MediaWiki  1.23.12
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1 <?php
25 require_once __DIR__ . '/Maintenance.php';
34  const REPORTING_INTERVAL = 1000;
36  public function __construct() {
37  parent::__construct();
38  $this->mDescription = <<<TEXT
39 This script will populate the category table, added in MediaWiki 1.13. It will
40 print out progress indicators every 1000 categories it adds to the table. The
41 script is perfectly safe to run on large, live wikis, and running it multiple
42 times is harmless. You may want to use the throttling options if it's causing
43 too much load; they will not affect correctness.
45 If the script is stopped and later resumed, you can use the --begin option with
46 the last printed progress indicator to pick up where you left off. This is
47 safe, because any newly-added categories before this cutoff will have been
48 added after the software update and so will be populated anyway.
50 When the script has finished, it will make a note of this in the database, and
51 will not run again without the --force option.
52 TEXT;
53 # '
54  $this->addOption( 'begin', 'Only do categories whose names are alphabetically after the provided name', false, true );
55  $this->addOption( 'max-slave-lag', 'If slave lag exceeds this many seconds, wait until it drops before continuing. Default: 10', false, true );
56  $this->addOption( 'throttle', 'Wait this many milliseconds after each category. Default: 0', false, true );
57  $this->addOption( 'force', 'Run regardless of whether the database says it\'s been run already' );
58  }
60  public function execute() {
61  $begin = $this->getOption( 'begin', '' );
62  $maxSlaveLag = $this->getOption( 'max-slave-lag', 10 );
63  $throttle = $this->getOption( 'throttle', 0 );
64  $force = $this->getOption( 'force', false );
65  $this->doPopulateCategory( $begin, $maxSlaveLag, $throttle, $force );
66  }
68  private function doPopulateCategory( $begin, $maxlag, $throttle, $force ) {
69  $dbw = wfGetDB( DB_MASTER );
71  if ( !$force ) {
72  $row = $dbw->selectRow(
73  'updatelog',
74  '1',
75  array( 'ul_key' => 'populate category' ),
76  __METHOD__
77  );
78  if ( $row ) {
79  $this->output( "Category table already populated. Use php " .
80  "maintenance/populateCategory.php\n--force from the command line " .
81  "to override.\n" );
82  return true;
83  }
84  }
86  $throttle = intval( $throttle );
87  if ( $begin !== '' ) {
88  $where = 'cl_to > ' . $dbw->addQuotes( $begin );
89  } else {
90  $where = null;
91  }
92  $i = 0;
94  while ( true ) {
95  # Find which category to update
96  $row = $dbw->selectRow(
97  'categorylinks',
98  'cl_to',
99  $where,
100  __METHOD__,
101  array(
102  'ORDER BY' => 'cl_to'
103  )
104  );
105  if ( !$row ) {
106  # Done, hopefully.
107  break;
108  }
109  $name = $row->cl_to;
110  $where = 'cl_to > ' . $dbw->addQuotes( $name );
112  # Use the row to update the category count
113  $cat = Category::newFromName( $name );
114  if ( !is_object( $cat ) ) {
115  $this->output( "The category named $name is not valid?!\n" );
116  } else {
117  $cat->refreshCounts();
118  }
120  ++$i;
121  if ( !( $i % self::REPORTING_INTERVAL ) ) {
122  $this->output( "$name\n" );
123  wfWaitForSlaves();
124  }
125  usleep( $throttle * 1000 );
126  }
128  if ( $dbw->insert(
129  'updatelog',
130  array( 'ul_key' => 'populate category' ),
131  __METHOD__,
132  'IGNORE'
133  )
134  ) {
135  $this->output( "Category population complete.\n" );
136  return true;
137  } else {
138  $this->output( "Could not insert category population row.\n" );
139  return false;
140  }
141  }
142 }
144 $maintClass = "PopulateCategory";
145 require_once RUN_MAINTENANCE_IF_MAIN;
Definition: Defines.php:56
skin txt MediaWiki includes four core it has been set as the default in MediaWiki since the replacing Monobook it had been been the default skin since before being replaced by Vector largely rewritten in while keeping its appearance Several legacy skins were removed in the as the burden of supporting them became too heavy to bear Those in etc for skin dependent CSS etc for skin dependent JavaScript These can also be customised on a per user by etc This feature has led to a wide variety of user styles becoming that gallery is a good place to ending in php
Definition: skin.txt:62
Mainteance script to populate the category table.
