includes/db/DatabaseMysqlBase.php

   1 <?php
   2 /**
   3  * This is the MySQL database abstraction layer.
   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 Database
  22  */
  23
  24 /**
  25  * Database abstraction object for MySQL.
  26  * Defines methods independent on used MySQL extension.
  27  *
  28  * @ingroup Database
  29  * @since 1.22
  30  * @see Database
  31  */
  32 abstract class DatabaseMysqlBase extends Database {
  33         /** @var MysqlMasterPos */
  34         protected $lastKnownSlavePos;
  35         /** @var string Method to detect slave lag */
  36         protected $lagDetectionMethod;
  37         /** @var array Method to detect slave lag */
  38         protected $lagDetectionOptions = [];
  39         /** @var bool bool Whether to use GTID methods */
  40         protected $useGTIDs = false;
  41
  42         /** @var string|null */
  43         private $serverVersion = null;
  44
  45         /**
  46          * Additional $params include:
  47          *   - lagDetectionMethod : set to one of (Seconds_Behind_Master,pt-heartbeat).
  48          *       pt-heartbeat assumes the table is at heartbeat.heartbeat
  49          *       and uses UTC timestamps in the heartbeat.ts column.
  50          *       (https://www.percona.com/doc/percona-toolkit/2.2/pt-heartbeat.html)
  51          *   - lagDetectionOptions : if using pt-heartbeat, this can be set to an array map to change
  52          *       the default behavior. Normally, the heartbeat row with the server
  53          *       ID of this server's master will be used. Set the "conds" field to
  54          *       override the query conditions, e.g. ['shard' => 's1'].
  55          *   - useGTIDs : use GTID methods like MASTER_GTID_WAIT() when possible.
  56          * @param array $params
  57          */
  58         function __construct( array $params ) {
  59                 parent::__construct( $params );
  60
  61                 $this->lagDetectionMethod = isset( $params['lagDetectionMethod'] )
  62                         ? $params['lagDetectionMethod']
  63                         : 'Seconds_Behind_Master';
  64                 $this->lagDetectionOptions = isset( $params['lagDetectionOptions'] )
  65                         ? $params['lagDetectionOptions']
  66                         : [];
  67                 $this->useGTIDs = !empty( $params['useGTIDs' ] );
  68         }
  69
  70         /**
  71          * @return string
  72          */
  73         function getType() {
  74                 return 'mysql';
  75         }
  76
  77         /**
  78          * @param string $server
  79          * @param string $user
  80          * @param string $password
  81          * @param string $dbName
  82          * @throws Exception|DBConnectionError
  83          * @return bool
  84          */
  85         function open( $server, $user, $password, $dbName ) {
  86                 global $wgAllDBsAreLocalhost, $wgSQLMode;
  87
  88                 # Close/unset connection handle
  89                 $this->close();
  90
  91                 # Debugging hack -- fake cluster
  92                 $realServer = $wgAllDBsAreLocalhost ? 'localhost' : $server;
  93                 $this->mServer = $server;
  94                 $this->mUser = $user;
  95                 $this->mPassword = $password;
  96                 $this->mDBname = $dbName;
  97
  98                 $this->installErrorHandler();
  99                 try {
 100                         $this->mConn = $this->mysqlConnect( $realServer );
 101                 } catch ( Exception $ex ) {
 102                         $this->restoreErrorHandler();
 103                         throw $ex;
 104                 }
 105                 $error = $this->restoreErrorHandler();
 106
 107                 # Always log connection errors
 108                 if ( !$this->mConn ) {
 109                         if ( !$error ) {
 110                                 $error = $this->lastError();
 111                         }
 112                         wfLogDBError(
 113                                 "Error connecting to {db_server}: {error}",
 114                                 $this->getLogContext( [
 115                                         'method' => __METHOD__,
 116                                         'error' => $error,
 117                                 ] )
 118                         );
 119                         wfDebug( "DB connection error\n" .
 120                                 "Server: $server, User: $user, Password: " .
 121                                 substr( $password, 0, 3 ) . "..., error: " . $error . "\n" );
 122
 123                         $this->reportConnectionError( $error );
 124                 }
 125
 126                 if ( $dbName != '' ) {
 127                         MediaWiki\suppressWarnings();
 128                         $success = $this->selectDB( $dbName );
 129                         MediaWiki\restoreWarnings();
 130                         if ( !$success ) {
 131                                 wfLogDBError(
 132                                         "Error selecting database {db_name} on server {db_server}",
 133                                         $this->getLogContext( [
 134                                                 'method' => __METHOD__,
 135                                         ] )
 136                                 );
 137                                 wfDebug( "Error selecting database $dbName on server {$this->mServer} " .
 138                                         "from client host " . wfHostname() . "\n" );
 139
 140                                 $this->reportConnectionError( "Error selecting database $dbName" );
 141                         }
 142                 }
 143
 144                 // Tell the server what we're communicating with
 145                 if ( !$this->connectInitCharset() ) {
 146                         $this->reportConnectionError( "Error setting character set" );
 147                 }
 148
 149                 // Abstract over any insane MySQL defaults
 150                 $set = [ 'group_concat_max_len = 262144' ];
 151                 // Set SQL mode, default is turning them all off, can be overridden or skipped with null
 152                 if ( is_string( $wgSQLMode ) ) {
 153                         $set[] = 'sql_mode = ' . $this->addQuotes( $wgSQLMode );
 154                 }
 155                 // Set any custom settings defined by site config
 156                 // (e.g. https://dev.mysql.com/doc/refman/4.1/en/innodb-parameters.html)
 157                 foreach ( $this->mSessionVars as $var => $val ) {
 158                         // Escape strings but not numbers to avoid MySQL complaining
 159                         if ( !is_int( $val ) && !is_float( $val ) ) {
 160                                 $val = $this->addQuotes( $val );
 161                         }
 162                         $set[] = $this->addIdentifierQuotes( $var ) . ' = ' . $val;
 163                 }
 164
 165                 if ( $set ) {
 166                         // Use doQuery() to avoid opening implicit transactions (DBO_TRX)
 167                         $success = $this->doQuery( 'SET ' . implode( ', ', $set ) );
 168                         if ( !$success ) {
 169                                 wfLogDBError(
 170                                         'Error setting MySQL variables on server {db_server} (check $wgSQLMode)',
 171                                         $this->getLogContext( [
 172                                                 'method' => __METHOD__,
 173                                         ] )
 174                                 );
 175                                 $this->reportConnectionError(
 176                                         'Error setting MySQL variables on server {db_server} (check $wgSQLMode)' );
 177                         }
 178                 }
 179
 180                 $this->mOpened = true;
 181
 182                 return true;
 183         }
 184
 185         /**
 186          * Set the character set information right after connection
 187          * @return bool
 188          */
 189         protected function connectInitCharset() {
 190                 global $wgDBmysql5;
 191
 192                 if ( $wgDBmysql5 ) {
 193                         // Tell the server we're communicating with it in UTF-8.
 194                         // This may engage various charset conversions.
