<?php
/**
* WP Redis
*
* This file needs to be symlinked or copied to wp-content/object-cache.php
* Users with setups where multiple installs share a common wp-config.php or $table_prefix
* can use this to guarantee uniqueness for the keys generated by this object cache.
*/
if ( ! defined( 'WP_CACHE_KEY_SALT' ) ) {
define( 'WP_CACHE_KEY_SALT', '' );
}
if ( ! defined( 'WP_REDIS_OBJECT_CACHE' ) ) {
define( 'WP_REDIS_OBJECT_CACHE', true );
}
if ( ! defined( 'WP_REDIS_USE_CACHE_GROUPS' ) ) {
define( 'WP_REDIS_USE_CACHE_GROUPS', false );
}
if ( ! defined( 'WP_REDIS_DEFAULT_EXPIRE_SECONDS' ) ) {
define( 'WP_REDIS_DEFAULT_EXPIRE_SECONDS', 0 );
}
if ( ! defined( 'WP_REDIS_IGNORE_GLOBAL_GROUPS' ) ) {
define( 'WP_REDIS_IGNORE_GLOBAL_GROUPS', false );
}
/**
* Adds data to the cache, if the cache key doesn't already exist.
*
* @uses $wp_object_cache Object Cache Class
* @see WP_Object_Cache::add()
*
* @param int|string $key The cache key to use for retrieval later
* @param mixed $data The data to add to the cache store
* @param string $group The group to add the cache to
* @param int $expire When the cache data should be expired
* @return bool False if cache key and group already exist, true on success
*/
function wp_cache_add( $key, $data, $group = '', $expire = WP_REDIS_DEFAULT_EXPIRE_SECONDS ) {
global $wp_object_cache;
return $wp_object_cache->add( $key, $data, $group, (int) $expire );
}
/**
* Closes the cache.
*
* This function has ceased to do anything since WordPress 2.5. The
* functionality was removed along with the rest of the persistent cache. This
* does not mean that plugins can't implement this function when they need to
* make sure that the cache is cleaned up after WordPress no longer needs it.
*
* @return bool Always returns True
*/
function wp_cache_close() {
return true;
}
/**
* Decrement numeric cache item's value
*
* @uses $wp_object_cache Object Cache Class
* @see WP_Object_Cache::decr()
*
* @param int|string $key The cache key to increment
* @param int $offset The amount by which to decrement the item's value. Default is 1.
* @param string $group The group the key is in.
* @return false|int False on failure, the item's new value on success.
*/
function wp_cache_decr( $key, $offset = 1, $group = '' ) {
global $wp_object_cache;
return $wp_object_cache->decr( $key, $offset, $group );
}
/**
* Removes the cache contents matching key and group.
*
* @uses $wp_object_cache Object Cache Class
* @see WP_Object_Cache::delete()
*
* @param int|string $key What the contents in the cache are called
* @param string $group Where the cache contents are grouped
* @return bool True on successful removal, false on failure
*/
function wp_cache_delete( $key, $group = '' ) {
global $wp_object_cache;
return $wp_object_cache->delete( $key, $group );
}
/**
* Removes cache contents for a given group.
*
* @uses $wp_object_cache Object Cache Class
* @see WP_Object_Cache::delete_group()
*
* @param string $group Where the cache contents are grouped
* @return bool True on successful removal, false on failure
*/
function wp_cache_delete_group( $group ) {
global $wp_object_cache;
return $wp_object_cache->delete_group( $group );
}
/**
* Removes all cache items.
*
* @uses $wp_object_cache Object Cache Class
* @see WP_Object_Cache::flush()
*
* @return bool False on failure, true on success
*/
function wp_cache_flush() {
global $wp_object_cache;
return $wp_object_cache->flush();
}
/**
* Retrieves the cache contents from the cache by key and group.
*
* @uses $wp_object_cache Object Cache Class
* @see WP_Object_Cache::get()
*
* @param int|string $key What the contents in the cache are called
* @param string $group Where the cache contents are grouped
* @param bool $force Whether to force an update of the local cache from the persistent cache (default is false)
* @param &bool $found Whether key was found in the cache. Disambiguates a return of false, a storable value.
* @return bool|mixed False on failure to retrieve contents or the cache contents on success
*/
function wp_cache_get( $key, $group = '', $force = false, &$found = null ) {
global $wp_object_cache;
return $wp_object_cache->get( $key, $group, $force, $found );
}
/**
* Retrieves multiple values from the cache in one call.
*
* @see WP_Object_Cache::get_multiple()
* @global WP_Object_Cache $wp_object_cache Object cache global instance.
*
* @param array $keys Array of keys under which the cache contents are stored.
* @param string $group Optional. Where the cache contents are grouped. Default empty.
* @param bool $force Optional. Whether to force an update of the local cache
* from the persistent cache. Default false.
* @return array Array of values organized into groups.
*/
function wp_cache_get_multiple( $keys, $group = '', $force = false ) {
global $wp_object_cache;
return $wp_object_cache->get_multiple( $keys, $group, $force );
}
/**
* Removes all cache items from the in-memory runtime cache.
*
* @see WP_Object_Cache::flush()
*
* @return bool True on success, false on failure.
*/
function wp_cache_flush_runtime() {
global $wp_object_cache;
return $wp_object_cache->flush( false );
}
/**
* Removes all cache items in a group, if the object cache implementation supports it.
*
* Before calling this function, always check for group flushing support using the
* `wp_cache_supports( 'flush_group' )` function.
*
* @see WP_Object_Cache::flush_group()
* @global WP_Object_Cache $wp_object_cache Object cache global instance.
*
* @param string $group Name of group to remove from cache.
* @return bool True if group was flushed, false otherwise.
*/
function wp_cache_flush_group( $group ) {
global $wp_object_cache;
return $wp_object_cache->flush_group( $group );
}
/**
* Increment numeric cache item's value
*
* @uses $wp_object_cache Object Cache Class
* @see WP_Object_Cache::incr()
*
* @param int|string $key The cache key to increment
* @param int $offset The amount by which to increment the item's value. Default is 1.
