Current File : /www/varak.net/wiki.varak.net/includes/libs/rdbms/database/position/MySQLMasterPos.php
<?php
namespace Wikimedia\Rdbms;
use InvalidArgumentException;
use UnexpectedValueException;
/**
* DBMasterPos class for MySQL/MariaDB
*
* Note that master positions and sync logic here make some assumptions:
* - Binlog-based usage assumes single-source replication and non-hierarchical replication.
* - GTID-based usage allows getting/syncing with multi-source replication. It is assumed
* that GTID sets are complete (e.g. include all domains on the server).
*
* @see https://mariadb.com/kb/en/library/gtid/
* @see https://dev.mysql.com/doc/refman/5.6/en/replication-gtids-concepts.html
*/
class MySQLMasterPos implements DBMasterPos {
/** @var int One of (BINARY_LOG, GTID_MYSQL, GTID_MARIA) */
private $style;
/** @var string|null Base name of all Binary Log files */
private $binLog;
/** @var int[]|null Binary Log position tuple (index number, event number) */
private $logPos;
/** @var string[] Map of (server_uuid/gtid_domain_id => GTID) */
private $gtids = [];
/** @var int|null Active GTID domain ID */
private $activeDomain;
/** @var int|null ID of the server were DB writes originate */
private $activeServerId;
/** @var string|null UUID of the server were DB writes originate */
private $activeServerUUID;
/** @var float UNIX timestamp */
private $asOfTime = 0.0;
const BINARY_LOG = 'binary-log';
const GTID_MARIA = 'gtid-maria';
const GTID_MYSQL = 'gtid-mysql';
/** @var int Key name of the binary log index number of a position tuple */
const CORD_INDEX = 0;
/** @var int Key name of the binary log event number of a position tuple */
const CORD_EVENT = 1;
/**
* @param string $position One of (comma separated GTID list, <binlog file>/<integer>)
* @param float $asOfTime UNIX timestamp
*/
public function __construct( $position, $asOfTime ) {
$this->init( $position, $asOfTime );
}
/**
* @param string $position
* @param float $asOfTime
*/
protected function init( $position, $asOfTime ) {
$m = [];
if ( preg_match( '!^(.+)\.(\d+)/(\d+)$!', $position, $m ) ) {
$this->binLog = $m[1]; // ideally something like host name
$this->logPos = [ self::CORD_INDEX => (int)$m[2], self::CORD_EVENT => (int)$m[3] ];
$this->style = self::BINARY_LOG;
} else {
$gtids = array_filter( array_map( 'trim', explode( ',', $position ) ) );
foreach ( $gtids as $gtid ) {
$components = self::parseGTID( $gtid );
if ( !$components ) {
throw new InvalidArgumentException( "Invalid GTID '$gtid'." );
}
list( $domain, $pos ) = $components;
if ( isset( $this->gtids[$domain] ) ) {
// For MySQL, handle the case where some past issue caused a gap in the
// executed GTID set, e.g. [last_purged+1,N-1] and [N+1,N+2+K]. Ignore the
// gap by using the GTID with the highest ending sequence number.
list( , $otherPos ) = self::parseGTID( $this->gtids[$domain] );
if ( $pos > $otherPos ) {
$this->gtids[$domain] = $gtid;
}
} else {
$this->gtids[$domain] = $gtid;
}
if ( is_int( $domain ) ) {
$this->style = self::GTID_MARIA; // gtid_domain_id
} else {
$this->style = self::GTID_MYSQL; // server_uuid
}
}
if ( !$this->gtids ) {
throw new InvalidArgumentException( "GTID set cannot be empty." );
}
}
$this->asOfTime = $asOfTime;
}
public function asOfTime() {
return $this->asOfTime;
}
public function hasReached( DBMasterPos $pos ) {
if ( !( $pos instanceof self ) ) {
throw new InvalidArgumentException( "Position not an instance of " . __CLASS__ );
}
// Prefer GTID comparisons, which work with multi-tier replication
$thisPosByDomain = $this->getActiveGtidCoordinates();
$thatPosByDomain = $pos->getActiveGtidCoordinates();
if ( $thisPosByDomain && $thatPosByDomain ) {
$comparisons = [];
// Check that this has positions reaching those in $pos for all domains in common
foreach ( $thatPosByDomain as $domain => $thatPos ) {
if ( isset( $thisPosByDomain[$domain] ) ) {
$comparisons[] = ( $thatPos <= $thisPosByDomain[$domain] );
}
}
// Check that $this has a GTID for at least one domain also in $pos; due to MariaDB
// quirks, prior master switch-overs may result in inactive garbage GTIDs that cannot
// be cleaned up. Assume that the domains in both this and $pos cover the relevant
// active channels.
