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 reconnect() {
 603                 $this->closeConnection();
 604                 $this->mOpened = false;
 605                 $this->mConn = false;
 606                 $this->open( $this->mServer, $this->mUser, $this->mPassword, $this->mDBname );
 607
 608                 return true;
 609         }
 610
 611         function getLag() {
 612                 if ( $this->getLagDetectionMethod() === 'pt-heartbeat' ) {
 613                         return $this->getLagFromPtHeartbeat();
 614                 } else {
 615                         return $this->getLagFromSlaveStatus();
 616                 }
 617         }
 618
 619         /**
 620          * @return string
 621          */
 622         protected function getLagDetectionMethod() {
 623                 return $this->lagDetectionMethod;
 624         }
 625
 626         /**
 627          * @return bool|int
 628          */
 629         protected function getLagFromSlaveStatus() {
 630                 $res = $this->query( 'SHOW SLAVE STATUS', __METHOD__ );
 631                 $row = $res ? $res->fetchObject() : false;
 632                 if ( $row && strval( $row->Seconds_Behind_Master ) !== '' ) {
 633                         return intval( $row->Seconds_Behind_Master );
 634                 }
 635
 636                 return false;
 637         }
 638
 639         /**
 640          * @return bool|float
 641          */
 642         protected function getLagFromPtHeartbeat() {
 643                 $options = $this->lagDetectionOptions;
 644
 645                 if ( isset( $options['conds'] ) ) {
 646                         // Best method for multi-DC setups: use logical channel names
 647                         $data = $this->getHeartbeatData( $options['conds'] );
 648                 } else {
 649                         // Standard method: use master server ID (works with stock pt-heartbeat)
 650                         $masterInfo = $this->getMasterServerInfo();
 651                         if ( !$masterInfo ) {
 652                                 wfLogDBError(
 653                                         "Unable to query master of {db_server} for server ID",
 654                                         $this->getLogContext( [
 655                                                 'method' => __METHOD__
 656                                         ] )
 657                                 );
 658
 659                                 return false; // could not get master server ID
 660                         }
 661
 662                         $conds = [ 'server_id' => intval( $masterInfo['serverId'] ) ];
 663                         $data = $this->getHeartbeatData( $conds );
 664                 }
 665
 666                 list( $time, $nowUnix ) = $data;
 667                 if ( $time !== null ) {
 668                         // @time is in ISO format like "2015-09-25T16:48:10.000510"
 669                         $dateTime = new DateTime( $time, new DateTimeZone( 'UTC' ) );
 670                         $timeUnix = (int)$dateTime->format( 'U' ) + $dateTime->format( 'u' ) / 1e6;
 671
 672                         return max( $nowUnix - $timeUnix, 0.0 );
 673                 }
 674
 675                 wfLogDBError(
 676                         "Unable to find pt-heartbeat row for {db_server}",
 677                         $this->getLogContext( [
 678                                 'method' => __METHOD__
 679                         ] )
 680                 );
 681
 682                 return false;
 683         }
 684
 685         protected function getMasterServerInfo() {
 686                 $cache = $this->srvCache;
 687                 $key = $cache->makeGlobalKey(
 688                         'mysql',
 689                         'master-info',
 690                         // Using one key for all cluster slaves is preferable
 691                         $this->getLBInfo( 'clusterMasterHost' ) ?: $this->getServer()
 692                 );
 693
 694                 return $cache->getWithSetCallback(
 695                         $key,
 696                         $cache::TTL_INDEFINITE,
 697                         function () use ( $cache, $key ) {
 698                                 // Get and leave a lock key in place for a short period
 699                                 if ( !$cache->lock( $key, 0, 10 ) ) {
 700                                         return false; // avoid master connection spike slams
 701                                 }
 702
 703                                 $conn = $this->getLazyMasterHandle();
 704                                 if ( !$conn ) {
 705                                         return false; // something is misconfigured
 706                                 }
 707
 708                                 // Connect to and query the master; catch errors to avoid outages
 709                                 try {
 710                                         $res = $conn->query( 'SELECT @@server_id AS id', __METHOD__ );
 711                                         $row = $res ? $res->fetchObject() : false;
 712                                         $id = $row ? (int)$row->id : 0;
 713                                 } catch ( DBError $e ) {
 714                                         $id = 0;
 715                                 }
 716
 717                                 // Cache the ID if it was retrieved
 718                                 return $id ? [ 'serverId' => $id, 'asOf' => time() ] : false;
 719                         }
 720                 );
 721         }
 722
 723         /**
 724          * @param array $conds WHERE clause conditions to find a row
 725          * @return array (heartbeat `ts` column value or null, UNIX timestamp) for the newest beat
 726          * @see https://www.percona.com/doc/percona-toolkit/2.1/pt-heartbeat.html
 727          */
 728         protected function getHeartbeatData( array $conds ) {
 729                 $whereSQL = $this->makeList( $conds, LIST_AND );
 730                 // Use ORDER BY for channel based queries since that field might not be UNIQUE.
