includes/installer/DatabaseUpdater.php

   1 <?php
   2 /**
   3  * DBMS-specific updater helper.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup Deployment
  22  */
  23
  24 require_once __DIR__ . '/../../maintenance/Maintenance.php';
  25
  26 /**
  27  * Class for handling database updates. Roughly based off of updaters.inc, with
  28  * a few improvements :)
  29  *
  30  * @ingroup Deployment
  31  * @since 1.17
  32  */
  33 abstract class DatabaseUpdater {
  34
  35         /**
  36          * Array of updates to perform on the database
  37          *
  38          * @var array
  39          */
  40         protected $updates = array();
  41
  42         /**
  43          * Array of updates that were skipped
  44          *
  45          * @var array
  46          */
  47         protected $updatesSkipped = array();
  48
  49         /**
  50          * List of extension-provided database updates
  51          * @var array
  52          */
  53         protected $extensionUpdates = array();
  54
  55         /**
  56          * Handle to the database subclass
  57          *
  58          * @var DatabaseBase
  59          */
  60         protected $db;
  61
  62         protected $shared = false;
  63
  64         /**
  65          * Scripts to run after database update
  66          * Should be a subclass of LoggedUpdateMaintenance
  67          */
  68         protected $postDatabaseUpdateMaintenance = array(
  69                 'DeleteDefaultMessages',
  70                 'PopulateRevisionLength',
  71                 'PopulateRevisionSha1',
  72                 'PopulateImageSha1',
  73                 'FixExtLinksProtocolRelative',
  74                 'PopulateFilearchiveSha1',
  75                 'PopulateBacklinkNamespace'
  76         );
  77
  78         /**
  79          * File handle for SQL output.
  80          *
  81          * @var resource
  82          */
  83         protected $fileHandle = null;
  84
  85         /**
  86          * Flag specifying whether or not to skip schema (e.g. SQL-only) updates.
  87          *
  88          * @var bool
  89          */
  90         protected $skipSchema = false;
  91
  92         /**
  93          * Hold the value of $wgContentHandlerUseDB during the upgrade.
  94          */
  95         protected $holdContentHandlerUseDB = true;
  96
  97         /**
  98          * Constructor
  99          *
 100          * @param DatabaseBase $db To perform updates on
 101          * @param bool $shared Whether to perform updates on shared tables
 102          * @param Maintenance $maintenance Maintenance object which created us
 103          */
 104         protected function __construct( DatabaseBase &$db, $shared, Maintenance $maintenance = null ) {
 105                 $this->db = $db;
 106                 $this->db->setFlag( DBO_DDLMODE ); // For Oracle's handling of schema files
 107                 $this->shared = $shared;
 108                 if ( $maintenance ) {
 109                         $this->maintenance = $maintenance;
 110                         $this->fileHandle = $maintenance->fileHandle;
 111                 } else {
 112                         $this->maintenance = new FakeMaintenance;
 113                 }
 114                 $this->maintenance->setDB( $db );
 115                 $this->initOldGlobals();
 116                 $this->loadExtensions();
 117                 wfRunHooks( 'LoadExtensionSchemaUpdates', array( $this ) );
 118         }
 119
 120         /**
 121          * Initialize all of the old globals. One day this should all become
 122          * something much nicer
 123          */
 124         private function initOldGlobals() {
 125                 global $wgExtNewTables, $wgExtNewFields, $wgExtPGNewFields,
 126                         $wgExtPGAlteredFields, $wgExtNewIndexes, $wgExtModifiedFields;
 127
 128                 # For extensions only, should be populated via hooks
 129                 # $wgDBtype should be checked to specifiy the proper file
 130                 $wgExtNewTables = array(); // table, dir
 131                 $wgExtNewFields = array(); // table, column, dir
 132                 $wgExtPGNewFields = array(); // table, column, column attributes; for PostgreSQL
 133                 $wgExtPGAlteredFields = array(); // table, column, new type, conversion method; for PostgreSQL
 134                 $wgExtNewIndexes = array(); // table, index, dir
 135                 $wgExtModifiedFields = array(); // table, index, dir
 136         }
 137
 138         /**
 139          * Loads LocalSettings.php, if needed, and initialises everything needed for
 140          * LoadExtensionSchemaUpdates hook.
