Move CacheHelper to includes/cache/ folder

Change-Id: I13c9cf1be7fe0d436ea1a5d23f162abac7d97a29

1 files changed, 0 insertions, 386 deletions

diff --git a/includes/CacheHelper.php b/includes/CacheHelper.php
deleted file mode 100644
index 695eac3a05ab..000000000000
--- a/includes/CacheHelper.php
+++ /dev/null
@@ -1,386 +0,0 @@
-<?php
-/**
- * Cache of various elements in a single cache entry.
- *
- * 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
- * @license GNU GPL v2 or later
- * @author Jeroen De Dauw < jeroendedauw@gmail.com >
- */
-
-/**
- * Interface for all classes implementing CacheHelper functionality.
- *
- * @since 1.20
- */
-interface ICacheHelper {
-	/**
-	 * Sets if the cache should be enabled or not.
-	 *
-	 * @since 1.20
-	 * @param bool $cacheEnabled
-	 */
-	function setCacheEnabled( $cacheEnabled );
-
-	/**
-	 * Initializes the caching.
-	 * Should be called before the first time anything is added via addCachedHTML.
-	 *
-	 * @since 1.20
-	 *
-	 * @param int|null $cacheExpiry Sets the cache expiry, either ttl in seconds or unix timestamp.
-	 * @param bool|null $cacheEnabled Sets if the cache should be enabled or not.
-	 */
-	function startCache( $cacheExpiry = null, $cacheEnabled = null );
-
-	/**
-	 * Get a cached value if available or compute it if not and then cache it if possible.
-	 * The provided $computeFunction is only called when the computation needs to happen
-	 * and should return a result value. $args are arguments that will be passed to the
-	 * compute function when called.
-	 *
-	 * @since 1.20
-	 *
-	 * @param {function} $computeFunction
-	 * @param array|mixed $args
-	 * @param string|null $key
-	 *
-	 * @return mixed
-	 */
-	function getCachedValue( $computeFunction, $args = array(), $key = null );
-
-	/**
-	 * Saves the HTML to the cache in case it got recomputed.
-	 * Should be called after the last time anything is added via addCachedHTML.
-	 *
-	 * @since 1.20
-	 */
-	function saveCache();
-
-	/**
-	 * Sets the time to live for the cache, in seconds or a unix timestamp
-	 * indicating the point of expiry...
-	 *
-	 * @since 1.20
-	 *
-	 * @param int $cacheExpiry
-	 */
-	function setExpiry( $cacheExpiry );
-}
-
-/**
- * Helper class for caching various elements in a single cache entry.
- *
- * To get a cached value or compute it, use getCachedValue like this:
- * $this->getCachedValue( $callback );
- *
- * To add HTML that should be cached, use addCachedHTML like this:
- * $this->addCachedHTML( $callback );
- *
- * The callback function is only called when needed, so do all your expensive
- * computations here. This function should returns the HTML to be cached.
- * It should not add anything to the PageOutput object!
- *
- * Before the first addCachedHTML call, you should call $this->startCache();
- * After adding the last HTML that should be cached, call $this->saveCache();
- *
- * @since 1.20
- */
-class CacheHelper implements ICacheHelper {
-	/**
-	 * The time to live for the cache, in seconds or a unix timestamp indicating the point of expiry.
-	 *
-	 * @since 1.20
-	 * @var int
-	 */
-	protected $cacheExpiry = 3600;
-
-	/**
-	 * List of HTML chunks to be cached (if !hasCached) or that where cached (of hasCached).
-	 * If not cached already, then the newly computed chunks are added here,
-	 * if it as cached already, chunks are removed from this list as they are needed.
-	 *
-	 * @since 1.20
-	 * @var array
-	 */
-	protected $cachedChunks;
-
-	/**
-	 * Indicates if the to be cached content was already cached.
-	 * Null if this information is not available yet.
-	 *
-	 * @since 1.20
-	 * @var bool|null
-	 */
-	protected $hasCached = null;
-
-	/**
-	 * If the cache is enabled or not.