 731                 // Note: this would use "TIMESTAMPDIFF(MICROSECOND,ts,UTC_TIMESTAMP(6))" but the
 732                 // percision field is not supported in MySQL <= 5.5.
 733                 $res = $this->query(
 734                         "SELECT ts FROM heartbeat.heartbeat WHERE $whereSQL ORDER BY ts DESC LIMIT 1"
 735                 );
 736                 $row = $res ? $res->fetchObject() : false;
 737
 738                 return [ $row ? $row->ts : null, microtime( true ) ];
 739         }
 740
 741         public function getApproximateLagStatus() {
 742                 if ( $this->getLagDetectionMethod() === 'pt-heartbeat' ) {
 743                         // Disable caching since this is fast enough and we don't wan't
 744                         // to be *too* pessimistic by having both the cache TTL and the
 745                         // pt-heartbeat interval count as lag in getSessionLagStatus()
 746                         return parent::getApproximateLagStatus();
 747                 }
 748
 749                 $key = $this->srvCache->makeGlobalKey( 'mysql-lag', $this->getServer() );
 750                 $approxLag = $this->srvCache->get( $key );
 751                 if ( !$approxLag ) {
 752                         $approxLag = parent::getApproximateLagStatus();
 753                         $this->srvCache->set( $key, $approxLag, 1 );
 754                 }
 755
 756                 return $approxLag;
 757         }
 758
 759         function masterPosWait( DBMasterPos $pos, $timeout ) {
 760                 if ( !( $pos instanceof MySQLMasterPos ) ) {
 761                         throw new InvalidArgumentException( "Position not an instance of MySQLMasterPos" );
 762                 }
 763
 764                 if ( $this->getLBInfo( 'is static' ) === true ) {
 765                         return 0; // this is a copy of a read-only dataset with no master DB
 766                 } elseif ( $this->lastKnownSlavePos && $this->lastKnownSlavePos->hasReached( $pos ) ) {
 767                         return 0; // already reached this point for sure
 768                 }
 769
 770                 // Commit any open transactions
 771                 $this->commit( __METHOD__, 'flush' );
 772
 773                 // Call doQuery() directly, to avoid opening a transaction if DBO_TRX is set
 774                 if ( $this->useGTIDs && $pos->gtids ) {
 775                         // Wait on the GTID set (MariaDB only)
 776                         $gtidArg = $this->addQuotes( implode( ',', $pos->gtids ) );
 777                         $res = $this->doQuery( "SELECT MASTER_GTID_WAIT($gtidArg, $timeout)" );
 778                 } else {
 779                         // Wait on the binlog coordinates
 780                         $encFile = $this->addQuotes( $pos->file );
 781                         $encPos = intval( $pos->pos );
 782                         $res = $this->doQuery( "SELECT MASTER_POS_WAIT($encFile, $encPos, $timeout)" );
 783                 }
 784
 785                 $row = $res ? $this->fetchRow( $res ) : false;
 786                 if ( !$row ) {
 787                         throw new DBExpectedError( $this, "Failed to query MASTER_POS_WAIT()" );
 788                 }
 789
 790                 // Result can be NULL (error), -1 (timeout), or 0+ per the MySQL manual
 791                 $status = ( $row[0] !== null ) ? intval( $row[0] ) : null;
 792                 if ( $status === null ) {
 793                         // T126436: jobs programmed to wait on master positions might be referencing binlogs
 794                         // with an old master hostname. Such calls make MASTER_POS_WAIT() return null. Try
 795                         // to detect this and treat the slave as having reached the position; a proper master
 796                         // switchover already requires that the new master be caught up before the switch.
