includes/Revision.php

   1 <?php
   2 /**
   3  * @package MediaWiki
   4  * @todo document
   5  */
   6
   7 /** */
   8 require_once( 'Database.php' );
   9 require_once( 'Article.php' );
  10
  11 /**
  12  * @package MediaWiki
  13  * @todo document
  14  */
  15 class Revision {
  16         /**
  17          * Load a page revision from a given revision ID number.
  18          * Returns null if no such revision can be found.
  19          *
  20          * @param int $id
  21          * @static
  22          * @access public
  23          */
  24         function &newFromId( $id ) {
  25                 return Revision::newFromConds(
  26                         array( 'page_id=rev_page',
  27                                'rev_id' => IntVal( $id ) ) );
  28         }
  29
  30         /**
  31          * Load either the current, or a specified, revision
  32          * that's attached to a given title. If not attached
  33          * to that title, will return null.
  34          *
  35          * @param Title $title
  36          * @param int $id
  37          * @return Revision
  38          * @access public
  39          * @static
  40          */
  41         function &newFromTitle( &$title, $id = 0 ) {
  42                 if( $id ) {
  43                         $matchId = IntVal( $id );
  44                 } else {
  45                         $matchId = 'page_latest';
  46                 }
  47                 return Revision::newFromConds(
  48                         array( "rev_id=$matchId",
  49                                'page_id=rev_page',
  50                                'page_namespace' => $title->getNamespace(),
  51                                'page_title'     => $title->getDbkey() ) );
  52         }
  53
  54         /**
  55          * Load either the current, or a specified, revision
  56          * that's attached to a given page. If not attached
  57          * to that page, will return null.
  58          *
  59          * @param Database $db
  60          * @param int $pageid
  61          * @param int $id
  62          * @return Revision
  63          * @access public
  64          */
  65         function &loadFromPageId( &$db, $pageid, $id = 0 ) {
  66                 if( $id ) {
  67                         $matchId = IntVal( $id );
  68                 } else {
  69                         $matchId = 'page_latest';
  70                 }
  71                 return Revision::loadFromConds(
  72                         $db,
  73                         array( "rev_id=$matchId",
  74                                'rev_page' => IntVal( $pageid ),
  75                                'page_id=rev_page' ) );
  76         }
  77
  78         /**
  79          * Load the revision for the given title with the given timestamp.
  80          * WARNING: Timestamps may in some circumstances not be unique,
  81          * so this isn't the best key to use.
  82          *
  83          * @param Database $db
  84          * @param Title $title
  85          * @param string $timestamp
  86          * @return Revision
  87          * @access public
  88          * @static
  89          */
  90         function &loadFromTimestamp( &$db, &$title, $timestamp ) {
  91                 return Revision::loadFromConds(
  92                         $db,
  93                         array( 'rev_timestamp'  => $db->timestamp( $timestamp ),
  94                                'page_id=rev_page',
  95                                'page_namespace' => $title->getNamespace(),
  96                                'page_title'     => $title->getDbkey() ) );
  97         }
  98
  99         /**
 100          * Given a set of conditions, fetch a revision.
 101          *
 102          * @param array $conditions
 103          * @return Revision
 104          * @static
 105          * @access private
 106          */
 107         function &newFromConds( $conditions ) {
 108                 $db =& wfGetDB( DB_SLAVE );
 109                 return Revision::loadFromConds( $db, $conditions );
 110         }
 111
 112         /**
 113          * Given a set of conditions, fetch a revision from
 114          * the given database connection.
 115          *
 116          * @param Database $db
 117          * @param array $conditions
 118          * @return Revision
 119          * @static
 120          * @access private
 121          */
 122         function &loadFromConds( &$db, $conditions ) {
 123                 $res =& Revision::fetchFromConds( $db, $conditions );
 124                 if( $res ) {
 125                         $row = $res->fetchObject();
 126                         $res->free();
 127                         if( $row ) {
 128                                 return new Revision( $row );
 129                         }
 130                 }
 131                 return null;
 132         }
 133
 134         /**
 135          * Return a wrapper for a series of database rows to
 136          * fetch all of a given page's revisions in turn.
