HumHub Documentation (unofficial)

Cache extends Component
in package

Application

implements CacheInterface

AbstractYes

Cache is the base class for cache classes supporting different cache storage implementations.

A data item can be stored in the cache by calling [[set()]] and be retrieved back later (in the same or different request) by [[get()]]. In both operations, a key identifying the data item is required. An expiration time and/or a [[Dependency|dependency]] can also be specified when calling [[set()]]. If the data item expires or the dependency changes at the time of calling [[get()]], the cache will return no data.

A typical usage pattern of cache is like the following:

$key = 'demo';
$data = $cache->get($key);
if ($data === false) {
    // ...generate $data here...
    $cache->set($key, $data, $duration, $dependency);
}

Because Cache implements the [[\ArrayAccess]] interface, it can be used like an array. For example,

$cache['foo'] = 'some data';
echo $cache['foo'];

Derived classes should implement the following methods which do the actual cache storage operations:

[[getValue()]]: retrieve the value with a key (if any) from cache
[[setValue()]]: store the value with a key into cache
[[addValue()]]: store the value only if the cache does not have this key before
[[deleteValue()]]: delete the value with the specified key from cache
[[flushValues()]]: delete all values from cache

For more details and usage information on Cache, see the guide article on caching.

Interfaces

CacheInterface: CacheInterface is the base interface for cache.

Properties

$behaviors : array<string|int, Behavior>
$defaultDuration : int
$keyPrefix : string
$serializer : array<string|int, mixed>|null|false
$_behaviors : array<string|int, Behavior>|null
$_events : array<string|int, mixed>
$_eventWildcards : array<string|int, mixed>
$_igbinaryAvailable : bool

Methods

__call() : mixed: Calls the named method which is not a class method.
__clone() : mixed: This method is called after the object is created by cloning an existing one.
__construct() : mixed: Constructor.
__get() : mixed: Returns the value of a component property.
__isset() : bool: Checks if a property is set, i.e. defined and not null.
__set() : mixed: Sets the value of a component property.
__unset() : mixed: Sets a component property to be null.
add() : bool: Stores a value identified by a key into cache if the cache does not contain this key.
attachBehavior() : Behavior: Attaches a behavior to this component.
attachBehaviors() : mixed: Attaches a list of behaviors to the component.
behaviors() : array<string|int, mixed>: Returns a list of behaviors that this component should behave as.
buildKey() : string: Builds a normalized cache key from a given key.
canGetProperty() : bool: Returns a value indicating whether a property can be read.
canSetProperty() : bool: Returns a value indicating whether a property can be set.
className() : string: Returns the fully qualified name of this class.
delete() : bool: Deletes a value with the specified key from cache.
detachBehavior() : Behavior|null: Detaches a behavior from the component.
detachBehaviors() : mixed: Detaches all behaviors from the component.
ensureBehaviors() : mixed: Makes sure that the behaviors declared in [[behaviors()]] are attached to this component.
exists() : bool: Checks whether a specified key exists in the cache.
flush() : bool: Deletes all values from cache.
get() : mixed: Retrieves a value from cache with a specified key.
getBehavior() : Behavior|null: Returns the named behavior object.
getBehaviors() : array<string|int, Behavior>: Returns all behaviors attached to this component.
getOrSet() : mixed: 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.
hasEventHandlers() : bool: Returns a value indicating whether there is any handler attached to the named event.
hasMethod() : bool: Returns a value indicating whether a method is defined.
hasProperty() : bool: Returns a value indicating whether a property is defined for this component.
init() : mixed: Initializes the object.
madd() : array<string|int, mixed>: Stores multiple items in cache. Each item contains a value identified by a key.
mget() : array<string|int, mixed>: Retrieves multiple values from cache with the specified keys.
mset() : array<string|int, mixed>: Stores multiple items in cache. Each item contains a value identified by a key.
multiAdd() : array<string|int, mixed>: Stores multiple items in cache. Each item contains a value identified by a key.
multiGet() : array<string|int, mixed>: Retrieves multiple values from cache with the specified keys.
multiSet() : array<string|int, mixed>: Stores multiple items in cache. Each item contains a value identified by a key.
off() : bool: Detaches an existing event handler from this component.
offsetExists() : bool: Returns whether there is a cache entry with a specified key.
offsetGet() : mixed: Retrieves the value from cache with a specified key.
offsetSet() : mixed: Stores the value identified by a key into cache.
offsetUnset() : mixed: Deletes the value with the specified key from cache This method is required by the interface [[\ArrayAccess]].
on() : mixed: Attaches an event handler to an event.
set() : bool: Stores a value identified by a key into cache.
trigger() : mixed: Triggers an event.
addValue() : bool: Stores a value identified by a key into cache if the cache does not contain this key.
addValues() : array<string|int, mixed>: Adds multiple key-value pairs to cache.
deleteValue() : bool: Deletes a value with the specified key from cache This method should be implemented by child classes to delete the data from actual cache storage.
flushValues() : bool: Deletes all values from cache.
getValue() : mixed|false: Retrieves a value from cache with a specified key.
getValues() : array<string|int, mixed>: Retrieves multiple values from cache with the specified keys.
setValue() : bool: Stores a value identified by a key in cache.
setValues() : array<string|int, mixed>: Stores multiple key-value pairs in cache.
attachBehaviorInternal() : Behavior: Attaches a behavior to this component.
prepareCacheData() : array<string|int, mixed>: Prepares data for caching by serializing values and evaluating dependencies.