 797                         $slavePos = $this->getSlavePos();
 798                         if ( $slavePos && !$slavePos->channelsMatch( $pos ) ) {
 799                                 $this->lastKnownSlavePos = $slavePos;
 800                                 $status = 0;
 801                         }
 802                 } elseif ( $status >= 0 ) {
 803                         // Remember that this position was reached to save queries next time
 804                         $this->lastKnownSlavePos = $pos;
 805                 }
 806
 807                 return $status;
 808         }
 809
 810         /**
 811          * Get the position of the master from SHOW SLAVE STATUS
 812          *
 813          * @return MySQLMasterPos|bool
 814          */
 815         function getSlavePos() {
 816                 $res = $this->query( 'SHOW SLAVE STATUS', __METHOD__ );
 817                 $row = $this->fetchObject( $res );
 818
 819                 if ( $row ) {
 820                         $pos = isset( $row->Exec_master_log_pos )
 821                                 ? $row->Exec_master_log_pos
 822                                 : $row->Exec_Master_Log_Pos;
 823                         // Also fetch the last-applied GTID set (MariaDB)
 824                         if ( $this->useGTIDs ) {
 825                                 $res = $this->query( "SHOW GLOBAL VARIABLES LIKE 'gtid_slave_pos'", __METHOD__ );
 826                                 $gtidRow = $this->fetchObject( $res );
 827                                 $gtidSet = $gtidRow ? $gtidRow->Value : '';
 828                         } else {
 829                                 $gtidSet = '';
 830                         }
 831
 832                         return new MySQLMasterPos( $row->Relay_Master_Log_File, $pos, $gtidSet );
 833                 } else {
 834                         return false;
 835                 }
 836         }
 837
 838         /**
 839          * Get the position of the master from SHOW MASTER STATUS
 840          *
 841          * @return MySQLMasterPos|bool
 842          */
 843         function getMasterPos() {
 844                 $res = $this->query( 'SHOW MASTER STATUS', __METHOD__ );
 845                 $row = $this->fetchObject( $res );
 846
 847                 if ( $row ) {
 848                         // Also fetch the last-written GTID set (MariaDB)
 849                         if ( $this->useGTIDs ) {
 850                                 $res = $this->query( "SHOW GLOBAL VARIABLES LIKE 'gtid_binlog_pos'", __METHOD__ );
 851                                 $gtidRow = $this->fetchObject( $res );
 852                                 $gtidSet = $gtidRow ? $gtidRow->Value : '';
 853                         } else {
 854                                 $gtidSet = '';
 855                         }
 856
 857                         return new MySQLMasterPos( $row->File, $row->Position, $gtidSet );
 858                 } else {
 859                         return false;
 860                 }
 861         }
 862
 863         public function serverIsReadOnly() {
 864                 $res = $this->query( "SHOW GLOBAL VARIABLES LIKE 'read_only'", __METHOD__ );
 865                 $row = $this->fetchObject( $res );
 866
 867                 return $row ? ( strtolower( $row->Value ) === 'on' ) : false;
 868         }
 869
 870         /**
 871          * @param string $index
 872          * @return string
 873          */
 874         function useIndexClause( $index ) {
 875                 return "FORCE INDEX (" . $this->indexName( $index ) . ")";
 876         }
 877
 878         /**
 879          * @return string
 880          */
 881         function lowPriorityOption() {
 882                 return 'LOW_PRIORITY';
 883         }
 884
 885         /**
 886          * @return string
 887          */
 888         public function getSoftwareLink() {
 889                 // MariaDB includes its name in its version string; this is how MariaDB's version of
 890                 // the mysql command-line client identifies MariaDB servers (see mariadb_connection()
 891                 // in libmysql/libmysql.c).
 892                 $version = $this->getServerVersion();
 893                 if ( strpos( $version, 'MariaDB' ) !== false || strpos( $version, '-maria-' ) !== false ) {
 894                         return '[{{int:version-db-mariadb-url}} MariaDB]';
 895                 }
 896
 897                 // Percona Server's version suffix is not very distinctive, and @@version_comment
 898                 // doesn't give the necessary info for source builds, so assume the server is MySQL.
 899                 // (Even Percona's version of mysql doesn't try to make the distinction.)
 900                 return '[{{int:version-db-mysql-url}} MySQL]';
 901         }
 902
 903         /**
 904          * @return string
 905          */
 906         public function getServerVersion() {
 907                 // Not using mysql_get_server_info() or similar for consistency: in the handshake,
 908                 // MariaDB 10 adds the prefix "5.5.5-", and only some newer client libraries strip
 909                 // it off (see RPL_VERSION_HACK in include/mysql_com.h).
 910                 if ( $this->serverVersion === null ) {
 911                         $this->serverVersion = $this->selectField( '', 'VERSION()', '', __METHOD__ );
 912                 }
 913                 return $this->serverVersion;
 914         }
 915
 916         /**
 917          * @param array $options
 918          */
 919         public function setSessionOptions( array $options ) {
 920                 if ( isset( $options['connTimeout'] ) ) {
 921                         $timeout = (int)$options['connTimeout'];
 922                         $this->query( "SET net_read_timeout=$timeout" );
 923                         $this->query( "SET net_write_timeout=$timeout" );
 924                 }
 925         }
 926
 927         /**
 928          * @param string $sql
 929          * @param string $newLine
 930          * @return bool
 931          */
 932         public function streamStatementEnd( &$sql, &$newLine ) {
 933                 if ( strtoupper( substr( $newLine, 0, 9 ) ) == 'DELIMITER' ) {
 934                         preg_match( '/^DELIMITER\s+(\S+)/', $newLine, $m );
 935                         $this->delimiter = $m[1];
 936                         $newLine = '';
 937                 }
 938
 939                 return parent::streamStatementEnd( $sql, $newLine );
 940         }
 941
 942         /**
 943          * Check to see if a named lock is available. This is non-blocking.
