Class yii\caching\MemCache
| Inheritance | yii\caching\MemCache » yii\caching\Cache » yii\base\Component » yii\base\BaseObject |
|---|---|
| Implements | yii\base\Configurable, yii\caching\CacheInterface |
| Available since version | 2.0 |
| Source Code | https://github.com/yiisoft/yii2/blob/master/framework/caching/MemCache.php |
MemCache implements a cache application component based on memcache and memcached.
MemCache supports both memcache and memcached. By setting $useMemcached to be true or false, one can let MemCache to use either memcached or memcache, respectively.
MemCache can be configured with a list of memcache servers by settings its \yii\caching\servers property. By default, MemCache assumes there is a memcache server running on localhost at port 11211.
See yii\caching\Cache for common cache operations that MemCache supports.
Note, there is no security measure to protected data in memcache. All data in memcache can be accessed by any process running in the system.
To use MemCache as the cache application component, configure the application as follows,
[
'components' => [
'cache' => [
'class' => 'yii\caching\MemCache',
'servers' => [
[
'host' => 'server1',
'port' => 11211,
'weight' => 60,
],
[
'host' => 'server2',
'port' => 11211,
'weight' => 40,
],
],
],
],
]
In the above, two memcache servers are used: server1 and server2. You can configure more properties of
each server, such as persistent, weight, timeout. Please see yii\caching\MemCacheServer for available options.
For more details and usage information on Cache, see the guide article on caching.
Public Properties
| Property | Type | Description | Defined By |
|---|---|---|---|
| $defaultDuration | integer | Default duration in seconds before a cache entry will expire. | yii\caching\Cache |
| $keyPrefix | string | A string prefixed to every cache key so that it is unique globally in the whole cache storage. | yii\caching\Cache |
| $options | array | Options for Memcached. | yii\caching\MemCache |
| $password | string | Memcached sasl password. | yii\caching\MemCache |
| $persistentId | string | An ID that identifies a Memcached instance. | yii\caching\MemCache |
| $serializer | null|array|false | The functions used to serialize and unserialize cached data. | yii\caching\Cache |
| $useMemcached | boolean | Whether to use memcached or memcache as the underlying caching extension. | yii\caching\MemCache |
| $username | string | Memcached sasl username. | yii\caching\MemCache |
Public Methods
| Method | Description | Defined By |
|---|---|---|
| __call() | Calls the named method which is not a class method. | yii\base\Component |
| __clone() | This method is called after the object is created by cloning an existing one. | yii\base\Component |
| __construct() | Constructor. | yii\base\BaseObject |
| __get() | Returns the value of a component property. | yii\base\Component |
| __isset() | Checks if a property is set, i.e. defined and not null. | yii\base\Component |
| __set() | Sets the value of a component property. | yii\base\Component |
| __unset() | Sets a component property to be null. | yii\base\Component |
| add() | Stores a value identified by a key into cache if the cache does not contain this key. | yii\caching\Cache |
| attachBehavior() | Attaches a behavior to this component. | yii\base\Component |
| attachBehaviors() | Attaches a list of behaviors to the component. | yii\base\Component |
| behaviors() | Returns a list of behaviors that this component should behave as. | yii\base\Component |
| buildKey() | Builds a normalized cache key from a given key. | yii\caching\Cache |
| canGetProperty() | Returns a value indicating whether a property can be read. | yii\base\Component |
| canSetProperty() | Returns a value indicating whether a property can be set. | yii\base\Component |
| className() | Returns the fully qualified name of this class. | yii\base\BaseObject |
| delete() | Deletes a value with the specified key from cache. | yii\caching\Cache |
| detachBehavior() | Detaches a behavior from the component. | yii\base\Component |
| detachBehaviors() | Detaches all behaviors from the component. | yii\base\Component |
| ensureBehaviors() | Makes sure that the behaviors declared in behaviors() are attached to this component. | yii\base\Component |
| exists() | Checks whether a specified key exists in the cache. | yii\caching\Cache |
| flush() | Deletes all values from cache. | yii\caching\Cache |
| get() | Retrieves a value from cache with a specified key. | yii\caching\Cache |
