/core/model/smarty/sysplugins/smarty_cacheresource_keyvaluestore.php
PHP | 538 lines | 269 code | 24 blank | 245 comment | 42 complexity | c328ad816c98f96f7ea2c10a3e7b53fb MD5 | raw file
Possible License(s): GPL-2.0, Apache-2.0, BSD-3-Clause, LGPL-2.1
- <?php
- /**
- * Smarty Internal Plugin
- *
- * @package Smarty
- * @subpackage Cacher
- */
- /**
- * Smarty Cache Handler Base for Key/Value Storage Implementations
- * This class implements the functionality required to use simple key/value stores
- * for hierarchical cache groups. key/value stores like memcache or APC do not support
- * wildcards in keys, therefore a cache group cannot be cleared like "a|*" - which
- * is no problem to filesystem and RDBMS implementations.
- * This implementation is based on the concept of invalidation. While one specific cache
- * can be identified and cleared, any range of caches cannot be identified. For this reason
- * each level of the cache group hierarchy can have its own value in the store. These values
- * are nothing but microtimes, telling us when a particular cache group was cleared for the
- * last time. These keys are evaluated for every cache read to determine if the cache has
- * been invalidated since it was created and should hence be treated as inexistent.
- * Although deep hierarchies are possible, they are not recommended. Try to keep your
- * cache groups as shallow as possible. Anything up 3-5 parents should be ok. So
- * »a|b|c« is a good depth where »a|b|c|d|e|f|g|h|i|j|k« isn't. Try to join correlating
- * cache groups: if your cache groups look somewhat like »a|b|$page|$items|$whatever«
- * consider using »a|b|c|$page-$items-$whatever« instead.
- *
- * @package Smarty
- * @subpackage Cacher
- * @author Rodney Rehm
- */
- abstract class Smarty_CacheResource_KeyValueStore extends Smarty_CacheResource
- {
- /**
- * cache for contents
- *
- * @var array
- */
- protected $contents = array();
- /**
- * cache for timestamps
- *
- * @var array
- */
- protected $timestamps = array();
- /**
- * populate Cached Object with meta data from Resource
- *
- * @param Smarty_Template_Cached $cached cached object
- * @param Smarty_Internal_Template $_template template object
- *
- * @return void
- */
- public function populate(Smarty_Template_Cached $cached, Smarty_Internal_Template $_template)
- {
- $cached->filepath = $_template->source->uid . '#' . $this->sanitize($cached->source->resource) . '#' .
- $this->sanitize($cached->cache_id) . '#' . $this->sanitize($cached->compile_id);
- $this->populateTimestamp($cached);
- }
- /**
- * populate Cached Object with timestamp and exists from Resource
- *
- * @param Smarty_Template_Cached $cached cached object
- *
- * @return void
- */
- public function populateTimestamp(Smarty_Template_Cached $cached)
- {
- if (!$this->fetch(
- $cached->filepath,
- $cached->source->name,
- $cached->cache_id,
- $cached->compile_id,
- $content,
- $timestamp,
- $cached->source->uid
- )
- ) {
- return;
- }
- $cached->content = $content;
- $cached->timestamp = (int)$timestamp;
- $cached->exists = !!$cached->timestamp;
- }
- /**
- * Read the cached template and process the header
- *
- * @param \Smarty_Internal_Template $_smarty_tpl do not change variable name, is used by compiled template
- * @param Smarty_Template_Cached $cached cached object
- * @param boolean $update flag if called because cache update
- *
- * @return boolean true or false if the cached content does not exist
- */
- public function process(
- Smarty_Internal_Template $_smarty_tpl,
- Smarty_Template_Cached $cached = null,
- $update = false
- ) {
- if (!$cached) {
- $cached = $_smarty_tpl->cached;
- }
- $content = $cached->content ? $cached->content : null;
- $timestamp = $cached->timestamp ? $cached->timestamp : null;