 195                         return $this->mysqlSetCharset( 'utf8' );
 196                 } else {
 197                         return $this->mysqlSetCharset( 'binary' );
 198                 }
 199         }
 200
 201         /**
 202          * Open a connection to a MySQL server
 203          *
 204          * @param string $realServer
 205          * @return mixed Raw connection
 206          * @throws DBConnectionError
 207          */
 208         abstract protected function mysqlConnect( $realServer );
 209
 210         /**
 211          * Set the character set of the MySQL link
 212          *
 213          * @param string $charset
 214          * @return bool
 215          */
 216         abstract protected function mysqlSetCharset( $charset );
 217
 218         /**
 219          * @param ResultWrapper|resource $res
 220          * @throws DBUnexpectedError
 221          */
 222         function freeResult( $res ) {
 223                 if ( $res instanceof ResultWrapper ) {
 224                         $res = $res->result;
 225                 }
 226                 MediaWiki\suppressWarnings();
 227                 $ok = $this->mysqlFreeResult( $res );
 228                 MediaWiki\restoreWarnings();
 229                 if ( !$ok ) {
 230                         throw new DBUnexpectedError( $this, "Unable to free MySQL result" );
 231                 }
 232         }
 233
 234         /**
 235          * Free result memory
 236          *
 237          * @param resource $res Raw result
 238          * @return bool
 239          */
 240         abstract protected function mysqlFreeResult( $res );
 241
 242         /**
 243          * @param ResultWrapper|resource $res
 244          * @return stdClass|bool
 245          * @throws DBUnexpectedError
 246          */
 247         function fetchObject( $res ) {
 248                 if ( $res instanceof ResultWrapper ) {
 249                         $res = $res->result;
 250                 }
 251                 MediaWiki\suppressWarnings();
 252                 $row = $this->mysqlFetchObject( $res );
 253                 MediaWiki\restoreWarnings();
 254
 255                 $errno = $this->lastErrno();
 256                 // Unfortunately, mysql_fetch_object does not reset the last errno.
 257                 // Only check for CR_SERVER_LOST and CR_UNKNOWN_ERROR, as
 258                 // these are the only errors mysql_fetch_object can cause.
 259                 // See http://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
 260                 if ( $errno == 2000 || $errno == 2013 ) {
 261                         throw new DBUnexpectedError(
 262                                 $this,
 263                                 'Error in fetchObject(): ' . htmlspecialchars( $this->lastError() )
 264                         );
 265                 }
 266
 267                 return $row;
 268         }
 269
 270         /**
 271          * Fetch a result row as an object
 272          *
 273          * @param resource $res Raw result
 274          * @return stdClass
 275          */
 276         abstract protected function mysqlFetchObject( $res );
 277
 278         /**
 279          * @param ResultWrapper|resource $res
 280          * @return array|bool
 281          * @throws DBUnexpectedError
 282          */
 283         function fetchRow( $res ) {
 284                 if ( $res instanceof ResultWrapper ) {
 285                         $res = $res->result;
 286                 }
 287                 MediaWiki\suppressWarnings();
 288                 $row = $this->mysqlFetchArray( $res );
 289                 MediaWiki\restoreWarnings();
 290
 291                 $errno = $this->lastErrno();
 292                 // Unfortunately, mysql_fetch_array does not reset the last errno.
 293                 // Only check for CR_SERVER_LOST and CR_UNKNOWN_ERROR, as
 294                 // these are the only errors mysql_fetch_array can cause.
 295                 // See http://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
 296                 if ( $errno == 2000 || $errno == 2013 ) {
 297                         throw new DBUnexpectedError(
 298                                 $this,
 299                                 'Error in fetchRow(): ' . htmlspecialchars( $this->lastError() )
 300                         );
 301                 }
 302
 303                 return $row;
 304         }
 305
 306         /**
 307          * Fetch a result row as an associative and numeric array
 308          *
 309          * @param resource $res Raw result
 310          * @return array
 311          */
 312         abstract protected function mysqlFetchArray( $res );
 313
 314         /**
 315          * @throws DBUnexpectedError
 316          * @param ResultWrapper|resource $res
 317          * @return int
 318          */
 319         function numRows( $res ) {
 320                 if ( $res instanceof ResultWrapper ) {
 321                         $res = $res->result;
 322                 }
 323                 MediaWiki\suppressWarnings();
 324                 $n = $this->mysqlNumRows( $res );
 325                 MediaWiki\restoreWarnings();
 326
 327                 // Unfortunately, mysql_num_rows does not reset the last errno.
 328                 // We are not checking for any errors here, since
 329                 // these are no errors mysql_num_rows can cause.
 330                 // See http://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
 331                 // See https://phabricator.wikimedia.org/T44430
 332                 return $n;
 333         }
 334
 335         /**
 336          * Get number of rows in result
 337          *
 338          * @param resource $res Raw result
 339          * @return int
 340          */
 341         abstract protected function mysqlNumRows( $res );
 342
 343         /**
 344          * @param ResultWrapper|resource $res
 345          * @return int
 346          */
 347         function numFields( $res ) {
 348                 if ( $res instanceof ResultWrapper ) {
 349                         $res = $res->result;
 350                 }
 351
 352                 return $this->mysqlNumFields( $res );
 353         }
 354
 355         /**
 356          * Get number of fields in result
 357          *
 358          * @param resource $res Raw result
 359          * @return int
 360          */
 361         abstract protected function mysqlNumFields( $res );
 362
 363         /**
 364          * @param ResultWrapper|resource $res
 365          * @param int $n
 366          * @return string
 367          */
 368         function fieldName( $res, $n ) {
 369                 if ( $res instanceof ResultWrapper ) {
 370                         $res = $res->result;
 371                 }
 372
 373                 return $this->mysqlFieldName( $res, $n );
 374         }
 375
 376         /**
 377          * Get the name of the specified field in a result
 378          *
 379          * @param ResultWrapper|resource $res
 380          * @param int $n
 381          * @return string
 382          */
 383         abstract protected function mysqlFieldName( $res, $n );
 384
 385         /**
 386          * mysql_field_type() wrapper