 141          */
 142         private function loadExtensions() {
 143                 if ( !defined( 'MEDIAWIKI_INSTALL' ) ) {
 144                         return; // already loaded
 145                 }
 146                 $vars = Installer::getExistingLocalSettings();
 147                 if ( !$vars ) {
 148                         return; // no LocalSettings found
 149                 }
 150                 if ( !isset( $vars['wgHooks'] ) || !isset( $vars['wgHooks']['LoadExtensionSchemaUpdates'] ) ) {
 151                         return;
 152                 }
 153                 global $wgHooks, $wgAutoloadClasses;
 154                 $wgHooks['LoadExtensionSchemaUpdates'] = $vars['wgHooks']['LoadExtensionSchemaUpdates'];
 155                 $wgAutoloadClasses = $wgAutoloadClasses + $vars['wgAutoloadClasses'];
 156         }
 157
 158         /**
 159          * @param DatabaseBase $db
 160          * @param bool $shared
 161          * @param Maintenance $maintenance
 162          *
 163          * @throws MWException
 164          * @return DatabaseUpdater
 165          */
 166         public static function newForDB( &$db, $shared = false, $maintenance = null ) {
 167                 $type = $db->getType();
 168                 if ( in_array( $type, Installer::getDBTypes() ) ) {
 169                         $class = ucfirst( $type ) . 'Updater';
 170
 171                         return new $class( $db, $shared, $maintenance );
 172                 } else {
 173                         throw new MWException( __METHOD__ . ' called for unsupported $wgDBtype' );
 174                 }
 175         }
 176
 177         /**
 178          * Get a database connection to run updates
 179          *
 180          * @return DatabaseBase
 181          */
 182         public function getDB() {
 183                 return $this->db;
 184         }
 185
 186         /**
 187          * Output some text. If we're running from web, escape the text first.
 188          *
 189          * @param string $str Text to output
 190          */
 191         public function output( $str ) {
 192                 if ( $this->maintenance->isQuiet() ) {
 193                         return;
 194                 }
 195                 global $wgCommandLineMode;
 196                 if ( !$wgCommandLineMode ) {
 197                         $str = htmlspecialchars( $str );
 198                 }
 199                 echo $str;
 200                 flush();
 201         }
 202
 203         /**
 204          * Add a new update coming from an extension. This should be called by
 205          * extensions while executing the LoadExtensionSchemaUpdates hook.
 206          *
 207          * @since 1.17
 208          *
 209          * @param array $update The update to run. Format is the following:
 210          *                first item is the callback function, it also can be a
 211          *                simple string with the name of a function in this class,
 212          *                following elements are parameters to the function.
 213          *                Note that callback functions will receive this object as
 214          *                first parameter.
 215          */
 216         public function addExtensionUpdate( array $update ) {
 217                 $this->extensionUpdates[] = $update;
 218         }
 219
 220         /**
 221          * Convenience wrapper for addExtensionUpdate() when adding a new table (which
 222          * is the most common usage of updaters in an extension)
 223          *
 224          * @since 1.18
 225          *
 226          * @param string $tableName Name of table to create
 227          * @param string $sqlPath Full path to the schema file
 228          */
 229         public function addExtensionTable( $tableName, $sqlPath ) {
 230                 $this->extensionUpdates[] = array( 'addTable', $tableName, $sqlPath, true );
 231         }
 232
 233         /**
 234          * @since 1.19
 235          *
 236          * @param string $tableName
 237          * @param string $indexName
 238          * @param string $sqlPath
 239          */
 240         public function addExtensionIndex( $tableName, $indexName, $sqlPath ) {
 241                 $this->extensionUpdates[] = array( 'addIndex', $tableName, $indexName, $sqlPath, true );
 242         }
 243
 244         /**
 245          *
 246          * @since 1.19
 247          *
 248          * @param string $tableName
 249          * @param string $columnName
 250          * @param string $sqlPath
 251          */
 252         public function addExtensionField( $tableName, $columnName, $sqlPath ) {
 253                 $this->extensionUpdates[] = array( 'addField', $tableName, $columnName, $sqlPath, true );
 254         }
 255
 256         /**
 257          *
 258          * @since 1.20
 259          *
 260          * @param string $tableName
 261          * @param string $columnName
 262          * @param string $sqlPath
 263          */
 264         public function dropExtensionField( $tableName, $columnName, $sqlPath ) {
 265                 $this->extensionUpdates[] = array( 'dropField', $tableName, $columnName, $sqlPath, true );
 266         }
 267
 268         /**
 269          * Drop an index from an extension table
 270          *
 271          * @since 1.21
 272          *
 273          * @param string $tableName The table name
 274          * @param string $indexName The index name
 275          * @param string $sqlPath The path to the SQL change path
 276          */
 277         public function dropExtensionIndex( $tableName, $indexName, $sqlPath ) {
 278                 $this->extensionUpdates[] = array( 'dropIndex', $tableName, $indexName, $sqlPath, true );
 279         }
 280
 281         /**
 282          *
 283          * @since 1.20
 284          *
 285          * @param string $tableName
 286          * @param string $sqlPath
 287          */
 288         public function dropExtensionTable( $tableName, $sqlPath ) {
 289                 $this->extensionUpdates[] = array( 'dropTable', $tableName, $sqlPath, true );
 290         }
 291
 292         /**
 293          * Rename an index on an extension table
 294          *
 295          * @since 1.21
 296          *
 297          * @param string $tableName The table name
 298          * @param string $oldIndexName The old index name
 299          * @param string $newIndexName The new index name
 300          * @param string $sqlPath The path to the SQL change path
 301          * @param bool $skipBothIndexExistWarning Whether to warn if both the old
 302          * and the new indexes exist. [facultative; by default, false]
 303          */
 304         public function renameExtensionIndex( $tableName, $oldIndexName, $newIndexName,
 305                 $sqlPath, $skipBothIndexExistWarning = false
 306         ) {
