includes/installer/PostgresInstaller.php

   1 <?php
   2 /**
   3  * PostgreSQL-specific installer.
   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 use Wikimedia\Rdbms\Database;
  25 use Wikimedia\Rdbms\DBQueryError;
  26 use Wikimedia\Rdbms\DBConnectionError;
  27
  28 /**
  29  * Class for setting up the MediaWiki database using Postgres.
  30  *
  31  * @ingroup Deployment
  32  * @since 1.17
  33  */
  34 class PostgresInstaller extends DatabaseInstaller {
  35
  36         protected $globalNames = [
  37                 'wgDBserver',
  38                 'wgDBport',
  39                 'wgDBname',
  40                 'wgDBuser',
  41                 'wgDBpassword',
  42                 'wgDBmwschema',
  43         ];
  44
  45         protected $internalDefaults = [
  46                 '_InstallUser' => 'postgres',
  47         ];
  48
  49         public static $minimumVersion = '9.2';
  50         protected static $notMinimumVersionMessage = 'config-postgres-old';
  51         public $maxRoleSearchDepth = 5;
  52
  53         protected $pgConns = [];
  54
  55         function getName() {
  56                 return 'postgres';
  57         }
  58
  59         public function isCompiled() {
  60                 return self::checkExtension( 'pgsql' );
  61         }
  62
  63         function getConnectForm() {
  64                 return $this->getTextBox(
  65                         'wgDBserver',
  66                         'config-db-host',
  67                         [],
  68                         $this->parent->getHelpBox( 'config-db-host-help' )
  69                 ) .
  70                         $this->getTextBox( 'wgDBport', 'config-db-port' ) .
  71                         Html::openElement( 'fieldset' ) .
  72                         Html::element( 'legend', [], wfMessage( 'config-db-wiki-settings' )->text() ) .
  73                         $this->getTextBox(
  74                                 'wgDBname',
  75                                 'config-db-name',
  76                                 [],
  77                                 $this->parent->getHelpBox( 'config-db-name-help' )
  78                         ) .
  79                         $this->getTextBox(
  80                                 'wgDBmwschema',
  81                                 'config-db-schema',
  82                                 [],
  83                                 $this->parent->getHelpBox( 'config-db-schema-help' )
  84                         ) .
  85                         Html::closeElement( 'fieldset' ) .
  86                         $this->getInstallUserBox();
  87         }
  88
  89         function submitConnectForm() {
  90                 // Get variables from the request
  91                 $newValues = $this->setVarsFromRequest( [
  92                         'wgDBserver',
  93                         'wgDBport',
  94                         'wgDBname',
  95                         'wgDBmwschema'
  96                 ] );
  97
  98                 // Validate them
  99                 $status = Status::newGood();
 100                 if ( !strlen( $newValues['wgDBname'] ) ) {
 101                         $status->fatal( 'config-missing-db-name' );
 102                 } elseif ( !preg_match( '/^[a-zA-Z0-9_]+$/', $newValues['wgDBname'] ) ) {
 103                         $status->fatal( 'config-invalid-db-name', $newValues['wgDBname'] );
 104                 }
 105                 if ( !preg_match( '/^[a-zA-Z0-9_]*$/', $newValues['wgDBmwschema'] ) ) {
 106                         $status->fatal( 'config-invalid-schema', $newValues['wgDBmwschema'] );
 107                 }
 108
 109                 // Submit user box
 110                 if ( $status->isOK() ) {
 111                         $status->merge( $this->submitInstallUserBox() );
 112                 }
 113                 if ( !$status->isOK() ) {
 114                         return $status;
 115                 }
 116
 117                 $status = $this->getPgConnection( 'create-db' );
 118                 if ( !$status->isOK() ) {
 119                         return $status;
 120                 }
 121                 /**
 122                  * @var Database $conn
 123                  */
 124                 $conn = $status->value;
 125
 126                 // Check version
 127                 $version = $conn->getServerVersion();
 128                 $status = static::meetsMinimumRequirement( $version );
 129                 if ( !$status->isOK() ) {
