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         );
  76
  77         /**
  78          * File handle for SQL output.
  79          *
  80          * @var Filehandle
  81          */
  82         protected $fileHandle = null;
  83
  84         /**
  85          * Flag specifying whether or not to skip schema (e.g. SQL-only) updates.
  86          *
  87          * @var bool
  88          */
  89         protected $skipSchema = false;
  90
  91         /**
  92          * Constructor
  93          *
  94          * @param $db DatabaseBase object to perform updates on
  95          * @param $shared bool Whether to perform updates on shared tables
  96          * @param $maintenance Maintenance Maintenance object which created us
  97          */
  98         protected function __construct( DatabaseBase &$db, $shared, Maintenance $maintenance = null ) {
  99                 $this->db = $db;
 100                 $this->db->setFlag( DBO_DDLMODE ); // For Oracle's handling of schema files
 101                 $this->shared = $shared;
 102                 if ( $maintenance ) {
 103                         $this->maintenance = $maintenance;
 104                         $this->fileHandle = $maintenance->fileHandle;
 105                 } else {
 106                         $this->maintenance = new FakeMaintenance;
 107                 }
 108                 $this->maintenance->setDB( $db );
 109                 $this->initOldGlobals();
 110                 $this->loadExtensions();
 111                 wfRunHooks( 'LoadExtensionSchemaUpdates', array( $this ) );
 112         }
 113
 114         /**
 115          * Initialize all of the old globals. One day this should all become
 116          * something much nicer
 117          */
 118         private function initOldGlobals() {
 119                 global $wgExtNewTables, $wgExtNewFields, $wgExtPGNewFields,
 120                         $wgExtPGAlteredFields, $wgExtNewIndexes, $wgExtModifiedFields;
 121
 122                 # For extensions only, should be populated via hooks
 123                 # $wgDBtype should be checked to specifiy the proper file
 124                 $wgExtNewTables = array(); // table, dir
 125                 $wgExtNewFields = array(); // table, column, dir
 126                 $wgExtPGNewFields = array(); // table, column, column attributes; for PostgreSQL
 127                 $wgExtPGAlteredFields = array(); // table, column, new type, conversion method; for PostgreSQL
 128                 $wgExtNewIndexes = array(); // table, index, dir
 129                 $wgExtModifiedFields = array(); // table, index, dir
 130         }
 131
 132         /**
 133          * Loads LocalSettings.php, if needed, and initialises everything needed for LoadExtensionSchemaUpdates hook
 134          */
 135         private function loadExtensions() {
 136                 if ( !defined( 'MEDIAWIKI_INSTALL' ) ) {
 137                         return; // already loaded
 138                 }
 139                 $vars = Installer::getExistingLocalSettings();
 140                 if ( !$vars ) {
 141                         return; // no LocalSettings found
 142                 }
 143                 if ( !isset( $vars['wgHooks'] ) || !isset( $vars['wgHooks']['LoadExtensionSchemaUpdates'] ) ) {
 144                         return;
 145                 }
 146                 global $wgHooks, $wgAutoloadClasses;
 147                 $wgHooks['LoadExtensionSchemaUpdates'] = $vars['wgHooks']['LoadExtensionSchemaUpdates'];
 148                 $wgAutoloadClasses = $wgAutoloadClasses + $vars['wgAutoloadClasses'];
 149         }
 150
 151         /**
 152          * @throws MWException
 153          * @param DatabaseBase $db
 154          * @param bool $shared
 155          * @param null $maintenance
 156          * @return DatabaseUpdater
 157          */
 158         public static function newForDB( &$db, $shared = false, $maintenance = null ) {
 159                 $type = $db->getType();
 160                 if( in_array( $type, Installer::getDBTypes() ) ) {
 161                         $class = ucfirst( $type ) . 'Updater';
 162                         return new $class( $db, $shared, $maintenance );
 163                 } else {
 164                         throw new MWException( __METHOD__ . ' called for unsupported $wgDBtype' );
 165                 }
 166         }
 167
 168         /**
 169          * Get a database connection to run updates
 170          *
 171          * @return DatabaseBase
 172          */
 173         public function getDB() {
 174                 return $this->db;
 175         }
 176
 177         /**
 178          * Output some text. If we're running from web, escape the text first.