 387          * @param ResultWrapper|resource $res
 388          * @param int $n
 389          * @return string
 390          */
 391         public function fieldType( $res, $n ) {
 392                 if ( $res instanceof ResultWrapper ) {
 393                         $res = $res->result;
 394                 }
 395
 396                 return $this->mysqlFieldType( $res, $n );
 397         }
 398
 399         /**
 400          * Get the type of the specified field in a result
 401          *
 402          * @param ResultWrapper|resource $res
 403          * @param int $n
 404          * @return string
 405          */
 406         abstract protected function mysqlFieldType( $res, $n );
 407
 408         /**
 409          * @param ResultWrapper|resource $res
 410          * @param int $row
 411          * @return bool
 412          */
 413         function dataSeek( $res, $row ) {
 414                 if ( $res instanceof ResultWrapper ) {
 415                         $res = $res->result;
 416                 }
 417
 418                 return $this->mysqlDataSeek( $res, $row );
 419         }
 420
 421         /**
 422          * Move internal result pointer
 423          *
 424          * @param ResultWrapper|resource $res
 425          * @param int $row
 426          * @return bool
 427          */
 428         abstract protected function mysqlDataSeek( $res, $row );
 429
 430         /**
 431          * @return string
 432          */
 433         function lastError() {
 434                 if ( $this->mConn ) {
 435                         # Even if it's non-zero, it can still be invalid
 436                         MediaWiki\suppressWarnings();
 437                         $error = $this->mysqlError( $this->mConn );
 438                         if ( !$error ) {
 439                                 $error = $this->mysqlError();
 440                         }
 441                         MediaWiki\restoreWarnings();
 442                 } else {
 443                         $error = $this->mysqlError();
 444                 }
 445                 if ( $error ) {
 446                         $error .= ' (' . $this->mServer . ')';
 447                 }
 448
 449                 return $error;
 450         }
 451
 452         /**
 453          * Returns the text of the error message from previous MySQL operation
 454          *
 455          * @param resource $conn Raw connection
 456          * @return string
 457          */
 458         abstract protected function mysqlError( $conn = null );
 459
 460         /**
 461          * @param string $table
 462          * @param array $uniqueIndexes
 463          * @param array $rows
 464          * @param string $fname
 465          * @return ResultWrapper
 466          */
 467         function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__ ) {
 468                 return $this->nativeReplace( $table, $rows, $fname );
 469         }
 470
 471         /**
 472          * Estimate rows in dataset
 473          * Returns estimated count, based on EXPLAIN output
 474          * Takes same arguments as Database::select()
 475          *
 476          * @param string|array $table
 477          * @param string|array $vars
 478          * @param string|array $conds
 479          * @param string $fname
 480          * @param string|array $options
 481          * @return bool|int
 482          */
 483         public function estimateRowCount( $table, $vars = '*', $conds = '',
 484                 $fname = __METHOD__, $options = []
 485         ) {
 486                 $options['EXPLAIN'] = true;
 487                 $res = $this->select( $table, $vars, $conds, $fname, $options );
 488                 if ( $res === false ) {
 489                         return false;
 490                 }
 491                 if ( !$this->numRows( $res ) ) {
 492                         return 0;
 493                 }
 494
 495                 $rows = 1;
 496                 foreach ( $res as $plan ) {
 497                         $rows *= $plan->rows > 0 ? $plan->rows : 1; // avoid resetting to zero
 498                 }
 499
 500                 return (int)$rows;
 501         }
 502
 503         /**
 504          * @param string $table
 505          * @param string $field
 506          * @return bool|MySQLField
 507          */
 508         function fieldInfo( $table, $field ) {
 509                 $table = $this->tableName( $table );
 510                 $res = $this->query( "SELECT * FROM $table LIMIT 1", __METHOD__, true );
 511                 if ( !$res ) {
 512                         return false;
 513                 }
 514                 $n = $this->mysqlNumFields( $res->result );
 515                 for ( $i = 0; $i < $n; $i++ ) {
 516                         $meta = $this->mysqlFetchField( $res->result, $i );
 517                         if ( $field == $meta->name ) {
 518                                 return new MySQLField( $meta );
 519                         }
 520                 }
 521
 522                 return false;
 523         }
 524
 525         /**
 526          * Get column information from a result
 527          *
 528          * @param resource $res Raw result
 529          * @param int $n
 530          * @return stdClass
 531          */
 532         abstract protected function mysqlFetchField( $res, $n );
 533
 534         /**
 535          * Get information about an index into an object
 536          * Returns false if the index does not exist
 537          *
 538          * @param string $table
 539          * @param string $index
 540          * @param string $fname
 541          * @return bool|array|null False or null on failure
 542          */
 543         function indexInfo( $table, $index, $fname = __METHOD__ ) {
 544                 # SHOW INDEX works in MySQL 3.23.58, but SHOW INDEXES does not.
 545                 # SHOW INDEX should work for 3.x and up:
 546                 # http://dev.mysql.com/doc/mysql/en/SHOW_INDEX.html
 547                 $table = $this->tableName( $table );
 548                 $index = $this->indexName( $index );
 549
 550                 $sql = 'SHOW INDEX FROM ' . $table;
 551                 $res = $this->query( $sql, $fname );
 552
 553                 if ( !$res ) {
 554                         return null;
 555                 }
 556
 557                 $result = [];
 558
 559                 foreach ( $res as $row ) {
 560                         if ( $row->Key_name == $index ) {
 561                                 $result[] = $row;
 562                         }
 563                 }
 564
 565                 return empty( $result ) ? false : $result;
 566         }
 567
 568         /**
 569          * @param string $s
 570          * @return string
 571          */
 572         function strencode( $s ) {
 573                 return $this->mysqlRealEscapeString( $s );
 574         }
 575
 576         /**
 577          * @param string $s
 578          * @return mixed
 579          */
 580         abstract protected function mysqlRealEscapeString( $s );
 581
 582         /**
 583          * MySQL uses `backticks` for identifier quoting instead of the sql standard "double quotes".
