25 use \Wikimedia\WaitConditionLoop;
100 $this->attrMap[self::ATTR_EMULATION] = self::QOS_EMULATION_SQL;
101 $this->attrMap[self::ATTR_SYNCWRITES] = self::QOS_SYNCWRITES_NONE;
103 if ( isset(
$params[
'servers'] ) ) {
104 $this->serverInfos = [];
105 $this->serverTags = [];
106 $this->numServers = count(
$params[
'servers'] );
109 $this->serverInfos[$index] = $info;
110 if ( is_string(
$tag ) ) {
111 $this->serverTags[$index] =
$tag;
113 $this->serverTags[$index] = isset( $info[
'host'] ) ? $info[
'host'] :
"#$index";
117 } elseif ( isset(
$params[
'server'] ) ) {
118 $this->serverInfos = [
$params[
'server'] ];
119 $this->numServers = count( $this->serverInfos );
122 $this->serverInfos =
false;
123 $this->numServers = 1;
124 $this->attrMap[self::ATTR_SYNCWRITES] = self::QOS_SYNCWRITES_BE;
126 if ( isset(
$params[
'purgePeriod'] ) ) {
127 $this->purgePeriod = intval(
$params[
'purgePeriod'] );
129 if ( isset(
$params[
'tableName'] ) ) {
132 if ( isset(
$params[
'shards'] ) ) {
133 $this->shards = intval(
$params[
'shards'] );
135 if ( isset(
$params[
'syncTimeout'] ) ) {
136 $this->syncTimeout =
$params[
'syncTimeout'];
138 $this->replicaOnly = !empty(
$params[
'slaveOnly'] );
144 if ( $wgDBtype ===
'mysql' && $this->
usesMainDB() ) {
145 if ( !$this->separateMainLB ) {
147 $lbFactory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
148 $this->separateMainLB =
$lbFactory->newMainLB();
165 protected function getDB( $serverIndex ) {
166 if ( !isset( $this->conns[$serverIndex] ) ) {
167 if ( $serverIndex >= $this->numServers ) {
168 throw new MWException( __METHOD__ .
": Invalid server index \"$serverIndex\"" );
171 # Don't keep timing out trying to connect for each call if the DB is down
172 if ( isset( $this->connFailureErrors[$serverIndex] )
173 && ( time() - $this->connFailureTimes[$serverIndex] ) < 60
175 throw $this->connFailureErrors[$serverIndex];
178 # If server connection info was given, use that
179 if ( $this->serverInfos ) {
180 $info = $this->serverInfos[$serverIndex];
181 $type = isset( $info[
'type'] ) ? $info[
'type'] :
'mysql';
182 $host = isset( $info[
'host'] ) ? $info[
'host'] :
'[unknown]';
183 $this->logger->debug( __CLASS__ .
": connecting to $host" );
198 $this->logger->debug( sprintf(
"Connection %s will be used for SqlBagOStuff", $db ) );
199 $this->conns[$serverIndex] = $db;
202 return $this->conns[$serverIndex];
211 if ( $this->shards > 1 ) {
212 $hash = hexdec( substr( md5( $key ), 0, 8 ) ) & 0x7fffffff;
217 if ( $this->numServers > 1 ) {
220 reset( $sortedServers );
221 $serverIndex =
key( $sortedServers );
234 if ( $this->shards > 1 ) {
235 $decimals = strlen( $this->shards - 1 );
237 sprintf(
"%0{$decimals}d", $index );
250 $values = $this->
getMulti( [ $key ] );
251 if ( array_key_exists( $key, $values ) ) {
252 $casToken = $values[$key];
253 return $values[$key];
262 foreach ( $keys
as $key ) {
264 $keysByTable[$serverIndex][
$tableName][] = $key;
270 foreach ( $keysByTable
as $serverIndex => $serverKeys ) {
272 $db = $this->
getDB( $serverIndex );
275 [
'keyname',
'value',
'exptime' ],
276 [
'keyname' => $tableKeys ],
281 $db->trxLevel() ? [
'LOCK IN SHARE MODE' ] : []
283 if (
$res ===
false ) {
286 foreach (
$res as $row ) {
287 $row->serverIndex = $serverIndex;
289 $dataRows[$row->keyname] = $row;
297 foreach ( $keys
as $key ) {