 179          *
 180          * @param $str String: Text to output
 181          */
 182         public function output( $str ) {
 183                 if ( $this->maintenance->isQuiet() ) {
 184                         return;
 185                 }
 186                 global $wgCommandLineMode;
 187                 if( !$wgCommandLineMode ) {
 188                         $str = htmlspecialchars( $str );
 189                 }
 190                 echo $str;
 191                 flush();
 192         }
 193
 194         /**
 195          * Add a new update coming from an extension. This should be called by
 196          * extensions while executing the LoadExtensionSchemaUpdates hook.
 197          *
 198          * @since 1.17
 199          *
 200          * @param $update Array: the update to run. Format is the following:
 201          *                first item is the callback function, it also can be a
 202          *                simple string with the name of a function in this class,
 203          *                following elements are parameters to the function.
 204          *                Note that callback functions will receive this object as
 205          *                first parameter.
 206          */
 207         public function addExtensionUpdate( array $update ) {
 208                 $this->extensionUpdates[] = $update;
 209         }
 210
 211         /**
 212          * Convenience wrapper for addExtensionUpdate() when adding a new table (which
 213          * is the most common usage of updaters in an extension)
 214          *
 215          * @since 1.18
 216          *
 217          * @param $tableName String Name of table to create
 218          * @param $sqlPath String Full path to the schema file
 219          */
 220         public function addExtensionTable( $tableName, $sqlPath ) {
 221                 $this->extensionUpdates[] = array( 'addTable', $tableName, $sqlPath, true );
 222         }
 223
 224         /**
 225          * @since 1.19
 226          *
 227          * @param $tableName string
 228          * @param $indexName string
 229          * @param $sqlPath string
 230          */
 231         public function addExtensionIndex( $tableName, $indexName, $sqlPath ) {
 232                 $this->extensionUpdates[] = array( 'addIndex', $tableName, $indexName, $sqlPath, true );
 233         }
 234
 235         /**
 236          *
 237          * @since 1.19
 238          *
 239          * @param $tableName string
 240          * @param $columnName string
 241          * @param $sqlPath string
 242          */
 243         public function addExtensionField( $tableName, $columnName, $sqlPath ) {
 244                 $this->extensionUpdates[] = array( 'addField', $tableName, $columnName, $sqlPath, true );
 245         }
 246
 247         /**
 248          *
 249          * @since 1.20
 250          *
 251          * @param $tableName string
 252          * @param $columnName string
 253          * @param $sqlPath string
 254          */
 255         public function dropExtensionField( $tableName, $columnName, $sqlPath ) {
 256                 $this->extensionUpdates[] = array( 'dropField', $tableName, $columnName, $sqlPath, true );
 257         }
 258
 259         /**
 260          *
 261          * @since 1.20
 262          *
 263          * @param $tableName string
 264          * @param $sqlPath string
 265          */
 266         public function dropExtensionTable( $tableName, $sqlPath ) {
 267                 $this->extensionUpdates[] = array( 'dropTable', $tableName, $sqlPath, true );
 268         }
 269
 270         /**
 271          *
 272          * @since 1.20
 273          *
 274          * @param $tableName string
 275          * @return bool
 276          */
 277         public function tableExists( $tableName ) {
 278                 return ( $this->db->tableExists( $tableName, __METHOD__ ) );
 279         }
 280
 281         /**
 282          * Add a maintenance script to be run after the database updates are complete.