 584          *
 585          * @param string $s
 586          * @return string
 587          */
 588         public function addIdentifierQuotes( $s ) {
 589                 // Characters in the range \u0001-\uFFFF are valid in a quoted identifier
 590                 // Remove NUL bytes and escape backticks by doubling
 591                 return '`' . str_replace( [ "\0", '`' ], [ '', '``' ], $s ) . '`';
 592         }
 593
 594         /**
 595          * @param string $name
 596          * @return bool
 597          */
 598         public function isQuotedIdentifier( $name ) {
 599                 return strlen( $name ) && $name[0] == '`' && substr( $name, -1, 1 ) == '`';
 600         }
 601
 602         function getLag() {
 603                 if ( $this->getLagDetectionMethod() === 'pt-heartbeat' ) {
 604                         return $this->getLagFromPtHeartbeat();
 605                 } else {
 606                         return $this->getLagFromSlaveStatus();
 607                 }
 608         }
 609
 610         /**
 611          * @return string
 612          */
 613         protected function getLagDetectionMethod() {
 614                 return $this->lagDetectionMethod;
 615         }
 616
 617         /**
 618          * @return bool|int
 619          */
 620         protected function getLagFromSlaveStatus() {
 621                 $res = $this->query( 'SHOW SLAVE STATUS', __METHOD__ );
 622                 $row = $res ? $res->fetchObject() : false;
 623                 if ( $row && strval( $row->Seconds_Behind_Master ) !== '' ) {
 624                         return intval( $row->Seconds_Behind_Master );
 625                 }
 626
 627                 return false;
 628         }
 629
 630         /**
 631          * @return bool|float
 632          */
 633         protected function getLagFromPtHeartbeat() {
 634                 $options = $this->lagDetectionOptions;
 635
 636                 if ( isset( $options['conds'] ) ) {
 637                         // Best method for multi-DC setups: use logical channel names
 638                         $data = $this->getHeartbeatData( $options['conds'] );
 639                 } else {
 640                         // Standard method: use master server ID (works with stock pt-heartbeat)
 641                         $masterInfo = $this->getMasterServerInfo();
 642                         if ( !$masterInfo ) {
 643                                 wfLogDBError(
 644                                         "Unable to query master of {db_server} for server ID",
 645                                         $this->getLogContext( [
 646                                                 'method' => __METHOD__
 647                                         ] )
 648                                 );
 649
 650                                 return false; // could not get master server ID
 651                         }
 652
 653                         $conds = [ 'server_id' => intval( $masterInfo['serverId'] ) ];
 654                         $data = $this->getHeartbeatData( $conds );
 655                 }
 656
 657                 list( $time, $nowUnix ) = $data;
 658                 if ( $time !== null ) {
 659                         // @time is in ISO format like "2015-09-25T16:48:10.000510"
 660                         $dateTime = new DateTime( $time, new DateTimeZone( 'UTC' ) );
 661                         $timeUnix = (int)$dateTime->format( 'U' ) + $dateTime->format( 'u' ) / 1e6;
 662
 663                         return max( $nowUnix - $timeUnix, 0.0 );
 664                 }
 665
 666                 wfLogDBError(
 667                         "Unable to find pt-heartbeat row for {db_server}",
 668                         $this->getLogContext( [
 669                                 'method' => __METHOD__
 670                         ] )
 671                 );
 672
 673                 return false;
 674         }
 675
 676         protected function getMasterServerInfo() {
 677                 $cache = $this->srvCache;
 678                 $key = $cache->makeGlobalKey(
 679                         'mysql',
 680                         'master-info',
 681                         // Using one key for all cluster slaves is preferable
 682                         $this->getLBInfo( 'clusterMasterHost' ) ?: $this->getServer()
 683                 );
 684
 685                 return $cache->getWithSetCallback(
 686                         $key,
 687                         $cache::TTL_INDEFINITE,
 688                         function () use ( $cache, $key ) {
 689                                 // Get and leave a lock key in place for a short period
 690                                 if ( !$cache->lock( $key, 0, 10 ) ) {
 691                                         return false; // avoid master connection spike slams
 692                                 }
 693
 694                                 $conn = $this->getLazyMasterHandle();
 695                                 if ( !$conn ) {
 696                                         return false; // something is misconfigured
 697                                 }
 698
 699                                 // Connect to and query the master; catch errors to avoid outages
 700                                 try {
 701                                         $res = $conn->query( 'SELECT @@server_id AS id', __METHOD__ );
 702                                         $row = $res ? $res->fetchObject() : false;
 703                                         $id = $row ? (int)$row->id : 0;
 704                                 } catch ( DBError $e ) {
 705                                         $id = 0;
 706                                 }
 707
 708                                 // Cache the ID if it was retrieved
 709                                 return $id ? [ 'serverId' => $id, 'asOf' => time() ] : false;
 710                         }
 711                 );
 712         }
 713
 714         /**
 715          * @param array $conds WHERE clause conditions to find a row
 716          * @return array (heartbeat `ts` column value or null, UNIX timestamp) for the newest beat
 717          * @see https://www.percona.com/doc/percona-toolkit/2.1/pt-heartbeat.html
 718          */
 719         protected function getHeartbeatData( array $conds ) {
 720                 $whereSQL = $this->makeList( $conds, LIST_AND );
 721                 // Use ORDER BY for channel based queries since that field might not be UNIQUE.
 722                 // Note: this would use "TIMESTAMPDIFF(MICROSECOND,ts,UTC_TIMESTAMP(6))" but the
 723                 // percision field is not supported in MySQL <= 5.5.
 724                 $res = $this->query(
 725                         "SELECT ts FROM heartbeat.heartbeat WHERE $whereSQL ORDER BY ts DESC LIMIT 1"
 726                 );
 727                 $row = $res ? $res->fetchObject() : false;
 728
 729                 return [ $row ? $row->ts : null, microtime( true ) ];
 730         }
 731
 732         public function getApproximateLagStatus() {
 733                 if ( $this->getLagDetectionMethod() === 'pt-heartbeat' ) {
 734                         // Disable caching since this is fast enough and we don't wan't
 735                         // to be *too* pessimistic by having both the cache TTL and the
 736                         // pt-heartbeat interval count as lag in getSessionLagStatus()
 737                         return parent::getApproximateLagStatus();
 738                 }
 739
 740                 $key = $this->srvCache->makeGlobalKey( 'mysql-lag', $this->getServer() );
 741                 $approxLag = $this->srvCache->get( $key );
 742                 if ( !$approxLag ) {
 743                         $approxLag = parent::getApproximateLagStatus();
 744                         $this->srvCache->set( $key, $approxLag, 1 );
 745                 }
 746
 747                 return $approxLag;
 748         }
 749
 750         function masterPosWait( DBMasterPos $pos, $timeout ) {
 751                 if ( !( $pos instanceof MySQLMasterPos ) ) {
 752                         throw new InvalidArgumentException( "Position not an instance of MySQLMasterPos" );
 753                 }
 754
 755                 if ( $this->getLBInfo( 'is static' ) === true ) {
 756                         return 0; // this is a copy of a read-only dataset with no master DB
 757                 } elseif ( $this->lastKnownSlavePos && $this->lastKnownSlavePos->hasReached( $pos ) ) {
 758                         return 0; // already reached this point for sure
 759                 }
 760
 761                 // Call doQuery() directly, to avoid opening a transaction if DBO_TRX is set
 762                 if ( $this->useGTIDs && $pos->gtids ) {
 763                         // Wait on the GTID set (MariaDB only)
 764                         $gtidArg = $this->addQuotes( implode( ',', $pos->gtids ) );
 765                         $res = $this->doQuery( "SELECT MASTER_GTID_WAIT($gtidArg, $timeout)" );
 766                 } else {
 767                         // Wait on the binlog coordinates
 768                         $encFile = $this->addQuotes( $pos->file );
 769                         $encPos = intval( $pos->pos );
 770                         $res = $this->doQuery( "SELECT MASTER_POS_WAIT($encFile, $encPos, $timeout)" );
 771                 }
 772
 773                 $row = $res ? $this->fetchRow( $res ) : false;
 774                 if ( !$row ) {
 775                         throw new DBExpectedError( $this, "Failed to query MASTER_POS_WAIT()" );
 776                 }
 777
 778                 // Result can be NULL (error), -1 (timeout), or 0+ per the MySQL manual
 779                 $status = ( $row[0] !== null ) ? intval( $row[0] ) : null;
 780                 if ( $status === null ) {
 781                         // T126436: jobs programmed to wait on master positions might be referencing binlogs
 782                         // with an old master hostname. Such calls make MASTER_POS_WAIT() return null. Try
 783                         // to detect this and treat the slave as having reached the position; a proper master
 784                         // switchover already requires that the new master be caught up before the switch.