Definition: populateCategory.php:32
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 except in special pages derived from QueryPage It s a common pitfall for new developers to submit code containing SQL queries which examine huge numbers of rows Remember that COUNT * is(N), counting rows in atable is like counting beans in a bucket.------------------------------------------------------------------------ Replication------------------------------------------------------------------------The largest installation of MediaWiki, Wikimedia, uses a large set ofslave MySQL servers replicating writes made to a master MySQL server. Itis important to understand the issues associated with this setup if youwant to write code destined for Wikipedia.It 's often the case that the best algorithm to use for a given taskdepends on whether or not replication is in use. Due to our unabashedWikipedia-centrism, we often just use the replication-friendly version, but if you like, you can use wfGetLB() ->getServerCount() > 1 tocheck to see if replication is in use.===Lag===Lag primarily occurs when large write queries are sent to the master.Writes on the master are executed in parallel, but they are executed inserial when they are replicated to the slaves. The master writes thequery to the binlog when the transaction is committed. The slaves pollthe binlog and start executing the query as soon as it appears. They canservice reads while they are performing a write query, but will not readanything more from the binlog and thus will perform no more writes. Thismeans that if the write query runs for a long time, the slaves will lagbehind the master for the time it takes for the write query to complete.Lag can be exacerbated by high read load. MediaWiki 's load balancer willstop sending reads to a slave when it is lagged by more than 30 seconds.If the load ratios are set incorrectly, or if there is too much loadgenerally, this may lead to a slave permanently hovering around 30seconds lag.If all slaves are lagged by more than 30 seconds, MediaWiki will stopwriting to the database. All edits and other write operations will berefused, with an error returned to the user. This gives the slaves achance to catch up. Before we had this mechanism, the slaves wouldregularly lag by several minutes, making review of recent editsdifficult.In addition to this, MediaWiki attempts to ensure that the user seesevents occurring on the wiki in chronological order. A few seconds of lagcan be tolerated, as long as the user sees a consistent picture fromsubsequent requests. This is done by saving the master binlog positionin the session, and then at the start of each request, waiting for theslave to catch up to that position before doing any reads from it. Ifthis wait times out, reads are allowed anyway, but the request isconsidered to be in "lagged slave mode". Lagged slave mode can bechecked by calling wfGetLB() ->getLaggedSlaveMode(). The onlypractical consequence at present is a warning displayed in the pagefooter.===Lag avoidance===To avoid excessive lag, queries which write large numbers of rows shouldbe split up, generally to write one row at a time. Multi-row INSERT ...SELECT queries are the worst offenders should be avoided altogether.Instead do the select first and then the insert.===Working with lag===Despite our best efforts, it 's not practical to guarantee a low-lagenvironment. Lag will usually be less than one second, but mayoccasionally be up to 30 seconds. For scalability, it 's very importantto keep load on the master low, so simply sending all your queries tothe master is not the answer. So when you have a genuine need forup-to-date data, the following approach is advised:1) Do a quick query to the master for a sequence number or timestamp 2) Run the full query on the slave and check if it matches the data you gotfrom the master 3) If it doesn 't, run the full query on the masterTo avoid swamping the master every time the slaves lag, use of thisapproach should be kept to a minimum. In most cases you should just readfrom the slave and let the user deal with the delay.------------------------------------------------------------------------ Lock contention------------------------------------------------------------------------Due to the high write rate on Wikipedia(and some other wikis), MediaWiki developers need to be very careful to structure their writesto avoid long-lasting locks. By default, MediaWiki opens a transactionat the first query, and commits it before the output is sent. Locks willbe held from the time when the query is done until the commit. So youcan reduce lock time by doing as much processing as possible before youdo your write queries.Often this approach is not good enough, and it becomes necessary toenclose small groups of queries in their own transaction. Use thefollowing syntax:$dbw=wfGetDB(DB_MASTER
doPopulateCategory( $begin, $maxlag, $throttle, $force)
Definition: populateCategory.php:68
& wfGetDB( $db, $groups=array(), $wiki=false)
Get a Database object.
Definition: GlobalFunctions.php:3706
addOption( $name, $description, $required=false, $withArg=false, $shortName=false)
Add a parameter to the script.
Definition: Maintenance.php:169
Definition: maintenance.txt:50
Abstract maintenance class for quickly writing and churning out maintenance scripts with minimal effo...
Definition: maintenance.txt:39
Definition: moveToExternal.php:24
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 then executing the whole list after the page is displayed We don t do anything smart like collating updates to the same table or such because the list is almost always going to have just one item on if so it s not worth the trouble Since there is a job queue in the jobs table
Definition: deferred.txt:11
Definition: populateCategory.php:34
the array() calling protocol came about after MediaWiki 1.4rc1.
List of Api Query prop modules.
Definition: populateCategory.php:130
Do the actual work.
Definition: populateCategory.php:60
wfWaitForSlaves( $maxLag=false, $wiki=false, $cluster=false)
Modern version of wfWaitForSlaves().