 130                         return $status;
 131                 }
 132
 133                 $this->setVar( 'wgDBuser', $this->getVar( '_InstallUser' ) );
 134                 $this->setVar( 'wgDBpassword', $this->getVar( '_InstallPassword' ) );
 135
 136                 return Status::newGood();
 137         }
 138
 139         public function getConnection() {
 140                 $status = $this->getPgConnection( 'create-tables' );
 141                 if ( $status->isOK() ) {
 142                         $this->db = $status->value;
 143                 }
 144
 145                 return $status;
 146         }
 147
 148         public function openConnection() {
 149                 return $this->openPgConnection( 'create-tables' );
 150         }
 151
 152         /**
 153          * Open a PG connection with given parameters
 154          * @param string $user User name
 155          * @param string $password
 156          * @param string $dbName Database name
 157          * @param string $schema Database schema
 158          * @return Status
 159          */
 160         protected function openConnectionWithParams( $user, $password, $dbName, $schema ) {
 161                 $status = Status::newGood();
 162                 try {
 163                         $db = Database::factory( 'postgres', [
 164                                 'host' => $this->getVar( 'wgDBserver' ),
 165                                 'port' => $this->getVar( 'wgDBport' ),
 166                                 'user' => $user,
 167                                 'password' => $password,
 168                                 'dbname' => $dbName,
 169                                 'schema' => $schema,
 170                                 'keywordTableMap' => [ 'user' => 'mwuser', 'text' => 'pagecontent' ],
 171                         ] );
 172                         $status->value = $db;
 173                 } catch ( DBConnectionError $e ) {
 174                         $status->fatal( 'config-connection-error', $e->getMessage() );
 175                 }
 176
 177                 return $status;
 178         }
 179
 180         /**
 181          * Get a special type of connection
 182          * @param string $type See openPgConnection() for details.
 183          * @return Status
 184          */
 185         protected function getPgConnection( $type ) {
 186                 if ( isset( $this->pgConns[$type] ) ) {
 187                         return Status::newGood( $this->pgConns[$type] );
 188                 }
 189                 $status = $this->openPgConnection( $type );
 190
 191                 if ( $status->isOK() ) {
 192                         /**
 193                          * @var Database $conn
 194                          */
 195                         $conn = $status->value;
 196                         $conn->clearFlag( DBO_TRX );
 197                         $conn->commit( __METHOD__ );
 198                         $this->pgConns[$type] = $conn;
 199                 }
 200
 201                 return $status;
 202         }
 203
 204         /**
 205          * Get a connection of a specific PostgreSQL-specific type. Connections
 206          * of a given type are cached.
 207          *
 208          * PostgreSQL lacks cross-database operations, so after the new database is
 209          * created, you need to make a separate connection to connect to that
 210          * database and add tables to it.
 211          *
 212          * New tables are owned by the user that creates them, and MediaWiki's
 213          * PostgreSQL support has always assumed that the table owner will be
 214          * $wgDBuser. So before we create new tables, we either need to either
 215          * connect as the other user or to execute a SET ROLE command. Using a
 216          * separate connection for this allows us to avoid accidental cross-module
 217          * dependencies.
 218          *
 219          * @param string $type The type of connection to get:
 220          *    - create-db:     A connection for creating DBs, suitable for pre-
 221          *                     installation.
 222          *    - create-schema: A connection to the new DB, for creating schemas and
 223          *                     other similar objects in the new DB.
 224          *    - create-tables: A connection with a role suitable for creating tables.
 225          *
 226          * @throws MWException
 227          * @return Status On success, a connection object will be in the value member.
