208
 209         /**
 210          * Return a wrapper for a series of database rows to
 211          * fetch all of a given page's revisions in turn.
 212          * Each row can be fed to the constructor to get objects.
 213          *
 214          * @param Title $title
 215          * @return ResultWrapper
 216          * @access public
 217          * @static
 218          */
 219         public static function fetchRevision( $title ) {
 220                 return Revision::fetchFromConds(
 221                         wfGetDB( DB_SLAVE ),
 222                         array( 'rev_id=page_latest',
 223                                'page_namespace' => $title->getNamespace(),
 224                                'page_title'     => $title->getDBkey(),
 225                                'page_id=rev_page' ) );
 226         }
 227
 228         /**
 229          * Given a set of conditions, return a ResultWrapper
 230          * which will return matching database rows with the
 231          * fields necessary to build Revision objects.
 232          *
 233          * @param Database $db
 234          * @param array $conditions
 235          * @return ResultWrapper
 236          * @access private
 237          * @static
 238          */
 239         private static function fetchFromConds( $db, $conditions ) {
 240                 $fields = self::selectFields();
 241                 $fields[] = 'page_namespace';
 242                 $fields[] = 'page_title';
 243                 $fields[] = 'page_latest';
 244                 $res = $db->select(
 245                         array( 'page', 'revision' ),
 246                         $fields,
 247                         $conditions,
 248                         __METHOD__,
 249                         array( 'LIMIT' => 1 ) );
 250                 $ret = $db->resultObject( $res );
 251                 return $ret;
 252         }
 253
 254         /**
 255          * Return the list of revision fields that should be selected to create
 256          * a new revision.
 257          */
 258         static function selectFields() {
 259                 return array(
 260                         'rev_id',
 261                         'rev_page',
 262                         'rev_text_id',
 263                         'rev_timestamp',
 264                         'rev_comment',
 265                         'rev_user_text,'.
 266                         'rev_user',
 267                         'rev_minor_edit',
 268                         'rev_deleted',
 269                         'rev_len',
 270                         'rev_parent_id'
 271                 );
 272         }
 273
 274         /**
 275          * Return the list of text fields that should be selected to read the
 276          * revision text
 277          */
 278         static function selectTextFields() {
 279                 return array(
 280                         'old_text',
 281                         'old_flags'
 282                 );
 283         }
 284         /**
 285          * Return the list of page fields that should be selected from page table
 286          */
 287         static function selectPageFields() {
 288                 return array(
 289                         'page_namespace',
 290                         'page_title',
 291                         'page_latest'
 292                 );
 293         }
 294
 295         /**
 296          * @param object $row
 297          * @access private
 298          */
 299         function Revision( $row ) {
 300                 if( is_object( $row ) ) {
 301                         $this->mId        = intval( $row->rev_id );
 302                         $this->mPage      = intval( $row->rev_page );
 303                         $this->mTextId    = intval( $row->rev_text_id );
 304                         $this->mComment   =         $row->rev_comment;
 305                         $this->mUserText  =         $row->rev_user_text;
 306                         $this->mUser      = intval( $row->rev_user );
 307                         $this->mMinorEdit = intval( $row->rev_minor_edit );
 308                         $this->mTimestamp =         $row->rev_timestamp;
 309                         $this->mDeleted   = intval( $row->rev_deleted );
 310
 311                         if( !isset( $row->rev_parent_id ) )
 312                                 $this->mParentId = is_null($row->rev_parent_id) ? null : 0;
 313                         else
 314                                 $this->mParentId  = intval( $row->rev_parent_id );
 315
 316                         if( !isset( $row->rev_len ) || is_null( $row->rev_len ) )
 317                                 $this->mSize = null;
 318                         else
 319                                 $this->mSize = intval( $row->rev_len );
 320
 321                         if( isset( $row->page_latest ) ) {
 322                                 $this->mCurrent = ( $row->rev_id == $row->page_latest );
 323                                 $this->mTitle = Title::makeTitle( $row->page_namespace, $row->page_title );
 324                                 $this->mTitle->resetArticleID( $this->mPage );
 325                         } else {
 326                                 $this->mCurrent = false;
 327                                 $this->mTitle = null;
 328                         }
 329
 330                         // Lazy extraction...