 307                 $this->extensionUpdates[] = array(
 308                         'renameIndex',
 309                         $tableName,
 310                         $oldIndexName,
 311                         $newIndexName,
 312                         $skipBothIndexExistWarning,
 313                         $sqlPath,
 314                         true
 315                 );
 316         }
 317
 318         /**
 319          * @since 1.21
 320          *
 321          * @param string $tableName The table name
 322          * @param string $fieldName The field to be modified
 323          * @param string $sqlPath The path to the SQL change path
 324          */
 325         public function modifyExtensionField( $tableName, $fieldName, $sqlPath ) {
 326                 $this->extensionUpdates[] = array( 'modifyField', $tableName, $fieldName, $sqlPath, true );
 327         }
 328
 329         /**
 330          *
 331          * @since 1.20
 332          *
 333          * @param string $tableName
 334          * @return bool
 335          */
 336         public function tableExists( $tableName ) {
 337                 return ( $this->db->tableExists( $tableName, __METHOD__ ) );
 338         }
 339
 340         /**
 341          * Add a maintenance script to be run after the database updates are complete.
 342          *
 343          * Script should subclass LoggedUpdateMaintenance
 344          *
 345          * @since 1.19
 346          *
 347          * @param string $class Name of a Maintenance subclass
 348          */
 349         public function addPostDatabaseUpdateMaintenance( $class ) {
 350                 $this->postDatabaseUpdateMaintenance[] = $class;
 351         }
 352
 353         /**
 354          * Get the list of extension-defined updates
 355          *
 356          * @return array
 357          */
 358         protected function getExtensionUpdates() {
 359                 return $this->extensionUpdates;
 360         }
 361
 362         /**
 363          * @since 1.17
 364          *
 365          * @return array
 366          */
 367         public function getPostDatabaseUpdateMaintenance() {
 368                 return $this->postDatabaseUpdateMaintenance;
 369         }
 370
 371         /**
 372          * @since 1.21
 373          *
 374          * Writes the schema updates desired to a file for the DB Admin to run.
 375          * @param array $schemaUpdate
 376          */
 377         private function writeSchemaUpdateFile( $schemaUpdate = array() ) {
 378                 $updates = $this->updatesSkipped;
 379                 $this->updatesSkipped = array();
 380
 381                 foreach ( $updates as $funcList ) {
 382                         $func = $funcList[0];
 383                         $arg = $funcList[1];
 384                         $origParams = $funcList[2];
 385                         call_user_func_array( $func, $arg );
 386                         flush();
 387                         $this->updatesSkipped[] = $origParams;
 388                 }
 389         }
 390
 391         /**
 392          * Do all the updates
 393          *
 394          * @param array $what What updates to perform
 395          */
 396         public function doUpdates( $what = array( 'core', 'extensions', 'stats' ) ) {
 397                 global $wgVersion;
 398
 399                 $this->db->begin( __METHOD__ );
 400                 $what = array_flip( $what );
 401                 $this->skipSchema = isset( $what['noschema'] ) || $this->fileHandle !== null;
 402                 if ( isset( $what['core'] ) ) {
 403                         $this->runUpdates( $this->getCoreUpdateList(), false );
 404                 }
 405                 if ( isset( $what['extensions'] ) ) {
 406                         $this->runUpdates( $this->getOldGlobalUpdates(), false );
 407                         $this->runUpdates( $this->getExtensionUpdates(), true );
 408                 }
 409
 410                 if ( isset( $what['stats'] ) ) {
 411                         $this->checkStats();
 412                 }
 413
 414                 $this->setAppliedUpdates( $wgVersion, $this->updates );
 415
 416                 if ( $this->fileHandle ) {
 417                         $this->skipSchema = false;
 418                         $this->writeSchemaUpdateFile();
 419                         $this->setAppliedUpdates( "$wgVersion-schema", $this->updatesSkipped );
 420                 }
 421
 422                 $this->db->commit( __METHOD__ );
 423         }
 424
 425         /**
 426          * Helper function for doUpdates()
 427          *
 428          * @param array $updates Array of updates to run
 429          * @param bool $passSelf Whether to pass this object we calling external functions
 430          */
 431         private function runUpdates( array $updates, $passSelf ) {
 432                 $updatesDone = array();
 433                 $updatesSkipped = array();
 434                 foreach ( $updates as $params ) {
 435                         $origParams = $params;
 436                         $func = array_shift( $params );
 437                         if ( !is_array( $func ) && method_exists( $this, $func ) ) {
 438                                 $func = array( $this, $func );
 439                         } elseif ( $passSelf ) {
 440                                 array_unshift( $params, $this );
 441                         }
 442                         $ret = call_user_func_array( $func, $params );
 443                         flush();
 444                         if ( $ret !== false ) {
 445                                 $updatesDone[] = $origParams;
 446                         } else {
 447                                 $updatesSkipped[] = array( $func, $params, $origParams );
 448                         }
 449                 }
 450                 $this->updatesSkipped = array_merge( $this->updatesSkipped, $updatesSkipped );
 451                 $this->updates = array_merge( $this->updates, $updatesDone );
 452         }
 453
 454         /**
 455          * @param string $version
 456          * @param array $updates
 457          */
 458         protected function setAppliedUpdates( $version, $updates = array() ) {
 459                 $this->db->clearFlag( DBO_DDLMODE );
 460                 if ( !$this->canUseNewUpdatelog() ) {
 461                         return;
 462                 }
 463                 $key = "updatelist-$version-" . time();
 464                 $this->db->insert( 'updatelog',
 465                         array( 'ul_key' => $key, 'ul_value' => serialize( $updates ) ),
 466                         __METHOD__ );
 467                 $this->db->setFlag( DBO_DDLMODE );
 468         }
 469
 470         /**
 471          * Helper function: check if the given key is present in the updatelog table.