-	 *
-	 * @since 1.20
-	 * @var bool
-	 */
-	protected $cacheEnabled = true;
-
-	/**
-	 * Function that gets called when initialization is done.
-	 *
-	 * @since 1.20
-	 * @var callable
-	 */
-	protected $onInitHandler = false;
-
-	/**
-	 * Elements to build a cache key with.
-	 *
-	 * @since 1.20
-	 * @var array
-	 */
-	protected $cacheKey = array();
-
-	/**
-	 * Sets if the cache should be enabled or not.
-	 *
-	 * @since 1.20
-	 * @param bool $cacheEnabled
-	 */
-	public function setCacheEnabled( $cacheEnabled ) {
-		$this->cacheEnabled = $cacheEnabled;
-	}
-
-	/**
-	 * Initializes the caching.
-	 * Should be called before the first time anything is added via addCachedHTML.
-	 *
-	 * @since 1.20
-	 *
-	 * @param int|null $cacheExpiry Sets the cache expiry, either ttl in seconds or unix timestamp.
-	 * @param bool|null $cacheEnabled Sets if the cache should be enabled or not.
-	 */
-	public function startCache( $cacheExpiry = null, $cacheEnabled = null ) {
-		if ( is_null( $this->hasCached ) ) {
-			if ( !is_null( $cacheExpiry ) ) {
-				$this->cacheExpiry = $cacheExpiry;
-			}
-
-			if ( !is_null( $cacheEnabled ) ) {
-				$this->setCacheEnabled( $cacheEnabled );
-			}
-
-			$this->initCaching();
-		}
-	}
-
-	/**
-	 * Returns a message that notifies the user he/she is looking at
-	 * a cached version of the page, including a refresh link.
-	 *
-	 * @since 1.20
-	 *
-	 * @param IContextSource $context
-	 * @param bool $includePurgeLink
-	 *
-	 * @return string
-	 */
-	public function getCachedNotice( IContextSource $context, $includePurgeLink = true ) {
-		if ( $this->cacheExpiry < 86400 * 3650 ) {
-			$message = $context->msg(
-				'cachedspecial-viewing-cached-ttl',
-				$context->getLanguage()->formatDuration( $this->cacheExpiry )
-			)->escaped();
-		} else {
-			$message = $context->msg(
-				'cachedspecial-viewing-cached-ts'
-			)->escaped();
-		}
-
-		if ( $includePurgeLink ) {
-			$refreshArgs = $context->getRequest()->getQueryValues();
-			unset( $refreshArgs['title'] );
-			$refreshArgs['action'] = 'purge';
-
-			$subPage = $context->getTitle()->getFullText();
-			$subPage = explode( '/', $subPage, 2 );
-			$subPage = count( $subPage ) > 1 ? $subPage[1] : false;
-
-			$message .= ' ' . Linker::link(
-				$context->getTitle( $subPage ),
-				$context->msg( 'cachedspecial-refresh-now' )->escaped(),
-				array(),
-				$refreshArgs
-			);
-		}
-
-		return $message;
-	}
-
-	/**
-	 * Initializes the caching if not already done so.
-	 * Should be called before any of the caching functionality is used.
-	 *
-	 * @since 1.20
-	 */
-	protected function initCaching() {
-		if ( $this->cacheEnabled && is_null( $this->hasCached ) ) {
-			$cachedChunks = wfGetCache( CACHE_ANYTHING )->get( $this->getCacheKeyString() );
-
-			$this->hasCached = is_array( $cachedChunks );
-			$this->cachedChunks = $this->hasCached ? $cachedChunks : array();
-
-			if ( $this->onInitHandler !== false ) {
-				call_user_func( $this->onInitHandler, $this->hasCached );
-			}
-		}
-	}
-
-	/**
-	 * Get a cached value if available or compute it if not and then cache it if possible.
-	 * The provided $computeFunction is only called when the computation needs to happen
-	 * and should return a result value. $args are arguments that will be passed to the
-	 * compute function when called.
