memcache_storage.api.inc in Memcache Storage 7
Provide class that processes memcached operations.
File
memcache_storage.api.incView source
<?php
/**
* @file
* Provide class that processes memcached operations.
*/
/**
* Integrates with memcache API.
*/
class MemcacheStorageAPI {
// List of available memcached connections.
private static $connections;
// Unique debug key.
private static $debug_key = 0;
/**
* Connect to memcached clustes and returns memcached object on success.
*
* @param $bin
* Cache bin name. i.e. 'cache' or 'cache_bootstrap'.
*
* @return bool|object
* Memcache or memcached object is connection was successful. Otherwise FALSE.
*/
public static function openConnection($bin = '') {
// Get name of cluster for the selected cache bin storage.
$cluster_name = self::getCacheBinCluster($bin);
// Connect to the cluster and get memcached object.
if (!isset(self::$connections[$cluster_name])) {
// Store memcached object as a static object, to avoid duplicate connections to the same
// memcached cluster but for different cache bins.
self::$connections[$cluster_name] = self::connectToCluster($cluster_name);
}
return self::$connections[$cluster_name];
}
/**
* Connect to memcached cluster and return memcached object.
*
* @param $cluster_name
* Name of memcached cluster.
*
* @return object
* Connected memcached object or FALSE if no connection.
*/
protected static function connectToCluster($cluster_name) {
// Load available servers and its cluster names from settings.php.
$server_list = variable_get('memcache_servers', array(
'127.0.0.1:11211' => 'default',
));
// Search for all servers matching bin cluster.
$cluster_servers = array();
foreach ($server_list as $server => $name) {
if ($name == $cluster_name) {
$cluster_servers[] = $server;
}
}
// No servers found for this cache bin.
if (empty($cluster_servers)) {
// Log error.
self::logError('Could not find server(s) for cluster %cluster. Check your settings.php configuration.', array(
'%cluster' => $cluster_name,
));
// Return not initialized value.
return FALSE;
}
$preferred = variable_get('memcache_extension');
if (!empty($preferred) && class_exists($preferred)) {
$extension = $preferred;
}
elseif (class_exists('Memcache')) {
$extension = 'Memcache';
}
elseif (class_exists('Memcached')) {
$extension = 'Memcached';
}
// Check if Memcache extension enabled.
if (empty($extension)) {
// Log error.
self::logError('<a href="@url_memcache">Memcache</a> or <a href="@url_memcached">Memcached</a> extension is not available.', array(
'@url_memcache' => 'http://pecl.php.net/package/memcache',
'@url_memcached' => 'http://pecl.php.net/package/memcache',
));
return FALSE;
}
// Create new memcached connection.
$memcache = new $extension();
// Collect all servers thas is unable to connect.
$failed_connections = array();
// Connect to every server.
foreach ($cluster_servers as $server) {
list($host, $port) = explode(':', $server);
// Support unix sockets in the format 'unix:///path/to/socket'.
if ($host == 'unix') {
// PECL Memcache supports 'unix:///path/to/socket' path in ::addServer function,
// while PECL Memcached use only '/path/to/socket' string for the same purpose.
if ($extension == 'Memcache') {
$host = $server;
}
elseif ($extension == 'Memcached') {
$host = substr($server, 7);
}
// Port is always 0 for unix sockets.
$port = 0;
}
// Adding new server for memcached connection.
$persistent = variable_get('memcache_storage_persistent_connection', FALSE);
$connected = @$memcache
->addServer($host, $port, $persistent);
if (!$connected) {
// Mark connection to this server as 'failed'.
$failed_connections[] = $server;
// Log error if unable to connect to server.
self::logError('Could not connect to server %server (port %port).', array(
'%server' => $host,
'%port' => $port,
));
}
}
// If memcached is unable to connect to all servers it means that
// we have no connections at all, and could not start memcached connection.
if (sizeof($failed_connections) == sizeof($cluster_servers)) {
return FALSE;
}
// Provide compressThreshold support for PECL Memcached library.
if ($extension == 'Memcache') {
// For more information see http://www.php.net/manual/en/memcache.setcompressthreshold.php.