 228          */
 229         protected function openPgConnection( $type ) {
 230                 switch ( $type ) {
 231                         case 'create-db':
 232                                 return $this->openConnectionToAnyDB(
 233                                         $this->getVar( '_InstallUser' ),
 234                                         $this->getVar( '_InstallPassword' ) );
 235                         case 'create-schema':
 236                                 return $this->openConnectionWithParams(
 237                                         $this->getVar( '_InstallUser' ),
 238                                         $this->getVar( '_InstallPassword' ),
 239                                         $this->getVar( 'wgDBname' ),
 240                                         $this->getVar( 'wgDBmwschema' ) );
 241                         case 'create-tables':
 242                                 $status = $this->openPgConnection( 'create-schema' );
 243                                 if ( $status->isOK() ) {
 244                                         /**
 245                                          * @var Database $conn
 246                                          */
 247                                         $conn = $status->value;
 248                                         $safeRole = $conn->addIdentifierQuotes( $this->getVar( 'wgDBuser' ) );
 249                                         $conn->query( "SET ROLE $safeRole" );
 250                                 }
 251
 252                                 return $status;
 253                         default:
 254                                 throw new MWException( "Invalid special connection type: \"$type\"" );
 255                 }
 256         }
 257
 258         public function openConnectionToAnyDB( $user, $password ) {
 259                 $dbs = [
 260                         'template1',
 261                         'postgres',
 262                 ];
 263                 if ( !in_array( $this->getVar( 'wgDBname' ), $dbs ) ) {
 264                         array_unshift( $dbs, $this->getVar( 'wgDBname' ) );
 265                 }
 266                 $conn = false;
 267                 $status = Status::newGood();
 268                 foreach ( $dbs as $db ) {
 269                         try {
 270                                 $p = [
 271                                         'host' => $this->getVar( 'wgDBserver' ),
 272                                         'user' => $user,
 273                                         'password' => $password,
 274                                         'dbname' => $db
 275                                 ];
 276                                 $conn = Database::factory( 'postgres', $p );
 277                         } catch ( DBConnectionError $error ) {
 278                                 $conn = false;
 279                                 $status->fatal( 'config-pg-test-error', $db,
 280                                         $error->getMessage() );
 281                         }
 282                         if ( $conn !== false ) {
 283                                 break;
 284                         }
 285                 }
 286                 if ( $conn !== false ) {
 287                         return Status::newGood( $conn );
 288                 } else {
 289                         return $status;
 290                 }
 291         }
 292
 293         protected function getInstallUserPermissions() {
 294                 $status = $this->getPgConnection( 'create-db' );
 295                 if ( !$status->isOK() ) {
 296                         return false;
 297                 }
 298                 /**
 299                  * @var Database $conn
 300                  */
 301                 $conn = $status->value;
 302                 $superuser = $this->getVar( '_InstallUser' );
 303
 304                 $row = $conn->selectRow( '"pg_catalog"."pg_roles"', '*',
 305                         [ 'rolname' => $superuser ], __METHOD__ );
 306
 307                 return $row;
 308         }
 309
 310         protected function canCreateAccounts() {
 311                 $perms = $this->getInstallUserPermissions();
 312                 if ( !$perms ) {
 313                         return false;
 314                 }
 315
 316                 return $perms->rolsuper === 't' || $perms->rolcreaterole === 't';
 317         }
 318
 319         protected function isSuperUser() {
 320                 $perms = $this->getInstallUserPermissions();
 321                 if ( !$perms ) {
 322                         return false;
 323                 }
 324
 325                 return $perms->rolsuper === 't';
 326         }
 327
 328         public function getSettingsForm() {
 329                 if ( $this->canCreateAccounts() ) {
 330                         $noCreateMsg = false;
 331                 } else {
 332                         $noCreateMsg = 'config-db-web-no-create-privs';
 333                 }
 334                 $s = $this->getWebUserBox( $noCreateMsg );
 335
 336                 return $s;
 337         }
 338
 339         public function submitSettingsForm() {
 340                 $status = $this->submitWebUserBox();
 341                 if ( !$status->isOK() ) {
 342                         return $status;
 343                 }
 344
 345                 $same = $this->getVar( 'wgDBuser' ) === $this->getVar( '_InstallUser' );
 346
 347                 if ( $same ) {
 348                         $exists = true;
 349                 } else {
 350                         // Check if the web user exists
 351                         // Connect to the database with the install user
 352                         $status = $this->getPgConnection( 'create-db' );
 353                         if ( !$status->isOK() ) {
 354                                 return $status;
 355                         }
 356                         // @phan-suppress-next-line PhanUndeclaredMethod
 357                         $exists = $status->value->roleExists( $this->getVar( 'wgDBuser' ) );
 358                 }
 359
 360                 // Validate the create checkbox
 361                 if ( $this->canCreateAccounts() && !$same && !$exists ) {
 362                         $create = $this->getVar( '_CreateDBAccount' );
 363                 } else {
 364                         $this->setVar( '_CreateDBAccount', false );
 365                         $create = false;
 366                 }
 367
 368                 if ( !$create && !$exists ) {
 369                         if ( $this->canCreateAccounts() ) {
 370                                 $msg = 'config-install-user-missing-create';
 371                         } else {
 372                                 $msg = 'config-install-user-missing';
 373                         }
 374
 375                         return Status::newFatal( $msg, $this->getVar( 'wgDBuser' ) );
 376                 }
 377
 378                 if ( !$exists ) {
 379                         // No more checks to do
 380                         return Status::newGood();
 381                 }
 382
 383                 // Existing web account. Test the connection.