 283          *
 284          * Script should subclass LoggedUpdateMaintenance
 285          *
 286          * @since 1.19
 287          *
 288          * @param $class string Name of a Maintenance subclass
 289          */
 290         public function addPostDatabaseUpdateMaintenance( $class ) {
 291                 $this->postDatabaseUpdateMaintenance[] = $class;
 292         }
 293
 294         /**
 295          * Get the list of extension-defined updates
 296          *
 297          * @return Array
 298          */
 299         protected function getExtensionUpdates() {
 300                 return $this->extensionUpdates;
 301         }
 302
 303         /**
 304          * @since 1.17
 305          *
 306          * @return array
 307          */
 308         public function getPostDatabaseUpdateMaintenance() {
 309                 return $this->postDatabaseUpdateMaintenance;
 310         }
 311
 312         /**
 313          * @since 1.21
 314          *
 315          * Writes the schema updates desired to a file for the DB Admin to run.
 316          */
 317         private function writeSchemaUpdateFile( $schemaUpdate = array() ) {
 318                 $updates = $this->updatesSkipped;
 319                 $this->updatesSkipped = array();
 320
 321                 foreach( $updates as $funcList ) {
 322                         $func = $funcList[0];
 323                         $arg = $funcList[1];
 324                         $origParams = $funcList[2];
 325                         $ret = call_user_func_array( $func, $arg );
 326                         flush();
 327                         $this->updatesSkipped[] = $origParams;
 328                 }
 329         }
 330
 331         /**
 332          * Do all the updates
 333          *
 334          * @param $what Array: what updates to perform
 335          */
 336         public function doUpdates( $what = array( 'core', 'extensions', 'stats' ) ) {
 337                 global $wgVersion, $wgLocalisationCacheConf;
 338
 339                 $this->db->begin( __METHOD__ );
 340                 $what = array_flip( $what );
 341                 $this->skipSchema = isset( $what['noschema'] ) || $this->fileHandle !== null;
 342                 if ( isset( $what['core'] ) ) {
 343                         $this->runUpdates( $this->getCoreUpdateList(), false );
 344                 }
 345                 if ( isset( $what['extensions'] ) ) {
 346                         $this->runUpdates( $this->getOldGlobalUpdates(), false );
 347                         $this->runUpdates( $this->getExtensionUpdates(), true );
 348                 }
 349
 350                 if ( isset( $what['stats'] ) ) {
 351                         $this->checkStats();
 352                 }
 353
 354                 if ( isset( $what['purge'] ) ) {
 355                         $this->purgeCache();
 356
 357                         if ( $wgLocalisationCacheConf['manualRecache'] ) {
 358                                 $this->rebuildLocalisationCache();
 359                         }
 360                 }
 361
 362                 $this->setAppliedUpdates( $wgVersion, $this->updates );
 363
 364                 if( $this->fileHandle ) {
 365                         $this->skipSchema = false;
 366                         $this->writeSchemaUpdateFile( );
 367                         $this->setAppliedUpdates( "$wgVersion-schema", $this->updatesSkipped );
 368                 }
 369
 370                 $this->db->commit( __METHOD__ );
 371         }
 372
 373         /**
 374          * Helper function for doUpdates()
 375          *
 376          * @param $updates Array of updates to run
 377          * @param $passSelf Boolean: whether to pass this object we calling external
 378          *                  functions
 379          */
 380         private function runUpdates( array $updates, $passSelf ) {
 381                 $updatesDone = array();
 382                 $updatesSkipped = array();
 383                 foreach ( $updates as $params ) {
 384                         $origParams = $params;
 385                         $func = array_shift( $params );
 386                         if( !is_array( $func ) && method_exists( $this, $func ) ) {
 387                                 $func = array( $this, $func );
 388                         } elseif ( $passSelf ) {
 389                                 array_unshift( $params, $this );
 390                         }
 391                         $ret = call_user_func_array( $func, $params );
 392                         flush();
 393                         if( $ret !== false ) {
 394                                 $updatesDone[] = $origParams;
 395                         } else {
 396                                 $updatesSkipped[] = array( $func, $params, $origParams );
 397                         }
 398                 }
 399                 $this->updatesSkipped = array_merge( $this->updatesSkipped, $updatesSkipped );
 400                 $this->updates = array_merge( $this->updates, $updatesDone );
 401         }
 402
 403         /**
 404          * @param $version
 405          * @param $updates array
 406          */
 407         protected function setAppliedUpdates( $version, $updates = array() ) {
 408                 $this->db->clearFlag( DBO_DDLMODE );
 409                 if( !$this->canUseNewUpdatelog() ) {
 410                         return;
 411                 }
 412                 $key = "updatelist-$version-" . time();
 413                 $this->db->insert( 'updatelog',
 414                         array( 'ul_key' => $key, 'ul_value' => serialize( $updates ) ),
 415                          __METHOD__ );
 416                 $this->db->setFlag( DBO_DDLMODE );
 417         }
 418
 419         /**
 420          * Helper function: check if the given key is present in the updatelog table.