$compress_threshold = variable_get('memcache_storage_compress_threshold', array(
'threshold' => 20000,
'min_savings' => 0.2,
));
if (isset($compress_threshold['threshold']) && isset($compress_threshold['min_savings'])) {
$memcache
->setCompressThreshold($compress_threshold['threshold'], $compress_threshold['min_savings']);
}
}
elseif ($extension == 'Memcached') {
$default_options = array(
Memcached::OPT_COMPRESSION => FALSE,
Memcached::OPT_DISTRIBUTION => Memcached::DISTRIBUTION_CONSISTENT,
);
// For more info about memcached constants see http://www.php.net/manual/en/memcached.constants.php.
$memcached_options = variable_get('memcache_options', array());
$memcached_options += $default_options;
// Add SASL support.
$sasl_auth = variable_get('memcache_sasl_auth', array());
if (!empty($sasl_auth['user']) && !empty($sasl_auth['password'])) {
// SASL auth works only with binary protocol.
// Protocol has to be set before we call setSaslAuthData(), so we set
// it here specially.
$memcache
->setOption(Memcached::OPT_BINARY_PROTOCOL, TRUE);
$memcache
->setSaslAuthData($sasl_auth['user'], $sasl_auth['password']);
}
// Set memcached options.
// See http://www.php.net/manual/en/memcached.setoption.php.
foreach ($memcached_options as $key => $value) {
$memcache
->setOption($key, $value);
}
}
return $memcache;
}
/**
* Get single cache value from memcached pool.
*/
public static function get($cache_id, $cache_bin = '') {
$cache = self::getMultiple(array(
$cache_id,
), $cache_bin);
return isset($cache[$cache_id]) ? $cache[$cache_id] : FALSE;
}
/**
* Get values from memcache storage.
* Provide debug logging.
*
* @see http://www.php.net/manual/en/memcache.get.php
*/
public static function getMultiple($cache_ids, $cache_bin = '') {
// Get memcached object.
$memcache = self::openConnection($cache_bin);
// No memcached connection.
if (empty($memcache)) {
return FALSE;
}
// Process cache keys.
$cids = array();
foreach ($cache_ids as $cache_id) {
$safe_key = self::preprocessCacheKey($cache_id, $cache_bin);
$cids[$safe_key] = $cache_id;
}
// Run initial debug actions.
if (variable_get('memcache_storage_debug', FALSE)) {
self::initialDebugActions();
}
// Fetch data from memcached pool.
$cache = array();
if ($memcache instanceof Memcache) {
$cache = @$memcache
->get(array_keys($cids));
}
elseif ($memcache instanceof Memcached) {
$cache = @$memcache
->getMulti(array_keys($cids));
}
// Return cache with correct keys.
$output = array();
if (!empty($cache)) {
$cache_keys = array_keys($cache);
foreach ($cache_keys as $cache_key) {
$output[$cids[$cache_key]] = $cache[$cache_key];
}
}
// Run final debug actions.
if (variable_get('memcache_storage_debug', FALSE)) {
self::finalDebugActions('get', $cache_bin, array_values($cids), $cids, $output);
}
return $output;
}
/**
* Save data into memcached pool.
* Provide debug logging.
*
* @see http://www.php.net/manual/en/memcache.set.php
*/
public static function set($cache_id, $data, $expire, $cache_bin = '') {
// Get memcache object.
$memcache = self::openConnection($cache_bin);
// No memcache connection.
if (empty($memcache)) {
return FALSE;
}
// Build unique cache id.
$cid = self::preprocessCacheKey($cache_id, $cache_bin);
// Run initial debug actions.
if (variable_get('memcache_storage_debug', FALSE)) {
self::initialDebugActions();
}
// Set data to memcached pool.
$result = FALSE;
if ($memcache instanceof Memcache) {
// Get compression mode.
