MediaWiki  1.28.0
ParserCache.php
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1 <?php
28 class ParserCache {
30  private $mMemc;
36  public static function singleton() {
37  static $instance;
38  if ( !isset( $instance ) ) {
40  $instance = new ParserCache( $parserMemc );
41  }
42  return $instance;
43  }
44 
54  protected function __construct( BagOStuff $memCached ) {
55  $this->mMemc = $memCached;
56  }
57 
63  protected function getParserOutputKey( $article, $hash ) {
65 
66  // idhash seem to mean 'page id' + 'rendering hash' (r3710)
67  $pageid = $article->getId();
68  $renderkey = (int)( $wgRequest->getVal( 'action' ) == 'render' );
69 
70  $key = wfMemcKey( 'pcache', 'idhash', "{$pageid}-{$renderkey}!{$hash}" );
71  return $key;
72  }
73 
78  protected function getOptionsKey( $page ) {
79  return wfMemcKey( 'pcache', 'idoptions', $page->getId() );
80  }
81 
86  public function deleteOptionsKey( $page ) {
87  $this->mMemc->delete( $this->getOptionsKey( $page ) );
88  }
89 
104  public function getETag( $article, $popts ) {
105  return 'W/"' . $this->getParserOutputKey( $article,
106  $popts->optionsHash( ParserOptions::legacyOptions(), $article->getTitle() ) ) .
107  "--" . $article->getTouched() . '"';
108  }
109 
116  public function getDirty( $article, $popts ) {
117  $value = $this->get( $article, $popts, true );
118  return is_object( $value ) ? $value : false;
119  }
120 
140  public function getKey( $article, $popts, $useOutdated = true ) {
142 
143  if ( $popts instanceof User ) {
144  wfWarn( "Use of outdated prototype ParserCache::getKey( &\$article, &\$user )\n" );
145  $popts = ParserOptions::newFromUser( $popts );
146  }
147 
148  // Determine the options which affect this article
149  $casToken = null;
150  $optionsKey = $this->mMemc->get(
151  $this->getOptionsKey( $article ), $casToken, BagOStuff::READ_VERIFIED );
152  if ( $optionsKey instanceof CacheTime ) {
153  if ( !$useOutdated && $optionsKey->expired( $article->getTouched() ) ) {
154  wfIncrStats( "pcache.miss.expired" );
155  $cacheTime = $optionsKey->getCacheTime();
156  wfDebugLog( "ParserCache",
157  "Parser options key expired, touched " . $article->getTouched()
158  . ", epoch $wgCacheEpoch, cached $cacheTime\n" );
159  return false;
160  } elseif ( !$useOutdated && $optionsKey->isDifferentRevision( $article->getLatest() ) ) {
161  wfIncrStats( "pcache.miss.revid" );
162  $revId = $article->getLatest();
163  $cachedRevId = $optionsKey->getCacheRevisionId();
164  wfDebugLog( "ParserCache",
165  "ParserOutput key is for an old revision, latest $revId, cached $cachedRevId\n"
166  );
167  return false;
168  }
169 
170  // $optionsKey->mUsedOptions is set by save() by calling ParserOutput::getUsedOptions()
171  $usedOptions = $optionsKey->mUsedOptions;
172  wfDebug( "Parser cache options found.\n" );
173  } else {
174  if ( !$useOutdated ) {
175  return false;
176  }
177  $usedOptions = ParserOptions::legacyOptions();
178  }
179 
180  return $this->getParserOutputKey(
181  $article,
182  $popts->optionsHash( $usedOptions, $article->getTitle() )
183  );
184  }
185 
196  public function get( $article, $popts, $useOutdated = false ) {
198 
199  $canCache = $article->checkTouched();
200  if ( !$canCache ) {
201  // It's a redirect now
202  return false;
203  }
204 
205  $touched = $article->getTouched();
206 
207  $parserOutputKey = $this->getKey( $article, $popts, $useOutdated );
208  if ( $parserOutputKey === false ) {
209  wfIncrStats( 'pcache.miss.absent' );
210  return false;
211  }
212 
213  $casToken = null;
215  $value = $this->mMemc->get( $parserOutputKey, $casToken, BagOStuff::READ_VERIFIED );
216  if ( !$value ) {
217  wfDebug( "ParserOutput cache miss.\n" );
218  wfIncrStats( "pcache.miss.absent" );
219  return false;
220  }
221 
222  wfDebug( "ParserOutput cache found.\n" );
223 
224  // The edit section preference may not be the appropiate one in
225  // the ParserOutput, as we are not storing it in the parsercache
226  // key. Force it here. See bug 31445.
