vBulletin 5.6.5 API

vB_Cache

in package

• vBulletin

Uses vB_Trait_NoSerialize

Cache Handler that caches and retrieves data.

Tags

tutorial

// Application init $cache = vB_Cache::create('vB', 'Memcache');

// Read existing cache entry and lock for rebuild if it's expired $write_lock = true; if(!($data = $cache::read('hello_world', $write_lock))) { // rebuild the cache entry $data = 'Bonjour Tout Le Monde!';

if ($write_lock)
{
	// write cache, last for 50 minutes and purge on event 'widget55.update'
	$cache->write('hello_world', $data, 50, "widget{$widgetid}.update");
}

}

// Use data echo($data);

// Meanwhile... when widget 55 is updated, expire stale cache objects $cache->event("widget{$widgetid}.update");

The cache handler also provides slam prevention. Cache slams occur when a cache entry expires and multiple connections attempt to rebuild it.

see

vB_Cache::lock()

The code received a fairly significant rewrite in early 2013. Previously the cache information was stored in an object, and there was a separate observer object which tracked events and cleared cache. The cache object is now an array, and the observer methods have all been collapsed into the cache object. This got rid of a lot of code and unnecessary processing.

Table of Contents

CACHE_FAST  = 1

CACHE_LARGE  = 2

CACHE_LOG_CLEAR  = 6

CACHE_LOG_HASVALUE  = 4

CACHE_LOG_NOVALUE  = 5

CACHE_LOG_READFAIL  = 3

CACHE_LOG_READSUCCESS  = 2

CACHE_LOG_WRITE  = 1

CACHE_STD  = 0

$actions  : mixed

$cacheLogging  : mixed

$cachetype  : string

Cache type of current object.

$disableCache  : mixed

$instance  : vB_Cache

A reference to the singleton instance

$keys_used  : mixed

$meta_info  : mixed

$meta_loaded  : mixed

$metadata_life  : mixed

$metadata_update_min  : mixed

$no_values  : mixed

$noCache  : mixed

$prefix  : string

Unique prefix for item's title, required for multiple forums on the same server using the same classes that read/write to memory

$timeNow  : mixed

The current time - this is used a lot so let's make it a member variable.

$values_read  : mixed

__serialize()  : mixed

__sleep()  : mixed

__unserialize()  : mixed

__wakeup()  : mixed

allCacheEvent()  : mixed

clean()  : mixed

Cleans cache.

cleanNow()  : mixed

Tells the cache to trigger all events.

event()  : mixed

Expires cache objects based on a triggered event.

expire()  : mixed

Expires a cache object.

getContextKey()  : vB_Context

Get a context key

getDefaults()  : mixed

Get the cache defaults.

instance()  : vB_Cache

Returns an instance of the global cache.

isLoaded()  : bool

has a value been loaded for this key?

lock()  : bool

Locks a cache entry.

purge()  : mixed

Purges a cache object.

read()  : array<string|int, mixed>

Reads an array of cache objects from storage.

readSingle()  : mixed

Reads a cache object and returns the data.

resetAllCache()  : mixed

resetCache()  : mixed

restoreCacheInfo()  : mixed

If we used saveCacheInfo to save data, this will get it back.

saveCacheInfo()  : mixed

Based on the assumption that if we go back to a page we're likely to request a lot of the information we requested last time we were on that page, let's store the cached information.

shutdown()  : mixed

unlock()  : mixed

Unlocks a cache entry.

updateTime()  : mixed

This updates the time. It is useful only for testing. Otherwise it does nothing

write()  : string

Writes data as a cache object.

__construct()  : mixed

Constructor protected to enforce singleton use.

expireCache()  : bool

Sets a cache entry as expired in storage.

getSize()  : mixed

logCacheAction()  : mixed

If cache logging is enabled this stores the page cache activity to be loggged.

logCacheActivity()  : mixed

If cache logging is enabled this function writes the activity for this page to the database.

purgeCache()  : mixed

Removes a cache object from storage.

readCache()  : array<string|int, mixed>

Reads the cache object from storage.

writeCache()  : mixed

Writes the cache data to storage.

@param	integer		timestamp- optional