 472          * Obviously, only use this for updates that occur after the updatelog table was
 473          * created!
 474          * @param string $key Name of the key to check for
 475          * @return bool
 476          */
 477         public function updateRowExists( $key ) {
 478                 $row = $this->db->selectRow(
 479                         'updatelog',
 480                         # Bug 65813
 481                         '1 AS X',
 482                         array( 'ul_key' => $key ),
 483                         __METHOD__
 484                 );
 485
 486                 return (bool)$row;
 487         }
 488
 489         /**
 490          * Helper function: Add a key to the updatelog table
 491          * Obviously, only use this for updates that occur after the updatelog table was
 492          * created!
 493          * @param string $key Name of key to insert
 494          * @param string $val [optional] Value to insert along with the key
 495          */
 496         public function insertUpdateRow( $key, $val = null ) {
 497                 $this->db->clearFlag( DBO_DDLMODE );
 498                 $values = array( 'ul_key' => $key );
 499                 if ( $val && $this->canUseNewUpdatelog() ) {
 500                         $values['ul_value'] = $val;
 501                 }
 502                 $this->db->insert( 'updatelog', $values, __METHOD__, 'IGNORE' );
 503                 $this->db->setFlag( DBO_DDLMODE );
 504         }
 505
 506         /**
 507          * Updatelog was changed in 1.17 to have a ul_value column so we can record
 508          * more information about what kind of updates we've done (that's what this
 509          * class does). Pre-1.17 wikis won't have this column, and really old wikis
 510          * might not even have updatelog at all
 511          *
 512          * @return bool
 513          */
 514         protected function canUseNewUpdatelog() {
 515                 return $this->db->tableExists( 'updatelog', __METHOD__ ) &&
 516                         $this->db->fieldExists( 'updatelog', 'ul_value', __METHOD__ );
 517         }
 518
 519         /**
 520          * Returns whether updates should be executed on the database table $name.
 521          * Updates will be prevented if the table is a shared table and it is not
 522          * specified to run updates on shared tables.
 523          *
 524          * @param string $name Table name
 525          * @return bool
 526          */
 527         protected function doTable( $name ) {
 528                 global $wgSharedDB, $wgSharedTables;
 529
 530                 // Don't bother to check $wgSharedTables if there isn't a shared database
 531                 // or the user actually also wants to do updates on the shared database.
 532                 if ( $wgSharedDB === null || $this->shared ) {
 533                         return true;
 534                 }
 535
 536                 if ( in_array( $name, $wgSharedTables ) ) {
 537                         $this->output( "...skipping update to shared table $name.\n" );
 538                         return false;
 539                 } else {
 540                         return true;
 541                 }
 542         }
 543
 544         /**
 545          * Before 1.17, we used to handle updates via stuff like
 546          * $wgExtNewTables/Fields/Indexes. This is nasty :) We refactored a lot
 547          * of this in 1.17 but we want to remain back-compatible for a while. So
 548          * load up these old global-based things into our update list.