$compressed = variable_get('memcache_storage_compress_data') ? MEMCACHE_COMPRESSED : 0;
$result = @$memcache
->set($cid, $data, $compressed, $expire);
}
elseif ($memcache instanceof Memcached) {
$result = @$memcache
->set($cid, $data, $expire);
}
// Run final debug actions.
if (variable_get('memcache_storage_debug', FALSE)) {
self::finalDebugActions('set', $cache_bin, $cache_id, $cid, $result);
}
return $result;
}
/**
* Save data into memcached pool if key doesn't exist.
* Provide debug logging.
*
* @see http://www.php.net/manual/en/memcache.set.php
*/
public static function add($cache_id, $data, $expire, $cache_bin = '') {
// Get memcache object.
$memcache = self::openConnection($cache_bin);
// No memcache connection.
if (empty($memcache)) {
return FALSE;
}
// Build unique cache id.
$cid = self::preprocessCacheKey($cache_id, $cache_bin);
// Run initial debug actions.
if (variable_get('memcache_storage_debug', FALSE)) {
self::initialDebugActions();
}
// Set data to memcached pool.
$result = FALSE;
if ($memcache instanceof Memcache) {
// Get compression mode.
$compressed = variable_get('memcache_storage_compress_data') ? MEMCACHE_COMPRESSED : 0;
$result = @$memcache
->add($cid, $data, $compressed, $expire);
}
elseif ($memcache instanceof Memcached) {
@$memcache
->add($cid, $data, $expire);
$result = $memcache
->getResultCode() != Memcached::RES_SUCCESS ? FALSE : TRUE;
}
// Run final debug actions.
if (variable_get('memcache_storage_debug', FALSE)) {
self::finalDebugActions('add', $cache_bin, $cache_id, $cid, $result);
}
return $result;
}
/**
* Replace existing data in memcache pool.
* Provide debug logging.
*
* @see http://www.php.net/manual/en/memcache.replace.php
*/
public static function replace($cache_id, $data, $expire, $cache_bin = '') {
// Get memcache object.
$memcache = self::openConnection($cache_bin);
// No memcache connection.
if (empty($memcache)) {
return FALSE;
}
// Build unique cache id.
$cid = self::preprocessCacheKey($cache_id, $cache_bin);
// Run initial debug actions.
if (variable_get('memcache_storage_debug', FALSE)) {
self::initialDebugActions();
}
// Replace data if exists.
$result = FALSE;
if ($memcache instanceof Memcache) {
// Get compression mode.
$compressed = variable_get('memcache_storage_compress_data') ? MEMCACHE_COMPRESSED : 0;
$result = @$memcache
->replace($cid, $data, $compressed, $expire);
}
elseif ($memcache instanceof Memcached) {
$result = @$memcache
->replace($cid, $data, $expire);
}
// Run final debug actions.
if (variable_get('memcache_storage_debug', FALSE)) {
self::finalDebugActions('replace', $cache_bin, $cache_id, $cid, $result);
}
return $result;
}
/**
* Delete value from memcached pool.
* Provide debug logging.
*
* @see http://www.php.net/manual/en/memcache.delete.php
*/
public static function delete($cache_id, $cache_bin = '') {
// Get memcache object.
$memcache = self::openConnection($cache_bin);
// No memcache connection.
if (empty($memcache)) {
return FALSE;
}
// Build unique cache id.
$cid = self::preprocessCacheKey($cache_id, $cache_bin);
// Run initial debug actions.
if (variable_get('memcache_storage_debug', FALSE)) {
self::initialDebugActions();
}
// Delete cached data from memcached.
$result = @$memcache
->delete($cid);
// Run final debug actions.
if (variable_get('memcache_storage_debug', FALSE)) {
self::finalDebugActions('delete', $cache_bin, $cache_id, $cid, $result);
}
return $result;
}
/**
* Delete multiple cache items from memcached pool.
* Provide debug logging.
*/
public static function deleteMultiple($cache_ids, $cache_bin = '') {
// Get memcache object.
