includes/libs/rdbms/database/DBConnRef.php

   1 <?php
   2
   3 namespace Wikimedia\Rdbms;
   4
   5 use InvalidArgumentException;
   6
   7 /**
   8  * Helper class to handle automatically marking connections as reusable (via RAII pattern)
   9  * as well handling deferring the actual network connection until the handle is used
  10  *
  11  * @note: proxy methods are defined explicitly to avoid interface errors
  12  * @ingroup Database
  13  * @since 1.22
  14  */
  15 class DBConnRef implements IDatabase {
  16         /** @var ILoadBalancer */
  17         private $lb;
  18         /** @var Database|null Live connection handle */
  19         private $conn;
  20         /** @var array|null N-tuple of (server index, group, DatabaseDomain|string) */
  21         private $params;
  22
  23         const FLD_INDEX = 0;
  24         const FLD_GROUP = 1;
  25         const FLD_DOMAIN = 2;
  26         const FLD_FLAGS = 3;
  27
  28         /**
  29          * @param ILoadBalancer $lb Connection manager for $conn
  30          * @param Database|array $conn Database handle or (server index, query groups, domain, flags)
  31          */
  32         public function __construct( ILoadBalancer $lb, $conn ) {
  33                 $this->lb = $lb;
  34                 if ( $conn instanceof Database ) {
  35                         $this->conn = $conn; // live handle
  36                 } elseif ( is_array( $conn ) && count( $conn ) >= 4 && $conn[self::FLD_DOMAIN] !== false ) {
  37                         $this->params = $conn;
  38                 } else {
  39                         throw new InvalidArgumentException( "Missing lazy connection arguments." );
  40                 }
  41         }
  42
  43         function __call( $name, array $arguments ) {
  44                 if ( $this->conn === null ) {
  45                         list( $db, $groups, $wiki, $flags ) = $this->params;
  46                         $this->conn = $this->lb->getConnection( $db, $groups, $wiki, $flags );
  47                 }
  48
  49                 return $this->conn->$name( ...$arguments );
  50         }
  51
  52         public function getServerInfo() {
  53                 return $this->__call( __FUNCTION__, func_get_args() );
  54         }
  55
  56         public function bufferResults( $buffer = null ) {
  57                 return $this->__call( __FUNCTION__, func_get_args() );
  58         }
  59
  60         public function trxLevel() {
  61                 return $this->__call( __FUNCTION__, func_get_args() );
  62         }
  63
  64         public function trxTimestamp() {
  65                 return $this->__call( __FUNCTION__, func_get_args() );
  66         }
  67
  68         public function explicitTrxActive() {
  69                 return $this->__call( __FUNCTION__, func_get_args() );
  70         }
  71
  72         public function assertNoOpenTransactions() {
  73                 return $this->__call( __FUNCTION__, func_get_args() );
  74         }
  75
  76         public function tablePrefix( $prefix = null ) {
  77                 if ( $this->conn === null && $prefix === null ) {
  78                         $domain = DatabaseDomain::newFromId( $this->params[self::FLD_DOMAIN] );
  79                         // Avoid triggering a database connection
  80                         return $domain->getTablePrefix();
  81                 } elseif ( $this->conn !== null && $prefix === null ) {
  82                         // This will just return the prefix
  83                         return $this->__call( __FUNCTION__, func_get_args() );
  84                 }
  85                 // Disallow things that might confuse the LoadBalancer tracking
  86                 throw new DBUnexpectedError( $this, "Database selection is disallowed to enable reuse." );
  87         }
  88
  89         public function dbSchema( $schema = null ) {
  90                 if ( $this->conn === null && $schema === null ) {
  91                         $domain = DatabaseDomain::newFromId( $this->params[self::FLD_DOMAIN] );
  92                         // Avoid triggering a database connection
  93                         return $domain->getSchema();
  94                 } elseif ( $this->conn !== null && $schema === null ) {
  95                         // This will just return the schema
  96                         return $this->__call( __FUNCTION__, func_get_args() );
  97                 }
  98                 // Disallow things that might confuse the LoadBalancer tracking
  99                 throw new DBUnexpectedError( $this, "Database selection is disallowed to enable reuse." );
 100         }
 101
 102         public function getLBInfo( $name = null ) {