 384                 $status = $this->openConnectionToAnyDB(
 385                         $this->getVar( 'wgDBuser' ),
 386                         $this->getVar( 'wgDBpassword' ) );
 387                 if ( !$status->isOK() ) {
 388                         return $status;
 389                 }
 390
 391                 // The web user is conventionally the table owner in PostgreSQL
 392                 // installations. Make sure the install user is able to create
 393                 // objects on behalf of the web user.
 394                 if ( $same || $this->canCreateObjectsForWebUser() ) {
 395                         return Status::newGood();
 396                 } else {
 397                         return Status::newFatal( 'config-pg-not-in-role' );
 398                 }
 399         }
 400
 401         /**
 402          * Returns true if the install user is able to create objects owned
 403          * by the web user, false otherwise.
 404          * @return bool
 405          */
 406         protected function canCreateObjectsForWebUser() {
 407                 if ( $this->isSuperUser() ) {
 408                         return true;
 409                 }
 410
 411                 $status = $this->getPgConnection( 'create-db' );
 412                 if ( !$status->isOK() ) {
 413                         return false;
 414                 }
 415                 $conn = $status->value;
 416                 $installerId = $conn->selectField( '"pg_catalog"."pg_roles"', 'oid',
 417                         [ 'rolname' => $this->getVar( '_InstallUser' ) ], __METHOD__ );
 418                 $webId = $conn->selectField( '"pg_catalog"."pg_roles"', 'oid',
 419                         [ 'rolname' => $this->getVar( 'wgDBuser' ) ], __METHOD__ );
 420
 421                 return $this->isRoleMember( $conn, $installerId, $webId, $this->maxRoleSearchDepth );
 422         }
 423
 424         /**
 425          * Recursive helper for canCreateObjectsForWebUser().
 426          * @param Database $conn
 427          * @param int $targetMember Role ID of the member to look for
 428          * @param int $group Role ID of the group to look for
 429          * @param int $maxDepth Maximum recursive search depth
 430          * @return bool
 431          */
 432         protected function isRoleMember( $conn, $targetMember, $group, $maxDepth ) {
 433                 if ( $targetMember === $group ) {
 434                         // A role is always a member of itself
 435                         return true;
 436                 }
 437                 // Get all members of the given group
 438                 $res = $conn->select( '"pg_catalog"."pg_auth_members"', [ 'member' ],
 439                         [ 'roleid' => $group ], __METHOD__ );
 440                 foreach ( $res as $row ) {
 441                         if ( $row->member == $targetMember ) {
 442                                 // Found target member
 443                                 return true;
 444                         }
 445                         // Recursively search each member of the group to see if the target
 446                         // is a member of it, up to the given maximum depth.
