MediaWiki  REL1_31
populateCategory.php
Go to the documentation of this file.
1 <?php
25 require_once __DIR__ . '/Maintenance.php';
26 
33 
34  const REPORTING_INTERVAL = 1000;
35 
36  public function __construct() {
37  parent::__construct();
38  $this->addDescription(
39  <<<TEXT
40 This script will populate the category table, added in MediaWiki 1.13. It will
41 print out progress indicators every 1000 categories it adds to the table. The
42 script is perfectly safe to run on large, live wikis, and running it multiple
43 times is harmless. You may want to use the throttling options if it's causing
44 too much load; they will not affect correctness.
45 
46 If the script is stopped and later resumed, you can use the --begin option with
47 the last printed progress indicator to pick up where you left off. This is
48 safe, because any newly-added categories before this cutoff will have been
49 added after the software update and so will be populated anyway.
50 
51 When the script has finished, it will make a note of this in the database, and
52 will not run again without the --force option.
53 TEXT
54  );
55 
56  $this->addOption(
57  'begin',
58  'Only do categories whose names are alphabetically after the provided name',
59  false,
60  true
61  );
62  $this->addOption(
63  'throttle',
64  'Wait this many milliseconds after each category. Default: 0',
65  false,
66  true
67  );
68  $this->addOption( 'force', 'Run regardless of whether the database says it\'s been run already' );
69  }
70 
71  public function execute() {
72  $begin = $this->getOption( 'begin', '' );
73  $throttle = $this->getOption( 'throttle', 0 );
74  $force = $this->hasOption( 'force' );
75 
76  $dbw = $this->getDB( DB_MASTER );
77 
78  if ( !$force ) {
79  $row = $dbw->selectRow(
80  'updatelog',
81  '1',
82  [ 'ul_key' => 'populate category' ],
83  __METHOD__
84  );
85  if ( $row ) {
86  $this->output( "Category table already populated. Use php " .
87  "maintenance/populateCategory.php\n--force from the command line " .
88  "to override.\n" );
89 
90  return true;
91  }
92  }
93 
94  $throttle = intval( $throttle );
95  if ( $begin !== '' ) {
96  $where = 'cl_to > ' . $dbw->addQuotes( $begin );
97  } else {
98  $where = null;
99  }
100  $i = 0;
101 
102  while ( true ) {
103  # Find which category to update
104  $row = $dbw->selectRow(
105  'categorylinks',
106  'cl_to',
107  $where,
108  __METHOD__,
109  [
110  'ORDER BY' => 'cl_to'
111  ]
112  );
113  if ( !$row ) {
114  # Done, hopefully.
115  break;
116  }
117  $name = $row->cl_to;
118  $where = 'cl_to > ' . $dbw->addQuotes( $name );
119 
120  # Use the row to update the category count
121  $cat = Category::newFromName( $name );
122  if ( !is_object( $cat ) ) {
123  $this->output( "The category named $name is not valid?!\n" );
124  } else {
125  $cat->refreshCounts();
126  }
127 
128  ++$i;
129  if ( !( $i % self::REPORTING_INTERVAL ) ) {
130  $this->output( "$name\n" );
131  wfWaitForSlaves();
132  }
133  usleep( $throttle * 1000 );
134  }
135 
136  if ( $dbw->insert(
137  'updatelog',
138  [ 'ul_key' => 'populate category' ],
139  __METHOD__,
140  'IGNORE'
141  ) ) {
142  $this->output( "Category population complete.\n" );
143 
144  return true;
145  } else {
146  $this->output( "Could not insert category population row.\n" );
147 
148  return false;
149  }
150  }
151 }
152 
154 require_once RUN_MAINTENANCE_IF_MAIN;
use
Apache License January AND DISTRIBUTION Definitions License shall mean the terms and conditions for use
Definition: APACHE-LICENSE-2.0.txt:10
PopulateCategory
Maintenance script to populate the category table.
