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 $id
  37          * @return Revision
  38          * @access public
  39          */
  40         function &newFromTitle( &$title, $id = 0 ) {
  41                 if( $id ) {
  42                         $matchId = IntVal( $id );
  43                 } else {
  44                         $matchId = 'page_latest';
  45                 }
  46                 return Revision::newFromConds(
  47                         array( "rev_id=$matchId",
  48                                'page_id=rev_page',
  49                                'page_namespace' => $title->getNamespace(),
  50                                'page_title'     => $title->getDbkey() ) );
  51         }
  52
  53         /**
  54          * Load either the current, or a specified, revision
  55          * that's attached to a given page. If not attached
  56          * to that page, will return null.
  57          *
  58          * @param Database $db
  59          * @param int $pageid
  60          * @param int $id
  61          * @return Revision
  62          * @access public
  63          */
  64         function &loadFromPageId( &$db, $pageid, $id = 0 ) {
  65                 if( $id ) {
  66                         $matchId = IntVal( $id );
  67                 } else {
  68                         $matchId = 'page_latest';
  69                 }
  70                 return Revision::loadFromConds(
  71                         $db,
  72                         array( "rev_id=$matchId",
  73                                'rev_page' => IntVal( $pageid ),
  74                                'page_id=rev_page' ) );
  75         }
  76
  77         /**
  78          * Given a set of conditions, fetch a revision.
  79          *
  80          * @param array $conditions
  81          * @return Revision
  82          * @static
  83          * @access private
  84          */
  85         function &newFromConds( $conditions ) {
  86                 $db =& wfGetDB( DB_SLAVE );
  87                 return Revision::loadFromConds( $db, $conditions );
  88         }
  89
  90         /**
  91          * Given a set of conditions, fetch a revision from
  92          * the given database connection.
  93          *
  94          * @param Database $db
  95          * @param array $conditions
  96          * @return Revision
  97          * @static
  98          * @access private
  99          */
 100         function &loadFromConds( &$db, $conditions ) {
 101                 $res =& Revision::fetchFromConds( $db, $conditions );
 102                 if( $res ) {
 103                         $row = $res->fetchObject();
 104                         $res->free();
 105                         if( $row ) {
 106                                 return new Revision( $row );
 107                         }
 108                 }
 109                 return null;
 110         }
 111
 112         /**
 113          * Return a wrapper for a series of database rows to
 114          * fetch all of a given page's revisions in turn.
 115          * Each row can be fed to the constructor to get objects.
 116          *
 117          * @param Title $title
 118          * @return ResultWrapper
 119          * @static
 120          * @access public
 121          */
 122         function &fetchAllRevisions( &$title ) {
 123                 return Revision::fetchFromConds(
 124                         wfGetDB( DB_SLAVE ),
 125                         array( 'page_namespace' => $title->getNamespace(),
 126                                'page_title'     => $title->getDbkey(),
 127                                'page_id=rev_page' ) );
 128         }
 129
 130         /**
 131          * Return a wrapper for a series of database rows to
 132          * fetch all of a given page's revisions in turn.
 133          * Each row can be fed to the constructor to get objects.
 134          *
 135          * @param Title $title
 136          * @return ResultWrapper
 137          * @static
 138          * @access public
 139          */
 140         function &fetchRevision( &$title ) {
 141                 return Revision::fetchFromConds(
 142                         wfGetDB( DB_SLAVE ),
 143                         array( 'rev_id=page_latest',
 144                                'page_namespace' => $title->getNamespace(),
 145                                'page_title'     => $title->getDbkey(),
 146                                'page_id=rev_page' ) );
 147         }
 148
 149         /**
 150          * Given a set of conditions, return a ResultWrapper
 151          * which will return matching database rows with the
 152          * fields necessary to build Revision objects.