| getBehavior() | Returns the named behavior object. | yii\base\Component |
| getBehaviors() | Returns all behaviors attached to this component. | yii\base\Component |
| getMemcache() | Returns the underlying memcache (or memcached) object. | yii\caching\MemCache |
| getOrSet() | Method combines both set() and get() methods to retrieve value identified by a $key, or to store the result of $callable execution if there is no cache available for the $key. | yii\caching\Cache |
| getServers() | Returns the memcache or memcached server configurations. | yii\caching\MemCache |
| hasEventHandlers() | Returns a value indicating whether there is any handler attached to the named event. | yii\base\Component |
| hasMethod() | Returns a value indicating whether a method is defined. | yii\base\Component |
| hasProperty() | Returns a value indicating whether a property is defined for this component. | yii\base\Component |
| init() | Initializes this application component. | yii\caching\MemCache |
| madd() | Stores multiple items in cache. Each item contains a value identified by a key. | yii\caching\Cache |
| mget() | Retrieves multiple values from cache with the specified keys. | yii\caching\Cache |
| mset() | Stores multiple items in cache. Each item contains a value identified by a key. | yii\caching\Cache |
| multiAdd() | Stores multiple items in cache. Each item contains a value identified by a key. | yii\caching\Cache |
| multiGet() | Retrieves multiple values from cache with the specified keys. | yii\caching\Cache |
| multiSet() | Stores multiple items in cache. Each item contains a value identified by a key. | yii\caching\Cache |
| off() | Detaches an existing event handler from this component. | yii\base\Component |
| offsetExists() | Returns whether there is a cache entry with a specified key. | yii\caching\Cache |
| offsetGet() | Retrieves the value from cache with a specified key. | yii\caching\Cache |
| offsetSet() | Stores the value identified by a key into cache. | yii\caching\Cache |
| offsetUnset() | Deletes the value with the specified key from cache This method is required by the interface ArrayAccess. | yii\caching\Cache |
| on() | Attaches an event handler to an event. | yii\base\Component |
| set() | Stores a value identified by a key into cache. | yii\caching\Cache |
| setServers() | yii\caching\MemCache | |
| trigger() | Triggers an event. | yii\base\Component |
Protected Methods
| Method | Description | Defined By |
|---|---|---|
| addMemcacheServers() | Add servers to the server pool of the cache specified Used for memcache PECL extension. | yii\caching\MemCache |
| addMemcachedServers() | Add servers to the server pool of the cache specified Used for memcached PECL extension. | yii\caching\MemCache |
| addServers() | Add servers to the server pool of the cache specified. | yii\caching\MemCache |
| addValue() | Stores a value identified by a key into cache if the cache does not contain this key. | yii\caching\MemCache |
| addValues() | Adds multiple key-value pairs to cache. | yii\caching\Cache |
| deleteValue() | Deletes a value with the specified key from cache This is the implementation of the method declared in the parent class. | yii\caching\MemCache |
| flushValues() | Deletes all values from cache. | yii\caching\MemCache |
| getValue() | Retrieves a value from cache with a specified key. | yii\caching\MemCache |
| getValues() | Retrieves multiple values from cache with the specified keys. | yii\caching\MemCache |
| normalizeDuration() | Normalizes duration value | yii\caching\MemCache |
| setValue() | Stores a value identified by a key in cache. | yii\caching\MemCache |
| setValues() | Stores multiple key-value pairs in cache. | yii\caching\MemCache |
Property Details
Options for Memcached. This property is used only when $useMemcached is true.
See also https://secure.php.net/manual/en/memcached.setoptions.php.
Memcached sasl password. This property is used only when $useMemcached is true.
See also https://secure.php.net/manual/en/memcached.setsaslauthdata.php.
An ID that identifies a Memcached instance. This property is used only when $useMemcached is true. By default the Memcached instances are destroyed at the end of the request. To create an instance that persists between requests, you may specify a unique ID for the instance. All instances created with the same ID will share the same connection.
See also https://secure.php.net/manual/en/memcached.construct.php.