 421          * Obviously, only use this for updates that occur after the updatelog table was
 422          * created!
 423          * @param $key String Name of the key to check for
 424          *
 425          * @return bool
 426          */
 427         public function updateRowExists( $key ) {
 428                 $row = $this->db->selectRow(
 429                         'updatelog',
 430                         '1',
 431                         array( 'ul_key' => $key ),
 432                         __METHOD__
 433                 );
 434                 return (bool)$row;
 435         }
 436
 437         /**
 438          * Helper function: Add a key to the updatelog table
 439          * Obviously, only use this for updates that occur after the updatelog table was
 440          * created!
 441          * @param $key String Name of key to insert
 442          * @param $val String [optional] value to insert along with the key
 443          */
 444         public function insertUpdateRow( $key, $val = null ) {
 445                 $this->db->clearFlag( DBO_DDLMODE );
 446                 $values = array( 'ul_key' => $key );
 447                 if( $val && $this->canUseNewUpdatelog() ) {
 448                         $values['ul_value'] = $val;
 449                 }
 450                 $this->db->insert( 'updatelog', $values, __METHOD__, 'IGNORE' );
 451                 $this->db->setFlag( DBO_DDLMODE );
 452         }
 453
 454         /**
 455          * Updatelog was changed in 1.17 to have a ul_value column so we can record
 456          * more information about what kind of updates we've done (that's what this
 457          * class does). Pre-1.17 wikis won't have this column, and really old wikis
 458          * might not even have updatelog at all
 459          *
 460          * @return boolean
 461          */
 462         protected function canUseNewUpdatelog() {
 463                 return $this->db->tableExists( 'updatelog', __METHOD__ ) &&
 464                         $this->db->fieldExists( 'updatelog', 'ul_value', __METHOD__ );
 465         }
 466
 467         /**
 468          * Returns whether updates should be executed on the database table $name.
 469          * Updates will be prevented if the table is a shared table and it is not
 470          * specified to run updates on shared tables.
 471          *
 472          * @param $name String table name
 473          * @return bool
 474          */
 475         protected function doTable( $name ) {
 476                 global $wgSharedDB, $wgSharedTables;
 477
 478                 // Don't bother to check $wgSharedTables if there isn't a shared database
 479                 // or the user actually also wants to do updates on the shared database.
 480                 if ( $wgSharedDB === null || $this->shared ) {
 481                         return true;
 482                 }
 483
 484                 return !in_array( $name, $wgSharedTables );
 485         }
 486
 487         /**
 488          * Before 1.17, we used to handle updates via stuff like
 489          * $wgExtNewTables/Fields/Indexes. This is nasty :) We refactored a lot
 490          * of this in 1.17 but we want to remain back-compatible for a while. So
 491          * load up these old global-based things into our update list.