 153          *
 154          * @param Database $db
 155          * @param array $conditions
 156          * @return ResultWrapper
 157          * @static
 158          * @access private
 159          */
 160         function &fetchFromConds( &$db, $conditions ) {
 161                 $res = $db->select(
 162                         array( 'page', 'revision' ),
 163                         array( 'page_namespace',
 164                                'page_title',
 165                                'page_latest',
 166                                'rev_id',
 167                                'rev_page',
 168                                'rev_comment',
 169                                'rev_user_text',
 170                                'rev_user',
 171                                'rev_minor_edit',
 172                                'rev_timestamp' ),
 173                         $conditions,
 174                         'Revision::fetchRow' );
 175                 return $db->resultObject( $res );
 176         }
 177
 178         /**
 179          * @param object $row
 180          * @access private
 181          */
 182         function Revision( $row ) {
 183                 if( is_object( $row ) ) {
 184                         $this->mId        = IntVal( $row->rev_id );
 185                         $this->mPage      = IntVal( $row->rev_page );
 186                         $this->mComment   =         $row->rev_comment;
 187                         $this->mUserText  =         $row->rev_user_text;
 188                         $this->mUser      = IntVal( $row->rev_user );
 189                         $this->mMinorEdit = IntVal( $row->rev_minor_edit );
 190                         $this->mTimestamp =         $row->rev_timestamp;
 191
 192                         $this->mCurrent   = ( $row->rev_id == $row->page_latest );
 193                         $this->mTitle     = Title::makeTitle( $row->page_namespace,
 194                                                               $row->page_title );
 195
 196                         if( isset( $row->old_text ) ) {
 197                                 $this->mText  = $this->getRevisionText( $row );
 198                         } else {
 199                                 $this->mText  = null;
 200                         }
 201                 } elseif( is_array( $row ) ) {
 202                         // Build a new revision to be saved...
 203                         global $wgUser;
 204
 205                         $this->mId        = isset( $row['id']         ) ? IntVal( $row['id']         ) : null;
 206                         $this->mPage      = isset( $row['page']       ) ? IntVal( $row['page']       ) : null;
 207                         $this->mComment   = isset( $row['comment']    ) ? StrVal( $row['comment']    ) : null;
 208                         $this->mUserText  = isset( $row['user_text']  ) ? StrVal( $row['user_text']  ) : $wgUser->getName();
 209                         $this->mUser      = isset( $row['user']       ) ? IntVal( $row['user']       ) : $wgUser->getId();
 210                         $this->mMinorEdit = isset( $row['minor_edit'] ) ? IntVal( $row['minor_edit'] ) : 0;
 211                         $this->mTimestamp = isset( $row['timestamp']  ) ? StrVal( $row['timestamp']  ) : wfTimestamp( TS_MW );
 212                         $this->mText      = isset( $row['text']       ) ? StrVal( $row['text']       ) : null;
 213
 214                         $this->mTitle     = null; # Load on demand if needed
 215                         $this->mCurrent   = false;
 216                 } else {
 217                         wfDebugDieBacktrace( 'Revision constructor passed invalid row format.' );
 218                 }
 219         }
 220
 221         /**#@+
 222          * @access public
 223          */
 224
 225         /**
 226          * @return int
 227          */
 228         function getId() {
 229                 return $this->mId;
 230         }
 231
 232         /**
 233          * Returns the title of the page associated with this entry.