- if ($content === null || !$timestamp) {
- if (!$this->fetch(
- $_smarty_tpl->cached->filepath,
- $_smarty_tpl->source->name,
- $_smarty_tpl->cache_id,
- $_smarty_tpl->compile_id,
- $content,
- $timestamp,
- $_smarty_tpl->source->uid
- )
- ) {
- return false;
- }
- }
- if (isset($content)) {
- eval('?>' . $content);
- return true;
- }
- return false;
- }
- /**
- * Write the rendered template output to cache
- *
- * @param Smarty_Internal_Template $_template template object
- * @param string $content content to cache
- *
- * @return boolean success
- */
- public function writeCachedContent(Smarty_Internal_Template $_template, $content)
- {
- $this->addMetaTimestamp($content);
- return $this->write(array($_template->cached->filepath => $content), $_template->cache_lifetime);
- }
- /**
- * Read cached template from cache
- *
- * @param Smarty_Internal_Template $_template template object
- *
- * @return string|false content
- */
- public function readCachedContent(Smarty_Internal_Template $_template)
- {
- $content = $_template->cached->content ? $_template->cached->content : null;
- $timestamp = null;
- if ($content === null) {
- if (!$this->fetch(
- $_template->cached->filepath,
- $_template->source->name,
- $_template->cache_id,
- $_template->compile_id,
- $content,
- $timestamp,
- $_template->source->uid
- )
- ) {
- return false;
- }
- }
- if (isset($content)) {
- return $content;
- }
- return false;
- }
- /**
- * Empty cache
- * {@internal the $exp_time argument is ignored altogether }}
- *
- * @param Smarty $smarty Smarty object
- * @param integer $exp_time expiration time [being ignored]
- *
- * @return integer number of cache files deleted [always -1]
- * @uses purge() to clear the whole store
- * @uses invalidate() to mark everything outdated if purge() is inapplicable
- */
- public function clearAll(Smarty $smarty, $exp_time = null)
- {
- if (!$this->purge()) {
- $this->invalidate(null);
- }
- return -1;
- }
- /**
- * Empty cache for a specific template
- * {@internal the $exp_time argument is ignored altogether}}
- *
- * @param Smarty $smarty Smarty object
- * @param string $resource_name template name
- * @param string $cache_id cache id
- * @param string $compile_id compile id
- * @param integer $exp_time expiration time [being ignored]
- *
- * @return int number of cache files deleted [always -1]
- * @throws \SmartyException
- * @uses buildCachedFilepath() to generate the CacheID
- * @uses invalidate() to mark CacheIDs parent chain as outdated
- * @uses delete() to remove CacheID from cache
- */
- public function clear(Smarty $smarty, $resource_name, $cache_id, $compile_id, $exp_time)
- {
- $uid = $this->getTemplateUid($smarty, $resource_name);
- $cid = $uid . '#' . $this->sanitize($resource_name) . '#' . $this->sanitize($cache_id) . '#' .
- $this->sanitize($compile_id);
- $this->delete(array($cid));
- $this->invalidate($cid, $resource_name, $cache_id, $compile_id, $uid);
- return -1;
- }
- /**
- * Get template's unique ID
- *
- * @param Smarty $smarty Smarty object
- * @param string $resource_name template name
- *
- * @return string filepath of cache file
- * @throws \SmartyException
- */
- protected function getTemplateUid(Smarty $smarty, $resource_name)
- {
- if (isset($resource_name)) {
- $source = Smarty_Template_Source::load(null, $smarty, $resource_name);
- if ($source->exists) {
- return $source->uid;
- }
- }
- return '';
- }
- /**
- * Sanitize CacheID components
- *
- * @param string $string CacheID component to sanitize
- *
- * @return string sanitized CacheID component
- */
- protected function sanitize($string)
- {
- $string = trim($string, '|');
- if (!$string) {
- return '';
- }
- return preg_replace('#[^\w\|]+#S', '_', $string);
- }
- /**
- * Fetch and prepare a cache object.