298 if ( isset( $dataRows[$key] ) ) {
299 $row = $dataRows[$key];
300 $this->
debug(
"get: retrieved data; expiry time is " . $row->exptime );
303 $db = $this->
getDB( $row->serverIndex );
304 if ( $this->
isExpired( $db, $row->exptime ) ) {
305 $this->
debug(
"get: key has expired" );
307 $values[$key] = $this->
unserialize( $db->decodeBlob( $row->value ) );
313 $this->
debug(
'get: no matching rows' );
322 foreach ( $data
as $key =>
$value ) {
324 $keysByTable[$serverIndex][
$tableName][] = $key;
330 $exptime = (int)$expiry;
331 foreach ( $keysByTable
as $serverIndex => $serverKeys ) {
334 $db = $this->
getDB( $serverIndex );
341 if ( $exptime < 0 ) {
345 if ( $exptime == 0 ) {
349 $encExpiry = $db->timestamp( $exptime );
353 foreach ( $tableKeys
as $key ) {
356 'value' => $db->encodeBlob( $this->
serialize( $data[$key] ) ),
357 'exptime' => $encExpiry,
382 if ( (
$flags & self::WRITE_SYNC ) == self::WRITE_SYNC ) {
389 protected function cas( $casToken, $key,
$value, $exptime = 0 ) {
393 $db = $this->
getDB( $serverIndex );
394 $exptime = intval( $exptime );
396 if ( $exptime < 0 ) {
400 if ( $exptime == 0 ) {
404 $encExpiry = $db->timestamp( $exptime );
412 'value' => $db->encodeBlob( $this->serialize(
$value ) ),
413 'exptime' => $encExpiry
417 'value' => $db->encodeBlob( $this->serialize( $casToken ) )
427 return (
bool)$db->affectedRows();
430 public function delete( $key ) {
434 $db = $this->
getDB( $serverIndex );
437 [
'keyname' => $key ],
447 public function incr( $key, $step = 1 ) {
451 $db = $this->
getDB( $serverIndex );
452 $step = intval( $step );
453 $row = $db->selectRow(
455 [
'value',
'exptime' ],
456 [
'keyname' => $key ],
459 if ( $row ===
false ) {
464 $db->delete(
$tableName, [
'keyname' => $key ], __METHOD__ );
465 if ( $this->
isExpired( $db, $row->exptime ) ) {
471 $oldValue = intval( $this->
unserialize( $db->decodeBlob( $row->value ) ) );
472 $newValue = $oldValue + $step;
476 'value' => $db->encodeBlob( $this->serialize( $newValue ) ),
477 'exptime' => $row->exptime
478 ], __METHOD__,
'IGNORE' );
480 if ( $db->affectedRows() == 0 ) {
492 public function merge( $key, callable $callback, $exptime = 0, $attempts = 10,
$flags = 0 ) {
493 $ok = $this->
mergeViaCas( $key, $callback, $exptime, $attempts );
494 if ( (
$flags & self::WRITE_SYNC ) == self::WRITE_SYNC ) {
505 $db = $this->
getDB( $serverIndex );
508 [
'exptime' => $db->timestamp( $this->convertExpiry( $expiry ) ) ],
509 [
'keyname' => $key,
'exptime > ' . $db->addQuotes( $db->timestamp( time() ) ) ],
512 if ( $db->affectedRows() == 0 ) {
537 if ( time() > 0x7fffffff ) {
538 return $db->timestamp( 1 << 62 );
540 return $db->timestamp( 0x7fffffff );
545 if ( !$this->purgePeriod || $this->replicaOnly ) {
550 if ( $this->purgePeriod !== 1 && mt_rand( 0, $this->purgePeriod - 1 ) ) {
555 if ( $now > ( $this->lastExpireAll + 1 ) ) {
556 $this->lastExpireAll = $now;
575 $db = $this->
getDB( $serverIndex );
577 $totalSeconds =
false;
578 $baseConds = [
'exptime < ' . $db->addQuotes( $dbTimestamp ) ];
583 if ( $maxExpTime !==
false ) {
584 $conds[] =
'exptime > ' . $db->addQuotes( $maxExpTime );
588 [
'keyname',
'exptime' ],
591 [
'LIMIT' => 100,
'ORDER BY' =>
'exptime' ] );
592 if ( $rows ===
false || !$rows->numRows() ) {
596 $row = $rows->current();
597 $minExpTime = $row->exptime;
598 if ( $totalSeconds ===
false ) {