227  $value->setEditSectionTokens( $popts->getEditSection() );
228 
229  $wikiPage = method_exists( $article, 'getPage' )
230  ? $article->getPage()
231  : $article;
232 
233  if ( !$useOutdated && $value->expired( $touched ) ) {
234  wfIncrStats( "pcache.miss.expired" );
235  $cacheTime = $value->getCacheTime();
236  wfDebugLog( "ParserCache",
237  "ParserOutput key expired, touched $touched, "
238  . "epoch $wgCacheEpoch, cached $cacheTime\n" );
239  $value = false;
240  } elseif ( !$useOutdated && $value->isDifferentRevision( $article->getLatest() ) ) {
241  wfIncrStats( "pcache.miss.revid" );
242  $revId = $article->getLatest();
243  $cachedRevId = $value->getCacheRevisionId();
244  wfDebugLog( "ParserCache",
245  "ParserOutput key is for an old revision, latest $revId, cached $cachedRevId\n"
246  );
247  $value = false;
248  } elseif (
249  Hooks::run( 'RejectParserCacheValue', [ $value, $wikiPage, $popts ] ) === false
250  ) {
251  wfIncrStats( 'pcache.miss.rejected' );
252  wfDebugLog( "ParserCache",
253  "ParserOutput key valid, but rejected by RejectParserCacheValue hook handler.\n"
254  );
255  $value = false;
256  } else {
257  wfIncrStats( "pcache.hit" );
258  }
259 
260  return $value;
261  }
262 
270  public function save( $parserOutput, $page, $popts, $cacheTime = null, $revId = null ) {
271  $expire = $parserOutput->getCacheExpiry();
272  if ( $expire > 0 && !$this->mMemc instanceof EmptyBagOStuff ) {
273  $cacheTime = $cacheTime ?: wfTimestampNow();
274  if ( !$revId ) {
275  $revision = $page->getRevision();
276  $revId = $revision ? $revision->getId() : null;
277  }
278 
279  $optionsKey = new CacheTime;
280  $optionsKey->mUsedOptions = $parserOutput->getUsedOptions();
281  $optionsKey->updateCacheExpiry( $expire );
282 
283  $optionsKey->setCacheTime( $cacheTime );
284  $parserOutput->setCacheTime( $cacheTime );
285  $optionsKey->setCacheRevisionId( $revId );
286  $parserOutput->setCacheRevisionId( $revId );
287 
288  $parserOutputKey = $this->getParserOutputKey( $page,
289  $popts->optionsHash( $optionsKey->mUsedOptions, $page->getTitle() ) );
290 
291  // Save the timestamp so that we don't have to load the revision row on view
292  $parserOutput->setTimestamp( $page->getTimestamp() );
293 
294  $msg = "Saved in parser cache with key $parserOutputKey" .
295  " and timestamp $cacheTime" .
296  " and revision id $revId" .
