MediaWiki 1.30.2

[autoinstallsdev/mediawiki.git] / includes / parser / CacheTime.php

diff --git a/includes/parser/CacheTime.php b/includes/parser/CacheTime.php
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+<?php
+/**
+ * Parser cache specific expiry check.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Parser
+ */
+
+/**
+ * Parser cache specific expiry check.
+ *
+ * @ingroup Parser
+ */
+class CacheTime {
+       /** @var array|bool ParserOptions which have been taken into account to
+        * produce output or false if not available.
+        */
+       public $mUsedOptions;
+
+       # Compatibility check
+       public $mVersion = Parser::VERSION;
+
+       # Time when this object was generated, or -1 for uncacheable. Used in ParserCache.
+       public $mCacheTime = '';
+
+       # Seconds after which the object should expire, use 0 for uncacheable. Used in ParserCache.
+       public $mCacheExpiry = null;
+
+       # Revision ID that was parsed
+       public $mCacheRevisionId = null;
+
+       /**
+        * @return string TS_MW timestamp
+        */
+       public function getCacheTime() {
+               return wfTimestamp( TS_MW, $this->mCacheTime );
+       }
+
+       /**
+        * setCacheTime() sets the timestamp expressing when the page has been rendered.
+        * This does not control expiry, see updateCacheExpiry() for that!
+        * @param string $t TS_MW timestamp
+        * @return string
+        */
+       public function setCacheTime( $t ) {
+               return wfSetVar( $this->mCacheTime, $t );
+       }
+
+       /**
+        * @since 1.23
+        * @return int|null Revision id, if any was set
+        */
+       public function getCacheRevisionId() {
+               return $this->mCacheRevisionId;
+       }
+
+       /**
+        * @since 1.23
+        * @param int $id Revision id
+        */
+       public function setCacheRevisionId( $id ) {
+               $this->mCacheRevisionId = $id;
+       }
+
+       /**
+        * Sets the number of seconds after which this object should expire.
+        *
+        * This value is used with the ParserCache.
+        * If called with a value greater than the value provided at any previous call,
+        * the new call has no effect. The value returned by getCacheExpiry is smaller
+        * or equal to the smallest number that was provided as an argument to
+        * updateCacheExpiry().
+        *
+        * Avoid using 0 if at all possible. Consider JavaScript for highly dynamic content.
+        *
+        * @param int $seconds
+        */
+       public function updateCacheExpiry( $seconds ) {
+               $seconds = (int)$seconds;
+
+               if ( $this->mCacheExpiry === null || $this->mCacheExpiry > $seconds ) {
+                       $this->mCacheExpiry = $seconds;
+               }
+       }
+
+       /**
+        * Returns the number of seconds after which this object should expire.
+        * This method is used by ParserCache to determine how long the ParserOutput can be cached.
+        * The timestamp of expiry can be calculated by adding getCacheExpiry() to getCacheTime().
+        * The value returned by getCacheExpiry is smaller or equal to the smallest number
+        * that was provided to a call of updateCacheExpiry(), and smaller or equal to the
+        * value of $wgParserCacheExpireTime.
+        * @return int|mixed|null
+        */
+       public function getCacheExpiry() {
+               global $wgParserCacheExpireTime;
+
+               if ( $this->mCacheTime < 0 ) {
+                       return 0;
+               } // old-style marker for "not cacheable"
+
+               $expire = $this->mCacheExpiry;
+
+               if ( $expire === null ) {
+                       $expire = $wgParserCacheExpireTime;
+               } else {
+                       $expire = min( $expire, $wgParserCacheExpireTime );
+               }
+
+               if ( $expire <= 0 ) {
+                       return 0; // not cacheable
+               } else {
+                       return $expire;
+               }
+       }
+
+       /**
+        * @return bool
+        */
+       public function isCacheable() {
+               return $this->getCacheExpiry() > 0;
+       }
+
+       /**
+        * Return true if this cached output object predates the global or
+        * per-article cache invalidation timestamps, or if it comes from
+        * an incompatible older version.
+        *
+        * @param string $touched The affected article's last touched timestamp
+        * @return bool
+        */
+       public function expired( $touched ) {
+               global $wgCacheEpoch;
+
+               return !$this->isCacheable() // parser says it's uncacheable
+                       || $this->getCacheTime() < $touched
+                       || $this->getCacheTime() <= $wgCacheEpoch
+                       || $this->getCacheTime() <
+                               wfTimestamp( TS_MW, time() - $this->getCacheExpiry() ) // expiry period has passed
+                       || !isset( $this->mVersion )
+                       || version_compare( $this->mVersion, Parser::VERSION, "lt" );
+       }
+
+       /**
+        * Return true if this cached output object is for a different revision of
+        * the page.
+        *
+        * @todo We always return false if $this->getCacheRevisionId() is null;
+        * this prevents invalidating the whole parser cache when this change is
+        * deployed. Someday that should probably be changed.
+        *
+        * @since 1.23
+        * @param int $id The affected article's current revision id
+        * @return bool
+        */
+       public function isDifferentRevision( $id ) {
+               $cached = $this->getCacheRevisionId();
+               return $cached !== null && $id !== $cached;
+       }
+}