* @param string $group The group the key is in.
* @return false|int False on failure, the item's new value on success.
*/
function wp_cache_incr( $key, $offset = 1, $group = '' ) {
global $wp_object_cache;
return $wp_object_cache->incr( $key, $offset, $group );
}
/**
* Sets up Object Cache Global and assigns it.
*
* @global WP_Object_Cache $wp_object_cache WordPress Object Cache
*/
function wp_cache_init() {
global $wp_object_cache;
if ( ! ( $wp_object_cache instanceof WP_Object_Cache ) ) {
$wp_object_cache = new WP_Object_Cache();
}
}
/**
* Replaces the contents of the cache with new data.
*
* @uses $wp_object_cache Object Cache Class
* @see WP_Object_Cache::replace()
*
* @param int|string $key What to call the contents in the cache
* @param mixed $data The contents to store in the cache
* @param string $group Where to group the cache contents
* @param int $expire When to expire the cache contents
* @return bool False if not exists, true if contents were replaced
*/
function wp_cache_replace( $key, $data, $group = '', $expire = WP_REDIS_DEFAULT_EXPIRE_SECONDS ) {
global $wp_object_cache;
return $wp_object_cache->replace( $key, $data, $group, (int) $expire );
}
/**
* Saves the data to the cache.
*
* @uses $wp_object_cache Object Cache Class
* @see WP_Object_Cache::set()
*
* @param int|string $key What to call the contents in the cache
* @param mixed $data The contents to store in the cache
* @param string $group Where to group the cache contents
* @param int $expire When to expire the cache contents
* @return bool False on failure, true on success
*/
function wp_cache_set( $key, $data, $group = '', $expire = WP_REDIS_DEFAULT_EXPIRE_SECONDS ) {
global $wp_object_cache;
return $wp_object_cache->set( $key, $data, $group, (int) $expire );
}
/**
* Switch the interal blog id.
*
* This changes the blog id used to create keys in blog specific groups.
*
* @param int $blog_id Blog ID
*/
function wp_cache_switch_to_blog( $blog_id ) {
global $wp_object_cache;
return $wp_object_cache->switch_to_blog( $blog_id );
}
/**
* Adds a group or set of groups to the list of global groups.
*
* @param string|array $groups A group or an array of groups to add
*/
function wp_cache_add_global_groups( $groups ) {
global $wp_object_cache;
return $wp_object_cache->add_global_groups( $groups );
}
/**
* Adds a group or set of groups to the list of non-persistent groups.
*
* @param string|array $groups A group or an array of groups to add
*/
function wp_cache_add_non_persistent_groups( $groups ) {
global $wp_object_cache;
$wp_object_cache->add_non_persistent_groups( $groups );
}
/**
* Adds a group or set of groups to the list of groups that use Redis hashes.
*
* @param string|array $groups A group or an array of groups to add.
*/
function wp_cache_add_redis_hash_groups( $groups ) {
global $wp_object_cache;
$wp_object_cache->add_redis_hash_groups( $groups );
}
/**
* Reset internal cache keys and structures. If the cache backend uses global
* blog or site IDs as part of its cache keys, this function instructs the
* backend to reset those keys and perform any cleanup since blog or site IDs
* have changed since cache init.
*
* This function is deprecated. Use wp_cache_switch_to_blog() instead of this
* function when preparing the cache for a blog switch. For clearing the cache
* during unit tests, consider using wp_cache_init(). wp_cache_init() is not
* recommended outside of unit tests as the performance penality for using it is
* high.
*
* @deprecated 3.5.0
*/
function wp_cache_reset() {
_deprecated_function( __FUNCTION__, '3.5' );
global $wp_object_cache;
return $wp_object_cache->reset();
}
/**
* Determines whether the object cache implementation supports a particular feature.
*
* @since 6.1.0
*
* @param string $feature Name of the feature to check for. Possible values include:
* 'add_multiple', 'set_multiple', 'get_multiple', 'delete_multiple',
* 'flush_runtime', 'flush_group'.
* @return bool True if the feature is supported, false otherwise.
*/
function wp_cache_supports( $feature ) {
switch ( $feature ) {
case 'get_multiple':
case 'flush_runtime':
case 'flush_group':
return true;
case 'add_multiple':
case 'set_multiple':
case 'delete_multiple':
default:
return false;
}
}
/**
* WordPress Object Cache
*
* The WordPress Object Cache is used to save on trips to the database. The
* Object Cache stores all of the cache data to memory and makes the cache
* contents available by using a key, which is used to name and later retrieve
* the cache contents.
*
* The Object Cache can be replaced by other caching mechanisms by placing files
* in the wp-content folder which is looked at in wp-settings. If that file
* exists, then this file will not be included.
*/
#[AllowDynamicProperties]
class WP_Object_Cache {
/**
* Holds the cached objects
*
* @var array
*/
public $cache = [];
/**
* The amount of times the cache data was already stored in the cache.
*
* @var int
*/
public $cache_hits = 0;
/**
* Amount of times the cache did not have the request in cache
*
* @var int
*/
public $cache_misses = 0;
/**
* The amount of times a request was made to Redis
*
* @var int
*/
public $redis_calls = [];
/**
* List of global groups
*
* @var array
*/
public $global_groups = [];
/**
* List of non-persistent groups
*
* @var array
*/
public $non_persistent_groups = [];
/**
* List of groups which use Redis hashes.
*
* @var array
*/
public $redis_hash_groups = [];
/**
* The blog prefix to prepend to keys in non-global groups.
*
* @var int
*/
public $blog_prefix;
/**
* Whether or not Redis is connected
*
* @var bool
*/
public $is_redis_connected = false;
/**
* Whether or not the object cache thinks Redis needs a flush
*
* @var bool
*/
public $do_redis_failback_flush = false;
/**
* The last triggered error
*
* @var string
*/
public $last_triggered_error = '';
/**
* Whether or not to use true cache groups, instead of flattening.