 492          *
 493          * @return array
 494          */
 495         protected function getOldGlobalUpdates() {
 496                 global $wgExtNewFields, $wgExtNewTables, $wgExtModifiedFields,
 497                         $wgExtNewIndexes;
 498
 499                 $updates = array();
 500
 501                 foreach ( $wgExtNewTables as $tableRecord ) {
 502                         $updates[] = array(
 503                                 'addTable', $tableRecord[0], $tableRecord[1], true
 504                         );
 505                 }
 506
 507                 foreach ( $wgExtNewFields as $fieldRecord ) {
 508                         $updates[] = array(
 509                                 'addField', $fieldRecord[0], $fieldRecord[1],
 510                                         $fieldRecord[2], true
 511                         );
 512                 }
 513
 514                 foreach ( $wgExtNewIndexes as $fieldRecord ) {
 515                         $updates[] = array(
 516                                 'addIndex', $fieldRecord[0], $fieldRecord[1],
 517                                         $fieldRecord[2], true
 518                         );
 519                 }
 520
 521                 foreach ( $wgExtModifiedFields as $fieldRecord ) {
 522                         $updates[] = array(
 523                                 'modifyField', $fieldRecord[0], $fieldRecord[1],
 524                                         $fieldRecord[2], true
 525                         );
 526                 }
 527
 528                 return $updates;
 529         }
 530
 531         /**
 532          * Get an array of updates to perform on the database. Should return a
 533          * multi-dimensional array. The main key is the MediaWiki version (1.12,
 534          * 1.13...) with the values being arrays of updates, identical to how
 535          * updaters.inc did it (for now)
 536          *
 537          * @return Array
 538          */
 539         protected abstract function getCoreUpdateList();
 540
 541         /**
 542          * Append an SQL fragment to the open file handle.
 543          *
 544          * @param $filename String: File name to open
 545          */
 546         public function copyFile( $filename ) {
 547                 $this->db->sourceFile( $filename, false, false, false,
 548                         array( $this, 'appendLine' )
 549                 );
 550         }
 551
 552         /**
 553          * Append a line to the open filehandle.  The line is assumed to
 554          * be a complete SQL statement.
 555          *
 556          * This is used as a callback for for sourceLine().
 557          *
 558          * @param $line String text to append to the file
 559          * @return Boolean false to skip actually executing the file
 560          * @throws MWException
 561          */
 562         public function appendLine( $line ) {
 563                 $line = rtrim( $line ) . ";\n";
 564                 if( fwrite( $this->fileHandle, $line ) === false ) {
 565                         throw new MWException( "trouble writing file" );
 566                 }
 567                 return false;
 568         }
 569
 570         /**
 571          * Applies a SQL patch
 572          * @param $path String Path to the patch file
 573          * @param $isFullPath Boolean Whether to treat $path as a relative or not
 574          * @param $msg String Description of the patch
 575          * @return boolean false if patch is skipped.
 576          */
 577         protected function applyPatch( $path, $isFullPath = false, $msg = null ) {
 578                 if ( $msg === null ) {
 579                         $msg = "Applying $path patch";
 580                 }
 581                 if ( $this->skipSchema ) {
 582                         $this->output( "...skipping schema change ($msg).\n" );
 583                         return false;
 584                 }
 585
 586                 $this->output( "$msg ..." );
 587
 588                 if ( !$isFullPath ) {
 589                         $path = $this->db->patchPath( $path );
 590                 }
 591                 if( $this->fileHandle !== null ) {
 592                         $this->copyFile( $path );
 593                 } else {
 594                         $this->db->sourceFile( $path );
 595                 }
 596                 $this->output( "done.\n" );
 597                 return true;
 598         }
 599
 600         /**
 601          * Add a new table to the database
 602          * @param $name String Name of the new table
 603          * @param $patch String Path to the patch file
 604          * @param $fullpath Boolean Whether to treat $patch path as a relative or not
 605          * @return Boolean false if this was skipped because schema changes are skipped
 606          */
 607         protected function addTable( $name, $patch, $fullpath = false ) {
 608                 if ( !$this->doTable( $name ) ) {
 609                         return true;
 610                 }
 611
 612                 if ( $this->db->tableExists( $name, __METHOD__ ) ) {