return ( $comparisons && !in_array( false, $comparisons, true ) );
}
// Fallback to the binlog file comparisons
$thisBinPos = $this->getBinlogCoordinates();
$thatBinPos = $pos->getBinlogCoordinates();
if ( $thisBinPos && $thatBinPos && $thisBinPos['binlog'] === $thatBinPos['binlog'] ) {
return ( $thisBinPos['pos'] >= $thatBinPos['pos'] );
}
// Comparing totally different binlogs does not make sense
return false;
}
public function channelsMatch( DBMasterPos $pos ) {
if ( !( $pos instanceof self ) ) {
throw new InvalidArgumentException( "Position not an instance of " . __CLASS__ );
}
// Prefer GTID comparisons, which work with multi-tier replication
$thisPosDomains = array_keys( $this->getActiveGtidCoordinates() );
$thatPosDomains = array_keys( $pos->getActiveGtidCoordinates() );
if ( $thisPosDomains && $thatPosDomains ) {
// Check that $this has a GTID for at least one domain also in $pos; due to MariaDB
// quirks, prior master switch-overs may result in inactive garbage GTIDs that cannot
// easily be cleaned up. Assume that the domains in both this and $pos cover the
// relevant active channels.
return array_intersect( $thatPosDomains, $thisPosDomains ) ? true : false;
}
// Fallback to the binlog file comparisons
$thisBinPos = $this->getBinlogCoordinates();
$thatBinPos = $pos->getBinlogCoordinates();
return ( $thisBinPos && $thatBinPos && $thisBinPos['binlog'] === $thatBinPos['binlog'] );
}
/**
* @return string|null Base name of binary log files
* @since 1.31
*/
public function getLogName() {
return $this->gtids ? null : $this->binLog;
}
/**
* @return int[]|null Tuple of (binary log file number, event number)
* @since 1.31
*/
public function getLogPosition() {
return $this->gtids ? null : $this->logPos;
}
/**
* @return string|null Name of the binary log file for this position
* @since 1.31
*/
public function getLogFile() {
return $this->gtids ? null : "{$this->binLog}.{$this->logPos[self::CORD_INDEX]}";
}
/**
* @return string[] Map of (server_uuid/gtid_domain_id => GTID)
* @since 1.31
*/
public function getGTIDs() {
return $this->gtids;
}
/**
* @param int|null $id @@gtid_domain_id of the active replication stream
* @since 1.31
*/
public function setActiveDomain( $id ) {
$this->activeDomain = (int)$id;
}
/**
* @param int|null $id @@server_id of the server were writes originate
* @since 1.31
*/
public function setActiveOriginServerId( $id ) {
$this->activeServerId = (int)$id;
}
/**
* @param string|null $id @@server_uuid of the server were writes originate
* @since 1.31
*/
public function setActiveOriginServerUUID( $id ) {
$this->activeServerUUID = $id;
}
/**
* @param MySQLMasterPos $pos
* @param MySQLMasterPos $refPos
* @return string[] List of GTIDs from $pos that have domains in $refPos
* @since 1.31
*/
public static function getCommonDomainGTIDs( MySQLMasterPos $pos, MySQLMasterPos $refPos ) {
return array_values(
array_intersect_key( $pos->gtids, $refPos->getActiveGtidCoordinates() )
);
}
/**
* @see https://mariadb.com/kb/en/mariadb/gtid
* @see https://dev.mysql.com/doc/refman/5.6/en/replication-gtids-concepts.html