*
* @var bool
*/
const USE_GROUPS = WP_REDIS_USE_CACHE_GROUPS;
/**
* Adds data to the cache if it doesn't already exist.
*
* @uses WP_Object_Cache::_exists Checks to see if the cache already has data.
* @uses WP_Object_Cache::set Sets the data after the checking the cache
* contents existence.
*
* @param int|string $key What to call the contents in the cache
* @param mixed $data The contents to store in the cache
* @param string $group Where to group the cache contents
* @param int $expire When to expire the cache contents
* @return bool False if cache key and group already exist, true on success
*/
public function add( $key, $data, $group = 'default', $expire = WP_REDIS_DEFAULT_EXPIRE_SECONDS ) {
if ( empty( $group ) ) {
$group = 'default';
}
if ( function_exists( 'wp_suspend_cache_addition' ) && wp_suspend_cache_addition() ) {
return false;
}
if ( $this->_exists( $key, $group ) ) {
return false;
}
return $this->set( $key, $data, $group, (int) $expire );
}
/**
* Sets the list of global groups.
*
* @param array $groups List of groups that are global.
*/
public function add_global_groups( $groups ) {
$groups = (array) $groups;
// Allow force ignoring of global groups.
if ( is_array( WP_REDIS_IGNORE_GLOBAL_GROUPS ) ) {
$groups = array_diff( $groups, WP_REDIS_IGNORE_GLOBAL_GROUPS );
}
$groups = array_fill_keys( $groups, true );
$this->global_groups = array_merge( $this->global_groups, $groups );
}
/**
* Sets the list of non-persistent groups.
*
* @param array $groups List of groups that are non-persistent.
*/
public function add_non_persistent_groups( $groups ) {
$groups = (array) $groups;
$groups = array_fill_keys( $groups, true );
$this->non_persistent_groups = array_merge( $this->non_persistent_groups, $groups );
}
/**
* Sets the list of groups that use Redis hashes.
*
* @param array $groups List of groups that use Redis hashes.
*/
public function add_redis_hash_groups( $groups ) {
$groups = (array) $groups;
$groups = array_fill_keys( $groups, true );
$this->redis_hash_groups = array_merge( $this->redis_hash_groups, $groups );
}
/**
* Decrement numeric cache item's value
*
* @param int|string $key The cache key to increment
* @param int $offset The amount by which to decrement the item's value. Default is 1.
* @param string $group The group the key is in.
* @return false|int False on failure, the item's new value on success.
*/
public function decr( $key, $offset = 1, $group = 'default' ) {
if ( empty( $group ) ) {
$group = 'default';
}
// The key needs to exist in order to be decremented.
if ( ! $this->_exists( $key, $group ) ) {
return false;
}
$offset = (int) $offset;
// If this isn't a persistant group, we have to sort this out ourselves, grumble grumble.
if ( ! $this->_should_persist( $group ) ) {
$existing = $this->_get_internal( $key, $group );
if ( empty( $existing ) || ! is_numeric( $existing ) ) {
$existing = 0;
} else {
$existing -= $offset;
}
if ( $existing < 0 ) {
$existing = 0;
}
$this->_set_internal( $key, $group, $existing );
return $existing;
}
if ( $this->_should_use_redis_hashes( $group ) ) {
$redis_safe_group = $this->_key( '', $group );
$result = $this->_call_redis( 'hIncrBy', $redis_safe_group, $key, -$offset, $group );
if ( $result < 0 ) {
$result = 0;
$this->_call_redis( 'hSet', $redis_safe_group, $key, $result );
}
} else {
$id = $this->_key( $key, $group );
$result = $this->_call_redis( 'decrBy', $id, $offset );
if ( $result < 0 ) {
$result = 0;
$this->_call_redis( 'set', $id, $result );
}
}
if ( is_int( $result ) ) {
$this->_set_internal( $key, $group, $result );
}
return $result;
}
/**
* Remove the contents of the cache key in the group
*
* If the cache key does not exist in the group and $force parameter is set
* to false, then nothing will happen. The $force parameter is set to false
* by default.
*
* @param int|string $key What the contents in the cache are called
* @param string $group Where the cache contents are grouped
* @param bool $force Optional. Whether to force the unsetting of the cache
* key in the group
* @return bool False if the contents weren't deleted and true on success
*/
public function delete( $key, $group = 'default', $force = false ) {
if ( empty( $group ) ) {
$group = 'default';
}
if ( ! $force && ! $this->_exists( $key, $group ) ) {
return false;
}
if ( $this->_should_persist( $group ) ) {
if ( $this->_should_use_redis_hashes( $group ) ) {
$redis_safe_group = $this->_key( '', $group );
$result = $this->_call_redis( 'hDel', $redis_safe_group, $key );
} else {
$id = $this->_key( $key, $group );
$result = $this->_call_redis( 'del', $id );
}
if ( 1 !== $result ) {
return false;
}
}
$this->_unset_internal( $key, $group );
return true;
}
/**
* Remove the contents of all cache keys in the group.
*
* @param string $group Where the cache contents are grouped.
* @return boolean True on success, false on failure.
*/
public function delete_group( $group ) {
if ( ! $this->_should_use_redis_hashes( $group ) ) {
return false;
}
$multisite_safe_group = $this->multisite && ! isset( $this->global_groups[ $group ] ) ? $this->blog_prefix . $group : $group;
$redis_safe_group = $this->_key( '', $group );
if ( $this->_should_persist( $group ) ) {
$result = $this->_call_redis( 'del', $redis_safe_group );
if ( 1 !== $result ) {
return false;
}
} elseif ( ! $this->_should_persist( $group ) && ! isset( $this->cache[ $multisite_safe_group ] ) ) {
return false;
}
unset( $this->cache[ $multisite_safe_group ] );
return true;
}
/**
* Clears the object cache of all data.