602 foreach ( $rows
as $row ) {
603 $keys[] = $row->keyname;
604 $maxExpTime = $row->exptime;
610 'exptime >= ' . $db->addQuotes( $minExpTime ),
611 'exptime < ' . $db->addQuotes( $dbTimestamp ),
616 if ( $progressCallback ) {
617 if ( intval( $totalSeconds ) === 0 ) {
622 if ( $remainingSeconds > $totalSeconds ) {
623 $totalSeconds = $remainingSeconds;
625 $processedSeconds = $totalSeconds - $remainingSeconds;
626 $percent = ( $i + $processedSeconds / $totalSeconds )
627 / $this->shards * 100;
630 + ( $serverIndex / $this->numServers * 100 );
631 call_user_func( $progressCallback, $percent );
652 $db = $this->
getDB( $serverIndex );
675 if ( function_exists(
'gzdeflate' ) ) {
676 return gzdeflate( $serial );
688 if ( function_exists(
'gzinflate' ) ) {
689 MediaWiki\suppressWarnings();
690 $decomp = gzinflate( $serial );
691 MediaWiki\restoreWarnings();
693 if (
false !== $decomp ) {
713 $this->logger->error(
"DBError: {$exception->getMessage()}" );
714 if ( $exception instanceof DBConnectionError ) {
716 $this->logger->debug( __METHOD__ .
": ignoring connection error" );
719 $this->logger->debug( __METHOD__ .
": ignoring query error" );
734 } elseif ( $db->wasReadOnlyError() ) {
735 if ( $db->trxLevel() && $this->
usesMainDB() ) {
743 $this->logger->error(
"DBError: {$exception->getMessage()}" );
746 $this->logger->debug( __METHOD__ .
": ignoring connection error" );
749 $this->logger->debug( __METHOD__ .
": ignoring query error" );
760 unset( $this->conns[$serverIndex] );
762 if ( isset( $this->connFailureTimes[$serverIndex] ) ) {
763 if ( time() - $this->connFailureTimes[$serverIndex] >= 60 ) {
764 unset( $this->connFailureTimes[$serverIndex] );
765 unset( $this->connFailureErrors[$serverIndex] );
767 $this->logger->debug( __METHOD__ .
": Server #$serverIndex already down" );
772 $this->logger->info( __METHOD__ .
": Server #$serverIndex down until " . ( $now + 60 ) );
773 $this->connFailureTimes[$serverIndex] = $now;
774 $this->connFailureErrors[$serverIndex] = $exception;
782 $db = $this->
getDB( $serverIndex );
783 if ( $db->getType() !==
'mysql' ) {
784 throw new MWException( __METHOD__ .
' is not supported on this DB server' );
789 'CREATE TABLE ' . $db->tableName( $this->getTableNameByShard( $i ) ) .
790 ' LIKE ' . $db->tableName(
'objectcache' ),
810 ?: MediaWikiServices::getInstance()->getDBLoadBalancer();
812 if ( $lb->getServerCount() <= 1 ) {
817 $masterPos = $lb->getMasterPos();
819 $loop =
new WaitConditionLoop(
820 function ()
use ( $lb, $masterPos ) {
821 return $lb->waitForAll( $masterPos, 1 );
827 return ( $loop->invoke() === $loop::CONDITION_REACHED );
static consistentHashSort(&$array, $key, $separator="\000")
Sort the given array in a pseudo-random order which depends only on the given key and each element va...
getWithToken($key, &$casToken, $flags=0)
deferred txt A few of the database updates required by various functions here can be deferred until after the result page is displayed to the user For updating the view updating the linked to tables after a etc PHP does not yet have any way to tell the server to actually return and disconnect while still running these but it might have such a feature in the future We handle these by creating a deferred update object and putting those objects on a global list
wfGetDB($db, $groups=[], $wiki=false)
Get a Database object.