$memcache = self::openConnection($cache_bin);
// No memcache connection.
if (empty($memcache)) {
return FALSE;
}
// If current instance is Memcache which doesn't support deleteMulti
// requests, then just execute delete commands one after another.
if ($memcache instanceof Memcache) {
foreach ($cache_ids as $cache_id) {
self::delete($cache_id, $cache_bin);
}
return TRUE;
}
// Build unique cache ids.
$cids = array();
foreach ($cache_ids as $cache_id) {
$safe_key = self::preprocessCacheKey($cache_id, $cache_bin);
$cids[$safe_key] = $cache_id;
}
// Run initial debug actions.
if (variable_get('memcache_storage_debug', FALSE)) {
self::initialDebugActions();
}
$result = @$memcache
->deleteMulti(array_keys($cids));
// Return cache with correct keys.
$output = array();
if (!empty($result)) {
$cache_keys = array_keys($result);
foreach ($cache_keys as $cache_key) {
$output[$cids[$cache_key]] = $result[$cache_key];
}
}
// Run final debug actions.
if (variable_get('memcache_storage_debug', FALSE)) {
self::finalDebugActions('delete', $cache_bin, array_values($cids), $cids, $output);
}
return $output;
}
/**
* Immediately invalidates all existing items in a selected memcached cluster.
*
* @param $cluster_name
* Name of memcached cluster.
*
* @return bool
* Status of operation.
*/
public static function flushCluster($cluster_name) {
$memcache = self::connectToCluster($cluster_name);
if (!$memcache) {
return FALSE;
}
return @$memcache
->flush();
}
/**
* Immediately invalidates all existing items in all memcached clusters.
*/
public static function flushClusters() {
$servers = variable_get('memcache_servers', array(
'127.0.0.1:11211' => 'default',
));
$clusters = array();
foreach ($servers as $cluster_name) {
if (!in_array($cluster_name, $clusters)) {
$clusters[] = $cluster_name;
}
}
foreach ($clusters as $cluster_name) {
self::flushCluster($cluster_name);
}
}
/**
* Adds memcached key prefix and ensures that key is safe.
*
* @param $cache_id
* Cache ID.
*
* @param $cache_bin
* Name of cache bin.
*
* @return string
* Unique cache key.
*/
protected static function preprocessCacheKey($cache_id, $cache_bin) {
// Get key prefix from settings.php.
$key_prefix = variable_get('memcache_storage_key_prefix', '');
// Build unique cache key.
$cache_key = $key_prefix ? $key_prefix . '-' : '';
$cache_key .= $cache_bin ? $cache_bin . '-' : '';
$cache_key .= $cache_id;
// Add urlencode to avoid problems with different protocols.
// If cache bin is 'cache_page' it means that we use external page cache.
// Otherwise cache bin name is 'cache_page_[INDEX]'. We don't need to
// encode url for external page cache because external servers may not be able
// to urldecode this.
$safe_key = $cache_bin == 'cache_page' ? $cache_key : urlencode($cache_key);
// Memcache only supports key length up to 250 bytes. If we have generated
// a longer key, hash it with md5 which will shrink the key down to 32 bytes
// while still keeping it unique.
if (strlen($safe_key) > 250) {
$safe_key = md5($safe_key);
}
return $safe_key;
}
/**
* Get name of cluster where cache bin should be stored.
* Config loads from settings.php.
*
* @param $bin
* Cache bin name. i.e. 'cache' or 'cache_bootstrap'.
*
* @return string
* Cluster name.
*/
protected static function getCacheBinCluster($bin) {
// Static variable that stores cache bin
// names and mapped clusters.
static $bin_clusters = array();
// If static cache doesn't contain info about
// mapping then we should load it.
if (empty($bin_clusters[$bin])) {
// Example:
// $conf['memcache_bins'] = array(
// 'cache' => 'default',
// 'cache_bootstrap' => 'default',
// 'cache_page' => 'pages',
// );
$cluster_bins = variable_get('memcache_bins', array());
// Remove suffix from cache bin name.
$cache_bin = self::normalizeCacheBin($bin);
// Get mapped cluster.