 785                         $slavePos = $this->getSlavePos();
 786                         if ( $slavePos && !$slavePos->channelsMatch( $pos ) ) {
 787                                 $this->lastKnownSlavePos = $slavePos;
 788                                 $status = 0;
 789                         }
 790                 } elseif ( $status >= 0 ) {
 791                         // Remember that this position was reached to save queries next time
 792                         $this->lastKnownSlavePos = $pos;
 793                 }
 794
 795                 return $status;
 796         }
 797
 798         /**
 799          * Get the position of the master from SHOW SLAVE STATUS
 800          *
 801          * @return MySQLMasterPos|bool
 802          */
 803         function getSlavePos() {
 804                 $res = $this->query( 'SHOW SLAVE STATUS', __METHOD__ );
 805                 $row = $this->fetchObject( $res );
 806
 807                 if ( $row ) {
 808                         $pos = isset( $row->Exec_master_log_pos )
 809                                 ? $row->Exec_master_log_pos
 810                                 : $row->Exec_Master_Log_Pos;
 811                         // Also fetch the last-applied GTID set (MariaDB)
 812                         if ( $this->useGTIDs ) {
 813                                 $res = $this->query( "SHOW GLOBAL VARIABLES LIKE 'gtid_slave_pos'", __METHOD__ );
 814                                 $gtidRow = $this->fetchObject( $res );
 815                                 $gtidSet = $gtidRow ? $gtidRow->Value : '';
 816                         } else {
 817                                 $gtidSet = '';
 818                         }
 819
 820                         return new MySQLMasterPos( $row->Relay_Master_Log_File, $pos, $gtidSet );
 821                 } else {
 822                         return false;
 823                 }
 824         }
 825
 826         /**
 827          * Get the position of the master from SHOW MASTER STATUS
 828          *
 829          * @return MySQLMasterPos|bool
 830          */
 831         function getMasterPos() {
 832                 $res = $this->query( 'SHOW MASTER STATUS', __METHOD__ );
 833                 $row = $this->fetchObject( $res );
 834
 835                 if ( $row ) {
 836                         // Also fetch the last-written GTID set (MariaDB)
 837                         if ( $this->useGTIDs ) {
 838                                 $res = $this->query( "SHOW GLOBAL VARIABLES LIKE 'gtid_binlog_pos'", __METHOD__ );
 839                                 $gtidRow = $this->fetchObject( $res );
 840                                 $gtidSet = $gtidRow ? $gtidRow->Value : '';
 841                         } else {
 842                                 $gtidSet = '';
 843                         }
 844
 845                         return new MySQLMasterPos( $row->File, $row->Position, $gtidSet );
 846                 } else {
 847                         return false;
 848                 }
 849         }
 850
 851         public function serverIsReadOnly() {
 852                 $res = $this->query( "SHOW GLOBAL VARIABLES LIKE 'read_only'", __METHOD__ );
 853                 $row = $this->fetchObject( $res );
 854
 855                 return $row ? ( strtolower( $row->Value ) === 'on' ) : false;
 856         }
 857
 858         /**
 859          * @param string $index
 860          * @return string
 861          */
 862         function useIndexClause( $index ) {
 863                 return "FORCE INDEX (" . $this->indexName( $index ) . ")";
 864         }
 865
 866         /**
 867          * @return string
 868          */
 869         function lowPriorityOption() {
 870                 return 'LOW_PRIORITY';
 871         }
 872
 873         /**
 874          * @return string
 875          */
 876         public function getSoftwareLink() {
 877                 // MariaDB includes its name in its version string; this is how MariaDB's version of
 878                 // the mysql command-line client identifies MariaDB servers (see mariadb_connection()
 879                 // in libmysql/libmysql.c).
 880                 $version = $this->getServerVersion();
 881                 if ( strpos( $version, 'MariaDB' ) !== false || strpos( $version, '-maria-' ) !== false ) {
 882                         return '[{{int:version-db-mariadb-url}} MariaDB]';
 883                 }
 884
 885                 // Percona Server's version suffix is not very distinctive, and @@version_comment
 886                 // doesn't give the necessary info for source builds, so assume the server is MySQL.
 887                 // (Even Percona's version of mysql doesn't try to make the distinction.)
 888                 return '[{{int:version-db-mysql-url}} MySQL]';
 889         }
 890
 891         /**
 892          * @return string
 893          */
 894         public function getServerVersion() {
 895                 // Not using mysql_get_server_info() or similar for consistency: in the handshake,
 896                 // MariaDB 10 adds the prefix "5.5.5-", and only some newer client libraries strip
 897                 // it off (see RPL_VERSION_HACK in include/mysql_com.h).
 898                 if ( $this->serverVersion === null ) {
 899                         $this->serverVersion = $this->selectField( '', 'VERSION()', '', __METHOD__ );
 900                 }
 901                 return $this->serverVersion;
 902         }
 903
 904         /**
 905          * @param array $options
 906          */
 907         public function setSessionOptions( array $options ) {
 908                 if ( isset( $options['connTimeout'] ) ) {
 909                         $timeout = (int)$options['connTimeout'];
 910                         $this->query( "SET net_read_timeout=$timeout" );
 911                         $this->query( "SET net_write_timeout=$timeout" );
 912                 }
 913         }
 914
 915         /**
 916          * @param string $sql
 917          * @param string $newLine
 918          * @return bool
 919          */
 920         public function streamStatementEnd( &$sql, &$newLine ) {
 921                 if ( strtoupper( substr( $newLine, 0, 9 ) ) == 'DELIMITER' ) {
 922                         preg_match( '/^DELIMITER\s+(\S+)/', $newLine, $m );
 923                         $this->delimiter = $m[1];
 924                         $newLine = '';
 925                 }
 926
 927                 return parent::streamStatementEnd( $sql, $newLine );
 928         }
 929
 930         /**
 931          * Check to see if a named lock is available. This is non-blocking.
 932          *
 933          * @param string $lockName Name of lock to poll
 934          * @param string $method Name of method calling us
 935          * @return bool
 936          * @since 1.20
 937          */
 938         public function lockIsFree( $lockName, $method ) {
 939                 $lockName = $this->addQuotes( $this->makeLockName( $lockName ) );
 940                 $result = $this->query( "SELECT IS_FREE_LOCK($lockName) AS lockstatus", $method );
 941                 $row = $this->fetchObject( $result );
 942
 943                 return ( $row->lockstatus == 1 );
 944         }
 945
 946         /**
 947          * @param string $lockName
 948          * @param string $method
 949          * @param int $timeout
 950          * @return bool
 951          */
 952         public function lock( $lockName, $method, $timeout = 5 ) {
 953                 $lockName = $this->addQuotes( $this->makeLockName( $lockName ) );
 954                 $result = $this->query( "SELECT GET_LOCK($lockName, $timeout) AS lockstatus", $method );
 955                 $row = $this->fetchObject( $result );
 956
 957                 if ( $row->lockstatus == 1 ) {
 958                         parent::lock( $lockName, $method, $timeout ); // record
 959                         return true;
 960                 }
 961
 962                 wfDebug( __METHOD__ . " failed to acquire lock\n" );
 963
 964                 return false;
 965         }
 966
 967         /**
 968          * FROM MYSQL DOCS:
 969          * http://dev.mysql.com/doc/refman/5.0/en/miscellaneous-functions.html#function_release-lock
 970          * @param string $lockName
 971          * @param string $method
 972          * @return bool
 973          */
 974         public function unlock( $lockName, $method ) {
 975                 $lockName = $this->addQuotes( $this->makeLockName( $lockName ) );
 976                 $result = $this->query( "SELECT RELEASE_LOCK($lockName) as lockstatus", $method );
 977                 $row = $this->fetchObject( $result );
 978
 979                 if ( $row->lockstatus == 1 ) {
 980                         parent::unlock( $lockName, $method ); // record
 981                         return true;
 982                 }
 983
 984                 wfDebug( __METHOD__ . " failed to release lock\n" );
 985
 986                 return false;
 987         }
 988
 989         private function makeLockName( $lockName ) {
 990                 // http://dev.mysql.com/doc/refman/5.7/en/miscellaneous-functions.html#function_get-lock
 991                 // Newer version enforce a 64 char length limit.