 103                 return $this->__call( __FUNCTION__, func_get_args() );
 104         }
 105
 106         public function setLBInfo( $name, $value = null ) {
 107                 // Disallow things that might confuse the LoadBalancer tracking
 108                 throw new DBUnexpectedError( $this, "Changing LB info is disallowed to enable reuse." );
 109         }
 110
 111         public function setLazyMasterHandle( IDatabase $conn ) {
 112                 // Disallow things that might confuse the LoadBalancer tracking
 113                 throw new DBUnexpectedError( $this, "Database injection is disallowed to enable reuse." );
 114         }
 115
 116         public function implicitGroupby() {
 117                 return $this->__call( __FUNCTION__, func_get_args() );
 118         }
 119
 120         public function implicitOrderby() {
 121                 return $this->__call( __FUNCTION__, func_get_args() );
 122         }
 123
 124         public function lastQuery() {
 125                 return $this->__call( __FUNCTION__, func_get_args() );
 126         }
 127
 128         public function doneWrites() {
 129                 return $this->__call( __FUNCTION__, func_get_args() );
 130         }
 131
 132         public function lastDoneWrites() {
 133                 return $this->__call( __FUNCTION__, func_get_args() );
 134         }
 135
 136         public function writesPending() {
 137                 return $this->__call( __FUNCTION__, func_get_args() );
 138         }
 139
 140         public function preCommitCallbacksPending() {
 141                 return $this->__call( __FUNCTION__, func_get_args() );
 142         }
 143
 144         public function writesOrCallbacksPending() {
 145                 return $this->__call( __FUNCTION__, func_get_args() );
 146         }
 147
 148         public function pendingWriteQueryDuration( $type = self::ESTIMATE_TOTAL ) {
 149                 return $this->__call( __FUNCTION__, func_get_args() );
 150         }
 151
 152         public function pendingWriteCallers() {
 153                 return $this->__call( __FUNCTION__, func_get_args() );
 154         }
 155
 156         public function pendingWriteRowsAffected() {
 157                 return $this->__call( __FUNCTION__, func_get_args() );
 158         }
 159
 160         public function isOpen() {
 161                 return $this->__call( __FUNCTION__, func_get_args() );
 162         }
 163
 164         public function setFlag( $flag, $remember = self::REMEMBER_NOTHING ) {
 165                 return $this->__call( __FUNCTION__, func_get_args() );
 166         }
 167
 168         public function clearFlag( $flag, $remember = self::REMEMBER_NOTHING ) {
 169                 return $this->__call( __FUNCTION__, func_get_args() );
 170         }
 171
 172         public function restoreFlags( $state = self::RESTORE_PRIOR ) {
 173                 return $this->__call( __FUNCTION__, func_get_args() );
 174         }
 175
 176         public function getFlag( $flag ) {
 177                 return $this->__call( __FUNCTION__, func_get_args() );
 178         }
 179
 180         public function getProperty( $name ) {
 181                 return $this->__call( __FUNCTION__, func_get_args() );
 182         }
 183
 184         public function getDomainID() {
 185                 if ( $this->conn === null ) {
 186                         $domain = $this->params[self::FLD_DOMAIN];
 187                         // Avoid triggering a database connection
 188                         return $domain instanceof DatabaseDomain ? $domain->getId() : $domain;
 189                 }
 190
 191                 return $this->__call( __FUNCTION__, func_get_args() );
 192         }
 193
 194         /**
 195          * @codeCoverageIgnore
 196          */
 197         public function getWikiID() {
 198                 return $this->getDomainID();
 199         }
 200
 201         public function getType() {
 202                 return $this->__call( __FUNCTION__, func_get_args() );
 203         }
 204
 205         public function fetchObject( $res ) {
 206                 return $this->__call( __FUNCTION__, func_get_args() );
 207         }
 208
 209         public function fetchRow( $res ) {
 210                 return $this->__call( __FUNCTION__, func_get_args() );
 211         }
 212
 213         public function numRows( $res ) {
 214                 return $this->__call( __FUNCTION__, func_get_args() );
 215         }
 216
 217         public function numFields( $res ) {
 218                 return $this->__call( __FUNCTION__, func_get_args() );
 219         }
 220
 221         public function fieldName( $res, $n ) {