Database error base class.
the array() calling protocol came about after MediaWiki 1.4rc1.
static factory($dbType, $p=[])
Construct a Database subclass instance given a database type and parameters.
null means default in associative array with keys and values unescaped Should be merged with default with a value of false meaning to suppress the attribute in associative array with keys and values unescaped noclasses & $ret
Apache License January AND DISTRIBUTION Definitions License shall mean the terms and conditions for use
array[] $serverInfos
(server index => server config)
div flags Integer display flags(NO_ACTION_LINK, NO_EXTRA_USER_LINKS) 'LogException'returning false will NOT prevent logging $e
__construct($params)
Constructor.
injection txt This is an overview of how MediaWiki makes use of dependency injection The design described here grew from the discussion of RFC T384 The term dependency this means that anything an object needs to operate should be injected from the the object itself should only know narrow no concrete implementation of the logic it relies on The requirement to inject everything typically results in an architecture that based on two main types of and essentially stateless service objects that use other service objects to operate on the value objects As of the beginning MediaWiki is only starting to use the DI approach Much of the code still relies on global state or direct resulting in a highly cyclical dependency MediaWikiServices
it s the revision text itself In either if gzip is the revision text is gzipped $flags
unserialize($serial)
Unserialize and, if necessary, decompress an object.
cas($casToken, $key, $value, $exptime=0)
when a variable name is used in a it is silently declared as a new local masking the global
handleWriteError(DBError $exception, IDatabase $db=null, $serverIndex)
Handle a DBQueryError which occurred during a write operation.
We use the convention $dbr for read and $dbw for write to help you keep track of whether the database object is a the world will explode Or to be a subsequent write query which succeeded on the master may fail when replicated to the slave due to a unique key collision Replication on the slave will stop and it may take hours to repair the database and get it back online Setting read_only in my cnf on the slave will avoid this but given the dire we prefer to have as many checks as possible We provide a but the wrapper functions like please read the documentation for tableName() and addQuotes().You will need both of them.------------------------------------------------------------------------Basic query optimisation------------------------------------------------------------------------MediaWiki developers who need to write DB queries should have some understanding of databases and the performance issues associated with them.Patches containing unacceptably slow features will not be accepted.Unindexed queries are generally not welcome in MediaWiki
The index of the header message $result[1]=The index of the body text message $result[2 through n]=Parameters passed to body text message.Please note the header message cannot receive/use parameters. 'ImportHandleLogItemXMLTag':When parsing a XML tag in a log item.Return false to stop further processing of the tag $reader:XMLReader object $logInfo:Array of information 'ImportHandlePageXMLTag':When parsing a XML tag in a page.Return false to stop further processing of the tag $reader:XMLReader object &$pageInfo:Array of information 'ImportHandleRevisionXMLTag':When parsing a XML tag in a page revision.Return false to stop further processing of the tag $reader:XMLReader object $pageInfo:Array of page information $revisionInfo:Array of revision information 'ImportHandleToplevelXMLTag':When parsing a top level XML tag.Return false to stop further processing of the tag $reader:XMLReader object 'ImportHandleUploadXMLTag':When parsing a XML tag in a file upload.Return false to stop further processing of the tag $reader:XMLReader object $revisionInfo:Array of information 'ImportLogInterwikiLink':Hook to change the interwiki link used in log entries and edit summaries for transwiki imports.&$fullInterwikiPrefix:Interwiki prefix, may contain colons.&$pageTitle:String that contains page title. 'ImportSources':Called when reading from the $wgImportSources configuration variable.Can be used to lazy-load the import sources list.&$importSources:The value of $wgImportSources.Modify as necessary.See the comment in DefaultSettings.php for the detail of how to structure this array. 'InfoAction':When building information to display on the action=info page.$context:IContextSource object &$pageInfo:Array of information 'InitializeArticleMaybeRedirect':MediaWiki check to see if title is a redirect.