297  "\n";
298 
299  $parserOutput->mText .= "\n<!-- $msg -->\n";
300  wfDebug( $msg );
301 
302  // Save the parser output
303  $this->mMemc->set( $parserOutputKey, $parserOutput, $expire );
304 
305  // ...and its pointer
306  $this->mMemc->set( $this->getOptionsKey( $page ), $optionsKey, $expire );
307 
308  Hooks::run(
309  'ParserCacheSaveComplete',
310  [ $this, $parserOutput, $page->getTitle(), $popts, $revId ]
311  );
312  } elseif ( $expire <= 0 ) {
313  wfDebug( "Parser output was marked as uncacheable and has not been saved.\n" );
314  }
315  }
316 }
static legacyOptions()
Returns the full array of options that would have been used by in 1.16.
processing should stop and the error should be shown to the user * false
Definition: hooks.txt:189
if(!$wgDBerrorLogTZ) $wgRequest
Definition: Setup.php:664
save($parserOutput, $page, $popts, $cacheTime=null, $revId=null)
Using a hook running we can avoid having all this option specific stuff in our mainline code Using the function array $article
Definition: hooks.txt:78
$value
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 as the deletion has already been partly carried out by this point or something similar the user will be unable to create the tag set and then return false from the hook function Ensure you consume the ChangeTagAfterDelete hook to carry out custom deletion actions as context called by AbstractContent::getParserOutput May be used to override the normal model specific rendering of page content as context $revId
Definition: hooks.txt:1046
Parser cache specific expiry check.
Definition: CacheTime.php:29
getParserOutputKey($article, $hash)
Definition: ParserCache.php:63
when a variable name is used in a it is silently declared as a new local masking the global
Definition: design.txt:93
static newFromUser($user)
Get a ParserOptions object from a given user.
wfDebug($text, $dest= 'all', array $context=[])
Sends a line to the debug log if enabled or, optionally, to a comment in output.
null means default in associative array with keys and values unescaped Should be merged with default with a value of false meaning to suppress the attribute in associative array with keys and values unescaped noclasses just before the function returns a value If you return true
Definition: hooks.txt:1936
wfDebugLog($logGroup, $text, $dest= 'all', array $context=[])
Send a line to a supplementary debug log file, if configured, or main debug log if not...
getETag($article, $popts)
Provides an E-Tag suitable for the whole page.
getDirty($article, $popts)
Retrieve the ParserOutput from ParserCache, even if it's outdated.
const READ_VERIFIED
Definition: BagOStuff.php:84
wfWarn($msg, $callerOffset=1, $level=E_USER_NOTICE)
Send a warning either to the debug log or in a PHP error depending on $wgDevelopmentWarnings.
getKey($article, $popts, $useOutdated=true)
Generates a key for caching the given article considering the given parser options.
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 as the deletion has already been partly carried out by this point or something similar the user will be unable to create the tag set and then return false from the hook function Ensure you consume the ChangeTagAfterDelete hook to carry out custom deletion actions as context $parserOutput
Definition: hooks.txt:1046
BagOStuff $mMemc
Definition: ParserCache.php:30
controlled by $wgMainCacheType * $parserMemc
Definition: memcached.txt:78
wfTimestampNow()
Convenience function; returns MediaWiki timestamp for the present time.
wfIncrStats($key, $count=1)
Increment a statistics counter.
A BagOStuff object with no objects in it.
static run($event, array $args=[], $deprecatedVersion=null)
Call hook functions defined in Hooks::register and $wgHooks.
Definition: Hooks.php:131
__construct(BagOStuff $memCached)
Setup a cache pathway with a given back-end storage mechanism.
Definition: ParserCache.php:54
static singleton()
Get an instance of this object.
Definition: ParserCache.php:36
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 $wgServiceWiringFiles lists includes ServiceWiring php
Definition: injection.txt:35
deleteOptionsKey($page)
Definition: ParserCache.php:86
wfMemcKey()
Make a cache key for the local wiki.
getOptionsKey($page)
Definition: ParserCache.php:78
$wgCacheEpoch
Set this to current time to invalidate all prior cached pages.
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 $page
Definition: hooks.txt:2491