 613                         $this->output( "...$name table already exists.\n" );
 614                 } else {
 615                         return $this->applyPatch( $patch, $fullpath, "Creating $name table" );
 616                 }
 617                 return true;
 618         }
 619
 620         /**
 621          * Add a new field to an existing table
 622          * @param $table String Name of the table to modify
 623          * @param $field String Name of the new field
 624          * @param $patch String Path to the patch file
 625          * @param $fullpath Boolean Whether to treat $patch path as a relative or not
 626          * @return Boolean false if this was skipped because schema changes are skipped
 627          */
 628         protected function addField( $table, $field, $patch, $fullpath = false ) {
 629                 if ( !$this->doTable( $table ) ) {
 630                         return true;
 631                 }
 632
 633                 if ( !$this->db->tableExists( $table, __METHOD__ ) ) {
 634                         $this->output( "...$table table does not exist, skipping new field patch.\n" );
 635                 } elseif ( $this->db->fieldExists( $table, $field, __METHOD__ ) ) {
 636                         $this->output( "...have $field field in $table table.\n" );
 637                 } else {
 638                         return $this->applyPatch( $patch, $fullpath, "Adding $field field to table $table" );
 639                 }
 640                 return true;
 641         }
 642
 643         /**
 644          * Add a new index to an existing table
 645          * @param $table String Name of the table to modify
 646          * @param $index String Name of the new index
 647          * @param $patch String Path to the patch file
 648          * @param $fullpath Boolean Whether to treat $patch path as a relative or not
 649          * @return Boolean false if this was skipped because schema changes are skipped
 650          */
 651         protected function addIndex( $table, $index, $patch, $fullpath = false ) {
 652                 if ( !$this->doTable( $table ) ) {
 653                         return true;
 654                 }
 655
 656                 if ( !$this->db->tableExists( $table, __METHOD__ ) ) {
 657                         $this->output( "...skipping: '$table' table doesn't exist yet.\n" );
 658                         return false;
 659                 } else if ( $this->db->indexExists( $table, $index, __METHOD__ ) ) {
 660                         $this->output( "...index $index already set on $table table.\n" );
 661                 } else {
 662                         return $this->applyPatch( $patch, $fullpath, "Adding index $index to table $table" );
 663                 }
 664                 return true;
 665         }
 666
 667         /**
 668          * Drop a field from an existing table
 669          *
 670          * @param $table String Name of the table to modify
 671          * @param $field String Name of the old field
 672          * @param $patch String Path to the patch file
 673          * @param $fullpath Boolean Whether to treat $patch path as a relative or not
 674          * @return Boolean false if this was skipped because schema changes are skipped
 675          */
 676         protected function dropField( $table, $field, $patch, $fullpath = false ) {
 677                 if ( !$this->doTable( $table ) ) {
 678                         return true;
 679                 }
 680
 681                 if ( $this->db->fieldExists( $table, $field, __METHOD__ ) ) {
 682                         return $this->applyPatch( $patch, $fullpath, "Table $table contains $field field. Dropping" );
 683                 } else {
 684                         $this->output( "...$table table does not contain $field field.\n" );
 685                 }
 686                 return true;
 687         }
 688
 689         /**
 690          * Drop an index from an existing table
 691          *
 692          * @param $table String: Name of the table to modify
 693          * @param $index String: Name of the old index
 694          * @param $patch String: Path to the patch file
 695          * @param $fullpath Boolean: Whether to treat $patch path as a relative or not
 696          * @return Boolean false if this was skipped because schema changes are skipped
 697          */
 698         protected function dropIndex( $table, $index, $patch, $fullpath = false ) {
 699                 if ( !$this->doTable( $table ) ) {
 700                         return true;
 701                 }
 702
 703                 if ( $this->db->indexExists( $table, $index, __METHOD__ ) ) {
 704                         return $this->applyPatch( $patch, $fullpath, "Dropping $index index from table $table" );
 705                 } else {
 706                         $this->output( "...$index key doesn't exist.\n" );
 707                 }
 708                 return true;
 709         }
 710
 711         /**
 712          * If the specified table exists, drop it, or execute the
 713          * patch if one is provided.