 992                 return ( strlen( $lockName ) > 64 ) ? sha1( $lockName ) : $lockName;
 993         }
 994
 995         public function namedLocksEnqueue() {
 996                 return true;
 997         }
 998
 999         /**
1000          * @param array $read
1001          * @param array $write
1002          * @param string $method
1003          * @param bool $lowPriority
1004          * @return bool
1005          */
1006         public function lockTables( $read, $write, $method, $lowPriority = true ) {
1007                 $items = [];
1008
1009                 foreach ( $write as $table ) {
1010                         $tbl = $this->tableName( $table ) .
1011                                 ( $lowPriority ? ' LOW_PRIORITY' : '' ) .
1012                                 ' WRITE';
1013                         $items[] = $tbl;
1014                 }
1015                 foreach ( $read as $table ) {
1016                         $items[] = $this->tableName( $table ) . ' READ';
1017                 }
1018                 $sql = "LOCK TABLES " . implode( ',', $items );
1019                 $this->query( $sql, $method );
1020
1021                 return true;
1022         }
1023
1024         /**
1025          * @param string $method
1026          * @return bool
1027          */
1028         public function unlockTables( $method ) {
1029                 $this->query( "UNLOCK TABLES", $method );
1030
1031                 return true;
1032         }
1033
1034         /**
1035          * Get search engine class. All subclasses of this
1036          * need to implement this if they wish to use searching.
1037          *
1038          * @return string
1039          */
1040         public function getSearchEngine() {
1041                 return 'SearchMySQL';
1042         }
1043
1044         /**
1045          * @param bool $value
1046          */
1047         public function setBigSelects( $value = true ) {
1048                 if ( $value === 'default' ) {
1049                         if ( $this->mDefaultBigSelects === null ) {
1050                                 # Function hasn't been called before so it must already be set to the default
1051                                 return;
1052                         } else {
1053                                 $value = $this->mDefaultBigSelects;
1054                         }
1055                 } elseif ( $this->mDefaultBigSelects === null ) {
1056                         $this->mDefaultBigSelects =
1057                                 (bool)$this->selectField( false, '@@sql_big_selects', '', __METHOD__ );
1058                 }
1059                 $encValue = $value ? '1' : '0';
1060                 $this->query( "SET sql_big_selects=$encValue", __METHOD__ );
1061         }
1062
1063         /**
1064          * DELETE where the condition is a join. MySql uses multi-table deletes.
1065          * @param string $delTable
1066          * @param string $joinTable
1067          * @param string $delVar
1068          * @param string $joinVar
1069          * @param array|string $conds
1070          * @param bool|string $fname
1071          * @throws DBUnexpectedError
1072          * @return bool|ResultWrapper
1073          */
1074         function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = __METHOD__ ) {
1075                 if ( !$conds ) {
1076                         throw new DBUnexpectedError( $this, 'DatabaseBase::deleteJoin() called with empty $conds' );
1077                 }
1078
1079                 $delTable = $this->tableName( $delTable );
1080                 $joinTable = $this->tableName( $joinTable );
1081                 $sql = "DELETE $delTable FROM $delTable, $joinTable WHERE $delVar=$joinVar ";
1082
1083                 if ( $conds != '*' ) {
1084                         $sql .= ' AND ' . $this->makeList( $conds, LIST_AND );
1085                 }
1086
1087                 return $this->query( $sql, $fname );
1088         }
1089
1090         /**
1091          * @param string $table
1092          * @param array $rows
1093          * @param array $uniqueIndexes
1094          * @param array $set
1095          * @param string $fname
1096          * @return bool
1097          */
1098         public function upsert( $table, array $rows, array $uniqueIndexes,
1099                 array $set, $fname = __METHOD__
1100         ) {
1101                 if ( !count( $rows ) ) {
1102                         return true; // nothing to do
1103                 }
1104
1105                 if ( !is_array( reset( $rows ) ) ) {
1106                         $rows = [ $rows ];
1107                 }
1108
1109                 $table = $this->tableName( $table );
1110                 $columns = array_keys( $rows[0] );
1111
1112                 $sql = "INSERT INTO $table (" . implode( ',', $columns ) . ') VALUES ';
1113                 $rowTuples = [];
1114                 foreach ( $rows as $row ) {
1115                         $rowTuples[] = '(' . $this->makeList( $row ) . ')';
1116                 }
1117                 $sql .= implode( ',', $rowTuples );
1118                 $sql .= " ON DUPLICATE KEY UPDATE " . $this->makeList( $set, LIST_SET );
1119
1120                 return (bool)$this->query( $sql, $fname );
1121         }
1122
1123         /**
1124          * Determines how long the server has been up
1125          *
1126          * @return int
1127          */
1128         function getServerUptime() {
1129                 $vars = $this->getMysqlStatus( 'Uptime' );
1130
1131                 return (int)$vars['Uptime'];
1132         }
1133
1134         /**
1135          * Determines if the last failure was due to a deadlock
1136          *
1137          * @return bool
1138          */
1139         function wasDeadlock() {
1140                 return $this->lastErrno() == 1213;
1141         }
1142
1143         /**
1144          * Determines if the last failure was due to a lock timeout
1145          *
1146          * @return bool
1147          */
1148         function wasLockTimeout() {
1149                 return $this->lastErrno() == 1205;
1150         }
1151
1152         function wasErrorReissuable() {
1153                 return $this->lastErrno() == 2013 || $this->lastErrno() == 2006;
1154         }
1155
1156         /**
1157          * Determines if the last failure was due to the database being read-only.
1158          *
1159          * @return bool
1160          */
1161         function wasReadOnlyError() {
1162                 return $this->lastErrno() == 1223 ||
1163                         ( $this->lastErrno() == 1290 && strpos( $this->lastError(), '--read-only' ) !== false );
1164         }
1165
1166         function wasConnectionError( $errno ) {
1167                 return $errno == 2013 || $errno == 2006;
1168         }
1169
1170         /**
1171          * Get the underlying binding handle, mConn
1172          *
1173          * Makes sure that mConn is set (disconnects and ping() failure can unset it).
1174          * This catches broken callers than catch and ignore disconnection exceptions.