-	 *
-	 * @since 1.20
-	 *
-	 * @param {function} $computeFunction
-	 * @param array|mixed $args
-	 * @param string|null $key
-	 *
-	 * @return mixed
-	 */
-	public function getCachedValue( $computeFunction, $args = array(), $key = null ) {
-		$this->initCaching();
-
-		if ( $this->cacheEnabled && $this->hasCached ) {
-			$value = null;
-
-			if ( is_null( $key ) ) {
-				$itemKey = array_keys( array_slice( $this->cachedChunks, 0, 1 ) );
-				$itemKey = array_shift( $itemKey );
-
-				if ( !is_integer( $itemKey ) ) {
-					wfWarn( "Attempted to get item with non-numeric key while " .
-						"the next item in the queue has a key ($itemKey) in " . __METHOD__ );
-				} elseif ( is_null( $itemKey ) ) {
-					wfWarn( "Attempted to get an item while the queue is empty in " . __METHOD__ );
-				} else {
-					$value = array_shift( $this->cachedChunks );
-				}
-			} else {
-				if ( array_key_exists( $key, $this->cachedChunks ) ) {
-					$value = $this->cachedChunks[$key];
-					unset( $this->cachedChunks[$key] );
-				} else {
-					wfWarn( "There is no item with key '$key' in this->cachedChunks in " . __METHOD__ );
-				}
-			}
-		} else {
-			if ( !is_array( $args ) ) {
-				$args = array( $args );
-			}
-
-			$value = call_user_func_array( $computeFunction, $args );
-
-			if ( $this->cacheEnabled ) {
-				if ( is_null( $key ) ) {
-					$this->cachedChunks[] = $value;
-				} else {
-					$this->cachedChunks[$key] = $value;
-				}
-			}
-		}
-
-		return $value;
-	}
-
-	/**
-	 * Saves the HTML to the cache in case it got recomputed.
-	 * Should be called after the last time anything is added via addCachedHTML.
-	 *
-	 * @since 1.20
-	 */
-	public function saveCache() {
-		if ( $this->cacheEnabled && $this->hasCached === false && !empty( $this->cachedChunks ) ) {
-			wfGetCache( CACHE_ANYTHING )->set(
-				$this->getCacheKeyString(),
-				$this->cachedChunks,
-				$this->cacheExpiry
-			);
-		}
-	}
-
-	/**
-	 * Sets the time to live for the cache, in seconds or a unix timestamp
-	 * indicating the point of expiry...
-	 *
-	 * @since 1.20
-	 *
-	 * @param int $cacheExpiry
-	 */
-	public function setExpiry( $cacheExpiry ) {
-		$this->cacheExpiry = $cacheExpiry;
-	}
-
-	/**
-	 * Returns the cache key to use to cache this page's HTML output.
-	 * Is constructed from the special page name and language code.
-	 *
-	 * @since 1.20
-	 *
-	 * @return string
-	 * @throws MWException
-	 */
-	protected function getCacheKeyString() {
-		if ( $this->cacheKey === array() ) {
-			throw new MWException( 'No cache key set, so cannot obtain or save the CacheHelper values.' );
-		}
-
-		return call_user_func_array( 'wfMemcKey', $this->cacheKey );
-	}
-
-	/**
-	 * Sets the cache key that should be used.
-	 *
-	 * @since 1.20
-	 *
-	 * @param array $cacheKey
-	 */
-	public function setCacheKey( array $cacheKey ) {
-		$this->cacheKey = $cacheKey;
-	}
-
-	/**
-	 * Rebuild the content, even if it's already cached.
-	 * This effectively has the same effect as purging the cache,
-	 * since it will be overridden with the new value on the next request.
-	 *
-	 * @since 1.20
-	 */
-	public function rebuildOnDemand() {
-		$this->hasCached = false;
-	}
-
-	/**
-	 * Sets a function that gets called when initialization of the cache is done.
-	 *
-	 * @since 1.20
-	 *
-	 * @param callable $handlerFunction
-	 */
-	public function setOnInitializedHandler( $handlerFunction ) {
-		$this->onInitHandler = $handlerFunction;
-	}
-}