Definition: GlobalFunctions.php:3851
</td >< td > &</td >< td > t want your writing to be edited mercilessly and redistributed at will
Definition: All_system_messages.txt:914
Allows to change the fields on the form that will be generated $name
Definition: hooks.txt:336
We ve cleaned up the code here by removing clumps of infrequently used code and moving them off somewhere else It s much easier for someone working with this code to see what s _really_ going and make changes or fix bugs In we can take all the code that deals with the little used title reversing options(say) and put it in one place. Instead of having little title-reversing if-blocks spread all over the codebase in showAnArticle
=Architecture==Two class hierarchies are used to provide the functionality associated with the different content models:*Content interface(and AbstractContent base class) define functionality that acts on the concrete content of a page, and *ContentHandler base class provides functionality specific to a content model, but not acting on concrete content. The most important function of ContentHandler is to act as a factory for the appropriate implementation of Content. These Content objects are to be used by MediaWiki everywhere, instead of passing page content around as text. All manipulation and analysis of page content must be done via the appropriate methods of the Content object. For each content model, a subclass of ContentHandler has to be registered with $wgContentHandlers. The ContentHandler object for a given content model can be obtained using ContentHandler::getForModelID($id). Also Title, WikiPage and Revision now have getContentHandler() methods for convenience. ContentHandler objects are singletons that provide functionality specific to the content type, but not directly acting on the content of some page. ContentHandler::makeEmptyContent() and ContentHandler::unserializeContent() can be used to create a Content object of the appropriate type. However, it is recommended to instead use WikiPage::getContent() resp. Revision::getContent() to get a page 's content as a Content object. These two methods should be the ONLY way in which page content is accessed. Another important function of ContentHandler objects is to define custom action handlers for a content model, see ContentHandler::getActionOverrides(). This is similar to what WikiPage::getActionOverrides() was already doing.==Serialization==With the ContentHandler facility, page content no longer has to be text based. Objects implementing the Content interface are used to represent and handle the content internally. For storage and data exchange, each content model supports at least one serialization format via ContentHandler::serializeContent($content). The list of supported formats for a given content model can be accessed using ContentHandler::getSupportedFormats(). Content serialization formats are identified using MIME type like strings. The following formats are built in:*text/x-wiki - wikitext *text/javascript - for js pages *text/css - for css pages *text/plain - for future use, e.g. with plain text messages. *text/html - for future use, e.g. with plain html messages. *application/vnd.php.serialized - for future use with the api and for extensions *application/json - for future use with the api, and for use by extensions *application/xml - for future use with the api, and for use by extensions In PHP, use the corresponding CONTENT_FORMAT_XXX constant. Note that when using the API to access page content, especially action=edit, action=parse and action=query &prop=revisions, the model and format of the content should always be handled explicitly. Without that information, interpretation of the provided content is not reliable. The same applies to XML dumps generated via maintenance/dumpBackup.php or Special:Export. Also note that the API will provide encapsulated, serialized content - so if the API was called with format=json, and contentformat is also json(or rather, application/json), the page content is represented as a string containing an escaped json structure. Extensions that use JSON to serialize some types of page content may provide specialized API modules that allow access to that content in a more natural form.==Compatibility==The ContentHandler facility is introduced in a way that should allow all existing code to keep functioning at least for pages that contain wikitext or other text based content. However, a number of functions and hooks have been deprecated in favor of new versions that are aware of the page 's content model, and will now generate warnings when used. Most importantly, the following functions have been deprecated:*Revisions::getText() and Revisions::getRawText() is deprecated in favor Revisions::getContent() *WikiPage::getText() is deprecated in favor WikiPage::getContent() Also, the old Article::getContent()(which returns text) is superceded by Article::getContentObject(). However, both methods should be avoided since they do not provide clean access to the page 's actual content. For instance, they may return a system message for non-existing pages. Use WikiPage::getContent() instead. Code that relies on a textual representation of the page content should eventually be rewritten. However, ContentHandler::getContentText() provides a stop-gap that can be used to get text for a page. Its behavior is controlled by $wgContentHandlerTextFallback it
Definition: contenthandler.txt:107
getOption( $name, $default=null)
Get an option, or return the default.
Definition: Maintenance.php:191
Prior to maintenance scripts were a hodgepodge of code that had no cohesion or formal method of action Beginning in
Definition: maintenance.txt:1
We ve cleaned up the code here by removing clumps of infrequently used code and moving them off somewhere else It s much easier for someone working with this code to see what s _really_ going on
Definition: hooks.txt:86
Default constructor.
Definition: populateCategory.php:36
output( $out, $channel=null)
Throw some output to the user.
Definition: Maintenance.php:314
static newFromName( $name)
Factory function.
Definition: Category.php:114