 137          * Each row can be fed to the constructor to get objects.
 138          *
 139          * @param Title $title
 140          * @return ResultWrapper
 141          * @static
 142          * @access public
 143          */
 144         function &fetchAllRevisions( &$title ) {
 145                 return Revision::fetchFromConds(
 146                         wfGetDB( DB_SLAVE ),
 147                         array( 'page_namespace' => $title->getNamespace(),
 148                                'page_title'     => $title->getDbkey(),
 149                                'page_id=rev_page' ) );
 150         }
 151
 152         /**
 153          * Return a wrapper for a series of database rows to
 154          * fetch all of a given page's revisions in turn.
 155          * Each row can be fed to the constructor to get objects.
 156          *
 157          * @param Title $title
 158          * @return ResultWrapper
 159          * @static
 160          * @access public
 161          */
 162         function &fetchRevision( &$title ) {
 163                 return Revision::fetchFromConds(
 164                         wfGetDB( DB_SLAVE ),
 165                         array( 'rev_id=page_latest',
 166                                'page_namespace' => $title->getNamespace(),
 167                                'page_title'     => $title->getDbkey(),
 168                                'page_id=rev_page' ) );
 169         }
 170
 171         /**
 172          * Given a set of conditions, return a ResultWrapper
 173          * which will return matching database rows with the
 174          * fields necessary to build Revision objects.
 175          *
 176          * @param Database $db
 177          * @param array $conditions
 178          * @return ResultWrapper
 179          * @static
 180          * @access private
 181          */
 182         function &fetchFromConds( &$db, $conditions ) {
 183                 $res = $db->select(
 184                         array( 'page', 'revision' ),
 185                         array( 'page_namespace',
 186                                'page_title',
 187                                'page_latest',
 188                                'rev_id',
 189                                'rev_page',
 190                                'rev_text_id',
 191                                'rev_comment',
 192                                'rev_user_text',
 193                                'rev_user',
 194                                'rev_minor_edit',
 195                                'rev_timestamp',
 196                                'rev_deleted' ),
 197                         $conditions,
 198                         'Revision::fetchRow',
 199                         array( 'LIMIT' => 1 ) );
 200                 return $db->resultObject( $res );
 201         }
 202
 203         /**
 204          * @param object $row
 205          * @access private
 206          */
 207         function Revision( $row ) {
 208                 if( is_object( $row ) ) {
 209                         $this->mId        = IntVal( $row->rev_id );
 210                         $this->mPage      = IntVal( $row->rev_page );
 211                         $this->mTextId    = IntVal( $row->rev_text_id );
 212                         $this->mComment   =         $row->rev_comment;
 213                         $this->mUserText  =         $row->rev_user_text;
 214                         $this->mUser      = IntVal( $row->rev_user );
 215                         $this->mMinorEdit = IntVal( $row->rev_minor_edit );
 216                         $this->mTimestamp =         $row->rev_timestamp;
 217                         $this->mDeleted   = IntVal( $row->rev_deleted );
 218
 219                         $this->mCurrent   = ( $row->rev_id == $row->page_latest );
 220                         $this->mTitle     = Title::makeTitle( $row->page_namespace,
 221                                                               $row->page_title );
 222
 223                         if( isset( $row->old_text ) ) {
 224                                 $this->mText  = $this->getRevisionText( $row );
 225                         } else {
 226                                 $this->mText  = null;
 227                         }
 228                 } elseif( is_array( $row ) ) {
 229                         // Build a new revision to be saved...