 549          *
 550          * @return array
 551          */
 552         protected function getOldGlobalUpdates() {
 553                 global $wgExtNewFields, $wgExtNewTables, $wgExtModifiedFields,
 554                         $wgExtNewIndexes;
 555
 556                 $updates = array();
 557
 558                 foreach ( $wgExtNewTables as $tableRecord ) {
 559                         $updates[] = array(
 560                                 'addTable', $tableRecord[0], $tableRecord[1], true
 561                         );
 562                 }
 563
 564                 foreach ( $wgExtNewFields as $fieldRecord ) {
 565                         $updates[] = array(
 566                                 'addField', $fieldRecord[0], $fieldRecord[1],
 567                                 $fieldRecord[2], true
 568                         );
 569                 }
 570
 571                 foreach ( $wgExtNewIndexes as $fieldRecord ) {
 572                         $updates[] = array(
 573                                 'addIndex', $fieldRecord[0], $fieldRecord[1],
 574                                 $fieldRecord[2], true
 575                         );
 576                 }
 577
 578                 foreach ( $wgExtModifiedFields as $fieldRecord ) {
 579                         $updates[] = array(
 580                                 'modifyField', $fieldRecord[0], $fieldRecord[1],
 581                                 $fieldRecord[2], true
 582                         );
 583                 }
 584
 585                 return $updates;
 586         }
 587
 588         /**
 589          * Get an array of updates to perform on the database. Should return a
 590          * multi-dimensional array. The main key is the MediaWiki version (1.12,
 591          * 1.13...) with the values being arrays of updates, identical to how
 592          * updaters.inc did it (for now)
 593          *
 594          * @return array
 595          */
 596         abstract protected function getCoreUpdateList();
 597
 598         /**
 599          * Append an SQL fragment to the open file handle.
 600          *
 601          * @param string $filename File name to open
 602          */
 603         public function copyFile( $filename ) {
 604                 $this->db->sourceFile( $filename, false, false, false,
 605                         array( $this, 'appendLine' )
 606                 );
 607         }
 608
 609         /**
 610          * Append a line to the open filehandle.  The line is assumed to
 611          * be a complete SQL statement.
 612          *
 613          * This is used as a callback for for sourceLine().
 614          *
 615          * @param string $line Text to append to the file
 616          * @return bool False to skip actually executing the file
 617          * @throws MWException
 618          */
 619         public function appendLine( $line ) {
 620                 $line = rtrim( $line ) . ";\n";
 621                 if ( fwrite( $this->fileHandle, $line ) === false ) {
 622                         throw new MWException( "trouble writing file" );
 623                 }
 624
 625                 return false;
 626         }
 627
 628         /**
 629          * Applies a SQL patch
 630          *
 631          * @param string $path Path to the patch file
 632          * @param bool $isFullPath Whether to treat $path as a relative or not
 633          * @param string $msg Description of the patch
 634          * @return bool False if patch is skipped.
 635          */
 636         protected function applyPatch( $path, $isFullPath = false, $msg = null ) {
 637                 if ( $msg === null ) {
 638                         $msg = "Applying $path patch";
 639                 }
 640                 if ( $this->skipSchema ) {
 641                         $this->output( "...skipping schema change ($msg).\n" );
 642
 643                         return false;
 644                 }
 645
 646                 $this->output( "$msg ..." );
 647
 648                 if ( !$isFullPath ) {
 649                         $path = $this->db->patchPath( $path );
 650                 }
 651                 if ( $this->fileHandle !== null ) {
 652                         $this->copyFile( $path );
 653                 } else {
 654                         $this->db->sourceFile( $path );
 655                 }
 656                 $this->output( "done.\n" );
 657
 658                 return true;
 659         }
 660
 661         /**
 662          * Add a new table to the database
 663          *
 664          * @param string $name Name of the new table
 665          * @param string $patch Path to the patch file
 666          * @param bool $fullpath Whether to treat $patch path as a relative or not
 667          * @return bool False if this was skipped because schema changes are skipped
 668          */
 669         protected function addTable( $name, $patch, $fullpath = false ) {
 670                 if ( !$this->doTable( $name ) ) {
 671                         return true;
 672                 }
 673
 674                 if ( $this->db->tableExists( $name, __METHOD__ ) ) {
 675                         $this->output( "...$name table already exists.\n" );
 676                 } else {
 677                         return $this->applyPatch( $patch, $fullpath, "Creating $name table" );
 678                 }
 679
 680                 return true;
 681         }
 682
 683         /**
 684          * Add a new field to an existing table
 685          *
 686          * @param string $table Name of the table to modify
 687          * @param string $field Name of the new field
 688          * @param string $patch Path to the patch file
 689          * @param bool $fullpath Whether to treat $patch path as a relative or not
 690          * @return bool False if this was skipped because schema changes are skipped
 691          */
 692         protected function addField( $table, $field, $patch, $fullpath = false ) {
 693                 if ( !$this->doTable( $table ) ) {
 694                         return true;
 695                 }
 696
 697                 if ( !$this->db->tableExists( $table, __METHOD__ ) ) {
 698                         $this->output( "...$table table does not exist, skipping new field patch.\n" );
 699                 } elseif ( $this->db->fieldExists( $table, $field, __METHOD__ ) ) {
 700                         $this->output( "...have $field field in $table table.\n" );
 701                 } else {