 714          *
 715          * Public @since 1.20
 716          *
 717          * @param $table string
 718          * @param $patch string|false
 719          * @param $fullpath bool
 720          * @return Boolean false if this was skipped because schema changes are skipped
 721          */
 722         public function dropTable( $table, $patch = false, $fullpath = false ) {
 723                 if ( !$this->doTable( $table ) ) {
 724                         return true;
 725                 }
 726
 727                 if ( $this->db->tableExists( $table, __METHOD__ ) ) {
 728                         $msg = "Dropping table $table";
 729
 730                         if ( $patch === false ) {
 731                                 $this->output( "$msg ..." );
 732                                 $this->db->dropTable( $table, __METHOD__ );
 733                                 $this->output( "done.\n" );
 734                         }
 735                         else {
 736                                 return $this->applyPatch( $patch, $fullpath, $msg );
 737                         }
 738                 } else {
 739                         $this->output( "...$table doesn't exist.\n" );
 740                 }
 741                 return true;
 742         }
 743
 744         /**
 745          * Modify an existing field
 746          *
 747          * @param $table String: name of the table to which the field belongs
 748          * @param $field String: name of the field to modify
 749          * @param $patch String: path to the patch file
 750          * @param $fullpath Boolean: whether to treat $patch path as a relative or not
 751          * @return Boolean false if this was skipped because schema changes are skipped
 752          */
 753         public function modifyField( $table, $field, $patch, $fullpath = false ) {
 754                 if ( !$this->doTable( $table ) ) {
 755                         return true;
 756                 }
 757
 758                 $updateKey = "$table-$field-$patch";
 759                 if ( !$this->db->tableExists( $table, __METHOD__ ) ) {
 760                         $this->output( "...$table table does not exist, skipping modify field patch.\n" );
 761                 } elseif ( !$this->db->fieldExists( $table, $field, __METHOD__ ) ) {
 762                         $this->output( "...$field field does not exist in $table table, skipping modify field patch.\n" );
 763                 } elseif( $this->updateRowExists( $updateKey ) ) {
 764                         $this->output( "...$field in table $table already modified by patch $patch.\n" );
 765                 } else {
 766                         $this->insertUpdateRow( $updateKey );
 767                         return $this->applyPatch( $patch, $fullpath, "Modifying $field field of table $table" );
 768                 }
 769                 return true;
 770         }
 771
 772         /**
 773          * Purge the objectcache table
 774          */
 775         public function purgeCache() {
 776                 global $wgLocalisationCacheConf;
 777                 # We can't guarantee that the user will be able to use TRUNCATE,
 778                 # but we know that DELETE is available to us
 779                 $this->output( "Purging caches..." );
 780                 $this->db->delete( 'objectcache', '*', __METHOD__ );
 781                 if ( $wgLocalisationCacheConf['manualRecache'] ) {
 782                         $this->rebuildLocalisationCache();
 783                 }
 784                 $this->output( "done.\n" );
 785         }
 786
 787         /**
 788          * Check the site_stats table is not properly populated.
 789          */
 790         protected function checkStats() {
 791                 $this->output( "...site_stats is populated..." );
 792                 $row = $this->db->selectRow( 'site_stats', '*', array( 'ss_row_id' => 1 ), __METHOD__ );
 793                 if ( $row === false ) {
 794                         $this->output( "data is missing! rebuilding...\n" );
 795                 } elseif ( isset( $row->site_stats ) && $row->ss_total_pages == -1 ) {
 796                         $this->output( "missing ss_total_pages, rebuilding...\n" );
 797                 } else {
 798                         $this->output( "done.\n" );
 799                         return;
 800                 }
 801                 SiteStatsInit::doAllAndCommit( $this->db );
 802         }
 803
 804         # Common updater functions
 805
 806         /**
 807          * Sets the number of active users in the site_stats table
 808          */
 809         protected function doActiveUsersInit() {
 810                 $activeUsers = $this->db->selectField( 'site_stats', 'ss_active_users', false, __METHOD__ );
 811                 if ( $activeUsers == -1 ) {
 812                         $activeUsers = $this->db->selectField( 'recentchanges',
 813                                 'COUNT( DISTINCT rc_user_text )',
 814                                 array( 'rc_user != 0', 'rc_bot' => 0, "rc_log_type != 'newusers'" ), __METHOD__
 815                         );
 816                         $this->db->update( 'site_stats',
 817                                 array( 'ss_active_users' => intval( $activeUsers ) ),
 818                                 array( 'ss_row_id' => 1 ), __METHOD__, array( 'LIMIT' => 1 )
 819                         );
 820                 }
 821                 $this->output( "...ss_active_users user count set...\n" );
 822         }
 823
 824         /**
 825          * Populates the log_user_text field in the logging table
 826          */
 827         protected function doLogUsertextPopulation() {
 828                 if ( !$this->updateRowExists( 'populate log_usertext' ) ) {
 829                         $this->output(
 830                         "Populating log_user_text field, printing progress markers. For large\n" .