 944          *
 945          * @param string $lockName Name of lock to poll
 946          * @param string $method Name of method calling us
 947          * @return bool
 948          * @since 1.20
 949          */
 950         public function lockIsFree( $lockName, $method ) {
 951                 $lockName = $this->addQuotes( $this->makeLockName( $lockName ) );
 952                 $result = $this->query( "SELECT IS_FREE_LOCK($lockName) AS lockstatus", $method );
 953                 $row = $this->fetchObject( $result );
 954
 955                 return ( $row->lockstatus == 1 );
 956         }
 957
 958         /**
 959          * @param string $lockName
 960          * @param string $method
 961          * @param int $timeout
 962          * @return bool
 963          */
 964         public function lock( $lockName, $method, $timeout = 5 ) {
 965                 $lockName = $this->addQuotes( $this->makeLockName( $lockName ) );
 966                 $result = $this->query( "SELECT GET_LOCK($lockName, $timeout) AS lockstatus", $method );
 967                 $row = $this->fetchObject( $result );
 968
 969                 if ( $row->lockstatus == 1 ) {
 970                         parent::lock( $lockName, $method, $timeout ); // record
 971                         return true;
 972                 }
 973
 974                 wfDebug( __METHOD__ . " failed to acquire lock\n" );
 975
 976                 return false;
 977         }
 978
 979         /**
 980          * FROM MYSQL DOCS:
 981          * http://dev.mysql.com/doc/refman/5.0/en/miscellaneous-functions.html#function_release-lock
 982          * @param string $lockName
 983          * @param string $method
 984          * @return bool
 985          */
 986         public function unlock( $lockName, $method ) {
 987                 $lockName = $this->addQuotes( $this->makeLockName( $lockName ) );
 988                 $result = $this->query( "SELECT RELEASE_LOCK($lockName) as lockstatus", $method );
 989                 $row = $this->fetchObject( $result );
 990
 991                 if ( $row->lockstatus == 1 ) {
 992                         parent::unlock( $lockName, $method ); // record
 993                         return true;
 994                 }
 995
 996                 wfDebug( __METHOD__ . " failed to release lock\n" );
 997
 998                 return false;
 999         }
1000
1001         private function makeLockName( $lockName ) {
1002                 // http://dev.mysql.com/doc/refman/5.7/en/miscellaneous-functions.html#function_get-lock
1003                 // Newer version enforce a 64 char length limit.
1004                 return ( strlen( $lockName ) > 64 ) ? sha1( $lockName ) : $lockName;
1005         }
1006
1007         public function namedLocksEnqueue() {
1008                 return true;
1009         }
1010
1011         /**
1012          * @param array $read
1013          * @param array $write
1014          * @param string $method
1015          * @param bool $lowPriority
1016          * @return bool
1017          */
1018         public function lockTables( $read, $write, $method, $lowPriority = true ) {
1019                 $items = [];
1020
1021                 foreach ( $write as $table ) {
1022                         $tbl = $this->tableName( $table ) .
1023                                 ( $lowPriority ? ' LOW_PRIORITY' : '' ) .
1024                                 ' WRITE';
1025                         $items[] = $tbl;
1026                 }
1027                 foreach ( $read as $table ) {
1028                         $items[] = $this->tableName( $table ) . ' READ';
1029                 }
1030                 $sql = "LOCK TABLES " . implode( ',', $items );
1031                 $this->query( $sql, $method );
1032
1033                 return true;
1034         }
1035
1036         /**
1037          * @param string $method
1038          * @return bool
1039          */
1040         public function unlockTables( $method ) {
1041                 $this->query( "UNLOCK TABLES", $method );
1042
1043                 return true;
1044         }
1045
1046         /**
1047          * Get search engine class. All subclasses of this
1048          * need to implement this if they wish to use searching.