1175          * Unlike checking isOpen(), this is safe to call inside of open().
1176          *
1177          * @return resource|object
1178          * @throws DBUnexpectedError
1179          * @since 1.26
1180          */
1181         protected function getBindingHandle() {
1182                 if ( !$this->mConn ) {
1183                         throw new DBUnexpectedError(
1184                                 $this,
1185                                 'DB connection was already closed or the connection dropped.'
1186                         );
1187                 }
1188
1189                 return $this->mConn;
1190         }
1191
1192         /**
1193          * @param string $oldName
1194          * @param string $newName
1195          * @param bool $temporary
1196          * @param string $fname
1197          * @return bool
1198          */
1199         function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = __METHOD__ ) {
1200                 $tmp = $temporary ? 'TEMPORARY ' : '';
1201                 $newName = $this->addIdentifierQuotes( $newName );
1202                 $oldName = $this->addIdentifierQuotes( $oldName );
1203                 $query = "CREATE $tmp TABLE $newName (LIKE $oldName)";
1204
1205                 return $this->query( $query, $fname );
1206         }
1207
1208         /**
1209          * List all tables on the database
1210          *
1211          * @param string $prefix Only show tables with this prefix, e.g. mw_
1212          * @param string $fname Calling function name
1213          * @return array
1214          */
1215         function listTables( $prefix = null, $fname = __METHOD__ ) {
1216                 $result = $this->query( "SHOW TABLES", $fname );
1217
1218                 $endArray = [];
1219
1220                 foreach ( $result as $table ) {
1221                         $vars = get_object_vars( $table );
1222                         $table = array_pop( $vars );
1223
1224                         if ( !$prefix || strpos( $table, $prefix ) === 0 ) {
1225                                 $endArray[] = $table;
1226                         }
1227                 }
1228
1229                 return $endArray;
1230         }
1231
1232         /**
1233          * @param string $tableName
1234          * @param string $fName
1235          * @return bool|ResultWrapper
1236          */
1237         public function dropTable( $tableName, $fName = __METHOD__ ) {
1238                 if ( !$this->tableExists( $tableName, $fName ) ) {
1239                         return false;
1240                 }
1241
1242                 return $this->query( "DROP TABLE IF EXISTS " . $this->tableName( $tableName ), $fName );
1243         }
1244
1245         /**
1246          * @return array
1247          */
1248         protected function getDefaultSchemaVars() {
1249                 $vars = parent::getDefaultSchemaVars();
1250                 $vars['wgDBTableOptions'] = str_replace( 'TYPE', 'ENGINE', $GLOBALS['wgDBTableOptions'] );
1251                 $vars['wgDBTableOptions'] = str_replace(
1252                         'CHARSET=mysql4',
1253                         'CHARSET=binary',
1254                         $vars['wgDBTableOptions']
1255                 );
1256
1257                 return $vars;
1258         }
1259
1260         /**
1261          * Get status information from SHOW STATUS in an associative array
1262          *
1263          * @param string $which
1264          * @return array
1265          */
1266         function getMysqlStatus( $which = "%" ) {
1267                 $res = $this->query( "SHOW STATUS LIKE '{$which}'" );
1268                 $status = [];
1269
1270                 foreach ( $res as $row ) {
1271                         $status[$row->Variable_name] = $row->Value;
1272                 }
1273
1274                 return $status;
1275         }
1276
1277         /**
1278          * Lists VIEWs in the database
1279          *
1280          * @param string $prefix Only show VIEWs with this prefix, eg.
1281          * unit_test_, or $wgDBprefix. Default: null, would return all views.
1282          * @param string $fname Name of calling function
1283          * @return array
1284          * @since 1.22
1285          */
1286         public function listViews( $prefix = null, $fname = __METHOD__ ) {
1287
1288                 if ( !isset( $this->allViews ) ) {
1289
1290                         // The name of the column containing the name of the VIEW
1291                         $propertyName = 'Tables_in_' . $this->mDBname;
1292
1293                         // Query for the VIEWS
1294                         $result = $this->query( 'SHOW FULL TABLES WHERE TABLE_TYPE = "VIEW"' );
1295                         $this->allViews = [];
1296                         while ( ( $row = $this->fetchRow( $result ) ) !== false ) {
1297                                 array_push( $this->allViews, $row[$propertyName] );
1298                         }
1299                 }
1300
1301                 if ( is_null( $prefix ) || $prefix === '' ) {
1302                         return $this->allViews;
1303                 }
1304
1305                 $filteredViews = [];
1306                 foreach ( $this->allViews as $viewName ) {
1307                         // Does the name of this VIEW start with the table-prefix?
1308                         if ( strpos( $viewName, $prefix ) === 0 ) {
1309                                 array_push( $filteredViews, $viewName );
1310                         }
1311                 }
1312
1313                 return $filteredViews;
1314         }
1315
1316         /**
1317          * Differentiates between a TABLE and a VIEW.
1318          *
1319          * @param string $name Name of the TABLE/VIEW to test
1320          * @param string $prefix
1321          * @return bool
1322          * @since 1.22
1323          */
1324         public function isView( $name, $prefix = null ) {
1325                 return in_array( $name, $this->listViews( $prefix ) );
1326         }
1327 }
1328
1329 /**
1330  * Utility class.
1331  * @ingroup Database
1332  */
1333 class MySQLField implements Field {
1334         private $name, $tablename, $default, $max_length, $nullable,
1335                 $is_pk, $is_unique, $is_multiple, $is_key, $type, $binary,
1336                 $is_numeric, $is_blob, $is_unsigned, $is_zerofill;
1337
1338         function __construct( $info ) {
1339                 $this->name = $info->name;
1340                 $this->tablename = $info->table;
1341                 $this->default = $info->def;
1342                 $this->max_length = $info->max_length;
1343                 $this->nullable = !$info->not_null;
1344                 $this->is_pk = $info->primary_key;
1345                 $this->is_unique = $info->unique_key;
1346                 $this->is_multiple = $info->multiple_key;
1347                 $this->is_key = ( $this->is_pk || $this->is_unique || $this->is_multiple );
1348                 $this->type = $info->type;
1349                 $this->binary = isset( $info->binary ) ? $info->binary : false;
1350                 $this->is_numeric = isset( $info->numeric ) ? $info->numeric : false;
1351                 $this->is_blob = isset( $info->blob ) ? $info->blob : false;
1352                 $this->is_unsigned = isset( $info->unsigned ) ? $info->unsigned : false;
1353                 $this->is_zerofill = isset( $info->zerofill ) ? $info->zerofill : false;
1354         }
1355
1356         /**
1357          * @return string
1358          */
1359         function name() {
1360                 return $this->name;
1361         }
1362
1363         /**
1364          * @return string
1365          */
1366         function tableName() {
1367                 return $this->tablename;
1368         }
1369
1370         /**
1371          * @return string
1372          */
1373         function type() {
1374                 return $this->type;
1375         }
1376
1377         /**
1378          * @return bool
1379          */
1380         function isNullable() {
1381                 return $this->nullable;
1382         }
1383
1384         function defaultValue() {
1385                 return $this->default;
1386         }
1387
1388         /**
1389          * @return bool
1390          */
1391         function isKey() {
1392                 return $this->is_key;
1393         }
1394
1395         /**
1396          * @return bool
1397          */
1398         function isMultipleKey() {
1399                 return $this->is_multiple;
1400         }
1401
1402         /**
1403          * @return bool
1404          */
1405         function isBinary() {
1406                 return $this->binary;
1407         }
1408
1409         /**
1410          * @return bool
1411          */
1412         function isNumeric() {
1413                 return $this->is_numeric;
1414         }
1415
1416         /**
1417          * @return bool
1418          */
1419         function isBlob() {
1420                 return $this->is_blob;
1421         }
1422
1423         /**
1424          * @return bool
1425          */
1426         function isUnsigned() {
1427                 return $this->is_unsigned;
1428         }
1429
1430         /**
1431          * @return bool
1432          */
1433         function isZerofill() {
1434                 return $this->is_zerofill;
1435         }
1436 }
1437
1438 /**
1439  * DBMasterPos class for MySQL/MariaDB
1440  *
1441  * Note that master positions and sync logic here make some assumptions:
1442  *  - Binlog-based usage assumes single-source replication and non-hierarchical replication.