&$title:Title object for the current page &$request:WebRequest &$ignoreRedirect:boolean to skip redirect check &$target:Title/string of redirect target &$article:Article object 'InternalParseBeforeLinks':during Parser's internalParse method before links but after nowiki/noinclude/includeonly/onlyinclude and other processings.&$parser:Parser object &$text:string containing partially parsed text &$stripState:Parser's internal StripState object 'InternalParseBeforeSanitize':during Parser's internalParse method just before the parser removes unwanted/dangerous HTML tags and after nowiki/noinclude/includeonly/onlyinclude and other processings.Ideal for syntax-extensions after template/parser function execution which respect nowiki and HTML-comments.&$parser:Parser object &$text:string containing partially parsed text &$stripState:Parser's internal StripState object 'InterwikiLoadPrefix':When resolving if a given prefix is an interwiki or not.Return true without providing an interwiki to continue interwiki search.$prefix:interwiki prefix we are looking for.&$iwData:output array describing the interwiki with keys iw_url, iw_local, iw_trans and optionally iw_api and iw_wikiid. 'InvalidateEmailComplete':Called after a user's email has been invalidated successfully.$user:user(object) whose email is being invalidated 'IRCLineURL':When constructing the URL to use in an IRC notification.Callee may modify $url and $query, URL will be constructed as $url.$query &$url:URL to index.php &$query:Query string $rc:RecentChange object that triggered url generation 'IsFileCacheable':Override the result of Article::isFileCacheable()(if true) &$article:article(object) being checked 'IsTrustedProxy':Override the result of IP::isTrustedProxy() &$ip:IP being check &$result:Change this value to override the result of IP::isTrustedProxy() 'IsUploadAllowedFromUrl':Override the result of UploadFromUrl::isAllowedUrl() $url:URL used to upload from &$allowed:Boolean indicating if uploading is allowed for given URL 'isValidEmailAddr':Override the result of Sanitizer::validateEmail(), for instance to return false if the domain name doesn't match your organization.$addr:The e-mail address entered by the user &$result:Set this and return false to override the internal checks 'isValidPassword':Override the result of User::isValidPassword() $password:The password entered by the user &$result:Set this and return false to override the internal checks $user:User the password is being validated for 'Language::getMessagesFileName':$code:The language code or the language we're looking for a messages file for &$file:The messages file path, you can override this to change the location. 'LanguageGetMagic':DEPRECATED!Use $magicWords in a file listed in $wgExtensionMessagesFiles instead.Use this to define synonyms of magic words depending of the language &$magicExtensions:associative array of magic words synonyms $lang:language code(string) 'LanguageGetNamespaces':Provide custom ordering for namespaces or remove namespaces.Do not use this hook to add namespaces.Use CanonicalNamespaces for that.&$namespaces:Array of namespaces indexed by their numbers 'LanguageGetSpecialPageAliases':DEPRECATED!Use $specialPageAliases in a file listed in $wgExtensionMessagesFiles instead.Use to define aliases of special pages names depending of the language &$specialPageAliases:associative array of magic words synonyms $lang:language code(string) 'LanguageGetTranslatedLanguageNames':Provide translated language names.&$names:array of language code=> language name $code:language of the preferred translations 'LanguageLinks':Manipulate a page's language links.This is called in various places to allow extensions to define the effective language links for a page.$title:The page's Title.&$links:Associative array mapping language codes to prefixed links of the form"language:title".&$linkFlags:Associative array mapping prefixed links to arrays of flags.Currently unused, but planned to provide support for marking individual language links in the UI, e.g.for featured articles. 'LanguageSelector':Hook to change the language selector available on a page.$out:The output page.$cssClassName:CSS class name of the language selector. 'LinkBegin':DEPRECATED!Use HtmlPageLinkRendererBegin instead.Used when generating internal and interwiki links in Linker::link(), before processing starts.Return false to skip default processing and return $ret.See documentation for Linker::link() for details on the expected meanings of parameters.$skin:the Skin object $target:the Title that the link is pointing to &$html:the contents that the< a > tag should have(raw HTML) $result
const TS_UNIX
Unix time - the number of seconds since 1970-01-01 00:00:00 UTC.