 222                 return $this->__call( __FUNCTION__, func_get_args() );
 223         }
 224
 225         public function insertId() {
 226                 return $this->__call( __FUNCTION__, func_get_args() );
 227         }
 228
 229         public function dataSeek( $res, $row ) {
 230                 return $this->__call( __FUNCTION__, func_get_args() );
 231         }
 232
 233         public function lastErrno() {
 234                 return $this->__call( __FUNCTION__, func_get_args() );
 235         }
 236
 237         public function lastError() {
 238                 return $this->__call( __FUNCTION__, func_get_args() );
 239         }
 240
 241         public function affectedRows() {
 242                 return $this->__call( __FUNCTION__, func_get_args() );
 243         }
 244
 245         public function getSoftwareLink() {
 246                 return $this->__call( __FUNCTION__, func_get_args() );
 247         }
 248
 249         public function getServerVersion() {
 250                 return $this->__call( __FUNCTION__, func_get_args() );
 251         }
 252
 253         public function close() {
 254                 throw new DBUnexpectedError( $this->conn, 'Cannot close shared connection.' );
 255         }
 256
 257         public function query( $sql, $fname = __METHOD__, $flags = 0 ) {
 258                 return $this->__call( __FUNCTION__, func_get_args() );
 259         }
 260
 261         public function freeResult( $res ) {
 262                 return $this->__call( __FUNCTION__, func_get_args() );
 263         }
 264
 265         public function selectField(
 266                 $table, $var, $cond = '', $fname = __METHOD__, $options = [], $join_conds = []
 267         ) {
 268                 return $this->__call( __FUNCTION__, func_get_args() );
 269         }
 270
 271         public function selectFieldValues(
 272                 $table, $var, $cond = '', $fname = __METHOD__, $options = [], $join_conds = []
 273         ) {
 274                 return $this->__call( __FUNCTION__, func_get_args() );
 275         }
 276
 277         public function select(
 278                 $table, $vars, $conds = '', $fname = __METHOD__,
 279                 $options = [], $join_conds = []
 280         ) {
 281                 return $this->__call( __FUNCTION__, func_get_args() );
 282         }
 283
 284         public function selectSQLText(
 285                 $table, $vars, $conds = '', $fname = __METHOD__,
 286                 $options = [], $join_conds = []
 287         ) {
 288                 return $this->__call( __FUNCTION__, func_get_args() );
 289         }
 290
 291         public function selectRow(
 292                 $table, $vars, $conds, $fname = __METHOD__,
 293                 $options = [], $join_conds = []
 294         ) {
 295                 return $this->__call( __FUNCTION__, func_get_args() );
 296         }
 297
 298         public function estimateRowCount(
 299                 $table, $vars = '*', $conds = '', $fname = __METHOD__, $options = [], $join_conds = []
 300         ) {
 301                 return $this->__call( __FUNCTION__, func_get_args() );
 302         }
 303
 304         public function selectRowCount(
 305                 $tables, $vars = '*', $conds = '', $fname = __METHOD__, $options = [], $join_conds = []
 306         ) {
 307                 return $this->__call( __FUNCTION__, func_get_args() );
 308         }
 309
 310         public function lockForUpdate(
 311                 $table, $conds = '', $fname = __METHOD__, $options = [], $join_conds = []
 312         ) {
 313                 return $this->__call( __FUNCTION__, func_get_args() );
 314         }
 315
 316         public function fieldExists( $table, $field, $fname = __METHOD__ ) {
 317                 return $this->__call( __FUNCTION__, func_get_args() );
 318         }
 319
 320         public function indexExists( $table, $index, $fname = __METHOD__ ) {
 321                 return $this->__call( __FUNCTION__, func_get_args() );
 322         }
 323
 324         public function tableExists( $table, $fname = __METHOD__ ) {
 325                 return $this->__call( __FUNCTION__, func_get_args() );
 326         }
 327
 328         public function insert( $table, $a, $fname = __METHOD__, $options = [] ) {
 329                 return $this->__call( __FUNCTION__, func_get_args() );
 330         }
 331
 332         public function update( $table, $values, $conds, $fname = __METHOD__, $options = [] ) {
 333                 return $this->__call( __FUNCTION__, func_get_args() );
 334         }
 335
 336         public function makeList( $a, $mode = self::LIST_COMMA ) {
 337                 return $this->__call( __FUNCTION__, func_get_args() );
 338         }