1049          *
1050          * @return string
1051          */
1052         public function getSearchEngine() {
1053                 return 'SearchMySQL';
1054         }
1055
1056         /**
1057          * @param bool $value
1058          */
1059         public function setBigSelects( $value = true ) {
1060                 if ( $value === 'default' ) {
1061                         if ( $this->mDefaultBigSelects === null ) {
1062                                 # Function hasn't been called before so it must already be set to the default
1063                                 return;
1064                         } else {
1065                                 $value = $this->mDefaultBigSelects;
1066                         }
1067                 } elseif ( $this->mDefaultBigSelects === null ) {
1068                         $this->mDefaultBigSelects =
1069                                 (bool)$this->selectField( false, '@@sql_big_selects', '', __METHOD__ );
1070                 }
1071                 $encValue = $value ? '1' : '0';
1072                 $this->query( "SET sql_big_selects=$encValue", __METHOD__ );
1073         }
1074
1075         /**
1076          * DELETE where the condition is a join. MySql uses multi-table deletes.
1077          * @param string $delTable
1078          * @param string $joinTable
1079          * @param string $delVar
1080          * @param string $joinVar
1081          * @param array|string $conds
1082          * @param bool|string $fname
1083          * @throws DBUnexpectedError
1084          * @return bool|ResultWrapper
1085          */
1086         function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = __METHOD__ ) {
1087                 if ( !$conds ) {
1088                         throw new DBUnexpectedError( $this, 'DatabaseBase::deleteJoin() called with empty $conds' );
1089                 }
1090
1091                 $delTable = $this->tableName( $delTable );
1092                 $joinTable = $this->tableName( $joinTable );
1093                 $sql = "DELETE $delTable FROM $delTable, $joinTable WHERE $delVar=$joinVar ";
1094
1095                 if ( $conds != '*' ) {
1096                         $sql .= ' AND ' . $this->makeList( $conds, LIST_AND );
1097                 }
1098
1099                 return $this->query( $sql, $fname );
1100         }
1101
1102         /**
1103          * @param string $table
1104          * @param array $rows
1105          * @param array $uniqueIndexes
1106          * @param array $set
1107          * @param string $fname
1108          * @return bool
1109          */
1110         public function upsert( $table, array $rows, array $uniqueIndexes,
1111                 array $set, $fname = __METHOD__
1112         ) {
1113                 if ( !count( $rows ) ) {
1114                         return true; // nothing to do
1115                 }
1116
1117                 if ( !is_array( reset( $rows ) ) ) {
1118                         $rows = [ $rows ];
1119                 }
1120
1121                 $table = $this->tableName( $table );
1122                 $columns = array_keys( $rows[0] );
1123
1124                 $sql = "INSERT INTO $table (" . implode( ',', $columns ) . ') VALUES ';
1125                 $rowTuples = [];
1126                 foreach ( $rows as $row ) {
1127                         $rowTuples[] = '(' . $this->makeList( $row ) . ')';
1128                 }
1129                 $sql .= implode( ',', $rowTuples );
1130                 $sql .= " ON DUPLICATE KEY UPDATE " . $this->makeList( $set, LIST_SET );
1131
1132                 return (bool)$this->query( $sql, $fname );
1133         }
1134
1135         /**
1136          * Determines how long the server has been up
1137          *
1138          * @return int
1139          */
1140         function getServerUptime() {
1141                 $vars = $this->getMysqlStatus( 'Uptime' );
1142
1143                 return (int)$vars['Uptime'];
1144         }
1145
1146         /**
1147          * Determines if the last failure was due to a deadlock
1148          *
1149          * @return bool
1150          */
1151         function wasDeadlock() {
1152                 return $this->lastErrno() == 1213;
1153         }
1154
1155         /**
1156          * Determines if the last failure was due to a lock timeout
1157          *
1158          * @return bool
1159          */
1160         function wasLockTimeout() {
1161                 return $this->lastErrno() == 1205;
1162         }
1163
1164         function wasErrorReissuable() {
1165                 return $this->lastErrno() == 2013 || $this->lastErrno() == 2006;
1166         }
1167
1168         /**
1169          * Determines if the last failure was due to the database being read-only.
1170          *
1171          * @return bool
1172          */
1173         function wasReadOnlyError() {
1174                 return $this->lastErrno() == 1223 ||
1175                         ( $this->lastErrno() == 1290 && strpos( $this->lastError(), '--read-only' ) !== false );
1176         }
1177
1178         function wasConnectionError( $errno ) {
1179                 return $errno == 2013 || $errno == 2006;
1180         }
1181
1182         /**
1183          * Get the underlying binding handle, mConn
1184          *
1185          * Makes sure that mConn is set (disconnects and ping() failure can unset it).
1186          * This catches broken callers than catch and ignore disconnection exceptions.
1187          * Unlike checking isOpen(), this is safe to call inside of open().