 331                         $this->mText      = null;
 332                         if( isset( $row->old_text ) ) {
 333                                 $this->mTextRow = $row;
 334                         } else {
 335                                 // 'text' table row entry will be lazy-loaded
 336                                 $this->mTextRow = null;
 337                         }
 338                 } elseif( is_array( $row ) ) {
 339                         // Build a new revision to be saved...
 340                         global $wgUser;
 341
 342                         $this->mId        = isset( $row['id']         ) ? intval( $row['id']         ) : null;
 343                         $this->mPage      = isset( $row['page']       ) ? intval( $row['page']       ) : null;
 344                         $this->mTextId    = isset( $row['text_id']    ) ? intval( $row['text_id']    ) : null;
 345                         $this->mUserText  = isset( $row['user_text']  ) ? strval( $row['user_text']  ) : $wgUser->getName();
 346                         $this->mUser      = isset( $row['user']       ) ? intval( $row['user']       ) : $wgUser->getId();
 347                         $this->mMinorEdit = isset( $row['minor_edit'] ) ? intval( $row['minor_edit'] ) : 0;
 348                         $this->mTimestamp = isset( $row['timestamp']  ) ? strval( $row['timestamp']  ) : wfTimestamp( TS_MW );
 349                         $this->mDeleted   = isset( $row['deleted']    ) ? intval( $row['deleted']    ) : 0;
 350                         $this->mSize      = isset( $row['len']        ) ? intval( $row['len']        ) : null;
 351                         $this->mParentId  = isset( $row['parent_id']  ) ? intval( $row['parent_id']  ) : null;
 352
 353                         // Enforce spacing trimming on supplied text
 354                         $this->mComment   = isset( $row['comment']    ) ?  trim( strval( $row['comment'] ) ) : null;
 355                         $this->mText      = isset( $row['text']       ) ? rtrim( strval( $row['text']    ) ) : null;
 356                         $this->mTextRow   = null;
 357
 358                         $this->mTitle     = null; # Load on demand if needed
 359                         $this->mCurrent   = false;
 360                         # If we still have no len_size, see it we have the text to figure it out
 361                         if ( !$this->mSize )
 362                                 $this->mSize      = is_null($this->mText) ? null : strlen($this->mText);
 363                 } else {
 364                         throw new MWException( 'Revision constructor passed invalid row format.' );
 365                 }
 366                 $this->mUnpatrolled = NULL;
 367         }
 368
 369         /**#@+
 370          * @access public
 371          */
 372
 373         /**
 374          * Get revision ID
 375          * @return int
 376          */
 377         public function getId() {
 378                 return $this->mId;
 379         }
 380
 381         /**
 382          * Get text row ID
 383          * @return int
 384          */
 385         public function getTextId() {
 386                 return $this->mTextId;
 387         }
 388
 389         /**
 390          * Get parent revision ID (the original previous page revision)
 391          * @return int
 392          */
 393         public function getParentId() {
 394                 return $this->mParentId;
 395         }
 396
 397         /**
 398          * Returns the length of the text in this revision, or null if unknown.
 399          * @return int
 400          */
 401         public function getSize() {
 402                 return $this->mSize;
 403         }
 404
 405         /**
 406          * Returns the title of the page associated with this entry.
 407          * @return Title
 408          */
 409         public function getTitle() {
 410                 if( isset( $this->mTitle ) ) {
 411                         return $this->mTitle;
 412                 }
 413                 $dbr = wfGetDB( DB_SLAVE );
 414                 $row = $dbr->selectRow(
 415                         array( 'page', 'revision' ),
 416                         array( 'page_namespace', 'page_title' ),
 417                         array( 'page_id=rev_page',
 418                                'rev_id' => $this->mId ),
 419                         'Revision::getTitle' );
 420                 if( $row ) {
 421                         $this->mTitle = Title::makeTitle( $row->page_namespace,
 422                                                           $row->page_title );
 423                 }
 424                 return $this->mTitle;
 425         }
 426
 427         /**
 428          * Set the title of the revision
 429          * @param Title $title
 430          */
 431         public function setTitle( $title ) {
 432                 $this->mTitle = $title;
 433         }
 434
 435         /**
 436          * Get the page ID
 437          * @return int
 438          */
 439         public function getPage() {
 440                 return $this->mPage;
 441         }
 442
 443         /**
 444          * Fetch revision's user id if it's available to the specified audience.
 445          * If the specified audience does not have access to it, zero will be
 446          * returned.