*
* By default, this will flush the session cache as well as Redis, but we
* can leave the redis cache intact if we want. This is helpful when, for
* instance, you're running a batch process and want to clear the session
* store to reduce the memory footprint, but you don't want to have to
* re-fetch all the values from the database.
*
* @param bool $redis Should we flush redis as well as the session cache?
* @return bool Always returns true
*/
public function flush( $redis = true ) {
$this->cache = [];
if ( $redis ) {
$this->_call_redis( 'flushdb' );
}
return true;
}
/**
* Removes all cache items in a group.
*
* @param string $group Name of group to remove from cache.
* @return true Always returns true.
*/
public function flush_group( $group ) {
if ( ! $this->_should_use_redis_hashes( $group ) ) {
return false;
}
$multisite_safe_group = $this->multisite && ! isset( $this->global_groups[ $group ] ) ? $this->blog_prefix . $group : $group;
$redis_safe_group = $this->_key( '', $group );
if ( $this->_should_persist( $group ) ) {
$result = $this->_call_redis( 'del', $redis_safe_group );
if ( 1 !== $result ) {
return false;
}
} elseif ( ! $this->_should_persist( $group ) && ! isset( $this->cache[ $multisite_safe_group ] ) ) {
return false;
}
unset( $this->cache[ $multisite_safe_group ] );
return true;
}
/**
* Retrieves the cache contents, if it exists
*
* The contents will be first attempted to be retrieved by searching by the
* key in the cache group. If the cache is hit (success) then the contents
* are returned.
*
* On failure, the number of cache misses will be incremented.
*
* @param int|string $key What the contents in the cache are called
* @param string $group Where the cache contents are grouped
* @param string $force Whether to force a refetch rather than relying on the local cache (default is false)
* @param bool $found Optional. Whether the key was found in the cache. Disambiguates a return of false, a storable value. Passed by reference. Default null.
* @return bool|mixed False on failure to retrieve contents or the cache contents on success
*/
public function get( $key, $group = 'default', $force = false, &$found = null ) {
if ( empty( $group ) ) {
$group = 'default';
}
// Key is set internally, so we can use this value.
if ( $this->_isset_internal( $key, $group ) && ! $force ) {
$this->cache_hits += 1;
$found = true;
return $this->_get_internal( $key, $group );
}
// Not a persistent group, so don't try Redis if the value doesn't exist internally.
if ( ! $this->_should_persist( $group ) ) {
$this->cache_misses += 1;
$found = false;
return false;
}
if ( $this->_should_use_redis_hashes( $group ) ) {
$redis_safe_group = $this->_key( '', $group );
$value = $this->_call_redis( 'hGet', $redis_safe_group, $key );
} else {
$id = $this->_key( $key, $group );
$value = $this->_call_redis( 'get', $id );
}
// PhpRedis returns `false` when the key doesn't exist.
if ( false === $value ) {
$this->cache_misses += 1;
$found = false;
return false;
}
// All non-numeric values are serialized.
$value = is_numeric( $value ) ? intval( $value ) : unserialize( $value );
$this->_set_internal( $key, $group, $value );
$this->cache_hits += 1;
$found = true;
return $value;
}
/**
* Retrieves multiple values from the cache in one call.
*
* @param array $keys Array of keys under which the cache contents are stored.
* @param string $group Optional. Where the cache contents are grouped. Default empty.
* @param bool $force Optional. Whether to force an update of the local cache
* from the persistent cache. Default false.
* @return array Array of values organized into groups.
*/
public function get_multiple( $keys, $group = 'default', $force = false ) {
if ( empty( $group ) ) {
$group = 'default';
}
$cache = [];
if ( ! $this->_should_persist( $group ) ) {
foreach ( $keys as $key ) {
$cache[ $key ] = $this->_isset_internal( $key, $group ) ? $this->_get_internal( $key, $group ) : false;
false !== $cache[ $key ] ? $this->cache_hits++ : $this->cache_misses++;
}
return $cache;
}
// Attempt to fetch values from the internal cache.
if ( ! $force ) {
foreach ( $keys as $key ) {
if ( $this->_isset_internal( $key, $group ) ) {
$cache[ $key ] = $this->_get_internal( $key, $group );
$this->cache_hits++;
}
}
}
$remaining_keys = array_values( array_diff( $keys, array_keys( $cache ) ) );
// If all keys were satisfied by the internal cache, we're sorted.
if ( empty( $remaining_keys ) ) {
return $cache;
}
if ( $this->_should_use_redis_hashes( $group ) ) {
$redis_safe_group = $this->_key( '', $group );
$results = $this->_call_redis( 'hmGet', $redis_safe_group, $remaining_keys );
$results = is_array( $results ) ? array_values( $results ) : $results;
} else {
$ids = [];
foreach ( $remaining_keys as $key ) {
$ids[] = $this->_key( $key, $group );
}
$results = $this->_call_redis( 'mget', $ids );
}
// Process the results from the Redis call.
foreach ( $remaining_keys as $i => $key ) {
$value = isset( $results[ $i ] ) ? $results[ $i ] : false;
if ( false !== $value ) {
// All non-numeric values are serialized.
$value = is_numeric( $value ) ? intval( $value ) : unserialize( $value );
$this->_set_internal( $key, $group, $value );
$this->cache_hits++;
} else {
$this->cache_misses++;
}
$cache[ $key ] = $value;
}
// Make sure return values are returned in the order of the passed keys.
$return_cache = [];
foreach ( $keys as $key ) {
$return_cache[ $key ] = isset( $cache[ $key ] ) ? $cache[ $key ] : false;
}
return $return_cache;
}
/**
* Increment numeric cache item's value
*
* @param int|string $key The cache key to increment
* @param int $offset The amount by which to increment the item's value. Default is 1.
* @param string $group The group the key is in.
* @return false|int False on failure, the item's new value on success.