Definition: populateCategory.php:32
names
within a display generated by the Derivative if and wherever such third party notices normally appear The contents of the NOTICE file are for informational purposes only and do not modify the License You may add Your own attribution notices within Derivative Works that You alongside or as an addendum to the NOTICE text from the provided that such additional attribution notices cannot be construed as modifying the License You may add Your own copyright statement to Your modifications and may provide additional or different license terms and conditions for or distribution of Your or for any such Derivative Works as a provided Your and distribution of the Work otherwise complies with the conditions stated in this License Submission of Contributions Unless You explicitly state any Contribution intentionally submitted for inclusion in the Work by You to the Licensor shall be under the terms and conditions of this without any additional terms or conditions Notwithstanding the nothing herein shall supersede or modify the terms of any separate license agreement you may have executed with Licensor regarding such Contributions Trademarks This License does not grant permission to use the trade names
Definition: APACHE-LICENSE-2.0.txt:140
is
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
Maintenance\addDescription
addDescription( $text)
Set the description text.
Definition: Maintenance.php:291
RUN_MAINTENANCE_IF_MAIN
require_once RUN_MAINTENANCE_IF_MAIN
Definition: maintenance.txt:50
database
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 database
Definition: design.txt:13
Maintenance
Abstract maintenance class for quickly writing and churning out maintenance scripts with minimal effo...
Definition: maintenance.txt:39
wfWaitForSlaves
wfWaitForSlaves( $ifWritesSince=null, $wiki=false, $cluster=false, $timeout=null)
Waits for the replica DBs to catch up to the master position.
Definition: GlobalFunctions.php:2966
php
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
Definition: injection.txt:37
REPORTING_INTERVAL
const REPORTING_INTERVAL
Definition: moveToExternal.php:24
table
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:16
MediaWiki
A helper class for throttling authentication attempts.
PopulateCategory\REPORTING_INTERVAL
const REPORTING_INTERVAL
Definition: populateCategory.php:34
$maintClass
$maintClass
Definition: populateCategory.php:153
DB_MASTER
const DB_MASTER
Definition: defines.php:26
PopulateCategory\execute
execute()
Do the actual work.
Definition: populateCategory.php:71
will
</td >< td > &</td >< td > t want your writing to be edited mercilessly and redistributed at will
Definition: All_system_messages.txt:914
it
=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() 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:104
options
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
and
and(b) You must cause any modified files to carry prominent notices stating that You changed the files
begin
$dbw begin(__METHOD__)
print
print
Definition: opensearch_desc.php:46
$name
Allows to change the fields on the form that will be generated $name
Definition: hooks.txt:302
Maintenance\getOption
getOption( $name, $default=null)
Get an option, or return the default.
Definition: Maintenance.php:254
on
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
are
The ContentHandler facility adds support for arbitrary content types on wiki instead of relying on wikitext for everything It was introduced in MediaWiki Each kind of and so on Built in content types are
Definition: contenthandler.txt:9
Maintenance\getDB
getDB( $db, $groups=[], $wiki=false)
Returns a database to be used by current maintenance script.
Definition: Maintenance.php:1309
PopulateCategory\__construct
__construct()
Default constructor.
Definition: populateCategory.php:36
Maintenance\output
output( $out, $channel=null)
Throw some output to the user.
Definition: Maintenance.php:388
in
null for the wiki Added in
Definition: hooks.txt:1591
of
globals txt Globals are evil The original MediaWiki code relied on globals for processing context far too often MediaWiki development since then has been a story of slowly moving context out of global variables and into objects Storing processing context in object member variables allows those objects to be reused in a much more flexible way Consider the elegance of
database rows
Definition: globals.txt:10
name
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 name
Definition: design.txt:12
class
you have access to all of the normal MediaWiki so you can get a DB use the etc For full docs on the Maintenance class
Definition: maintenance.txt:56
Category\newFromName
static newFromName( $name)
Factory function.
Definition: Category.php:126
Maintenance\hasOption
hasOption( $name)
Checks to see if a particular param exists.
Definition: Maintenance.php:240