 230                         global $wgUser;
 231
 232                         $this->mId        = isset( $row['id']         ) ? IntVal( $row['id']         ) : null;
 233                         $this->mPage      = isset( $row['page']       ) ? IntVal( $row['page']       ) : null;
 234                         $this->mTextId    = isset( $row['text_id']    ) ? IntVal( $row['text_id']    ) : null;
 235                         $this->mUserText  = isset( $row['user_text']  ) ? StrVal( $row['user_text']  ) : $wgUser->getName();
 236                         $this->mUser      = isset( $row['user']       ) ? IntVal( $row['user']       ) : $wgUser->getId();
 237                         $this->mMinorEdit = isset( $row['minor_edit'] ) ? IntVal( $row['minor_edit'] ) : 0;
 238                         $this->mTimestamp = isset( $row['timestamp']  ) ? StrVal( $row['timestamp']  ) : wfTimestamp( TS_MW );
 239                         $this->mDeleted   = isset( $row['deleted']    ) ? IntVal( $row['deleted']    ) : 0;
 240
 241                         // Enforce spacing trimming on supplied text
 242                         $this->mComment   = isset( $row['comment']    ) ?  trim( StrVal( $row['comment'] ) ) : null;
 243                         $this->mText      = isset( $row['text']       ) ? rtrim( StrVal( $row['text']    ) ) : null;
 244
 245                         $this->mTitle     = null; # Load on demand if needed
 246                         $this->mCurrent   = false;
 247                 } else {
 248                         wfDebugDieBacktrace( 'Revision constructor passed invalid row format.' );
 249                 }
 250         }
 251
 252         /**#@+
 253          * @access public
 254          */
 255
 256         /**
 257          * @return int
 258          */
 259         function getId() {
 260                 return $this->mId;
 261         }
 262
 263         /**
 264          * @return int
 265          */
 266         function getTextId() {
 267                 return $this->mTextId;
 268         }
 269
 270         /**
 271          * Returns the title of the page associated with this entry.
 272          * @return Title
 273          */
 274         function &getTitle() {
 275                 if( isset( $this->mTitle ) ) {
 276                         return $this->mTitle;
 277                 }
 278                 $dbr =& wfGetDB( DB_SLAVE );
 279                 $row = $dbr->selectRow(
 280                         array( 'page', 'revision' ),
 281                         array( 'page_namespace', 'page_title' ),
 282                         array( 'page_id=rev_page',
 283                                'rev_id' => $this->mId ),
 284                         'Revision::getTItle' );
 285                 if( $row ) {
 286                         $this->mTitle =& Title::makeTitle( $row->page_namespace,
 287                                                            $row->page_title );
 288                 }
 289                 return $this->mTitle;
 290         }
 291
 292         /**
 293          * @return int
 294          */
 295         function getPage() {
 296                 return $this->mPage;
 297         }
 298
 299         /**
 300          * @return int
 301          */
 302         function getUser() {
 303                 return $this->mUser;
 304         }
 305
 306         /**
 307          * @return string
 308          */
 309         function getUserText() {
 310                 return $this->mUserText;
 311         }
 312
 313         /**
 314          * @return string
 315          */
 316         function getComment() {
 317                 return $this->mComment;
 318         }
 319
 320         /**
 321          * @return bool
 322          */
 323         function isMinor() {
 324                 return (bool)$this->mMinorEdit;
 325         }
 326
 327         /**
 328          * @return bool
 329          */
 330         function isDeleted() {
 331                 return (bool)$this->mDeleted;
 332         }
 333
 334         /**
 335          * @return string
 336          */
 337         function getText() {
 338                 if( is_null( $this->mText ) ) {
 339                         // Revision text is immutable. Load on demand:
 340                         $this->mText = $this->loadText();
 341                 }
 342                 return $this->mText;
 343         }
 344
 345         /**
 346          * @return string
 347          */
 348         function getTimestamp() {
 349                 return $this->mTimestamp;
 350         }
 351
 352         /**
 353          * @return bool
 354          */
 355         function isCurrent() {
 356                 return $this->mCurrent;
 357         }
 358
 359         /**
 360          * @return Revision
 361          */
 362         function &getPrevious() {
 363                 $prev = $this->mTitle->getPreviousRevisionID( $this->mId );
 364                 return Revision::newFromTitle( $this->mTitle, $prev );
 365         }
 366
 367         /**
 368          * @return Revision