 702                         return $this->applyPatch( $patch, $fullpath, "Adding $field field to table $table" );
 703                 }
 704
 705                 return true;
 706         }
 707
 708         /**
 709          * Add a new index to an existing table
 710          *
 711          * @param string $table Name of the table to modify
 712          * @param string $index Name of the new index
 713          * @param string $patch Path to the patch file
 714          * @param bool $fullpath Whether to treat $patch path as a relative or not
 715          * @return bool False if this was skipped because schema changes are skipped
 716          */
 717         protected function addIndex( $table, $index, $patch, $fullpath = false ) {
 718                 if ( !$this->doTable( $table ) ) {
 719                         return true;
 720                 }
 721
 722                 if ( !$this->db->tableExists( $table, __METHOD__ ) ) {
 723                         $this->output( "...skipping: '$table' table doesn't exist yet.\n" );
 724                 } elseif ( $this->db->indexExists( $table, $index, __METHOD__ ) ) {
 725                         $this->output( "...index $index already set on $table table.\n" );
 726                 } else {
 727                         return $this->applyPatch( $patch, $fullpath, "Adding index $index to table $table" );
 728                 }
 729
 730                 return true;
 731         }
 732
 733         /**
 734          * Drop a field from an existing table
 735          *
 736          * @param string $table Name of the table to modify
 737          * @param string $field Name of the old field
 738          * @param string $patch Path to the patch file
 739          * @param bool $fullpath Whether to treat $patch path as a relative or not
 740          * @return bool False if this was skipped because schema changes are skipped
 741          */
 742         protected function dropField( $table, $field, $patch, $fullpath = false ) {
 743                 if ( !$this->doTable( $table ) ) {
 744                         return true;
 745                 }
 746
 747                 if ( $this->db->fieldExists( $table, $field, __METHOD__ ) ) {
 748                         return $this->applyPatch( $patch, $fullpath, "Table $table contains $field field. Dropping" );
 749                 } else {
 750                         $this->output( "...$table table does not contain $field field.\n" );
 751                 }
 752
 753                 return true;
 754         }
 755
 756         /**
 757          * Drop an index from an existing table
 758          *
 759          * @param string $table Name of the table to modify
 760          * @param string $index Name of the index
 761          * @param string $patch Path to the patch file
 762          * @param bool $fullpath Whether to treat $patch path as a relative or not
 763          * @return bool False if this was skipped because schema changes are skipped
 764          */
 765         protected function dropIndex( $table, $index, $patch, $fullpath = false ) {
 766                 if ( !$this->doTable( $table ) ) {
 767                         return true;
 768                 }
 769
 770                 if ( $this->db->indexExists( $table, $index, __METHOD__ ) ) {
 771                         return $this->applyPatch( $patch, $fullpath, "Dropping $index index from table $table" );
 772                 } else {
 773                         $this->output( "...$index key doesn't exist.\n" );
 774                 }
 775
 776                 return true;
 777         }
 778
 779         /**
 780          * Rename an index from an existing table
 781          *
 782          * @param string $table Name of the table to modify
 783          * @param string $oldIndex Old name of the index
 784          * @param string $newIndex New name of the index
 785          * @param bool $skipBothIndexExistWarning Whether to warn if both the
 786          * old and the new indexes exist.
 787          * @param string $patch Path to the patch file
 788          * @param bool $fullpath Whether to treat $patch path as a relative or not
 789          * @return bool False if this was skipped because schema changes are skipped
 790          */
 791         protected function renameIndex( $table, $oldIndex, $newIndex,
 792                 $skipBothIndexExistWarning, $patch, $fullpath = false
 793         ) {
 794                 if ( !$this->doTable( $table ) ) {
 795                         return true;
 796                 }
 797
 798                 // First requirement: the table must exist
 799                 if ( !$this->db->tableExists( $table, __METHOD__ ) ) {
 800                         $this->output( "...skipping: '$table' table doesn't exist yet.\n" );
 801
 802                         return true;
 803                 }
 804
 805                 // Second requirement: the new index must be missing
 806                 if ( $this->db->indexExists( $table, $newIndex, __METHOD__ ) ) {
 807                         $this->output( "...index $newIndex already set on $table table.\n" );
 808                         if ( !$skipBothIndexExistWarning &&
 809                                 $this->db->indexExists( $table, $oldIndex, __METHOD__ )
 810                         ) {
 811                                 $this->output( "...WARNING: $oldIndex still exists, despite it has " .
 812                                         "been renamed into $newIndex (which also exists).\n" .
 813                                         "            $oldIndex should be manually removed if not needed anymore.\n" );
 814                         }
 815
 816                         return true;
 817                 }
 818
 819                 // Third requirement: the old index must exist
 820                 if ( !$this->db->indexExists( $table, $oldIndex, __METHOD__ ) ) {
 821                         $this->output( "...skipping: index $oldIndex doesn't exist.\n" );
 822
 823                         return true;
 824                 }
 825
 826                 // Requirements have been satisfied, patch can be applied
 827                 return $this->applyPatch(
 828                         $patch,
 829                         $fullpath,
 830                         "Renaming index $oldIndex into $newIndex to table $table"
 831                 );
 832         }
 833
 834         /**
 835          * If the specified table exists, drop it, or execute the
 836          * patch if one is provided.