*/
public function incr( $key, $offset = 1, $group = 'default' ) {
if ( empty( $group ) ) {
$group = 'default';
}
// The key needs to exist in order to be incremented.
if ( ! $this->_exists( $key, $group ) ) {
return false;
}
$offset = (int) $offset;
// If this isn't a persistant group, we have to sort this out ourselves, grumble grumble.
if ( ! $this->_should_persist( $group ) ) {
$existing = $this->_get_internal( $key, $group );
if ( empty( $existing ) || ! is_numeric( $existing ) ) {
$existing = 1;
} else {
$existing += $offset;
}
if ( $existing < 0 ) {
$existing = 0;
}
$this->_set_internal( $key, $group, $existing );
return $existing;
}
if ( $this->_should_use_redis_hashes( $group ) ) {
$redis_safe_group = $this->_key( '', $group );
$result = $this->_call_redis( 'hIncrBy', $redis_safe_group, $key, $offset, $group );
if ( $result < 0 ) {
$result = 0;
$this->_call_redis( 'hSet', $redis_safe_group, $key, $result );
}
} else {
$id = $this->_key( $key, $group );
$result = $this->_call_redis( 'incrBy', $id, $offset );
if ( $result < 0 ) {
$result = 0;
$this->_call_redis( 'set', $id, $result );
}
}
if ( is_int( $result ) ) {
$this->_set_internal( $key, $group, $result );
}
return $result;
}
/**
* Replace the contents in the cache, if contents already exist
*
* @see WP_Object_Cache::set()
*
* @param int|string $key What to call the contents in the cache
* @param mixed $data The contents to store in the cache
* @param string $group Where to group the cache contents
* @param int $expire When to expire the cache contents
* @return bool False if not exists, true if contents were replaced
*/
public function replace( $key, $data, $group = 'default', $expire = WP_REDIS_DEFAULT_EXPIRE_SECONDS ) {
if ( empty( $group ) ) {
$group = 'default';
}
if ( ! $this->_exists( $key, $group ) ) {
return false;
}
return $this->set( $key, $data, $group, (int) $expire );
}
/**
* Reset keys
*
* @deprecated 3.5.0
*/
public function reset() {
_deprecated_function( __FUNCTION__, '3.5', 'switch_to_blog()' );
}
/**
* Sets the data contents into the cache
*
* The cache contents is grouped by the $group parameter followed by the
* $key. This allows for duplicate ids in unique groups. Therefore, naming of
* the group should be used with care and should follow normal function
* naming guidelines outside of core WordPress usage.
*
* The $expire parameter is not used, because the cache will automatically
* expire for each time a page is accessed and PHP finishes. The method is
* more for cache plugins which use files.
*
* @param int|string $key What to call the contents in the cache
* @param mixed $data The contents to store in the cache
* @param string $group Where to group the cache contents
* @param int $expire TTL for the data, in seconds
* @return bool Always returns true
*/
public function set( $key, $data, $group = 'default', $expire = WP_REDIS_DEFAULT_EXPIRE_SECONDS ) {
if ( empty( $group ) ) {
$group = 'default';
}
if ( is_object( $data ) ) {
$data = clone $data;
}
$this->_set_internal( $key, $group, $data );
if ( ! $this->_should_persist( $group ) ) {
return true;
}
// If this is an integer, store it as such. Otherwise, serialize it.
if ( ! is_numeric( $data ) || intval( $data ) !== $data ) {
$data = serialize( $data );
}
// Redis doesn't support expire on hash group keys.
if ( $this->_should_use_redis_hashes( $group ) ) {
$redis_safe_group = $this->_key( '', $group );
$this->_call_redis( 'hSet', $redis_safe_group, $key, $data );
return true;
}
$id = $this->_key( $key, $group );
if ( empty( $expire ) ) {
$this->_call_redis( 'set', $id, $data );
} else {
$this->_call_redis( 'setex', $id, $expire, $data );
}
return true;
}
/**
* Echoes the stats of the caching.
*
* Gives the cache hits, and cache misses. Also prints every cached group,
* key and the data.
*/
public function stats() {
$total_redis_calls = 0;
foreach ( $this->redis_calls as $method => $calls ) {
$total_redis_calls += $calls;
}
$out = [];
$out[] = '<p>';
$out[] = '<strong>Cache Hits:</strong>' . (int) $this->cache_hits . '<br />';
$out[] = '<strong>Cache Misses:</strong>' . (int) $this->cache_misses . '<br />';
$out[] = '<strong>Redis Client:</strong>' . get_class( $this->redis ) . '<br />';
$out[] = '<strong>Redis Calls:</strong>' . (int) $total_redis_calls . ':<br />';
foreach ( $this->redis_calls as $method => $calls ) {
$out[] = ' - ' . esc_html( $method ) . ': ' . (int) $calls . '<br />';
}
$out[] = '</p>';
$out[] = '<ul>';
foreach ( $this->cache as $group => $cache ) {
$out[] = '<li><strong>Group:</strong> ' . esc_html( $group ) . ' - ( ' . number_format( strlen( serialize( $cache ) ) / 1024, 2 ) . 'k )</li>';
}
$out[] = '</ul>';
echo implode( PHP_EOL, $out ); // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
}
/**
* Switch the interal blog id.
*
* This changes the blog id used to create keys in blog specific groups.
*
* @param int $blog_id Blog ID
*/
public function switch_to_blog( $blog_id ) {
$blog_id = (int) $blog_id;
$this->blog_prefix = $this->multisite ? $blog_id . ':' : '';
}
/**
* Utility function to determine whether a key exists in the cache.
*
* @param string $key The key to check for existence.
* @param string $group The group to which the key belongs.
*
* @access protected
*/
protected function _exists( $key, $group ) {
if ( $this->_isset_internal( $key, $group ) ) {
return true;
}
if ( ! $this->_should_persist( $group ) ) {
return false;
}
if ( $this->_should_use_redis_hashes( $group ) ) {
$redis_safe_group = $this->_key( '', $group );
return $this->_call_redis( 'hExists', $redis_safe_group, $key );
}
$id = $this->_key( $key, $group );
return $this->_call_redis( 'exists', $id );
}
/**
* Check whether there's a value in the internal object cache.