 369          */
 370         function &getNext() {
 371                 $next = $this->mTitle->getNextRevisionID( $this->mId );
 372                 return Revision::newFromTitle( $this->mTitle, $next );
 373         }
 374         /**#@-*/
 375
 376         /**
 377           * Get revision text associated with an old or archive row
 378           * $row is usually an object from wfFetchRow(), both the flags and the text
 379           * field must be included
 380           * @static
 381           * @param integer $row Id of a row
 382           * @param string $prefix table prefix (default 'old_')
 383           * @return string $text|false the text requested
 384           */
 385         function getRevisionText( $row, $prefix = 'old_' ) {
 386                 $fname = 'Revision::getRevisionText';
 387                 wfProfileIn( $fname );
 388
 389                 # Get data
 390                 $textField = $prefix . 'text';
 391                 $flagsField = $prefix . 'flags';
 392
 393                 if( isset( $row->$flagsField ) ) {
 394                         $flags = explode( ',', $row->$flagsField );
 395                 } else {
 396                         $flags = array();
 397                 }
 398
 399                 if( isset( $row->$textField ) ) {
 400                         $text = $row->$textField;
 401                 } else {
 402                         wfProfileOut( $fname );
 403                         return false;
 404                 }
 405
 406                 # Use external methods for external objects, text in table is URL-only then
 407                 if ( in_array( 'external', $flags ) ) {
 408                         $url=$text;
 409                         @list($proto,$path)=explode('://',$url,2);
 410                         if ($path=="") {
 411                                 wfProfileOut( $fname );
 412                                 return false;
 413                         }
 414                         require_once('ExternalStore.php');
 415                         $text=ExternalStore::fetchFromURL($url);
 416                 }
 417
 418                 if( in_array( 'gzip', $flags ) ) {
 419                         # Deal with optional compression of archived pages.
 420                         # This can be done periodically via maintenance/compressOld.php, and
 421                         # as pages are saved if $wgCompressRevisions is set.
 422                         $text = gzinflate( $text );
 423                 }
 424
 425                 if( in_array( 'object', $flags ) ) {
 426                         # Generic compressed storage
 427                         $obj = unserialize( $text );
 428
 429                         # Bugger, corrupted my test database by double-serializing
 430                         if ( !is_object( $obj ) ) {
 431                                 $obj = unserialize( $obj );
 432                         }
 433
 434                         $text = $obj->getText();
 435                 }
 436
 437                 global $wgLegacyEncoding;
 438                 if( $wgLegacyEncoding && !in_array( 'utf-8', $flags ) ) {
 439                         # Old revisions kept around in a legacy encoding?
 440                         # Upconvert on demand.
 441                         global $wgInputEncoding, $wgContLang;
 442                         $text = $wgContLang->iconv( $wgLegacyEncoding, $wgInputEncoding, $text );
 443                 }
 444                 wfProfileOut( $fname );
 445                 return $text;
 446         }
 447
 448         /**
 449          * If $wgCompressRevisions is enabled, we will compress data.
 450          * The input string is modified in place.
 451          * Return value is the flags field: contains 'gzip' if the
 452          * data is compressed, and 'utf-8' if we're saving in UTF-8
 453          * mode.
 454          *
 455          * @static
 456          * @param mixed $text reference to a text
 457          * @return string
 458          */
 459         function compressRevisionText( &$text ) {
 460                 global $wgCompressRevisions;
 461                 $flags = array();
 462
 463                 # Revisions not marked this way will be converted
 464                 # on load if $wgLegacyCharset is set in the future.
 465                 $flags[] = 'utf-8';
 466
 467                 if( $wgCompressRevisions ) {
 468                         if( function_exists( 'gzdeflate' ) ) {
 469                                 $text = gzdeflate( $text );
 470                                 $flags[] = 'gzip';
 471                         } else {
 472                                 wfDebug( "Revision::compressRevisionText() -- no zlib support, not compressing\n" );
 473                         }
 474                 }
 475                 return implode( ',', $flags );
 476         }
 477
 478         /**
 479          * Insert a new revision into the database, returning the new revision ID
 480          * number on success and dies horribly on failure.