$bin_clusters[$bin] = !empty($cluster_bins[$cache_bin]) ? $cluster_bins[$cache_bin] : 'default';
}
return $bin_clusters[$bin];
}
/**
* Trigger error if something goes wrong.
*
* @param $message
* @param array $variables
*/
protected static function logError($message, $variables = array()) {
// We can't use watchdog because this happens in a bootstrap phase
// where watchdog is non-functional. Register a shutdown handler
// instead so it gets recorded at the end of page load.
register_shutdown_function('watchdog', 'memcache_storage', $message, $variables, WATCHDOG_ERROR);
}
/**
* First step of debug logging.
* Start timer and get usage of memory before memcache action.
*/
protected static function initialDebugActions() {
$mem_usage =& drupal_static('memcache_storage_debug_mem_usage', array());
// Start count time spent on setting data to memcache.
timer_start(self::$debug_key);
// Get memory usage before set new value into cache.
$mem_usage[self::$debug_key] = memory_get_usage();
}
/**
* Last step of debug logging.
*
* @param $method
* Memcache action name. For example, 'set'.
*
* @param $cache_bin
* Cache bin name where action performs.
*
* @param $cache_id
* Unprocessed Cache ID.
*
* @param $memcache_id
* Processed Cache ID right before memcache action.
*
* @param $result
* Results of action execution.
*/
protected static function finalDebugActions($method, $cache_bin, $cache_id, $memcache_id, $result) {
// Stop count timer.
timer_stop(self::$debug_key);
// Calculate memory usage.
$mem_usage =& drupal_static('memcache_storage_debug_mem_usage', array());
$used_memory = memory_get_usage() - $mem_usage[self::$debug_key];
// Processes cache bin name (remove suffix _[INDEX] if exists).
$cache_bin_original = self::normalizeCacheBin($cache_bin);
// Get array with debug data.
$memcache_storage_debug_output =& drupal_static('memcache_storage_debug_output');
if (is_string($cache_id)) {
$cache_id = array(
$cache_id,
);
}
// Log entries about memcache action.
foreach ($cache_id as $cid) {
$unique_class = str_replace(array(
' ',
'_',
'/',
'[',
']',
':',
), '-', $cache_bin . '-' . $cid);
$clear_link = array(
'#theme' => 'link',
'#text' => 'Delete',
'#path' => 'memcache_storage/delete/nojs/' . $cache_bin . '/' . $cid,
'#options' => array(
'attributes' => array(
'class' => array(
'use-ajax',
$unique_class,
),
),
'html' => FALSE,
),
);
// Get result string (HIT or MISS).
if (is_array($result)) {
$result_status = isset($result[$cid]) && $result[$cid] !== Memcached::RES_NOTFOUND;
$result_string = !empty($result_status) ? 'HIT' : 'MISS';
}
else {
$result_string = $result ? 'HIT' : 'MISS';
}
$memcache_storage_debug_output[] = array(
'action' => count($cache_id) > 1 ? $method . 'Multiple' : $method,
'timer' => timer_read(self::$debug_key),
'memory' => $used_memory,
'result' => $result_string,
'bin' => $cache_bin_original,
'cid' => $cid,
'mem_key' => is_array($memcache_id) ? array_search($cid, $memcache_id) : $memcache_id,
'clear_link' => $cid != 'memcache_storage_bin_indexes' ? $clear_link : '',
'token' => $cache_bin . '-' . $cid,
);
}
// Increase timer to get new time results.
self::$debug_key++;
}
/**
* Removes suffix from cache bin name.
*
* @param $cache_bin
* Name of cache bin.
*
* @return string
* Return cache bin name without suffix.
*/
private static function normalizeCacheBin($cache_bin) {
$cache_bin_suffix = substr($cache_bin, strrpos($cache_bin, '_') + 1);
if (ctype_digit($cache_bin_suffix)) {
$cache_bin = substr($cache_bin, 0, strrpos($cache_bin, '_'));
}
return $cache_bin;
}
}Classes
Name |
Description |
|---|---|
| MemcacheStorageAPI | Integrates with memcache API. |