wfTimestamp($outputtype=TS_UNIX, $ts=0)
Get a timestamp string in one of various formats.
mergeViaCas($key, $callback, $exptime=0, $attempts=10)
handleReadError(DBError $exception, $serverIndex)
Handle a DBError which occurred during a read operation.
callable[] $busyCallbacks
convertExpiry($exptime)
Convert an optionally relative time to an absolute time.
design txt This is a brief overview of the new design More thorough and up to date information is available on the documentation wiki at etc Handles the details of getting and saving to the user table of the and dealing with sessions and cookies OutputPage Encapsulates the entire HTML page that will be sent in response to any server request It is used by calling its functions to add in any and then calling but I prefer the flexibility This should also do the output encoding The system allocates a global one in $wgOut Title Represents the title of an and does all the work of translating among various forms such as plain database key
string[] $serverTags
(server index => tag/host name)
getMulti(array $keys, $flags=0)
Helper class that detects high-contention DB queries via profiling calls.
markServerDown(DBError $exception, $serverIndex)
Mark a server down due to a DBConnectionError exception.
wfTimestampNow()
Convenience function; returns MediaWiki timestamp for the present time.
getTableByKey($key)
Get the server index and table name for a given key.
createTables()
Create shard tables.
setMulti(array $data, $expiry=0)
this hook is for auditing only RecentChangesLinked and Watchlist RecentChangesLinked and Watchlist e g Watchlist removed from all revisions and log entries to which it was applied This gives extensions a chance to take it off their books $tag
set($key, $value, $exptime=0, $flags=0)
deleteAll()
Delete content of shard tables in every server.
This document is intended to provide useful advice for parties seeking to redistribute MediaWiki to end users It s targeted particularly at maintainers for Linux since it s been observed that distribution packages of MediaWiki often break We ve consistently had to recommend that users seeking support use official tarballs instead of their distribution s and this often solves whatever problem the user is having It would be nice if this could such as
LoadBalancer null $separateMainLB
injection txt This is an overview of how MediaWiki makes use of dependency injection The design described here grew from the discussion of RFC T384 The term dependency this means that anything an object needs to operate should be injected from the the object itself should only know narrow no concrete implementation of the logic it relies on The requirement to inject everything typically results in an architecture that based on two main types of and essentially stateless service objects that use other service objects to operate on the value objects As of the beginning MediaWiki is only starting to use the DI approach Much of the code still relies on global state or direct resulting in a highly cyclical dependency which acts as the top level factory for services in MediaWiki which can be used to gain access to default instances of various services MediaWikiServices however also allows new services to be defined and default services to be redefined Services are defined or redefined by providing a callback the instantiator that will return a new instance of the service When it will create an instance of MediaWikiServices and populate it with the services defined in the files listed by thereby bootstrapping the DI framework Per $wgServiceWiringFiles lists includes ServiceWiring php
changeTTL($key, $expiry=0)
array $connFailureTimes
UNIX timestamps.
serialize(&$data)
Serialize an object and, if possible, compress the representation.
Class to store objects in the database.
setLastError($err)
Set the "last error" registry.
getTableNameByShard($index)
Get the table name for a given shard index.
do that in ParserLimitReportFormat instead use this to modify the parameters of the image and a DIV can begin in one section and end in another Make sure your code can handle that case gracefully See the EditSectionClearerLink extension for an example zero but section is usually empty its values are the globals values before the output is cached one of or reset my talk my contributions etc etc otherwise the built in rate limiting checks are if enabled allows for interception of redirect as a string mapping parameter names to values & $type
merge($key, callable $callback, $exptime=0, $attempts=10, $flags=0)
array $connFailureErrors
Exceptions.
Basic database interface for live and lazy-loaded relation database handles.
getDB($serverIndex)
Get a connection to the specified database.
deleteObjectsExpiringBefore($timestamp, $progressCallback=false)
Delete objects from the database which expire before a certain date.