 481          *
 482          * @param Database $dbw
 483          * @return int
 484          */
 485         function insertOn( &$dbw ) {
 486                 $fname = 'Revision::insertOn';
 487                 wfProfileIn( $fname );
 488
 489                 $mungedText = $this->mText;
 490                 $flags = Revision::compressRevisionText( $mungedText );
 491
 492                 # Record the text to the text table
 493                 if( !isset( $this->mTextId ) ) {
 494                         $old_id = $dbw->nextSequenceValue( 'text_old_id_val' );
 495                         $dbw->insert( 'text',
 496                                 array(
 497                                         'old_id'    => $old_id,
 498                                         'old_text'  => $mungedText,
 499                                         'old_flags' => $flags,
 500                                 ), $fname
 501                         );
 502                         $this->mTextId = $dbw->insertId();
 503                 }
 504
 505                 # Record the edit in revisions
 506                 $rev_id = isset( $this->mId )
 507                         ? $this->mId
 508                         : $dbw->nextSequenceValue( 'rev_rev_id_val' );
 509                 $dbw->insert( 'revision',
 510                         array(
 511                                 'rev_id'         => $rev_id,
 512                                 'rev_page'       => $this->mPage,
 513                                 'rev_text_id'    => $this->mTextId,
 514                                 'rev_comment'    => $this->mComment,
 515                                 'rev_minor_edit' => $this->mMinorEdit ? 1 : 0,
 516                                 'rev_user'       => $this->mUser,
 517                                 'rev_user_text'  => $this->mUserText,
 518                                 'rev_timestamp'  => $dbw->timestamp( $this->mTimestamp ),
 519                                 'rev_deleted'    => $this->mDeleted,
 520                         ), $fname
 521                 );
 522
 523                 $this->mId = $dbw->insertId();
 524
 525                 wfProfileOut( $fname );
 526                 return $this->mId;
 527         }
 528
 529         /**
 530          * Lazy-load the revision's text.
 531          * Currently hardcoded to the 'text' table storage engine.
 532          *
 533          * @return string
 534          * @access private
 535          */
 536         function loadText() {
 537                 $fname = 'Revision::loadText';
 538                 wfProfileIn( $fname );
 539
 540                 $dbr =& wfGetDB( DB_SLAVE );
 541                 $row = $dbr->selectRow( 'text',
 542                         array( 'old_text', 'old_flags' ),
 543                         array( 'old_id' => $this->getTextId() ),
 544                         $fname);
 545
 546                 $text = Revision::getRevisionText( $row );
 547                 wfProfileOut( $fname );
 548
 549                 return $text;
 550         }
 551
 552         /**
 553          * Create a new null-revision for insertion into a page's
 554          * history. This will not re-save the text, but simply refer
 555          * to the text from the previous version.
 556          *
 557          * Such revisions can for instance identify page rename
 558          * operations and other such meta-modifications.
 559          *
 560          * @param Database $dbw
 561          * @param int      $pageId ID number of the page to read from
 562          * @param string   $summary
 563          * @param bool     $minor
 564          * @return Revision
 565          */
 566         function &newNullRevision( &$dbw, $pageId, $summary, $minor ) {
 567                 $fname = 'Revision::newNullRevision';
 568                 wfProfileIn( $fname );
 569
 570                 $current = $dbw->selectRow(
 571                         array( 'page', 'revision' ),
 572                         array( 'page_latest', 'rev_text_id' ),
 573                         array(
 574                                 'page_id' => $pageId,
 575                                 'page_latest=rev_id',
 576                                 ),
 577                         $fname );
 578
 579                 if( $current ) {
 580                         $revision = new Revision( array(
 581                                 'page'       => $pageId,
 582                                 'comment'    => $summary,
 583                                 'minor_edit' => $minor,
 584                                 'text_id'    => $current->rev_text_id,
 585                                 ) );
 586                 } else {
 587                         $revision = null;
 588                 }
 589
 590                 wfProfileOut( $fname );
 591                 return $revision;
 592         }
 593
 594 }
 595 ?>