memcache-8.x-2.2/src/Driver/DriverBase.php
src/Driver/DriverBase.php
<?php
namespace Drupal\memcache\Driver;
use Drupal\Component\Utility\Timer;
use Drupal\Core\Logger\LoggerChannelTrait;
use Drupal\memcache\DrupalMemcacheInterface;
use Drupal\memcache\MemcacheSettings;
/**
* Defines driver base abstract class.
*/
abstract class DriverBase implements DrupalMemcacheInterface {
use LoggerChannelTrait;
/**
* The memcache config object.
*
* @var \Drupal\memcache\MemcacheSettings
*/
protected $settings;
/**
* The memcache object.
*
* @var \Memcache|\Memcached
* E.g. \Memcache|\Memcached
*/
protected $memcache;
/**
* The hash algorithm to pass to hash(). Defaults to 'sha1'.
*
* @var string
*/
protected $hashAlgorithm;
/**
* The prefix memcache key for all keys.
*
* @var string
*/
protected $prefix;
/**
* Stats for the entire request.
*
* @var array
*/
protected static $stats = [
'all' => [],
'ops' => [],
];
/**
* Constructs a DriverBase object.
*
* @param \Drupal\memcache\MemcacheSettings $settings
* The memcache config object.
* @param \Memcached|\Memcache $memcache
* An existing memcache connection object.
* @param string $bin
* The class instance specific cache bin to use.
*/
public function __construct(MemcacheSettings $settings, $memcache, $bin = NULL) {
$this->settings = $settings;
$this->memcache = $memcache;
$this->hashAlgorithm = $this->settings->get('key_hash_algorithm', 'sha1');
$prefix = $this->settings->get('key_prefix', '');
if ($prefix) {
$this->prefix = $prefix . ':';
}
if ($bin) {
$this->prefix .= $bin . ':';
}
}
/**
* Wrapper settings method for config vs settings object.
*
* @param string $key
* The setting to be retrieved.
*
* @return array|null
* The settings for a specified parameter.
*/
protected function getMemcacheSetting($key) {
// @phpstan-ignore-next-line
$setting = \Drupal::configFactory()->getEditable('memcache.settings')->get('memcache_' . $key);
if ($setting !== NULL) {
@trigger_error('Memcache settings set via configuration is deprecated in memcache:8.x-2.6 and is removed from memcache:3.0.0. Use settings.php to set memcache variables. See https://www.drupal.org/node/3460878', E_USER_DEPRECATED);
return $setting;
}
return $this->settings->get($key);
}
/**
* {@inheritdoc}
*/
public function get($key) {
$collect_stats = $this->statsInit();
$full_key = $this->key($key);
$result = $this->memcache->get($full_key);
if ($collect_stats) {
$this->statsWrite('get', 'cache', [$full_key => (bool) $result]);
}
return $result;
}
/**
* {@inheritdoc}
*/
public function key($key) {
$full_key = urlencode($this->prefix . '-' . $key);
// Memcache only supports key lengths up to 250 bytes. If we have generated
// a longer key, we shrink it to an acceptable length with a configurable
// hashing algorithm. Sha1 was selected as the default as it performs
// quickly with minimal collisions.
if (strlen($full_key) > 250) {
$full_key = urlencode($this->prefix . '-' . hash($this->hashAlgorithm, $key));
$full_key .= '-' . substr(urlencode($key), 0, (250 - 1) - strlen($full_key) - 1);
}
return $full_key;
}
/**
* {@inheritdoc}
*/
public function delete($key) {
$collect_stats = $this->statsInit();
$full_key = $this->key($key);
$result = $this->memcache->delete($full_key, 0);
if ($collect_stats) {
$this->statsWrite('delete', 'cache', [$full_key => $result]);
}
return $result;
}
/**
* {@inheritdoc}
*/
public function flush() {
$collect_stats = $this->statsInit();
$result = $this->memcache->flush();
if ($collect_stats) {
$this->statsWrite('flush', 'cache', ['' => $result]);
}
return $result;
}
/**
* Retrieves statistics recorded during memcache operations.
*
* @param string $stats_bin
* The bin to retrieve statistics for.
* @param string $stats_type
* The type of statistics to retrieve when using the Memcache extension.
* @param bool $aggregate
* Whether to aggregate statistics.
*/
public function stats($stats_bin = 'cache', $stats_type = 'default', $aggregate = FALSE) {
// The stats_type can be over-loaded with an integer slab id, if doing a
// cachedump. We know we're doing a cachedump if $slab is non-zero.