 447          *
 448          * @param integer $audience One of:
 449          *      Revision::FOR_PUBLIC       to be displayed to all users
 450          *      Revision::FOR_THIS_USER    to be displayed to $wgUser
 451          *      Revision::RAW              get the ID regardless of permissions
 452          *
 453          *
 454          * @return int
 455          */
 456         public function getUser( $audience = self::FOR_PUBLIC ) {
 457                 if( $audience == self::FOR_PUBLIC && $this->isDeleted( self::DELETED_USER ) ) {
 458                         return 0;
 459                 } elseif( $audience == self::FOR_THIS_USER && !$this->userCan( self::DELETED_USER ) ) {
 460                         return 0;
 461                 } else {
 462                         return $this->mUser;
 463                 }
 464         }
 465
 466         /**
 467          * Fetch revision's user id without regard for the current user's permissions
 468          * @return string
 469          */
 470         public function getRawUser() {
 471                 return $this->mUser;
 472         }
 473
 474         /**
 475          * Fetch revision's username if it's available to the specified audience.
 476          * If the specified audience does not have access to the username, an
 477          * empty string will be returned.
 478          *
 479          * @param integer $audience One of:
 480          *      Revision::FOR_PUBLIC       to be displayed to all users
 481          *      Revision::FOR_THIS_USER    to be displayed to $wgUser
 482          *      Revision::RAW              get the text regardless of permissions
 483          *
 484          * @return string
 485          */
 486         public function getUserText( $audience = self::FOR_PUBLIC ) {
 487                 if( $audience == self::FOR_PUBLIC && $this->isDeleted( self::DELETED_USER ) ) {
 488                         return "";
 489                 } elseif( $audience == self::FOR_THIS_USER && !$this->userCan( self::DELETED_USER ) ) {
 490                         return "";
 491                 } else {
 492                         return $this->mUserText;
 493                 }
 494         }
 495
 496         /**
 497          * Fetch revision's username without regard for view restrictions
 498          * @return string
 499          */
 500         public function getRawUserText() {
 501                 return $this->mUserText;
 502         }
 503
 504         /**
 505          * Fetch revision comment if it's available to the specified audience.
 506          * If the specified audience does not have access to the comment, an
 507          * empty string will be returned.
 508          *
 509          * @param integer $audience One of:
 510          *      Revision::FOR_PUBLIC       to be displayed to all users
 511          *      Revision::FOR_THIS_USER    to be displayed to $wgUser
 512          *      Revision::RAW              get the text regardless of permissions
 513          *
 514          * @return string
 515          */
 516         function getComment( $audience = self::FOR_PUBLIC ) {
 517                 if( $audience == self::FOR_PUBLIC && $this->isDeleted( self::DELETED_COMMENT ) ) {
 518                         return "";
 519                 } elseif( $audience == self::FOR_THIS_USER && !$this->userCan( self::DELETED_COMMENT ) ) {
 520                         return "";
 521                 } else {
 522                         return $this->mComment;
 523                 }
 524         }
 525
 526         /**
 527          * Fetch revision comment without regard for the current user's permissions
 528          * @return string
 529          */
 530         public function getRawComment() {
 531                 return $this->mComment;
 532         }
 533
 534         /**
 535          * @return bool
 536          */
 537         public function isMinor() {
 538                 return (bool)$this->mMinorEdit;
 539         }
 540
 541         /**
 542          * @return int rcid of the unpatrolled row, zero if there isn't one
 543          */
 544         public function isUnpatrolled() {
 545                 if( $this->mUnpatrolled !== NULL ) {
 546                         return $this->mUnpatrolled;
 547                 }
 548                 $dbr = wfGetDB( DB_SLAVE );
 549                 $this->mUnpatrolled = $dbr->selectField( 'recentchanges',
 550                         'rc_id',
 551                         array( // Add redundant user,timestamp condition so we can use the existing index
 552                                 'rc_user_text'  => $this->getRawUserText(),
 553                                 'rc_timestamp'  => $dbr->timestamp( $this->getTimestamp() ),
 554                                 'rc_this_oldid' => $this->getId(),
 555                                 'rc_patrolled'  => 0
 556                         ),
 557                         __METHOD__
 558                 );
 559                 return (int)$this->mUnpatrolled;
 560         }
 561
 562         /**
 563          * int $field one of DELETED_* bitfield constants
 564          * @return bool
 565          */
 566         public function isDeleted( $field ) {
 567                 return ($this->mDeleted & $field) == $field;
 568         }
 569
 570         /**
 571          * Get the deletion bitfield of the revision
 572          */
 573         public function getVisibility() {
 574                 return (int)$this->mDeleted;
 575         }
 576
 577         /**
 578          * Fetch revision text if it's available to the specified audience.