 234          * @return Title
 235          */
 236         function &getTitle() {
 237                 if( isset( $this->mTitle ) ) {
 238                         return $this->mTitle;
 239                 }
 240                 $dbr =& wfGetDB( DB_SLAVE );
 241                 $row = $dbr->selectRow(
 242                         array( 'page', 'revision' ),
 243                         array( 'page_namespace', 'page_title' ),
 244                         array( 'page_id=rev_page',
 245                                'rev_id' => $this->mId ),
 246                         'Revision::getTItle' );
 247                 if( $row ) {
 248                         $this->mTitle =& Title::makeTitle( $row->page_namespace,
 249                                                            $row->page_title );
 250                 }
 251                 return $this->mTitle;
 252         }
 253
 254         /**
 255          * @return int
 256          */
 257         function getPage() {
 258                 return $this->mPage;
 259         }
 260
 261         /**
 262          * @return int
 263          */
 264         function getUser() {
 265                 return $this->mUser;
 266         }
 267
 268         /**
 269          * @return string
 270          */
 271         function getUserText() {
 272                 return $this->mUserText;
 273         }
 274
 275         /**
 276          * @return string
 277          */
 278         function getComment() {
 279                 return $this->mComment;
 280         }
 281
 282         /**
 283          * @return bool
 284          */
 285         function isMinor() {
 286                 return (bool)$this->mMinorEdit;
 287         }
 288
 289         /**
 290          * @return string
 291          */
 292         function getText() {
 293                 if( is_null( $this->mText ) ) {
 294                         // Revision text is immutable. Load on demand:
 295                         $this->mText = $this->loadText();
 296                 }
 297                 return $this->mText;
 298         }
 299
 300         /**
 301          * @return string
 302          */
 303         function getTimestamp() {
 304                 return $this->mTimestamp;
 305         }
 306
 307         /**
 308          * @return bool
 309          */
 310         function isCurrent() {
 311                 return $this->mCurrent;
 312         }
 313
 314         /**
 315          * @return Revision
 316          */
 317         function &getPrevious() {
 318                 $prev = $this->mTitle->getPreviousRevisionID( $this->mId );
 319                 return Revision::newFromTitle( $this->mTitle, $prev );
 320         }
 321
 322         /**
 323          * @return Revision
 324          */
 325         function &getNext() {
 326                 $next = $this->mTitle->getNextRevisionID( $this->mId );
 327                 return Revision::newFromTitle( $this->mTitle, $next );
 328         }
 329         /**#@-*/
 330
 331         /**
 332           * Get revision text associated with an old or archive row
 333           * $row is usually an object from wfFetchRow(), both the flags and the text
 334           * field must be included
 335           * @static
 336           * @param integer $row Id of a row
 337           * @param string $prefix table prefix (default 'old_')
 338           * @return string $text|false the text requested
 339           */
 340         function getRevisionText( $row, $prefix = 'old_' ) {
 341                 $fname = 'Revision::getRevisionText';
 342                 wfProfileIn( $fname );
 343
 344                 # Get data
 345                 $textField = $prefix . 'text';
 346                 $flagsField = $prefix . 'flags';
 347
 348                 if( isset( $row->$flagsField ) ) {
 349                         $flags = explode( ',', $row->$flagsField );
 350                 } else {
 351                         $flags = array();
 352                 }
 353
 354                 if( isset( $row->$textField ) ) {
 355                         $text = $row->$textField;
 356                 } else {
 357                         wfProfileOut( $fname );
 358                         return false;
 359                 }
 360
 361                 if( in_array( 'gzip', $flags ) ) {
 362                         # Deal with optional compression of archived pages.
 363                         # This can be done periodically via maintenance/compressOld.php, and
 364                         # as pages are saved if $wgCompressRevisions is set.
 365                         $text = gzinflate( $text );
 366                 }
 367
 368                 if( in_array( 'object', $flags ) ) {
 369                         # Generic compressed storage
 370                         $obj = unserialize( $text );
 371
 372                         # Bugger, corrupted my test database by double-serializing
 373                         if ( !is_object( $obj ) ) {
 374                                 $obj = unserialize( $obj );
 375                         }
 376
 377                         $text = $obj->getText();
 378                 }
 379
 380                 global $wgLegacyEncoding;
 381                 if( $wgLegacyEncoding && !in_array( 'utf-8', $flags ) ) {
 382                         # Old revisions kept around in a legacy encoding?
 383                         # Upconvert on demand.