1443  *  - GTID-based usage allows getting/syncing with multi-source replication. It is assumed
1444  *    that GTID sets are complete (e.g. include all domains on the server).
1445  */
1446 class MySQLMasterPos implements DBMasterPos {
1447         /** @var string Binlog file */
1448         public $file;
1449         /** @var int Binglog file position */
1450         public $pos;
1451         /** @var string[] GTID list */
1452         public $gtids = [];
1453         /** @var float UNIX timestamp */
1454         public $asOfTime = 0.0;
1455
1456         /**
1457          * @param string $file Binlog file name
1458          * @param integer $pos Binlog position
1459          * @param string $gtid Comma separated GTID set [optional]
1460          */
1461         function __construct( $file, $pos, $gtid = '' ) {
1462                 $this->file = $file;
1463                 $this->pos = $pos;
1464                 $this->gtids = array_map( 'trim', explode( ',', $gtid ) );
1465                 $this->asOfTime = microtime( true );
1466         }
1467
1468         /**
1469          * @return string <binlog file>/<position>, e.g db1034-bin.000976/843431247
1470          */
1471         function __toString() {
1472                 return "{$this->file}/{$this->pos}";
1473         }
1474
1475         function asOfTime() {
1476                 return $this->asOfTime;
1477         }
1478
1479         function hasReached( DBMasterPos $pos ) {
1480                 if ( !( $pos instanceof self ) ) {
1481                         throw new InvalidArgumentException( "Position not an instance of " . __CLASS__ );
1482                 }
1483
1484                 // Prefer GTID comparisons, which work with multi-tier replication
1485                 $thisPosByDomain = $this->getGtidCoordinates();
1486                 $thatPosByDomain = $pos->getGtidCoordinates();
1487                 if ( $thisPosByDomain && $thatPosByDomain ) {
1488                         $reached = true;
1489                         // Check that this has positions GTE all of those in $pos for all domains in $pos
1490                         foreach ( $thatPosByDomain as $domain => $thatPos ) {
1491                                 $thisPos = isset( $thisPosByDomain[$domain] ) ? $thisPosByDomain[$domain] : -1;
1492                                 $reached = $reached && ( $thatPos <= $thisPos );
1493                         }
1494
1495                         return $reached;
1496                 }
1497
1498                 // Fallback to the binlog file comparisons
1499                 $thisBinPos = $this->getBinlogCoordinates();
1500                 $thatBinPos = $pos->getBinlogCoordinates();
1501                 if ( $thisBinPos && $thatBinPos && $thisBinPos['binlog'] === $thatBinPos['binlog'] ) {
1502                         return ( $thisBinPos['pos'] >= $thatBinPos['pos'] );
1503                 }
1504
1505                 // Comparing totally different binlogs does not make sense
1506                 return false;
1507         }
1508
1509         function channelsMatch( DBMasterPos $pos ) {
1510                 if ( !( $pos instanceof self ) ) {
1511                         throw new InvalidArgumentException( "Position not an instance of " . __CLASS__ );
1512                 }
1513
1514                 // Prefer GTID comparisons, which work with multi-tier replication
1515                 $thisPosDomains = array_keys( $this->getGtidCoordinates() );
1516                 $thatPosDomains = array_keys( $pos->getGtidCoordinates() );
1517                 if ( $thisPosDomains && $thatPosDomains ) {
1518                         // Check that this has GTIDs for all domains in $pos
1519                         return !array_diff( $thatPosDomains, $thisPosDomains );
1520                 }
1521
1522                 // Fallback to the binlog file comparisons
1523                 $thisBinPos = $this->getBinlogCoordinates();
1524                 $thatBinPos = $pos->getBinlogCoordinates();
1525
1526                 return ( $thisBinPos && $thatBinPos && $thisBinPos['binlog'] === $thatBinPos['binlog'] );
1527         }
1528
1529         /**
1530          * @note: this returns false for multi-source replication GTID sets
1531          * @see https://mariadb.com/kb/en/mariadb/gtid
1532          * @see https://dev.mysql.com/doc/refman/5.6/en/replication-gtids-concepts.html
1533          * @return array Map of (domain => integer position) or false
1534          */
1535         protected function getGtidCoordinates() {
1536                 $gtidInfos = [];
1537                 foreach ( $this->gtids as $gtid ) {
1538                         $m = [];
1539                         // MariaDB style: <domain>-<server id>-<sequence number>
1540                         if ( preg_match( '!^(\d+)-\d+-(\d+)$!', $gtid, $m ) ) {
1541                                 $gtidInfos[(int)$m[1]] = (int)$m[2];
1542                         // MySQL style: <UUID domain>:<sequence number>
1543                         } elseif ( preg_match( '!^(\w{8}-\w{4}-\w{4}-\w{4}-\w{12}):(\d+)$!', $gtid, $m ) ) {
1544                                 $gtidInfos[$m[1]] = (int)$m[2];
1545                         } else {
1546                                 $gtidInfos = [];
1547                                 break; // unrecognized GTID
1548                         }
1549
1550                 }
1551
1552                 return $gtidInfos;
1553         }
1554
1555         /**
1556          * @see http://dev.mysql.com/doc/refman/5.7/en/show-master-status.html
1557          * @see http://dev.mysql.com/doc/refman/5.7/en/show-slave-status.html
1558          * @return array|bool (binlog, (integer file number, integer position)) or false
1559          */
1560         protected function getBinlogCoordinates() {
1561                 $m = [];
1562                 if ( preg_match( '!^(.+)\.(\d+)/(\d+)$!', (string)$this, $m ) ) {
1563                         return [ 'binlog' => $m[1], 'pos' => [ (int)$m[2], (int)$m[3] ] ];
1564                 }
1565
1566                 return false;
1567         }
1568 }