 579          * If the specified audience does not have the ability to view this
 580          * revision, an empty string will be returned.
 581          *
 582          * @param integer $audience One of:
 583          *      Revision::FOR_PUBLIC       to be displayed to all users
 584          *      Revision::FOR_THIS_USER    to be displayed to $wgUser
 585          *      Revision::RAW              get the text regardless of permissions
 586          *
 587          *
 588          * @return string
 589          */
 590         public function getText( $audience = self::FOR_PUBLIC ) {
 591                 if( $audience == self::FOR_PUBLIC && $this->isDeleted( self::DELETED_TEXT ) ) {
 592                         return "";
 593                 } elseif( $audience == self::FOR_THIS_USER && !$this->userCan( self::DELETED_TEXT ) ) {
 594                         return "";
 595                 } else {
 596                         return $this->getRawText();
 597                 }
 598         }
 599
 600         /**
 601          * Alias for getText(Revision::FOR_THIS_USER)
 602          */
 603         public function revText() {
 604                 return $this->getText( self::FOR_THIS_USER );
 605         }
 606
 607         /**
 608          * Fetch revision text without regard for view restrictions
 609          * @return string
 610          */
 611         public function getRawText() {
 612                 if( is_null( $this->mText ) ) {
 613                         // Revision text is immutable. Load on demand:
 614                         $this->mText = $this->loadText();
 615                 }
 616                 return $this->mText;
 617         }
 618
 619         /**
 620          * @return string
 621          */
 622         public function getTimestamp() {
 623                 return wfTimestamp(TS_MW, $this->mTimestamp);
 624         }
 625
 626         /**
 627          * @return bool
 628          */
 629         public function isCurrent() {
 630                 return $this->mCurrent;
 631         }
 632
 633         /**
 634          * Get previous revision for this title
 635          * @return Revision
 636          */
 637         public function getPrevious() {
 638                 if( $this->getTitle() ) {
 639                         $prev = $this->getTitle()->getPreviousRevisionID( $this->getId() );
 640                         if( $prev ) {
 641                                 return Revision::newFromTitle( $this->getTitle(), $prev );
 642                         }
 643                 }
 644                 return null;
 645         }
 646
 647         /**
 648          * @return Revision
 649          */
 650         public function getNext() {
 651                 if( $this->getTitle() ) {
 652                         $next = $this->getTitle()->getNextRevisionID( $this->getId() );
 653                         if ( $next ) {
 654                                 return Revision::newFromTitle( $this->getTitle(), $next );
 655                         }
 656                 }
 657                 return null;
 658         }
 659
 660         /**
 661          * Get previous revision Id for this page_id
 662          * This is used to populate rev_parent_id on save
 663          * @param Database $db
 664          * @return int
 665          */
 666         private function getPreviousRevisionId( $db ) {
 667                 if( is_null($this->mPage) ) {
 668                         return 0;
 669                 }
 670                 # Use page_latest if ID is not given
 671                 if( !$this->mId ) {
 672                         $prevId = $db->selectField( 'page', 'page_latest',
 673                                 array( 'page_id' => $this->mPage ),
 674                                 __METHOD__ );
 675                 } else {
 676                         $prevId = $db->selectField( 'revision', 'rev_id',
 677                                 array( 'rev_page' => $this->mPage, 'rev_id < ' . $this->mId ),
 678                                 __METHOD__,
 679                                 array( 'ORDER BY' => 'rev_id DESC' ) );
 680                 }
 681                 return intval($prevId);
 682         }
 683
 684         /**
 685           * Get revision text associated with an old or archive row
 686           * $row is usually an object from wfFetchRow(), both the flags and the text
 687           * field must be included
 688           *
 689           * @param object $row The text data
 690           * @param string $prefix table prefix (default 'old_')
 691           * @return string $text|false the text requested
 692           */
 693         public static function getRevisionText( $row, $prefix = 'old_' ) {
 694                 wfProfileIn( __METHOD__ );
 695
 696                 # Get data
 697                 $textField = $prefix . 'text';
 698                 $flagsField = $prefix . 'flags';
 699
 700                 if( isset( $row->$flagsField ) ) {
 701                         $flags = explode( ',', $row->$flagsField );
 702                 } else {
 703                         $flags = array();
 704                 }
 705
 706                 if( isset( $row->$textField ) ) {
 707                         $text = $row->$textField;
 708                 } else {
 709                         wfProfileOut( __METHOD__ );
 710                         return false;
 711                 }
 712
 713                 # Use external methods for external objects, text in table is URL-only then
 714                 if ( in_array( 'external', $flags ) ) {
 715                         $url=$text;
 716                         @list(/* $proto */,$path)=explode('://',$url,2);
 717                         if ($path=="") {
 718                                 wfProfileOut( __METHOD__ );
 719                                 return false;
 720                         }
 721                         $text=ExternalStore::fetchFromURL($url);
 722                 }
 723
 724                 // If the text was fetched without an error, convert it
 725                 if ( $text !== false ) {
 726                         if( in_array( 'gzip', $flags ) ) {
 727                                 # Deal with optional compression of archived pages.