*
* @param string $key The key to check for existence.
* @param string $group The group to which the key belongs.
* @return boolean
*/
protected function _isset_internal( $key, $group ) {
if ( $this->_should_use_redis_hashes( $group ) ) {
$multisite_safe_group = $this->multisite && ! isset( $this->global_groups[ $group ] ) ? $this->blog_prefix . $group : $group;
return isset( $this->cache[ $multisite_safe_group ] ) && array_key_exists( $key, $this->cache[ $multisite_safe_group ] );
} else {
$key = $this->_key( $key, $group );
return array_key_exists( $key, $this->cache );
}
}
/**
* Get a value from the internal object cache
*
* @param string $key The key to the value to get.
* @param string $group The group to which the key belongs.
* @return mixed
*/
protected function _get_internal( $key, $group ) {
$value = null;
if ( $this->_should_use_redis_hashes( $group ) ) {
$multisite_safe_group = $this->multisite && ! isset( $this->global_groups[ $group ] ) ? $this->blog_prefix . $group : $group;
if ( isset( $this->cache[ $multisite_safe_group ] ) && array_key_exists( $key, $this->cache[ $multisite_safe_group ] ) ) {
$value = $this->cache[ $multisite_safe_group ][ $key ];
}
} else {
$key = $this->_key( $key, $group );
if ( array_key_exists( $key, $this->cache ) ) {
$value = $this->cache[ $key ];
}
}
if ( is_object( $value ) ) {
return clone $value;
}
return $value;
}
/**
* Set a value to the internal object cache
*
* @param string $key The key to the value to set.
* @param string $group The group to which the key belongs.
* @param mixed $value The value to set.
*/
protected function _set_internal( $key, $group, $value ) {
if ( $this->_should_use_redis_hashes( $group ) ) {
$multisite_safe_group = $this->multisite && ! isset( $this->global_groups[ $group ] ) ? $this->blog_prefix . $group : $group;
if ( ! isset( $this->cache[ $multisite_safe_group ] ) ) {
$this->cache[ $multisite_safe_group ] = [];
}
$this->cache[ $multisite_safe_group ][ $key ] = $value;
} else {
$key = $this->_key( $key, $group );
$this->cache[ $key ] = $value;
}
}
/**
* Unset a value from the internal object cache
*
* @param string $key The key to the value to unset.
* @param string $group The group to which the key belongs.
*/
protected function _unset_internal( $key, $group ) {
if ( $this->_should_use_redis_hashes( $group ) ) {
$multisite_safe_group = $this->multisite && ! isset( $this->global_groups[ $group ] ) ? $this->blog_prefix . $group : $group;
if ( isset( $this->cache[ $multisite_safe_group ] ) && array_key_exists( $key, $this->cache[ $multisite_safe_group ] ) ) {
unset( $this->cache[ $multisite_safe_group ][ $key ] );
}
} else {
$key = $this->_key( $key, $group );
if ( array_key_exists( $key, $this->cache ) ) {
unset( $this->cache[ $key ] );
}
}
}
/**
* Utility function to generate the redis key for a given key and group.
*
* @param string $key The cache key.
* @param string $group The cache group.
* @return string A properly prefixed redis cache key.
*/
protected function _key( $key = '', $group = 'default' ) {
if ( empty( $group ) ) {
$group = 'default';
}
if ( ! empty( $this->global_groups[ $group ] ) ) {
$prefix = $this->global_prefix;
} else {
$prefix = $this->blog_prefix;
}
return preg_replace( '/\s+/', '', WP_CACHE_KEY_SALT . "$prefix$group:$key" );
}
/**
* Does this group use persistent storage?
*
* @param string $group Cache group.
* @return bool true if the group is persistent, false if not.
*/
protected function _should_persist( $group ) {
return empty( $this->non_persistent_groups[ $group ] );
}
/**
* Should this group use Redis hashes?
*
* @param string $group Cache group.
* @return bool True if the group should use Redis hashes, false if not.
*/
protected function _should_use_redis_hashes( $group ) {
if ( self::USE_GROUPS || ! empty( $this->redis_hash_groups[ $group ] ) ) {
return true;
}
return false;
}
/**
* Wrapper method for connecting to Redis, which lets us retry the connection
*/
protected function _connect_redis() {
global $redis_server;
$check_dependencies = [ $this, 'check_client_dependencies' ];
/**
* Permits alternate dependency check mechanism to be used.
*
* @param callable $check_dependencies Callback to execute.
*/
$check_dependencies = apply_filters( 'wp_redis_check_client_dependencies_callback', $check_dependencies );
$dependencies_ok = call_user_func( $check_dependencies );
if ( true !== $dependencies_ok ) {
$this->is_redis_connected = false;
$this->missing_redis_message = $dependencies_ok;
return $this->is_redis_connected;
}
$client_parameters = $this->build_client_parameters( $redis_server );
try {
$client_connection = [ $this, 'prepare_client_connection' ];
/**
* Permits alternate initial client connection mechanism to be used.
*
* @param callable $client_connection Callback to execute.
*/
$client_connection = apply_filters( 'wp_redis_prepare_client_connection_callback', $client_connection );
$this->redis = call_user_func_array( $client_connection, [ $client_parameters ] );
} catch ( Exception $e ) {
$this->_exception_handler( $e );
$this->is_redis_connected = false;
return $this->is_redis_connected;
}
$keys_methods = [
'auth' => 'auth',
'database' => 'select',
];
try {
$setup_connection = [ $this, 'perform_client_connection' ];
/**
* Permits alternate setup client connection mechanism to be used.
*
* @param callable $setup_connection Callback to execute.