 447                         if ( $maxDepth > 0 &&
 448                                 $this->isRoleMember( $conn, $targetMember, $row->member, $maxDepth - 1 )
 449                         ) {
 450                                 // Found member of member
 451                                 return true;
 452                         }
 453                 }
 454
 455                 return false;
 456         }
 457
 458         public function preInstall() {
 459                 $createDbAccount = [
 460                         'name' => 'user',
 461                         'callback' => [ $this, 'setupUser' ],
 462                 ];
 463                 $commitCB = [
 464                         'name' => 'pg-commit',
 465                         'callback' => [ $this, 'commitChanges' ],
 466                 ];
 467                 $plpgCB = [
 468                         'name' => 'pg-plpgsql',
 469                         'callback' => [ $this, 'setupPLpgSQL' ],
 470                 ];
 471                 $schemaCB = [
 472                         'name' => 'schema',
 473                         'callback' => [ $this, 'setupSchema' ]
 474                 ];
 475
 476                 if ( $this->getVar( '_CreateDBAccount' ) ) {
 477                         $this->parent->addInstallStep( $createDbAccount, 'database' );
 478                 }
 479                 $this->parent->addInstallStep( $commitCB, 'interwiki' );
 480                 $this->parent->addInstallStep( $plpgCB, 'database' );
 481                 $this->parent->addInstallStep( $schemaCB, 'database' );
 482         }
 483
 484         function setupDatabase() {
 485                 $status = $this->getPgConnection( 'create-db' );
 486                 if ( !$status->isOK() ) {
 487                         return $status;
 488                 }
 489                 $conn = $status->value;
 490
 491                 $dbName = $this->getVar( 'wgDBname' );
 492
 493                 $exists = $conn->selectField( '"pg_catalog"."pg_database"', '1',
 494                         [ 'datname' => $dbName ], __METHOD__ );
 495                 if ( !$exists ) {
 496                         $safedb = $conn->addIdentifierQuotes( $dbName );
 497                         $conn->query( "CREATE DATABASE $safedb", __METHOD__ );
 498                 }
 499
 500                 return Status::newGood();
 501         }
 502
 503         function setupSchema() {
 504                 // Get a connection to the target database
 505                 $status = $this->getPgConnection( 'create-schema' );
 506                 if ( !$status->isOK() ) {
 507                         return $status;
 508                 }
 509                 /** @var DatabasePostgres $conn */
 510                 $conn = $status->value;
 511                 '@phan-var DatabasePostgres $conn';
 512
 513                 // Create the schema if necessary
 514                 $schema = $this->getVar( 'wgDBmwschema' );
 515                 $safeschema = $conn->addIdentifierQuotes( $schema );
 516                 $safeuser = $conn->addIdentifierQuotes( $this->getVar( 'wgDBuser' ) );
 517                 if ( !$conn->schemaExists( $schema ) ) {
 518                         try {
 519                                 $conn->query( "CREATE SCHEMA $safeschema AUTHORIZATION $safeuser" );
 520                         } catch ( DBQueryError $e ) {
 521                                 return Status::newFatal( 'config-install-pg-schema-failed',
 522                                         $this->getVar( '_InstallUser' ), $schema );
 523                         }
 524                 }
 525
 526                 // Select the new schema in the current connection
 527                 $conn->determineCoreSchema( $schema );
 528
 529                 return Status::newGood();
 530         }
 531
 532         function commitChanges() {
 533                 $this->db->commit( __METHOD__ );
 534
 535                 return Status::newGood();
 536         }
 537
 538         function setupUser() {
 539                 if ( !$this->getVar( '_CreateDBAccount' ) ) {
 540                         return Status::newGood();
 541                 }
 542
 543                 $status = $this->getPgConnection( 'create-db' );
 544                 if ( !$status->isOK() ) {
 545                         return $status;
 546                 }
 547                 /** @var DatabasePostgres $conn */
 548                 $conn = $status->value;
 549                 '@phan-var DatabasePostgres $conn';
 550
 551                 $safeuser = $conn->addIdentifierQuotes( $this->getVar( 'wgDBuser' ) );
 552                 $safepass = $conn->addQuotes( $this->getVar( 'wgDBpassword' ) );
 553
 554                 // Check if the user already exists
 555                 $userExists = $conn->roleExists( $this->getVar( 'wgDBuser' ) );
 556                 if ( !$userExists ) {
 557                         // Create the user
 558                         try {
 559                                 $sql = "CREATE ROLE $safeuser NOCREATEDB LOGIN PASSWORD $safepass";
 560
 561                                 // If the install user is not a superuser, we need to make the install
 562                                 // user a member of the new user's group, so that the install user will
 563                                 // be able to create a schema and other objects on behalf of the new user.