 384                         global $wgInputEncoding, $wgContLang;
 385                         $text = $wgContLang->iconv( $wgLegacyEncoding, $wgInputEncoding, $text );
 386                 }
 387                 wfProfileOut( $fname );
 388                 return $text;
 389         }
 390
 391         /**
 392          * If $wgCompressRevisions is enabled, we will compress data.
 393          * The input string is modified in place.
 394          * Return value is the flags field: contains 'gzip' if the
 395          * data is compressed, and 'utf-8' if we're saving in UTF-8
 396          * mode.
 397          *
 398          * @static
 399          * @param mixed $text reference to a text
 400          * @return string
 401          */
 402         function compressRevisionText( &$text ) {
 403                 global $wgCompressRevisions, $wgUseLatin1;
 404                 $flags = array();
 405                 if( !$wgUseLatin1 ) {
 406                         # Revisions not marked this way will be converted
 407                         # on load if $wgLegacyCharset is set in the future.
 408                         $flags[] = 'utf-8';
 409                 }
 410                 if( $wgCompressRevisions ) {
 411                         if( function_exists( 'gzdeflate' ) ) {
 412                                 $text = gzdeflate( $text );
 413                                 $flags[] = 'gzip';
 414                         } else {
 415                                 wfDebug( "Revision::compressRevisionText() -- no zlib support, not compressing\n" );
 416                         }
 417                 }
 418                 return implode( ',', $flags );
 419         }
 420
 421         /**
 422          * Insert a new revision into the database, returning the new revision ID
 423          * number on success and dies horribly on failure.
 424          *
 425          * @param Database $dbw
 426          * @return int
 427          */
 428         function insertOn( &$dbw ) {
 429                 $fname = 'Revision::insertOn';
 430                 wfProfileIn( $fname );
 431
 432                 $mungedText = $this->mText;
 433                 $flags = Revision::compressRevisionText( $mungedText );
 434
 435                 # Record the text to the text table
 436                 $old_id = isset( $this->mId )
 437                         ? $this->mId
 438                         : $dbw->nextSequenceValue( 'text_old_id_val' );
 439                 $dbw->insert( 'text',
 440                         array(
 441                                 'old_id'    => $old_id,
 442                                 'old_text'  => $mungedText,
 443                                 'old_flags' => $flags,
 444                         ), $fname
 445                 );
 446                 $revisionId = $dbw->insertId();
 447
 448                 # Record the edit in revisions
 449                 $dbw->insert( 'revision',
 450                         array(
 451                                 'rev_id'         => $revisionId,
 452                                 'rev_page'       => $this->mPage,
 453                                 'rev_comment'    => $this->mComment,
 454                                 'rev_minor_edit' => $this->mMinorEdit ? 1 : 0,
 455                                 'rev_user'       => $this->mUser,
 456                                 'rev_user_text'  => $this->mUserText,
 457                                 'rev_timestamp'  => $dbw->timestamp( $this->mTimestamp ),
 458                         ), $fname
 459                 );
 460
 461                 $this->mId = $revisionId;
 462
 463                 wfProfileOut( $fname );
 464                 return $revisionId;
 465         }
 466
 467         /**
 468          * Lazy-load the revision's text.
 469          * Currently hardcoded to the 'text' table storage engine.
 470          *
 471          * @return string
 472          * @access private
 473          */
 474         function loadText() {
 475                 $fname = 'Revision::loadText';
 476                 wfProfileIn( $fname );
 477
 478                 $dbr =& wfGetDB( DB_SLAVE );
 479                 $row = $dbr->selectRow( 'text',
 480                         array( 'old_text', 'old_flags' ),
 481                         array( 'old_id' => $this->getId() ),
 482                         $fname);
 483
 484                 $text = Revision::getRevisionText( $row );
 485                 wfProfileOut( $fname );
 486
 487                 return $text;
 488         }
 489 }
 490 ?>