*/
$setup_connection = apply_filters( 'wp_redis_perform_client_connection_callback', $setup_connection );
call_user_func_array( $setup_connection, [ $this->redis, $client_parameters, $keys_methods ] );
} catch ( Exception $e ) {
$this->_exception_handler( $e );
$this->is_redis_connected = false;
return $this->is_redis_connected;
}
$this->is_redis_connected = $this->redis->isConnected();
if ( ! $this->is_redis_connected ) {
$this->missing_redis_message = 'Warning! WP Redis object cache cannot connect to Redis server.';
}
return $this->is_redis_connected;
}
/**
* Are the required dependencies for connecting to Redis available?
*
* @return mixed True if the required dependencies are present, string if
* not with a message describing the issue.
*/
public function check_client_dependencies() {
if ( ! class_exists( 'Redis' ) ) {
return 'Warning! PHPRedis extension is unavailable, which is required by WP Redis object cache.';
}
return true;
}
/**
* Builds an array to be passed to a function that will set up the Redis
* client.
*
* @param array $redis_server Parameters used to construct a Redis client.
* @return array Final parameters to use to contruct a Redis client with
* with defaults applied.
*/
public function build_client_parameters( $redis_server ) {
if ( empty( $redis_server ) ) {
// Attempt to automatically load Pantheon's Redis config from the env.
if ( isset( $_SERVER['CACHE_HOST'] ) ) {
$redis_server = [
'host' => wp_strip_all_tags( $_SERVER['CACHE_HOST'] ),
'port' => isset( $_SERVER['CACHE_PORT'] ) ? wp_strip_all_tags( $_SERVER['CACHE_PORT'] ) : 0,
'auth' => isset( $_SERVER['CACHE_PASSWORD'] ) ? wp_strip_all_tags( $_SERVER['CACHE_PASSWORD'] ) : '',
'database' => isset( $_SERVER['CACHE_DB'] ) ? wp_strip_all_tags( $_SERVER['CACHE_DB'] ) : 0,
];
} else {
$redis_server = [
'host' => '127.0.0.1',
'port' => 6379,
'database' => 0,
];
}
}
if ( file_exists( $redis_server['host'] ) && 'socket' === filetype( $redis_server['host'] ) ) { // unix socket connection.
// port must be null or socket won't connect.
$port = null;
} else { // tcp connection.
$port = ! empty( $redis_server['port'] ) ? $redis_server['port'] : 6379;
}
$defaults = [
'host' => $redis_server['host'],
'port' => $port,
'timeout' => 1000, // I multiplied this by 1000 so we'd have a common measure of ms instead of s and ms, need to make sure this gets divided by 1000.
'retry_interval' => 100,
];
// 1s timeout, 100ms delay between reconnections.
// merging the defaults with the original $redis_server enables any custom parameters to get sent downstream to the redis client.
return array_replace_recursive( $redis_server, $defaults );
}
/**
* Constructs a PHPRedis Redis client.
*
* @param array $client_parameters Parameters used to construct a Redis client.
* @return Redis Redis client.
*/
public function prepare_client_connection( $client_parameters ) {
if ( defined( 'WP_REDIS_USE_RELAY' ) && WP_REDIS_USE_RELAY ) {
$redis = new Relay\Relay();
} else {
$redis = new Redis();
}
$redis->connect(
$client_parameters['host'],
$client_parameters['port'],
// $client_parameters['timeout'] is sent in milliseconds, connect() takes seconds, so divide by 1000.
$client_parameters['timeout'] / 1000,
null,
$client_parameters['retry_interval']
);
return $redis;
}
/**
* Sets up the Redis connection (ie authentication and specific database).
*
* @param Redis $redis Redis client.
* @param array $client_parameters Parameters used to configure Redis.
* @param array $keys_methods Associative array of keys from
* $client_parameters to use as method arguments for $redis.
* @throws Exception If the connection fails.
* @return bool True if successful.
*/
public function perform_client_connection( $redis, $client_parameters, $keys_methods ) {
foreach ( $keys_methods as $key => $method ) {
if ( ! isset( $client_parameters[ $key ] ) ) {
continue;
}
try {
$redis->$method( $client_parameters[ $key ] );
} catch ( RedisException $e ) {
// PhpRedis throws an Exception when it fails a server call.
// To prevent WordPress from fataling, we catch the Exception.
throw new Exception( $e->getMessage(), $e->getCode(), $e );
}
}
return true;
}
/**
* Wrapper method for calls to Redis, which fails gracefully when Redis is unavailable
*
* @param string $method The name of the Redis method to call.
* @throws Exception If the connection fails.
* @return mixed The return value of the Redis method, or false if Redis is unavailable.
*/
protected function _call_redis( $method ) {
global $wpdb;
$arguments = func_get_args();
array_shift( $arguments ); // ignore $method.
// $group is intended for the failback, and isn't passed to the Redis callback.
if ( 'hIncrBy' === $method ) {
$group = array_pop( $arguments );
}
if ( $this->is_redis_connected ) {
try {
if ( ! isset( $this->redis_calls[ $method ] ) ) {
$this->redis_calls[ $method ] = 0;
}
$this->redis_calls[ $method ]++;
$retval = call_user_func_array( [ $this->redis, $method ], $arguments );
return $retval;
} catch ( Exception $e ) {
$retry_exception_messages = $this->retry_exception_messages();
// PhpRedis throws an Exception when it fails a server call.
// To prevent WordPress from fataling, we catch the Exception.
if ( $this->exception_message_matches( $e->getMessage(), $retry_exception_messages ) ) {
$this->_exception_handler( $e );
// Attempt to refresh the connection if it was successfully established once $this->is_redis_connected will be set inside _connect_redis().
if ( $this->_connect_redis() ) {
return call_user_func_array( [ $this, '_call_redis' ], array_merge( [ $method ], $arguments ) );
}
// Fall through to fallback below.