1188          *
1189          * @return resource|object
1190          * @throws DBUnexpectedError
1191          * @since 1.26
1192          */
1193         protected function getBindingHandle() {
1194                 if ( !$this->mConn ) {
1195                         throw new DBUnexpectedError(
1196                                 $this,
1197                                 'DB connection was already closed or the connection dropped.'
1198                         );
1199                 }
1200
1201                 return $this->mConn;
1202         }
1203
1204         /**
1205          * @param string $oldName
1206          * @param string $newName
1207          * @param bool $temporary
1208          * @param string $fname
1209          * @return bool
1210          */
1211         function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = __METHOD__ ) {
1212                 $tmp = $temporary ? 'TEMPORARY ' : '';
1213                 $newName = $this->addIdentifierQuotes( $newName );
1214                 $oldName = $this->addIdentifierQuotes( $oldName );
1215                 $query = "CREATE $tmp TABLE $newName (LIKE $oldName)";
1216
1217                 return $this->query( $query, $fname );
1218         }
1219
1220         /**
1221          * List all tables on the database
1222          *
1223          * @param string $prefix Only show tables with this prefix, e.g. mw_
1224          * @param string $fname Calling function name
1225          * @return array
1226          */
1227         function listTables( $prefix = null, $fname = __METHOD__ ) {
1228                 $result = $this->query( "SHOW TABLES", $fname );
1229
1230                 $endArray = [];
1231
1232                 foreach ( $result as $table ) {
1233                         $vars = get_object_vars( $table );
1234                         $table = array_pop( $vars );
1235
1236                         if ( !$prefix || strpos( $table, $prefix ) === 0 ) {
1237                                 $endArray[] = $table;
1238                         }
1239                 }
1240
1241                 return $endArray;
1242         }
1243
1244         /**
1245          * @param string $tableName
1246          * @param string $fName
1247          * @return bool|ResultWrapper
1248          */
1249         public function dropTable( $tableName, $fName = __METHOD__ ) {
1250                 if ( !$this->tableExists( $tableName, $fName ) ) {
1251                         return false;
1252                 }
1253
1254                 return $this->query( "DROP TABLE IF EXISTS " . $this->tableName( $tableName ), $fName );
1255         }
1256
1257         /**
1258          * @return array
1259          */
1260         protected function getDefaultSchemaVars() {
1261                 $vars = parent::getDefaultSchemaVars();
1262                 $vars['wgDBTableOptions'] = str_replace( 'TYPE', 'ENGINE', $GLOBALS['wgDBTableOptions'] );
1263                 $vars['wgDBTableOptions'] = str_replace(
1264                         'CHARSET=mysql4',
1265                         'CHARSET=binary',
1266                         $vars['wgDBTableOptions']
1267                 );
1268
1269                 return $vars;
1270         }
1271
1272         /**
1273          * Get status information from SHOW STATUS in an associative array
1274          *
1275          * @param string $which
1276          * @return array
1277          */
1278         function getMysqlStatus( $which = "%" ) {
1279                 $res = $this->query( "SHOW STATUS LIKE '{$which}'" );
1280                 $status = [];
1281
1282                 foreach ( $res as $row ) {
1283                         $status[$row->Variable_name] = $row->Value;
1284                 }
1285
1286                 return $status;
1287         }
1288
1289         /**
1290          * Lists VIEWs in the database
1291          *
1292          * @param string $prefix Only show VIEWs with this prefix, eg.
1293          * unit_test_, or $wgDBprefix. Default: null, would return all views.
1294          * @param string $fname Name of calling function
1295          * @return array
1296          * @since 1.22
1297          */
1298         public function listViews( $prefix = null, $fname = __METHOD__ ) {
1299
1300                 if ( !isset( $this->allViews ) ) {
1301
1302                         // The name of the column containing the name of the VIEW
1303                         $propertyName = 'Tables_in_' . $this->mDBname;
1304
1305                         // Query for the VIEWS
1306                         $result = $this->query( 'SHOW FULL TABLES WHERE TABLE_TYPE = "VIEW"' );
1307                         $this->allViews = [];
1308                         while ( ( $row = $this->fetchRow( $result ) ) !== false ) {
1309                                 array_push( $this->allViews, $row[$propertyName] );
1310                         }
1311                 }
1312
1313                 if ( is_null( $prefix ) || $prefix === '' ) {
1314                         return $this->allViews;
1315                 }
1316
1317                 $filteredViews = [];
1318                 foreach ( $this->allViews as $viewName ) {
1319                         // Does the name of this VIEW start with the table-prefix?
1320                         if ( strpos( $viewName, $prefix ) === 0 ) {
1321                                 array_push( $filteredViews, $viewName );
1322                         }
1323                 }
1324
1325                 return $filteredViews;
1326         }
1327
1328         /**
1329          * Differentiates between a TABLE and a VIEW.