 339
 340         public function makeWhereFrom2d( $data, $baseKey, $subKey ) {
 341                 return $this->__call( __FUNCTION__, func_get_args() );
 342         }
 343
 344         public function aggregateValue( $valuedata, $valuename = 'value' ) {
 345                 return $this->__call( __FUNCTION__, func_get_args() );
 346         }
 347
 348         public function bitNot( $field ) {
 349                 return $this->__call( __FUNCTION__, func_get_args() );
 350         }
 351
 352         public function bitAnd( $fieldLeft, $fieldRight ) {
 353                 return $this->__call( __FUNCTION__, func_get_args() );
 354         }
 355
 356         public function bitOr( $fieldLeft, $fieldRight ) {
 357                 return $this->__call( __FUNCTION__, func_get_args() );
 358         }
 359
 360         public function buildConcat( $stringList ) {
 361                 return $this->__call( __FUNCTION__, func_get_args() );
 362         }
 363
 364         public function buildGroupConcatField(
 365                 $delim, $table, $field, $conds = '', $join_conds = []
 366         ) {
 367                 return $this->__call( __FUNCTION__, func_get_args() );
 368         }
 369
 370         public function buildSubstring( $input, $startPosition, $length = null ) {
 371                 return $this->__call( __FUNCTION__, func_get_args() );
 372         }
 373
 374         public function buildStringCast( $field ) {
 375                 return $this->__call( __FUNCTION__, func_get_args() );
 376         }
 377
 378         public function buildIntegerCast( $field ) {
 379                 return $this->__call( __FUNCTION__, func_get_args() );
 380         }
 381
 382         public function buildSelectSubquery(
 383                 $table, $vars, $conds = '', $fname = __METHOD__,
 384                 $options = [], $join_conds = []
 385         ) {
 386                 return $this->__call( __FUNCTION__, func_get_args() );
 387         }
 388
 389         public function databasesAreIndependent() {
 390                 return $this->__call( __FUNCTION__, func_get_args() );
 391         }
 392
 393         public function selectDB( $db ) {
 394                 // Disallow things that might confuse the LoadBalancer tracking
 395                 throw new DBUnexpectedError( $this, "Database selection is disallowed to enable reuse." );
 396         }
 397
 398         public function selectDomain( $domain ) {
 399                 // Disallow things that might confuse the LoadBalancer tracking
 400                 throw new DBUnexpectedError( $this, "Database selection is disallowed to enable reuse." );
 401         }
 402
 403         public function getDBname() {
 404                 if ( $this->conn === null ) {
 405                         $domain = DatabaseDomain::newFromId( $this->params[self::FLD_DOMAIN] );
 406                         // Avoid triggering a database connection
 407                         return $domain->getDatabase();
 408                 }
 409
 410                 return $this->__call( __FUNCTION__, func_get_args() );
 411         }
 412
 413         public function getServer() {
 414                 return $this->__call( __FUNCTION__, func_get_args() );
 415         }
 416
 417         public function addQuotes( $s ) {
 418                 return $this->__call( __FUNCTION__, func_get_args() );
 419         }
 420
 421         public function addIdentifierQuotes( $s ) {
 422                 return $this->__call( __FUNCTION__, func_get_args() );
 423         }
 424
 425         public function buildLike() {
 426                 return $this->__call( __FUNCTION__, func_get_args() );
 427         }
 428
 429         public function anyChar() {
 430                 return $this->__call( __FUNCTION__, func_get_args() );
 431         }
 432
 433         public function anyString() {
 434                 return $this->__call( __FUNCTION__, func_get_args() );
 435         }
 436
 437         public function nextSequenceValue( $seqName ) {
 438                 return $this->__call( __FUNCTION__, func_get_args() );
 439         }
 440
 441         public function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__ ) {
 442                 return $this->__call( __FUNCTION__, func_get_args() );
 443         }
 444
 445         public function upsert(
 446                 $table, array $rows, $uniqueIndexes, array $set, $fname = __METHOD__
 447         ) {
 448                 return $this->__call( __FUNCTION__, func_get_args() );
 449         }
 450
 451         public function deleteJoin(
 452                 $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = __METHOD__
 453         ) {