- *
- * @param string $cid CacheID to fetch
- * @param string $resource_name template name
- * @param string $cache_id cache id
- * @param string $compile_id compile id
- * @param string $content cached content
- * @param integer &$timestamp cached timestamp (epoch)
- * @param string $resource_uid resource's uid
- *
- * @return boolean success
- */
- protected function fetch(
- $cid,
- $resource_name = null,
- $cache_id = null,
- $compile_id = null,
- &$content = null,
- &$timestamp = null,
- $resource_uid = null
- ) {
- $t = $this->read(array($cid));
- $content = !empty($t[ $cid ]) ? $t[ $cid ] : null;
- $timestamp = null;
- if ($content && ($timestamp = $this->getMetaTimestamp($content))) {
- $invalidated =
- $this->getLatestInvalidationTimestamp($cid, $resource_name, $cache_id, $compile_id, $resource_uid);
- if ($invalidated > $timestamp) {
- $timestamp = null;
- $content = null;
- }
- }
- return !!$content;
- }
- /**
- * Add current microtime to the beginning of $cache_content
- * {@internal the header uses 8 Bytes, the first 4 Bytes are the seconds, the second 4 Bytes are the microseconds}}
- *
- * @param string &$content the content to be cached
- */
- protected function addMetaTimestamp(&$content)
- {
- $mt = explode(' ', microtime());
- $ts = pack('NN', $mt[ 1 ], (int)($mt[ 0 ] * 100000000));
- $content = $ts . $content;
- }
- /**
- * Extract the timestamp the $content was cached
- *
- * @param string &$content the cached content
- *
- * @return float the microtime the content was cached
- */
- protected function getMetaTimestamp(&$content)
- {
- extract(unpack('N1s/N1m/a*content', $content));
- /**
- * @var int $s
- * @var int $m
- */
- return $s + ($m / 100000000);
- }
- /**
- * Invalidate CacheID
- *
- * @param string $cid CacheID
- * @param string $resource_name template name
- * @param string $cache_id cache id
- * @param string $compile_id compile id
- * @param string $resource_uid source's uid
- *
- * @return void
- */
- protected function invalidate(
- $cid = null,
- $resource_name = null,
- $cache_id = null,
- $compile_id = null,
- $resource_uid = null
- ) {
- $now = microtime(true);
- $key = null;
- // invalidate everything
- if (!$resource_name && !$cache_id && !$compile_id) {
- $key = 'IVK#ALL';
- } // invalidate all caches by template
- else {
- if ($resource_name && !$cache_id && !$compile_id) {
- $key = 'IVK#TEMPLATE#' . $resource_uid . '#' . $this->sanitize($resource_name);
- } // invalidate all caches by cache group
- else {
- if (!$resource_name && $cache_id && !$compile_id) {
- $key = 'IVK#CACHE#' . $this->sanitize($cache_id);
- } // invalidate all caches by compile id
- else {
- if (!$resource_name && !$cache_id && $compile_id) {
- $key = 'IVK#COMPILE#' . $this->sanitize($compile_id);
- } // invalidate by combination
- else {
- $key = 'IVK#CID#' . $cid;
- }
- }
- }
- }
- $this->write(array($key => $now));
- }
- /**
- * Determine the latest timestamp known to the invalidation chain
- *
- * @param string $cid CacheID to determine latest invalidation timestamp of
- * @param string $resource_name template name
- * @param string $cache_id cache id
- * @param string $compile_id compile id
- * @param string $resource_uid source's filepath
- *
- * @return float the microtime the CacheID was invalidated
- */
- protected function getLatestInvalidationTimestamp(
- $cid,
- $resource_name = null,
- $cache_id = null,
- $compile_id = null,
- $resource_uid = null
- ) {
- // abort if there is no CacheID
- if (false && !$cid) {
- return 0;
- }
- // abort if there are no InvalidationKeys to check
- if (!($_cid = $this->listInvalidationKeys($cid, $resource_name, $cache_id, $compile_id, $resource_uid))) {
- return 0;
- }
- // there are no InValidationKeys
- if (!($values = $this->read($_cid))) {
- return 0;
- }
- // make sure we're dealing with floats
- $values = array_map('floatval', $values);
- return max($values);
- }
- /**
- * Translate a CacheID into the list of applicable InvalidationKeys.