 728                                 # This can be done periodically via maintenance/compressOld.php, and
 729                                 # as pages are saved if $wgCompressRevisions is set.
 730                                 $text = gzinflate( $text );
 731                         }
 732
 733                         if( in_array( 'object', $flags ) ) {
 734                                 # Generic compressed storage
 735                                 $obj = unserialize( $text );
 736                                 if ( !is_object( $obj ) ) {
 737                                         // Invalid object
 738                                         wfProfileOut( __METHOD__ );
 739                                         return false;
 740                                 }
 741                                 $text = $obj->getText();
 742                         }
 743
 744                         global $wgLegacyEncoding;
 745                         if( $wgLegacyEncoding && !in_array( 'utf-8', $flags ) && !in_array( 'utf8', $flags ) ) {
 746                                 # Old revisions kept around in a legacy encoding?
 747                                 # Upconvert on demand.
 748                                 # ("utf8" checked for compatibility with some broken
 749                                 #  conversion scripts 2008-12-30)
 750                                 global $wgInputEncoding, $wgContLang;
 751                                 $text = $wgContLang->iconv( $wgLegacyEncoding, $wgInputEncoding, $text );
 752                         }
 753                 }
 754                 wfProfileOut( __METHOD__ );
 755                 return $text;
 756         }
 757
 758         /**
 759          * If $wgCompressRevisions is enabled, we will compress data.
 760          * The input string is modified in place.
 761          * Return value is the flags field: contains 'gzip' if the
 762          * data is compressed, and 'utf-8' if we're saving in UTF-8
 763          * mode.
 764          *
 765          * @param mixed $text reference to a text
 766          * @return string
 767          */
 768         public static function compressRevisionText( &$text ) {
 769                 global $wgCompressRevisions;
 770                 $flags = array();
 771
 772                 # Revisions not marked this way will be converted
 773                 # on load if $wgLegacyCharset is set in the future.
 774                 $flags[] = 'utf-8';
 775
 776                 if( $wgCompressRevisions ) {
 777                         if( function_exists( 'gzdeflate' ) ) {
 778                                 $text = gzdeflate( $text );
 779                                 $flags[] = 'gzip';
 780                         } else {
 781                                 wfDebug( "Revision::compressRevisionText() -- no zlib support, not compressing\n" );
 782                         }
 783                 }
 784                 return implode( ',', $flags );
 785         }
 786
 787         /**
 788          * Insert a new revision into the database, returning the new revision ID
 789          * number on success and dies horribly on failure.