 454                 return $this->__call( __FUNCTION__, func_get_args() );
 455         }
 456
 457         public function delete( $table, $conds, $fname = __METHOD__ ) {
 458                 return $this->__call( __FUNCTION__, func_get_args() );
 459         }
 460
 461         public function insertSelect(
 462                 $destTable, $srcTable, $varMap, $conds,
 463                 $fname = __METHOD__, $insertOptions = [], $selectOptions = [], $selectJoinConds = []
 464         ) {
 465                 return $this->__call( __FUNCTION__, func_get_args() );
 466         }
 467
 468         public function unionSupportsOrderAndLimit() {
 469                 return $this->__call( __FUNCTION__, func_get_args() );
 470         }
 471
 472         public function unionQueries( $sqls, $all ) {
 473                 return $this->__call( __FUNCTION__, func_get_args() );
 474         }
 475
 476         public function unionConditionPermutations(
 477                 $table, $vars, array $permute_conds, $extra_conds = '', $fname = __METHOD__,
 478                 $options = [], $join_conds = []
 479         ) {
 480                 return $this->__call( __FUNCTION__, func_get_args() );
 481         }
 482
 483         public function conditional( $cond, $trueVal, $falseVal ) {
 484                 return $this->__call( __FUNCTION__, func_get_args() );
 485         }
 486
 487         public function strreplace( $orig, $old, $new ) {
 488                 return $this->__call( __FUNCTION__, func_get_args() );
 489         }
 490
 491         public function getServerUptime() {
 492                 return $this->__call( __FUNCTION__, func_get_args() );
 493         }
 494
 495         public function wasDeadlock() {
 496                 return $this->__call( __FUNCTION__, func_get_args() );
 497         }
 498
 499         public function wasLockTimeout() {
 500                 return $this->__call( __FUNCTION__, func_get_args() );
 501         }
 502
 503         public function wasConnectionLoss() {
 504                 return $this->__call( __FUNCTION__, func_get_args() );
 505         }
 506
 507         public function wasReadOnlyError() {
 508                 return $this->__call( __FUNCTION__, func_get_args() );
 509         }
 510
 511         public function wasErrorReissuable() {
 512                 return $this->__call( __FUNCTION__, func_get_args() );
 513         }
 514
 515         public function masterPosWait( DBMasterPos $pos, $timeout ) {
 516                 return $this->__call( __FUNCTION__, func_get_args() );
 517         }
 518
 519         public function getReplicaPos() {
 520                 return $this->__call( __FUNCTION__, func_get_args() );
 521         }
 522
 523         public function getMasterPos() {
 524                 return $this->__call( __FUNCTION__, func_get_args() );
 525         }
 526
 527         public function serverIsReadOnly() {
 528                 return $this->__call( __FUNCTION__, func_get_args() );
 529         }
 530
 531         public function onTransactionResolution( callable $callback, $fname = __METHOD__ ) {
 532                 return $this->__call( __FUNCTION__, func_get_args() );
 533         }
 534
 535         public function onTransactionCommitOrIdle( callable $callback, $fname = __METHOD__ ) {
 536                 return $this->__call( __FUNCTION__, func_get_args() );
 537         }
 538
 539         public function onTransactionIdle( callable $callback, $fname = __METHOD__ ) {
 540                 return $this->__call( __FUNCTION__, func_get_args() );
 541         }
 542
 543         public function onTransactionPreCommitOrIdle( callable $callback, $fname = __METHOD__ ) {
 544                 return $this->__call( __FUNCTION__, func_get_args() );
 545         }
 546
 547         public function setTransactionListener( $name, callable $callback = null ) {
 548                 return $this->__call( __FUNCTION__, func_get_args() );
 549         }
 550
 551         public function startAtomic(
 552                 $fname = __METHOD__, $cancelable = IDatabase::ATOMIC_NOT_CANCELABLE
 553         ) {
 554                 return $this->__call( __FUNCTION__, func_get_args() );
 555         }
 556
 557         public function endAtomic( $fname = __METHOD__ ) {
 558                 return $this->__call( __FUNCTION__, func_get_args() );
 559         }
 560
 561         public function cancelAtomic( $fname = __METHOD__, AtomicSectionIdentifier $sectionId = null ) {
 562                 return $this->__call( __FUNCTION__, func_get_args() );
 563         }
 564
 565         public function doAtomicSection(
 566                 $fname, callable $callback, $cancelable = self::ATOMIC_NOT_CANCELABLE
 567         ) {