} else {
throw $e;
}
}
} // End if.
if ( $this->is_redis_failback_flush_enabled() && ! $this->do_redis_failback_flush && ! empty( $wpdb ) ) {
if ( $this->multisite ) {
$table = $wpdb->sitemeta;
$col1 = 'meta_key';
$col2 = 'meta_value';
} else {
$table = $wpdb->options;
$col1 = 'option_name';
$col2 = 'option_value';
}
$wpdb->query( "INSERT IGNORE INTO {$table} ({$col1},{$col2}) VALUES ('wp_redis_do_redis_failback_flush',1)" );
$this->do_redis_failback_flush = true;
}
// Mock expected behavior from Redis for these methods.
switch ( $method ) {
case 'incr':
case 'incrBy':
$val = $this->cache[ $arguments[0] ];
$offset = isset( $arguments[1] ) && 'incrBy' === $method ? $arguments[1] : 1;
$val = $val + $offset;
return $val;
case 'hIncrBy':
$val = $this->_get_internal( $arguments[1], $group );
return $val + $arguments[2];
case 'decrBy':
case 'decr':
$val = $this->cache[ $arguments[0] ];
$offset = isset( $arguments[1] ) && 'decrBy' === $method ? $arguments[1] : 1;
$val = $val - $offset;
return $val;
case 'del':
case 'hDel':
return 1;
case 'flushAll':
case 'flushdb':
case 'IsConnected':
case 'exists':
case 'get':
case 'mget':
case 'hGet':
case 'hmGet':
return false;
}
}
/**
* Returns a filterable array of expected Exception messages that may be thrown
*
* @return array Array of expected exception messages
*/
public function retry_exception_messages() {
$retry_exception_messages = [ 'socket error on read socket', 'Connection closed', 'Redis server went away' ];
return apply_filters( 'wp_redis_retry_exception_messages', $retry_exception_messages );
}
/**
* Compares individual message to list of messages.
*
* @param string $error Message to compare
* @param array $errors Array of messages to compare to
* @return bool whether $error matches any items in $errors
*/
public function exception_message_matches( $error, $errors ) {
foreach ( $errors as $message ) {
$pattern = $this->_format_message_for_pattern( $message );
$matches = (bool) preg_match( $pattern, $error );
if ( $matches ) {
return true;
}
}
return false;
}
/**
* Prepends and appends '/' if not present in a string
*
* @param string $message Potential regex string that may need '/'
* @return string Regex pattern
*/
protected function _format_message_for_pattern( $message ) {
$var = $message;
$var = '/' === $var[0] ? $var : '/' . $var;
$var = '/' === $var[ strlen( $var ) - 1 ] ? $var : $var . '/';
return $var;
}
/**
* Handles exceptions by triggering a php error.
*
* @param Exception $exception The exception to handle.
* @return void
*/
protected function _exception_handler( $exception ) {
try {
$this->last_triggered_error = 'WP Redis: ' . $exception->getMessage();
// Be friendly to developers debugging production servers by triggering an error.
trigger_error( esc_html( $this->last_triggered_error ), E_USER_WARNING ); // phpcs:ignore WordPress.PHP.DevelopmentFunctions.error_log_trigger_error
} catch ( PHPUnit_Framework_Error_Warning $e ) { // phpcs:ignore Generic.CodeAnalysis.EmptyStatement.DetectedCatch
// PHPUnit throws an Exception when `trigger_error()` is called. To ensure our tests (which expect Exceptions to be caught) continue to run, we catch the PHPUnit exception and inspect the RedisException message.
}
}
/**
* Admin UI to let the end user know something about the Redis connection isn't working.
*/
public function wp_action_admin_notices_warn_missing_redis() {
if ( ! current_user_can( 'manage_options' ) || empty( $this->missing_redis_message ) ) {
return;
}
echo '<div class="message error"><p>' . esc_html( $this->missing_redis_message ) . '</p></div>';
}
/**
* Whether or not wakeup flush is enabled
*
* @return bool
*/
private function is_redis_failback_flush_enabled() {
if ( defined( 'WP_INSTALLING' ) && WP_INSTALLING ) {
return false;
} elseif ( defined( 'WP_REDIS_DISABLE_FAILBACK_FLUSH' ) && WP_REDIS_DISABLE_FAILBACK_FLUSH ) {
return false;
}
return true;
}
/**
* Sets up object properties; PHP 5 style constructor
*/
public function __construct() {
global $blog_id, $table_prefix, $wpdb;
$this->multisite = is_multisite();
$this->blog_prefix = $this->multisite ? $blog_id . ':' : '';
if ( ! $this->_connect_redis() && function_exists( 'add_action' ) ) {
add_action( 'admin_notices', [ $this, 'wp_action_admin_notices_warn_missing_redis' ] );
}
if ( $this->is_redis_failback_flush_enabled() && ! empty( $wpdb ) ) {
if ( $this->multisite ) {
$table = $wpdb->sitemeta;
$col1 = 'meta_key';
$col2 = 'meta_value';
} else {
$table = $wpdb->options;
$col1 = 'option_name';
$col2 = 'option_value';
}
$this->do_redis_failback_flush = (bool) $wpdb->get_results( "SELECT {$col2} FROM {$table} WHERE {$col1}='wp_redis_do_redis_failback_flush'" );
if ( $this->is_redis_connected && $this->do_redis_failback_flush ) {
$ret = $this->_call_redis( 'flushdb' );
if ( $ret ) {
$wpdb->query( "DELETE FROM {$table} WHERE {$col1}='wp_redis_do_redis_failback_flush'" );
$this->do_redis_failback_flush = false;
}
}
}
$this->global_prefix = ( $this->multisite || defined( 'CUSTOM_USER_TABLE' ) && defined( 'CUSTOM_USER_META_TABLE' ) ) ? '' : $table_prefix;
// @todo This should be moved to the PHP4 style constructor, PHP5
register_shutdown_function( [ $this, '__destruct' ] );
}
/**
* Will save the object cache before object is completely destroyed.
*
* Called upon object destruction, which should be when PHP ends.
*
* @return bool True value. Won't be used by PHP
*/
public function __destruct() {
return true;
}
}