 790          *
 791          * @param Database $dbw
 792          * @return int
 793          */
 794         public function insertOn( $dbw ) {
 795                 global $wgDefaultExternalStore;
 796
 797                 wfProfileIn( __METHOD__ );
 798
 799                 $data = $this->mText;
 800                 $flags = Revision::compressRevisionText( $data );
 801
 802                 # Write to external storage if required
 803                 if( $wgDefaultExternalStore ) {
 804                         // Store and get the URL
 805                         $data = ExternalStore::insertToDefault( $data );
 806                         if( !$data ) {
 807                                 throw new MWException( "Unable to store text to external storage" );
 808                         }
 809                         if( $flags ) {
 810                                 $flags .= ',';
 811                         }
 812                         $flags .= 'external';
 813                 }
 814
 815                 # Record the text (or external storage URL) to the text table
 816                 if( !isset( $this->mTextId ) ) {
 817                         $old_id = $dbw->nextSequenceValue( 'text_old_id_val' );
 818                         $dbw->insert( 'text',
 819                                 array(
 820                                         'old_id'    => $old_id,
 821                                         'old_text'  => $data,
 822                                         'old_flags' => $flags,
 823                                 ), __METHOD__
 824                         );
 825                         $this->mTextId = $dbw->insertId();
 826                 }
 827
 828                 # Record the edit in revisions
 829                 $rev_id = isset( $this->mId )
 830                         ? $this->mId
 831                         : $dbw->nextSequenceValue( 'rev_rev_id_val' );
 832                 $dbw->insert( 'revision',
 833                         array(
 834                                 'rev_id'         => $rev_id,
 835                                 'rev_page'       => $this->mPage,
 836                                 'rev_text_id'    => $this->mTextId,
 837                                 'rev_comment'    => $this->mComment,
 838                                 'rev_minor_edit' => $this->mMinorEdit ? 1 : 0,
 839                                 'rev_user'       => $this->mUser,
 840                                 'rev_user_text'  => $this->mUserText,
 841                                 'rev_timestamp'  => $dbw->timestamp( $this->mTimestamp ),
 842                                 'rev_deleted'    => $this->mDeleted,
 843                                 'rev_len'            => $this->mSize,
 844                                 'rev_parent_id'  => is_null($this->mParentId) ?
 845                                         $this->getPreviousRevisionId( $dbw ) : $this->mParentId
 846                         ), __METHOD__
 847                 );
 848
 849                 $this->mId = !is_null($rev_id) ? $rev_id : $dbw->insertId();
 850
 851                 wfRunHooks( 'RevisionInsertComplete', array( &$this, $data, $flags ) );
 852
 853                 wfProfileOut( __METHOD__ );
 854                 return $this->mId;
 855         }
 856
 857         /**
 858          * Lazy-load the revision's text.
 859          * Currently hardcoded to the 'text' table storage engine.
 860          *
 861          * @return string
 862          */
 863         private function loadText() {
 864                 wfProfileIn( __METHOD__ );
 865
 866                 // Caching may be beneficial for massive use of external storage
 867                 global $wgRevisionCacheExpiry, $wgMemc;
 868                 $key = wfMemcKey( 'revisiontext', 'textid', $this->getTextId() );
 869                 if( $wgRevisionCacheExpiry ) {
 870                         $text = $wgMemc->get( $key );
 871                         if( is_string( $text ) ) {
 872                                 wfProfileOut( __METHOD__ );
 873                                 return $text;
 874                         }
 875                 }
 876
 877                 // If we kept data for lazy extraction, use it now...
 878                 if ( isset( $this->mTextRow ) ) {
 879                         $row = $this->mTextRow;
 880                         $this->mTextRow = null;
 881                 } else {
 882                         $row = null;
 883                 }
 884
 885                 if( !$row ) {
 886                         // Text data is immutable; check slaves first.
 887                         $dbr = wfGetDB( DB_SLAVE );
 888                         $row = $dbr->selectRow( 'text',
 889                                 array( 'old_text', 'old_flags' ),
 890                                 array( 'old_id' => $this->getTextId() ),
 891                                 __METHOD__ );
 892                 }
 893
 894                 if( !$row && wfGetLB()->getServerCount() > 1 ) {
 895                         // Possible slave lag!
 896                         $dbw = wfGetDB( DB_MASTER );
 897                         $row = $dbw->selectRow( 'text',
 898                                 array( 'old_text', 'old_flags' ),
 899                                 array( 'old_id' => $this->getTextId() ),
 900                                 __METHOD__ );
 901                 }
 902
 903                 $text = self::getRevisionText( $row );
 904
 905                 # No negative caching -- negative hits on text rows may be due to corrupted slave servers
 906                 if( $wgRevisionCacheExpiry && $text !== false ) {
 907                         $wgMemc->set( $key, $text, $wgRevisionCacheExpiry );
 908                 }
 909
 910                 wfProfileOut( __METHOD__ );
 911
 912                 return $text;
 913         }
 914
 915         /**
 916          * Create a new null-revision for insertion into a page's
 917          * history. This will not re-save the text, but simply refer
 918          * to the text from the previous version.
 919          *
 920          * Such revisions can for instance identify page rename
 921          * operations and other such meta-modifications.