$slab = (int) $stats_type;
$stats = [];
foreach ($this->getBins() as $bin => $target) {
if ($stats_bin == $bin) {
if (isset($this->memcache)) {
if ($this->memcache instanceof \Memcached) {
$stats[$bin] = $this->memcache->getStats();
}
// The PHP Memcache extension 3.x version throws an error if the stats
// type is NULL or not in {reset, malloc, slabs, cachedump, items,
// sizes}. If $stats_type is 'default', then no parameter should be
// passed to the Memcache memcache_get_extended_stats() function.
elseif ($this->memcache instanceof \Memcache) {
if ($stats_type == 'default' || $stats_type == '') {
$stats[$bin] = $this->memcache->getExtendedStats();
}
// If $slab isn't zero, then we are dumping the contents of a
// specific cache slab.
elseif (!empty($slab)) {
$stats[$bin] = $this->memcache->getStats('cachedump', $slab);
}
else {
$stats[$bin] = $this->memcache->getExtendedStats($stats_type);
}
}
}
}
}
// Optionally calculate a sum-total for all servers in the current bin.
if ($aggregate) {
// Some variables don't logically aggregate.
$no_aggregate = [
'pid',
'time',
'version',
'libevent',
'pointer_size',
'accepting_conns',
'listen_disabled_num',
];
foreach ($stats as $bin => $servers) {
if (is_array($servers)) {
foreach ($servers as $server) {
if (is_array($server)) {
foreach ($server as $key => $value) {
if (!in_array($key, $no_aggregate)) {
if (isset($stats[$bin]['total'][$key])) {
$stats[$bin]['total'][$key] += $value;
}
else {
$stats[$bin]['total'][$key] = $value;
}
}
}
}
}
}
}
}
return $stats;
}
/**
* Helper function to get the bins.
*/
public function getBins() {
$memcache_bins = $this->getMemcacheSetting('bins');
if (!isset($memcache_bins)) {
$memcache_bins = ['cache' => 'default'];
}
return $memcache_bins;
}
/**
* Helper function to get the servers.
*/
public function getServers() {
$memcache_servers = $this->getMemcacheSetting('servers');
$host = getenv('MEMCACHED_HOST') ?: '127.0.0.1:11211';
if (!isset($memcache_servers)) {
$memcache_servers = [$host => 'default'];
}
return $memcache_servers;
}
/**
* Helper function to get memcache.
*/
public function getMemcache() {
return $this->memcache;
}
/**
* Helper function to get request stats.
*/
public function requestStats() {
return self::$stats;
}
/**
* Returns an array of available statistics types.
*/
public function statsTypes() {
if ($this->memcache instanceof \Memcache) {
// @todo Determine which versions of the PECL memcache extension have
// these other stats types: 'malloc', 'maps', optionally detect this
// version and expose them. These stats are "subject to change without
// warning" unfortunately.
return ['default', 'slabs', 'items', 'sizes'];
}
else {
// The Memcached PECL extension only offers the default statistics.
return ['default'];
}
}
/**
* Helper function to initialize the stats for a memcache operation.
*/
protected function statsInit() {
static $drupal_static_fast;
if (!isset($drupal_static_fast)) {
// @phpcs:ignore
$drupal_static_fast = &drupal_static(__FUNCTION__, ['variable_checked' => NULL, 'user_access_checked' => NULL]);
}
$variable_checked = &$drupal_static_fast['variable_checked'];
$user_access_checked = &$drupal_static_fast['user_access_checked'];
// Confirm DRUPAL_BOOTSTRAP_VARIABLES has been reached. We don't use
// drupal_get_bootstrap_phase() as it's buggy. We can use variable_get()
// here because _drupal_bootstrap_variables() includes module.inc
// immediately after it calls variable_initialize().
// @codingStandardsIgnoreStart
// if (!isset($variable_checked) && function_exists('module_list')) {
// $variable_checked = variable_get('show_memcache_statistics', FALSE);
// }
// If statistics are enabled we need to check user access.
// if (!empty($variable_checked) && !isset($user_access_checked) && !empty($GLOBALS['user']) && function_exists('user_access')) {
// // Statistics are enabled and the $user object has been populated, so check
// // that the user has access to view them.
// $user_access_checked = user_access('access memcache statistics');
// }
// @codingStandardsIgnoreEnd
// Return whether or not statistics are enabled and the user can access
// them.
if ((!isset($variable_checked) || $variable_checked) && (!isset($user_access_checked) || $user_access_checked)) {
Timer::start('dmemcache');
return TRUE;
}
else {
return FALSE;
}
}
/**
* Memcache statistics to be displayed at end of page generation.
*
* @param string $action
* The action being performed (get, set, etc...).
* @param string $bin
* The memcache bin the action is being performed in.
* @param array $keys
* Keyed array in the form (string)$cid => (bool)$success. The keys the
* action is being performed on, and whether or not it was a success.
*/
protected function statsWrite($action, $bin, array $keys) {
// Determine how much time elapsed to execute this action.
$time = Timer::read('dmemcache');
// Build the 'all' and 'ops' arrays displayed by memcache_admin.module.
foreach ($keys as $key => $success) {
self::$stats['all'][] = [
number_format($time, 2),
$action,
$bin,
$key,
$success ? 'hit' : 'miss',
];
if (!isset(self::$stats['ops'][$action])) {
self::$stats['ops'][$action] = [$action, 0, 0, 0];
}
self::$stats['ops'][$action][1] += $time;
if ($success) {
self::$stats['ops'][$action][2]++;
}
else {
self::$stats['ops'][$action][3]++;
}
}
}
}