 564                                 if ( !$this->isSuperUser() ) {
 565                                         $sql .= ' ROLE' . $conn->addIdentifierQuotes( $this->getVar( '_InstallUser' ) );
 566                                 }
 567
 568                                 $conn->query( $sql, __METHOD__ );
 569                         } catch ( DBQueryError $e ) {
 570                                 return Status::newFatal( 'config-install-user-create-failed',
 571                                         $this->getVar( 'wgDBuser' ), $e->getMessage() );
 572                         }
 573                 }
 574
 575                 return Status::newGood();
 576         }
 577
 578         function getLocalSettings() {
 579                 $port = $this->getVar( 'wgDBport' );
 580                 $schema = $this->getVar( 'wgDBmwschema' );
 581
 582                 return "# Postgres specific settings
 583 \$wgDBport = \"{$port}\";
 584 \$wgDBmwschema = \"{$schema}\";";
 585         }
 586
 587         public function preUpgrade() {
 588                 global $wgDBuser, $wgDBpassword;
 589
 590                 # Normal user and password are selected after this step, so for now
 591                 # just copy these two
 592                 $wgDBuser = $this->getVar( '_InstallUser' );
 593                 $wgDBpassword = $this->getVar( '_InstallPassword' );
 594         }
 595
 596         public function createTables() {
 597                 $schema = $this->getVar( 'wgDBmwschema' );
 598
 599                 $status = $this->getConnection();
 600                 if ( !$status->isOK() ) {
 601                         return $status;
 602                 }
 603
 604                 /** @var DatabasePostgres $conn */
 605                 $conn = $status->value;
 606                 '@phan-var DatabasePostgres $conn';
 607
 608                 if ( $conn->tableExists( 'archive' ) ) {
 609                         $status->warning( 'config-install-tables-exist' );
 610                         $this->enableLB();
 611
 612                         return $status;
 613                 }
 614
 615                 $conn->begin( __METHOD__ );
 616
 617                 if ( !$conn->schemaExists( $schema ) ) {
 618                         $status->fatal( 'config-install-pg-schema-not-exist' );
 619
 620                         return $status;
 621                 }
 622                 $error = $conn->sourceFile( $this->getSchemaPath( $conn ) );
 623                 if ( $error !== true ) {
 624                         $conn->reportQueryError( $error, 0, '', __METHOD__ );
 625                         $conn->rollback( __METHOD__ );
 626                         $status->fatal( 'config-install-tables-failed', $error );
 627                 } else {
 628                         $conn->commit( __METHOD__ );
 629                 }
 630                 // Resume normal operations
 631                 if ( $status->isOK() ) {
 632                         $this->enableLB();
 633                 }
 634
 635                 return $status;
 636         }
 637
 638         public function getGlobalDefaults() {
 639                 // The default $wgDBmwschema is null, which breaks Postgres and other DBMSes that require
 640                 // the use of a schema, so we need to set it here
 641                 return array_merge( parent::getGlobalDefaults(), [
 642                         'wgDBmwschema' => 'mediawiki',
 643                 ] );
 644         }
 645
 646         public function setupPLpgSQL() {
 647                 // Connect as the install user, since it owns the database and so is
 648                 // the user that needs to run "CREATE LANGUAGE"
 649                 $status = $this->getPgConnection( 'create-schema' );
 650                 if ( !$status->isOK() ) {
 651                         return $status;
 652                 }
 653                 /**
 654                  * @var Database $conn
 655                  */
 656                 $conn = $status->value;
 657
 658                 $exists = $conn->selectField( '"pg_catalog"."pg_language"', 1,
 659                         [ 'lanname' => 'plpgsql' ], __METHOD__ );
 660                 if ( $exists ) {
 661                         // Already exists, nothing to do
 662                         return Status::newGood();
 663                 }
 664
 665                 // plpgsql is not installed, but if we have a pg_pltemplate table, we
 666                 // should be able to create it
 667                 $exists = $conn->selectField(
 668                         [ '"pg_catalog"."pg_class"', '"pg_catalog"."pg_namespace"' ],
 669                         1,
 670                         [
 671                                 'pg_namespace.oid=relnamespace',
 672                                 'nspname' => 'pg_catalog',
 673                                 'relname' => 'pg_pltemplate',
 674                         ],
 675                         __METHOD__ );
 676                 if ( $exists ) {
 677                         try {
 678                                 $conn->query( 'CREATE LANGUAGE plpgsql' );
 679                         } catch ( DBQueryError $e ) {
 680                                 return Status::newFatal( 'config-pg-no-plpgsql', $this->getVar( 'wgDBname' ) );
 681                         }
 682                 } else {
 683                         return Status::newFatal( 'config-pg-no-plpgsql', $this->getVar( 'wgDBname' ) );
 684                 }
 685
 686                 return Status::newGood();
 687         }
 688 }