 922          *
 923          * @param Database $dbw
 924          * @param int      $pageId ID number of the page to read from
 925          * @param string   $summary
 926          * @param bool     $minor
 927          * @return Revision
 928          */
 929         public static function newNullRevision( $dbw, $pageId, $summary, $minor ) {
 930                 wfProfileIn( __METHOD__ );
 931
 932                 $current = $dbw->selectRow(
 933                         array( 'page', 'revision' ),
 934                         array( 'page_latest', 'rev_text_id', 'rev_len' ),
 935                         array(
 936                                 'page_id' => $pageId,
 937                                 'page_latest=rev_id',
 938                                 ),
 939                         __METHOD__ );
 940
 941                 if( $current ) {
 942                         $revision = new Revision( array(
 943                                 'page'       => $pageId,
 944                                 'comment'    => $summary,
 945                                 'minor_edit' => $minor,
 946                                 'text_id'    => $current->rev_text_id,
 947                                 'parent_id'  => $current->page_latest,
 948                                 'len'        => $current->rev_len
 949                                 ) );
 950                 } else {
 951                         $revision = null;
 952                 }
 953
 954                 wfProfileOut( __METHOD__ );
 955                 return $revision;
 956         }
 957
 958         /**
 959          * Determine if the current user is allowed to view a particular
 960          * field of this revision, if it's marked as deleted.
 961          * @param int $field one of self::DELETED_TEXT,
 962          *                          self::DELETED_COMMENT,
 963          *                          self::DELETED_USER
 964          * @return bool
 965          */
 966         public function userCan( $field ) {
 967                 if( ( $this->mDeleted & $field ) == $field ) {
 968                         global $wgUser;
 969                         $permission = ( $this->mDeleted & self::DELETED_RESTRICTED ) == self::DELETED_RESTRICTED
 970                                 ? 'suppressrevision'
 971                                 : 'deleterevision';
 972                         wfDebug( "Checking for $permission due to $field match on $this->mDeleted\n" );
 973                         return $wgUser->isAllowed( $permission );
 974                 } else {
 975                         return true;
 976                 }
 977         }
 978
 979
 980         /**
 981          * Get rev_timestamp from rev_id, without loading the rest of the row
 982          * @param Title $title
 983          * @param integer $id
 984          */
 985         static function getTimestampFromId( $title, $id ) {
 986                 $dbr = wfGetDB( DB_SLAVE );
 987                 // Casting fix for DB2
 988                 if ($id == '') {
 989                         $id = 0;
 990                 }
 991                 $conds = array( 'rev_id' => $id );
 992                 $conds['rev_page'] = $title->getArticleId();
 993                 $timestamp = $dbr->selectField( 'revision', 'rev_timestamp', $conds, __METHOD__ );
 994                 if ( $timestamp === false && wfGetLB()->getServerCount() > 1 ) {
 995                         # Not in slave, try master
 996                         $dbw = wfGetDB( DB_MASTER );
 997                         $timestamp = $dbw->selectField( 'revision', 'rev_timestamp', $conds, __METHOD__ );
 998                 }
 999                 return wfTimestamp( TS_MW, $timestamp );
1000         }
1001
1002         /**
1003          * Get count of revisions per page...not very efficient
1004          * @param Database $db
1005          * @param int $id, page id
1006          */
1007         static function countByPageId( $db, $id ) {
1008                 $row = $db->selectRow( 'revision', 'COUNT(*) AS revCount',
1009                         array( 'rev_page' => $id ), __METHOD__ );
1010                 if( $row ) {
1011                         return $row->revCount;
1012                 }
1013                 return 0;
1014         }
1015
1016         /**
1017          * Get count of revisions per page...not very efficient
1018          * @param Database $db
1019          * @param Title $title
1020          */
1021         static function countByTitle( $db, $title ) {
1022                 $id = $title->getArticleId();
1023                 if( $id ) {
1024                         return Revision::countByPageId( $db, $id );
1025                 }
1026                 return 0;
1027         }
1028 }
1029
1030 /**
1031  * Aliases for backwards compatibility with 1.6
1032  */
1033 define( 'MW_REV_DELETED_TEXT', Revision::DELETED_TEXT );
1034 define( 'MW_REV_DELETED_COMMENT', Revision::DELETED_COMMENT );
1035 define( 'MW_REV_DELETED_USER', Revision::DELETED_USER );
1036 define( 'MW_REV_DELETED_RESTRICTED', Revision::DELETED_RESTRICTED );