 831                         "databases, you may want to hit Ctrl-C and do this manually with\n" .
 832                         "maintenance/populateLogUsertext.php.\n" );
 833
 834                         $task = $this->maintenance->runChild( 'PopulateLogUsertext' );
 835                         $task->execute();
 836                         $this->output( "done.\n" );
 837                 }
 838         }
 839
 840         /**
 841          * Migrate log params to new table and index for searching
 842          */
 843         protected function doLogSearchPopulation() {
 844                 if ( !$this->updateRowExists( 'populate log_search' ) ) {
 845                         $this->output(
 846                                 "Populating log_search table, printing progress markers. For large\n" .
 847                                 "databases, you may want to hit Ctrl-C and do this manually with\n" .
 848                                 "maintenance/populateLogSearch.php.\n" );
 849
 850                         $task = $this->maintenance->runChild( 'PopulateLogSearch' );
 851                         $task->execute();
 852                         $this->output( "done.\n" );
 853                 }
 854         }
 855
 856         /**
 857          * Updates the timestamps in the transcache table
 858          */
 859         protected function doUpdateTranscacheField() {
 860                 if ( $this->updateRowExists( 'convert transcache field' ) ) {
 861                         $this->output( "...transcache tc_time already converted.\n" );
 862                         return true;
 863                 }
 864
 865                 return $this->applyPatch( 'patch-tc-timestamp.sql', false,
 866                         "Converting tc_time from UNIX epoch to MediaWiki timestamp" );
 867         }
 868
 869         /**
 870          * Update CategoryLinks collation
 871          */
 872         protected function doCollationUpdate() {
 873                 global $wgCategoryCollation;
 874                 if ( $this->db->fieldExists( 'categorylinks', 'cl_collation', __METHOD__ ) ) {
 875                         if ( $this->db->selectField(
 876                                 'categorylinks',
 877                                 'COUNT(*)',
 878                                 'cl_collation != ' . $this->db->addQuotes( $wgCategoryCollation ),
 879                                 __METHOD__
 880                                 ) == 0 ) {
 881                                         $this->output( "...collations up-to-date.\n" );
 882                                         return;
 883                         }
 884
 885                         $this->output( "Updating category collations..." );
 886                         $task = $this->maintenance->runChild( 'UpdateCollation' );
 887                         $task->execute();
 888                         $this->output( "...done.\n" );
 889                 }
 890         }
 891
 892         /**
 893          * Migrates user options from the user table blob to user_properties
 894          */
 895         protected function doMigrateUserOptions() {
 896                 if( $this->db->tableExists( 'user_properties' ) ) {
 897                         $cl = $this->maintenance->runChild( 'ConvertUserOptions', 'convertUserOptions.php' );
 898                         $cl->execute();
 899                         $this->output( "done.\n" );
 900                 }
 901         }
 902
 903         /**
 904          * Rebuilds the localisation cache
 905          */
 906         protected function rebuildLocalisationCache() {
 907                 /**
 908                  * @var $cl RebuildLocalisationCache
 909                  */
 910                 $cl = $this->maintenance->runChild( 'RebuildLocalisationCache', 'rebuildLocalisationCache.php' );
 911                 $this->output( "Rebuilding localisation cache...\n" );
 912                 $cl->setForce();
 913                 $cl->execute();
 914                 $this->output( "done.\n" );
 915         }
 916 }