 837          *
 838          * Public @since 1.20
 839          *
 840          * @param string $table Table to drop.
 841          * @param string|bool $patch String of patch file that will drop the table. Default: false.
 842          * @param bool $fullpath Whether $patch is a full path. Default: false.
 843          * @return bool False if this was skipped because schema changes are skipped
 844          */
 845         public function dropTable( $table, $patch = false, $fullpath = false ) {
 846                 if ( !$this->doTable( $table ) ) {
 847                         return true;
 848                 }
 849
 850                 if ( $this->db->tableExists( $table, __METHOD__ ) ) {
 851                         $msg = "Dropping table $table";
 852
 853                         if ( $patch === false ) {
 854                                 $this->output( "$msg ..." );
 855                                 $this->db->dropTable( $table, __METHOD__ );
 856                                 $this->output( "done.\n" );
 857                         } else {
 858                                 return $this->applyPatch( $patch, $fullpath, $msg );
 859                         }
 860                 } else {
 861                         $this->output( "...$table doesn't exist.\n" );
 862                 }
 863
 864                 return true;
 865         }
 866
 867         /**
 868          * Modify an existing field
 869          *
 870          * @param string $table Name of the table to which the field belongs
 871          * @param string $field Name of the field to modify
 872          * @param string $patch Path to the patch file
 873          * @param bool $fullpath Whether to treat $patch path as a relative or not
 874          * @return bool False if this was skipped because schema changes are skipped
 875          */
 876         public function modifyField( $table, $field, $patch, $fullpath = false ) {
 877                 if ( !$this->doTable( $table ) ) {
 878                         return true;
 879                 }
 880
 881                 $updateKey = "$table-$field-$patch";
 882                 if ( !$this->db->tableExists( $table, __METHOD__ ) ) {
 883                         $this->output( "...$table table does not exist, skipping modify field patch.\n" );
 884                 } elseif ( !$this->db->fieldExists( $table, $field, __METHOD__ ) ) {
 885                         $this->output( "...$field field does not exist in $table table, " .
 886                                 "skipping modify field patch.\n" );
 887                 } elseif ( $this->updateRowExists( $updateKey ) ) {
 888                         $this->output( "...$field in table $table already modified by patch $patch.\n" );
 889                 } else {
 890                         $this->insertUpdateRow( $updateKey );
 891
 892                         return $this->applyPatch( $patch, $fullpath, "Modifying $field field of table $table" );
 893                 }
 894
 895                 return true;
 896         }
 897
 898         /**
 899          * Purge the objectcache table
 900          */
 901         public function purgeCache() {
 902                 global $wgLocalisationCacheConf;
 903                 # We can't guarantee that the user will be able to use TRUNCATE,
 904                 # but we know that DELETE is available to us
 905                 $this->output( "Purging caches..." );
 906                 $this->db->delete( 'objectcache', '*', __METHOD__ );
 907                 if ( $wgLocalisationCacheConf['manualRecache'] ) {
 908                         $this->rebuildLocalisationCache();
 909                 }
 910                 MessageBlobStore::clear();
 911                 $this->output( "done.\n" );
 912         }
 913
 914         /**
 915          * Check the site_stats table is not properly populated.
 916          */
 917         protected function checkStats() {
 918                 $this->output( "...site_stats is populated..." );
 919                 $row = $this->db->selectRow( 'site_stats', '*', array( 'ss_row_id' => 1 ), __METHOD__ );
 920                 if ( $row === false ) {
 921                         $this->output( "data is missing! rebuilding...\n" );
 922                 } elseif ( isset( $row->site_stats ) && $row->ss_total_pages == -1 ) {
 923                         $this->output( "missing ss_total_pages, rebuilding...\n" );
 924                 } else {
 925                         $this->output( "done.\n" );
 926
 927                         return;
 928                 }
 929                 SiteStatsInit::doAllAndCommit( $this->db );
 930         }
 931
 932         # Common updater functions
 933
 934         /**
 935          * Sets the number of active users in the site_stats table
 936          */
 937         protected function doActiveUsersInit() {
 938                 $activeUsers = $this->db->selectField( 'site_stats', 'ss_active_users', false, __METHOD__ );
 939                 if ( $activeUsers == -1 ) {
 940                         $activeUsers = $this->db->selectField( 'recentchanges',
 941                                 'COUNT( DISTINCT rc_user_text )',
 942                                 array( 'rc_user != 0', 'rc_bot' => 0, "rc_log_type != 'newusers'" ), __METHOD__
 943                         );
 944                         $this->db->update( 'site_stats',
 945                                 array( 'ss_active_users' => intval( $activeUsers ) ),
 946                                 array( 'ss_row_id' => 1 ), __METHOD__, array( 'LIMIT' => 1 )
 947                         );
 948                 }
 949                 $this->output( "...ss_active_users user count set...\n" );
 950         }
 951
 952         /**
 953          * Populates the log_user_text field in the logging table
 954          */
 955         protected function doLogUsertextPopulation() {
 956                 if ( !$this->updateRowExists( 'populate log_usertext' ) ) {
 957                         $this->output(
 958                                 "Populating log_user_text field, printing progress markers. For large\n" .