 568                 return $this->__call( __FUNCTION__, func_get_args() );
 569         }
 570
 571         public function begin( $fname = __METHOD__, $mode = IDatabase::TRANSACTION_EXPLICIT ) {
 572                 return $this->__call( __FUNCTION__, func_get_args() );
 573         }
 574
 575         public function commit( $fname = __METHOD__, $flush = '' ) {
 576                 return $this->__call( __FUNCTION__, func_get_args() );
 577         }
 578
 579         public function rollback( $fname = __METHOD__, $flush = '' ) {
 580                 return $this->__call( __FUNCTION__, func_get_args() );
 581         }
 582
 583         public function flushSnapshot( $fname = __METHOD__ ) {
 584                 return $this->__call( __FUNCTION__, func_get_args() );
 585         }
 586
 587         public function timestamp( $ts = 0 ) {
 588                 return $this->__call( __FUNCTION__, func_get_args() );
 589         }
 590
 591         public function timestampOrNull( $ts = null ) {
 592                 return $this->__call( __FUNCTION__, func_get_args() );
 593         }
 594
 595         public function ping( &$rtt = null ) {
 596                 return func_num_args()
 597                         ? $this->__call( __FUNCTION__, [ &$rtt ] )
 598                         : $this->__call( __FUNCTION__, [] ); // method cares about null vs missing
 599         }
 600
 601         public function getLag() {
 602                 return $this->__call( __FUNCTION__, func_get_args() );
 603         }
 604
 605         public function getSessionLagStatus() {
 606                 return $this->__call( __FUNCTION__, func_get_args() );
 607         }
 608
 609         public function maxListLen() {
 610                 return $this->__call( __FUNCTION__, func_get_args() );
 611         }
 612
 613         public function encodeBlob( $b ) {
 614                 return $this->__call( __FUNCTION__, func_get_args() );
 615         }
 616
 617         public function decodeBlob( $b ) {
 618                 return $this->__call( __FUNCTION__, func_get_args() );
 619         }
 620
 621         public function setSessionOptions( array $options ) {
 622                 return $this->__call( __FUNCTION__, func_get_args() );
 623         }
 624
 625         public function setSchemaVars( $vars ) {
 626                 return $this->__call( __FUNCTION__, func_get_args() );
 627         }
 628
 629         public function lockIsFree( $lockName, $method ) {
 630                 return $this->__call( __FUNCTION__, func_get_args() );
 631         }
 632
 633         public function lock( $lockName, $method, $timeout = 5 ) {
 634                 return $this->__call( __FUNCTION__, func_get_args() );
 635         }
 636
 637         public function unlock( $lockName, $method ) {
 638                 return $this->__call( __FUNCTION__, func_get_args() );
 639         }
 640
 641         public function getScopedLockAndFlush( $lockKey, $fname, $timeout ) {
 642                 return $this->__call( __FUNCTION__, func_get_args() );
 643         }
 644
 645         public function namedLocksEnqueue() {
 646                 return $this->__call( __FUNCTION__, func_get_args() );
 647         }
 648
 649         public function getInfinity() {
 650                 return $this->__call( __FUNCTION__, func_get_args() );
 651         }
 652
 653         public function encodeExpiry( $expiry ) {
 654                 return $this->__call( __FUNCTION__, func_get_args() );
 655         }
 656
 657         public function decodeExpiry( $expiry, $format = TS_MW ) {
 658                 return $this->__call( __FUNCTION__, func_get_args() );
 659         }
 660
 661         public function setBigSelects( $value = true ) {
 662                 return $this->__call( __FUNCTION__, func_get_args() );
 663         }
 664
 665         public function isReadOnly() {
 666                 return $this->__call( __FUNCTION__, func_get_args() );
 667         }
 668
 669         public function setTableAliases( array $aliases ) {
 670                 return $this->__call( __FUNCTION__, func_get_args() );
 671         }
 672
 673         public function setIndexAliases( array $aliases ) {
 674                 return $this->__call( __FUNCTION__, func_get_args() );
 675         }
 676
 677         /**
 678          * Clean up the connection when out of scope
 679          */
 680         function __destruct() {
 681                 if ( $this->conn ) {
 682                         $this->lb->reuseConnection( $this->conn );
 683                 }
 684         }
 685 }
 686
 687 /**
 688  * @since 1.22
 689  * @deprecated since 1.29
 690  */
 691 class_alias( DBConnRef::class, 'DBConnRef' );