* @return array Map of (server_uuid/gtid_domain_id => integer position); possibly empty
*/
protected function getActiveGtidCoordinates() {
$gtidInfos = [];
foreach ( $this->gtids as $domain => $gtid ) {
list( $domain, $pos, $server ) = self::parseGTID( $gtid );
$ignore = false;
// Filter out GTIDs from non-active replication domains
if ( $this->style === self::GTID_MARIA && $this->activeDomain !== null ) {
$ignore |= ( $domain !== $this->activeDomain );
}
// Likewise for GTIDs from non-active replication origin servers
if ( $this->style === self::GTID_MARIA && $this->activeServerId !== null ) {
$ignore |= ( $server !== $this->activeServerId );
} elseif ( $this->style === self::GTID_MYSQL && $this->activeServerUUID !== null ) {
$ignore |= ( $server !== $this->activeServerUUID );
}
if ( !$ignore ) {
$gtidInfos[$domain] = $pos;
}
}
return $gtidInfos;
}
/**
* @param string $id GTID
* @return array|null [domain ID or server UUID, sequence number, server ID/UUID] or null
*/
protected static function parseGTID( $id ) {
$m = [];
if ( preg_match( '!^(\d+)-(\d+)-(\d+)$!', $id, $m ) ) {
// MariaDB style: <domain>-<server id>-<sequence number>
return [ (int)$m[1], (int)$m[3], (int)$m[2] ];
} elseif ( preg_match( '!^(\w{8}-\w{4}-\w{4}-\w{4}-\w{12}):(?:\d+-|)(\d+)$!', $id, $m ) ) {
// MySQL style: <server UUID>:<sequence number>-<sequence number>
// Normally, the first number should reflect the point (gtid_purged) where older
// binary logs where purged to save space. When doing comparisons, it may as well
// be 1 in that case. Assume that this is generally the situation.
return [ $m[1], (int)$m[2], $m[1] ];
}
return null;
}
/**
* @see https://dev.mysql.com/doc/refman/5.7/en/show-master-status.html
* @see https://dev.mysql.com/doc/refman/5.7/en/show-slave-status.html
* @return array|bool Map of (binlog:<string>, pos:(<integer>, <integer>)) or false
*/
protected function getBinlogCoordinates() {
return ( $this->binLog !== null && $this->logPos !== null )
? [ 'binlog' => $this->binLog, 'pos' => $this->logPos ]
: false;
}
public function serialize() {
return serialize( [
'position' => $this->__toString(),
'activeDomain' => $this->activeDomain,
'activeServerId' => $this->activeServerId,
'activeServerUUID' => $this->activeServerUUID,
'asOfTime' => $this->asOfTime
] );
}
public function unserialize( $serialized ) {
$data = unserialize( $serialized );
if ( !is_array( $data ) ) {
throw new UnexpectedValueException( __METHOD__ . ": cannot unserialize position" );
}
$this->init( $data['position'], $data['asOfTime'] );
if ( isset( $data['activeDomain'] ) ) {
$this->setActiveDomain( $data['activeDomain'] );
}
if ( isset( $data['activeServerId'] ) ) {
$this->setActiveOriginServerId( $data['activeServerId'] );
}
if ( isset( $data['activeServerUUID'] ) ) {
$this->setActiveOriginServerUUID( $data['activeServerUUID'] );
}
}
/**
* @return string GTID set or <binary log file>/<position> (e.g db1034-bin.000976/843431247)
*/
public function __toString() {
return $this->gtids
? implode( ',', $this->gtids )
: $this->getLogFile() . "/{$this->logPos[self::CORD_EVENT]}";
}
}
Mini Shell