Whether to use memcached or memcache as the underlying caching extension. If true, memcached will be used. If false, memcache will be used. Defaults to false.
Memcached sasl username. This property is used only when $useMemcached is true.
See also https://secure.php.net/manual/en/memcached.setsaslauthdata.php.
Method Details
Add servers to the server pool of the cache specified Used for memcache PECL extension.
| protected void addMemcacheServers ( $cache, $servers ) | ||
| $cache | \Memcache | |
| $servers | yii\caching\MemCacheServer[] | |
Add servers to the server pool of the cache specified Used for memcached PECL extension.
| protected void addMemcachedServers ( $cache, $servers ) | ||
| $cache | \Memcached | |
| $servers | yii\caching\MemCacheServer[] | |
Add servers to the server pool of the cache specified.
| protected void addServers ( $cache, $servers ) | ||
| $cache | \Memcache|\Memcached | |
| $servers | yii\caching\MemCacheServer[] | |
| throws | yii\base\InvalidConfigException | |
|---|---|---|
Stores a value identified by a key into cache if the cache does not contain this key.
This is the implementation of the method declared in the parent class.
See also Memcache::set().
| protected boolean addValue ( $key, $value, $duration ) | ||
| $key | string | The key identifying the value to be cached |
| $value | mixed | The value to be cached |
| $duration | integer | The number of seconds in which the cached value will expire. 0 means never expire. |
| return | boolean | True if the value is successfully stored into cache, false otherwise |
|---|---|---|
Deletes a value with the specified key from cache This is the implementation of the method declared in the parent class.
| protected boolean deleteValue ( $key ) | ||
| $key | string | The key of the value to be deleted |
| return | boolean | If no error happens during deletion |
|---|---|---|
Deletes all values from cache.
This is the implementation of the method declared in the parent class.
| protected boolean flushValues ( ) | ||
| return | boolean | Whether the flush operation was successful. |
|---|---|---|
Returns the underlying memcache (or memcached) object.
| public \Memcache|\Memcached getMemcache ( ) | ||
| return | \Memcache|\Memcached | The memcache (or memcached) object used by this cache component. |
|---|---|---|
| throws | yii\base\InvalidConfigException | if memcache or memcached extension is not loaded |
Returns the memcache or memcached server configurations.
| public yii\caching\MemCacheServer[] getServers ( ) | ||
| return | yii\caching\MemCacheServer[] | List of memcache server configurations. |
|---|---|---|
Retrieves a value from cache with a specified key.
This is the implementation of the method declared in the parent class.
| protected mixed|false getValue ( $key ) | ||
| $key | string | A unique key identifying the cached value |
| return | mixed|false | The value stored in cache, false if the value is not in the cache or expired. |
|---|---|---|
Retrieves multiple values from cache with the specified keys.
| protected array getValues ( $keys ) | ||
| $keys | array | A list of keys identifying the cached values |
| return | array | A list of cached values indexed by the keys |
|---|---|---|
Initializes this application component.
It creates the memcache instance and adds memcache servers.
| public void init ( ) |
Normalizes duration value
See also:
| protected integer normalizeDuration ( $duration ) | ||
| $duration | integer | |
See also:
| public void setServers ( $config ) | ||
| $config | array | List of memcache or memcached server configurations. Each element must be an array with the following keys: host, port, persistent, weight, timeout, retryInterval, status. |
Stores a value identified by a key in cache.
This is the implementation of the method declared in the parent class.
See also Memcache::set().
| protected boolean setValue ( $key, $value, $duration ) | ||
| $key | string | The key identifying the value to be cached |
| $value | mixed | The value to be cached. |
| $duration | integer | The number of seconds in which the cached value will expire. 0 means never expire. |
| return | boolean | True if the value is successfully stored into cache, false otherwise |
|---|---|---|
Stores multiple key-value pairs in cache.
| protected array setValues ( $data, $duration ) | ||
| $data | array | Array where key corresponds to cache key while value is the value stored |
| $duration | integer | The number of seconds in which the cached values will expire. 0 means never expire. |
| return | array | Array of failed keys. |
|---|---|---|