1330          *
1331          * @param string $name Name of the TABLE/VIEW to test
1332          * @param string $prefix
1333          * @return bool
1334          * @since 1.22
1335          */
1336         public function isView( $name, $prefix = null ) {
1337                 return in_array( $name, $this->listViews( $prefix ) );
1338         }
1339 }
1340
1341 /**
1342  * Utility class.
1343  * @ingroup Database
1344  */
1345 class MySQLField implements Field {
1346         private $name, $tablename, $default, $max_length, $nullable,
1347                 $is_pk, $is_unique, $is_multiple, $is_key, $type, $binary,
1348                 $is_numeric, $is_blob, $is_unsigned, $is_zerofill;
1349
1350         function __construct( $info ) {
1351                 $this->name = $info->name;
1352                 $this->tablename = $info->table;
1353                 $this->default = $info->def;
1354                 $this->max_length = $info->max_length;
1355                 $this->nullable = !$info->not_null;
1356                 $this->is_pk = $info->primary_key;
1357                 $this->is_unique = $info->unique_key;
1358                 $this->is_multiple = $info->multiple_key;
1359                 $this->is_key = ( $this->is_pk || $this->is_unique || $this->is_multiple );
1360                 $this->type = $info->type;
1361                 $this->binary = isset( $info->binary ) ? $info->binary : false;
1362                 $this->is_numeric = isset( $info->numeric ) ? $info->numeric : false;
1363                 $this->is_blob = isset( $info->blob ) ? $info->blob : false;
1364                 $this->is_unsigned = isset( $info->unsigned ) ? $info->unsigned : false;
1365                 $this->is_zerofill = isset( $info->zerofill ) ? $info->zerofill : false;
1366         }
1367
1368         /**
1369          * @return string
1370          */
1371         function name() {
1372                 return $this->name;
1373         }
1374
1375         /**
1376          * @return string
1377          */
1378         function tableName() {
1379                 return $this->tablename;
1380         }
1381
1382         /**
1383          * @return string
1384          */
1385         function type() {
1386                 return $this->type;
1387         }
1388
1389         /**
1390          * @return bool
1391          */
1392         function isNullable() {
1393                 return $this->nullable;
1394         }
1395
1396         function defaultValue() {
1397                 return $this->default;
1398         }
1399
1400         /**
1401          * @return bool
1402          */
1403         function isKey() {
1404                 return $this->is_key;
1405         }
1406
1407         /**
1408          * @return bool
1409          */
1410         function isMultipleKey() {
1411                 return $this->is_multiple;
1412         }
1413
1414         /**
1415          * @return bool
1416          */
1417         function isBinary() {
1418                 return $this->binary;
1419         }
1420
1421         /**
1422          * @return bool
1423          */
1424         function isNumeric() {
1425                 return $this->is_numeric;
1426         }
1427
1428         /**
1429          * @return bool
1430          */
1431         function isBlob() {
1432                 return $this->is_blob;
1433         }
1434
1435         /**
1436          * @return bool
1437          */
1438         function isUnsigned() {
1439                 return $this->is_unsigned;
1440         }
1441
1442         /**
1443          * @return bool
1444          */
1445         function isZerofill() {
1446                 return $this->is_zerofill;
1447         }
1448 }
1449
1450 /**
1451  * DBMasterPos class for MySQL/MariaDB
1452  *
1453  * Note that master positions and sync logic here make some assumptions:
1454  *  - Binlog-based usage assumes single-source replication and non-hierarchical replication.
1455  *  - GTID-based usage allows getting/syncing with multi-source replication. It is assumed
1456  *    that GTID sets are complete (e.g. include all domains on the server).