- * Splits 'some|chain|into|an|array' into array( '#clearAll#', 'some', 'some|chain', 'some|chain|into', ... )
- *
- * @param string $cid CacheID to translate
- * @param string $resource_name template name
- * @param string $cache_id cache id
- * @param string $compile_id compile id
- * @param string $resource_uid source's filepath
- *
- * @return array list of InvalidationKeys
- * @uses $invalidationKeyPrefix to prepend to each InvalidationKey
- */
- protected function listInvalidationKeys(
- $cid,
- $resource_name = null,
- $cache_id = null,
- $compile_id = null,
- $resource_uid = null
- ) {
- $t = array('IVK#ALL');
- $_name = $_compile = '#';
- if ($resource_name) {
- $_name .= $resource_uid . '#' . $this->sanitize($resource_name);
- $t[] = 'IVK#TEMPLATE' . $_name;
- }
- if ($compile_id) {
- $_compile .= $this->sanitize($compile_id);
- $t[] = 'IVK#COMPILE' . $_compile;
- }
- $_name .= '#';
- $cid = trim($cache_id, '|');
- if (!$cid) {
- return $t;
- }
- $i = 0;
- while (true) {
- // determine next delimiter position
- $i = strpos($cid, '|', $i);
- // add complete CacheID if there are no more delimiters
- if ($i === false) {
- $t[] = 'IVK#CACHE#' . $cid;
- $t[] = 'IVK#CID' . $_name . $cid . $_compile;
- $t[] = 'IVK#CID' . $_name . $_compile;
- break;
- }
- $part = substr($cid, 0, $i);
- // add slice to list
- $t[] = 'IVK#CACHE#' . $part;
- $t[] = 'IVK#CID' . $_name . $part . $_compile;
- // skip past delimiter position
- $i++;
- }
- return $t;
- }
- /**
- * Check is cache is locked for this template
- *
- * @param Smarty $smarty Smarty object
- * @param Smarty_Template_Cached $cached cached object
- *
- * @return boolean true or false if cache is locked
- */
- public function hasLock(Smarty $smarty, Smarty_Template_Cached $cached)
- {
- $key = 'LOCK#' . $cached->filepath;
- $data = $this->read(array($key));
- return $data && time() - $data[ $key ] < $smarty->locking_timeout;
- }
- /**
- * Lock cache for this template
- *
- * @param Smarty $smarty Smarty object
- * @param Smarty_Template_Cached $cached cached object
- *
- * @return bool|void
- */
- public function acquireLock(Smarty $smarty, Smarty_Template_Cached $cached)
- {
- $cached->is_locked = true;
- $key = 'LOCK#' . $cached->filepath;
- $this->write(array($key => time()), $smarty->locking_timeout);
- }
- /**
- * Unlock cache for this template
- *
- * @param Smarty $smarty Smarty object
- * @param Smarty_Template_Cached $cached cached object
- *
- * @return bool|void
- */
- public function releaseLock(Smarty $smarty, Smarty_Template_Cached $cached)
- {
- $cached->is_locked = false;
- $key = 'LOCK#' . $cached->filepath;
- $this->delete(array($key));
- }
- /**
- * Read values for a set of keys from cache
- *
- * @param array $keys list of keys to fetch
- *
- * @return array list of values with the given keys used as indexes
- */
- abstract protected function read(array $keys);
- /**
- * Save values for a set of keys to cache
- *
- * @param array $keys list of values to save
- * @param int $expire expiration time
- *
- * @return boolean true on success, false on failure
- */
- abstract protected function write(array $keys, $expire = null);
- /**
- * Remove values from cache
- *
- * @param array $keys list of keys to delete
- *
- * @return boolean true on success, false on failure
- */
- abstract protected function delete(array $keys);
- /**
- * Remove *all* values from cache
- *
- * @return boolean true on success, false on failure
- */
- protected function purge()
- {
- return false;
- }
- }