 959                                 "databases, you may want to hit Ctrl-C and do this manually with\n" .
 960                                 "maintenance/populateLogUsertext.php.\n"
 961                         );
 962
 963                         $task = $this->maintenance->runChild( 'PopulateLogUsertext' );
 964                         $task->execute();
 965                         $this->output( "done.\n" );
 966                 }
 967         }
 968
 969         /**
 970          * Migrate log params to new table and index for searching
 971          */
 972         protected function doLogSearchPopulation() {
 973                 if ( !$this->updateRowExists( 'populate log_search' ) ) {
 974                         $this->output(
 975                                 "Populating log_search table, printing progress markers. For large\n" .
 976                                 "databases, you may want to hit Ctrl-C and do this manually with\n" .
 977                                 "maintenance/populateLogSearch.php.\n" );
 978
 979                         $task = $this->maintenance->runChild( 'PopulateLogSearch' );
 980                         $task->execute();
 981                         $this->output( "done.\n" );
 982                 }
 983         }
 984
 985         /**
 986          * Updates the timestamps in the transcache table
 987          */
 988         protected function doUpdateTranscacheField() {
 989                 if ( $this->updateRowExists( 'convert transcache field' ) ) {
 990                         $this->output( "...transcache tc_time already converted.\n" );
 991
 992                         return true;
 993                 }
 994
 995                 return $this->applyPatch( 'patch-tc-timestamp.sql', false,
 996                         "Converting tc_time from UNIX epoch to MediaWiki timestamp" );
 997         }
 998
 999         /**
1000          * Update CategoryLinks collation
1001          */
1002         protected function doCollationUpdate() {
1003                 global $wgCategoryCollation;
1004                 if ( $this->db->fieldExists( 'categorylinks', 'cl_collation', __METHOD__ ) ) {
1005                         if ( $this->db->selectField(
1006                                 'categorylinks',
1007                                 'COUNT(*)',
1008                                 'cl_collation != ' . $this->db->addQuotes( $wgCategoryCollation ),
1009                                 __METHOD__
1010                                 ) == 0
1011                         ) {
1012                                 $this->output( "...collations up-to-date.\n" );
1013
1014                                 return;
1015                         }
1016
1017                         $this->output( "Updating category collations..." );
1018                         $task = $this->maintenance->runChild( 'UpdateCollation' );
1019                         $task->execute();
1020                         $this->output( "...done.\n" );
1021                 }
1022         }
1023
1024         /**
1025          * Migrates user options from the user table blob to user_properties
1026          */
1027         protected function doMigrateUserOptions() {
1028                 if ( $this->db->tableExists( 'user_properties' ) ) {
1029                         $cl = $this->maintenance->runChild( 'ConvertUserOptions', 'convertUserOptions.php' );
1030                         $cl->execute();
1031                         $this->output( "done.\n" );
1032                 }
1033         }
1034
1035         /**
1036          * Rebuilds the localisation cache
1037          */
1038         protected function rebuildLocalisationCache() {
1039                 /**
1040                  * @var $cl RebuildLocalisationCache
1041                  */
1042                 $cl = $this->maintenance->runChild( 'RebuildLocalisationCache', 'rebuildLocalisationCache.php' );
1043                 $this->output( "Rebuilding localisation cache...\n" );
1044                 $cl->setForce();
1045                 $cl->execute();
1046                 $this->output( "done.\n" );
1047         }
1048
1049         /**
1050          * Turns off content handler fields during parts of the upgrade
1051          * where they aren't available.
1052          */
1053         protected function disableContentHandlerUseDB() {
1054                 global $wgContentHandlerUseDB;
1055
1056                 if ( $wgContentHandlerUseDB ) {
1057                         $this->output( "Turning off Content Handler DB fields for this part of upgrade.\n" );
1058                         $this->holdContentHandlerUseDB = $wgContentHandlerUseDB;
1059                         $wgContentHandlerUseDB = false;
1060                 }
1061         }
1062
1063         /**
1064          * Turns content handler fields back on.
1065          */
1066         protected function enableContentHandlerUseDB() {
1067                 global $wgContentHandlerUseDB;
1068
1069                 if ( $this->holdContentHandlerUseDB ) {
1070                         $this->output( "Content Handler DB fields should be usable now.\n" );
1071                         $wgContentHandlerUseDB = $this->holdContentHandlerUseDB;
1072                 }
1073         }
1074 }