1457  */
1458 class MySQLMasterPos implements DBMasterPos {
1459         /** @var string Binlog file */
1460         public $file;
1461         /** @var int Binglog file position */
1462         public $pos;
1463         /** @var string[] GTID list */
1464         public $gtids = [];
1465         /** @var float UNIX timestamp */
1466         public $asOfTime = 0.0;
1467
1468         /**
1469          * @param string $file Binlog file name
1470          * @param integer $pos Binlog position
1471          * @param string $gtid Comma separated GTID set [optional]
1472          */
1473         function __construct( $file, $pos, $gtid = '' ) {
1474                 $this->file = $file;
1475                 $this->pos = $pos;
1476                 $this->gtids = array_map( 'trim', explode( ',', $gtid ) );
1477                 $this->asOfTime = microtime( true );
1478         }
1479
1480         /**
1481          * @return string <binlog file>/<position>, e.g db1034-bin.000976/843431247
1482          */
1483         function __toString() {
1484                 return "{$this->file}/{$this->pos}";
1485         }
1486
1487         function asOfTime() {
1488                 return $this->asOfTime;
1489         }
1490
1491         function hasReached( DBMasterPos $pos ) {
1492                 if ( !( $pos instanceof self ) ) {
1493                         throw new InvalidArgumentException( "Position not an instance of " . __CLASS__ );
1494                 }
1495
1496                 // Prefer GTID comparisons, which work with multi-tier replication
1497                 $thisPosByDomain = $this->getGtidCoordinates();
1498                 $thatPosByDomain = $pos->getGtidCoordinates();
1499                 if ( $thisPosByDomain && $thatPosByDomain ) {
1500                         $reached = true;
1501                         // Check that this has positions GTE all of those in $pos for all domains in $pos
1502                         foreach ( $thatPosByDomain as $domain => $thatPos ) {
1503                                 $thisPos = isset( $thisPosByDomain[$domain] ) ? $thisPosByDomain[$domain] : -1;
1504                                 $reached = $reached && ( $thatPos <= $thisPos );
1505                         }
1506
1507                         return $reached;
1508                 }
1509
1510                 // Fallback to the binlog file comparisons
1511                 $thisBinPos = $this->getBinlogCoordinates();
1512                 $thatBinPos = $pos->getBinlogCoordinates();
1513                 if ( $thisBinPos && $thatBinPos && $thisBinPos['binlog'] === $thatBinPos['binlog'] ) {
1514                         return ( $thisBinPos['pos'] >= $thatBinPos['pos'] );
1515                 }
1516
1517                 // Comparing totally different binlogs does not make sense
1518                 return false;
1519         }
1520
1521         function channelsMatch( DBMasterPos $pos ) {
1522                 if ( !( $pos instanceof self ) ) {
1523                         throw new InvalidArgumentException( "Position not an instance of " . __CLASS__ );
1524                 }
1525
1526                 // Prefer GTID comparisons, which work with multi-tier replication
1527                 $thisPosDomains = array_keys( $this->getGtidCoordinates() );
1528                 $thatPosDomains = array_keys( $pos->getGtidCoordinates() );
1529                 if ( $thisPosDomains && $thatPosDomains ) {
1530                         // Check that this has GTIDs for all domains in $pos
1531                         return !array_diff( $thatPosDomains, $thisPosDomains );
1532                 }
1533
1534                 // Fallback to the binlog file comparisons
1535                 $thisBinPos = $this->getBinlogCoordinates();
1536                 $thatBinPos = $pos->getBinlogCoordinates();
1537
1538                 return ( $thisBinPos && $thatBinPos && $thisBinPos['binlog'] === $thatBinPos['binlog'] );
1539         }
1540
1541         /**
1542          * @note: this returns false for multi-source replication GTID sets
1543          * @see https://mariadb.com/kb/en/mariadb/gtid
1544          * @see https://dev.mysql.com/doc/refman/5.6/en/replication-gtids-concepts.html
1545          * @return array Map of (domain => integer position) or false
1546          */
1547         protected function getGtidCoordinates() {
1548                 $gtidInfos = [];
1549                 foreach ( $this->gtids as $gtid ) {
1550                         $m = [];
1551                         // MariaDB style: <domain>-<server id>-<sequence number>
1552                         if ( preg_match( '!^(\d+)-\d+-(\d+)$!', $gtid, $m ) ) {
1553                                 $gtidInfos[(int)$m[1]] = (int)$m[2];
1554                         // MySQL style: <UUID domain>:<sequence number>
1555                         } elseif ( preg_match( '!^(\w{8}-\w{4}-\w{4}-\w{4}-\w{12}):(\d+)$!', $gtid, $m ) ) {
1556                                 $gtidInfos[$m[1]] = (int)$m[2];
1557                         } else {
1558                                 $gtidInfos = [];
1559                                 break; // unrecognized GTID
1560                         }
1561
1562                 }
1563
1564                 return $gtidInfos;
1565         }
1566
1567         /**
1568          * @see http://dev.mysql.com/doc/refman/5.7/en/show-master-status.html
1569          * @see http://dev.mysql.com/doc/refman/5.7/en/show-slave-status.html
1570          * @return array|bool (binlog, (integer file number, integer position)) or false
1571          */
1572         protected function getBinlogCoordinates() {
1573                 $m = [];
1574                 if ( preg_match( '!^(.+)\.(\d+)/(\d+)$!', (string)$this, $m ) ) {
1575                         return [ 'binlog' => $m[1], 'pos' => [ (int)$m[2], (int)$m[3] ] ];
1576                 }
1577
1578                 return false;
1579         }
1580 }