$behaviors read-only


    public
        array<string|int, Behavior>
    $behaviors

List of behaviors attached to this component.

$defaultDuration


    public
        int
    $defaultDuration
     = 0

default duration in seconds before a cache entry will expire. Default value is 0, meaning infinity. This value is used by [[set()]] if the duration is not explicitly given.

$keyPrefix


    public
        string
    $keyPrefix

a string prefixed to every cache key so that it is unique globally in the whole cache storage. It is recommended that you set a unique cache key prefix for each application if the same cache storage is being used by different applications.

To ensure interoperability, only alphanumeric characters should be used.

$serializer


    public
        array<string|int, mixed>|null|false
    $serializer

the functions used to serialize and unserialize cached data. Defaults to null, meaning using the default PHP serialize() and unserialize() functions. If you want to use some more efficient serializer (e.g. igbinary), you may configure this property with a two-element array. The first element specifies the serialization function, and the second the deserialization function. If this property is set false, data will be directly sent to and retrieved from the underlying cache component without any serialization or deserialization. You should not turn off serialization if you are using [[Dependency|cache dependency]], because it relies on data serialization. Also, some implementations of the cache can not correctly save and retrieve data different from a string type.

$_behaviors


    private
        array<string|int, Behavior>|null
    $_behaviors

the attached behaviors (behavior name => behavior). This is null when not initialized.

$_events


    private
        array<string|int, mixed>
    $_events
     = []

the attached event handlers (event name => handlers)

$_eventWildcards


    private
        array<string|int, mixed>
    $_eventWildcards
     = []

the event handlers attached for wildcard patterns (event name wildcard => handlers)

$_igbinaryAvailable


    private
        bool
    $_igbinaryAvailable
     = false

whether igbinary serialization is available or not.

__call()

Calls the named method which is not a class method.


    public
                    __call(string $name, array<string|int, mixed> $params) : mixed

This method will check if any attached behavior has the named method and will execute it if available.

Do not call this method directly as it is a PHP magic method that will be implicitly called when an unknown method is being invoked.

Parameters

$name : string: the method name
$params : array<string|int, mixed>: method parameters

Return values

mixed —

the method return value

__clone()

This method is called after the object is created by cloning an existing one.


    public
                    __clone() : mixed

It removes all behaviors because they are attached to the old object.

__construct()

Constructor.


    public
                    __construct([array<string|int, mixed> $config = [] ]) : mixed

The default implementation does two things:

Initializes the object with the given configuration $config.
Call [[init()]].

If this method is overridden in a child class, it is recommended that

the last parameter of the constructor is a configuration array, like $config here.
call the parent implementation at the end of the constructor.

Parameters

$config : array<string|int, mixed> = []: name-value pairs that will be used to initialize the object properties

__get()

Returns the value of a component property.


    public
                    __get(string $name) : mixed

This method will check in the following order and act accordingly:

a property defined by a getter: return the getter result
a property of a behavior: return the behavior property value

Do not call this method directly as it is a PHP magic method that will be implicitly called when executing $value = $component->property;.

Parameters

$name : string: the property name

Return values

mixed —

the property value or the value of a behavior's property

__isset()

Checks if a property is set, i.e. defined and not null.


    public
                    __isset(string $name) : bool

This method will check in the following order and act accordingly:

a property defined by a setter: return whether the property is set
a property of a behavior: return whether the property is set
return false for non existing properties

Do not call this method directly as it is a PHP magic method that will be implicitly called when executing isset($component->property).

Parameters

$name : string: the property name or the event name

Return values

bool —

whether the named property is set

__set()

Sets the value of a component property.


    public
                    __set(string $name, mixed $value) : mixed

This method will check in the following order and act accordingly:

a property defined by a setter: set the property value
an event in the format of "on xyz": attach the handler to the event "xyz"
a behavior in the format of "as xyz": attach the behavior named as "xyz"
a property of a behavior: set the behavior property value

Do not call this method directly as it is a PHP magic method that will be implicitly called when executing $component->property = $value;.

Parameters

$name : string: the property name or the event name
$value : mixed: the property value

__unset()

Sets a component property to be null.


    public
                    __unset(string $name) : mixed

This method will check in the following order and act accordingly:

a property defined by a setter: set the property value to be null
a property of a behavior: set the property value to be null

Do not call this method directly as it is a PHP magic method that will be implicitly called when executing unset($component->property).

Parameters

$name : string: the property name

add()

Stores a value identified by a key into cache if the cache does not contain this key.


    public
                    add(mixed $key, mixed $value[, int $duration = 0 ][, Dependency|null $dependency = null ]) : bool

Nothing will be done if the cache already contains the key.

Parameters

$key : mixed: a key identifying the value to be cached. This can be a simple string or a complex data structure consisting of factors representing the key.
$value : mixed: the value to be cached
$duration : int = 0: the number of seconds in which the cached value will expire. 0 means never expire.
$dependency : Dependency|null = null: dependency of the cached item. If the dependency changes, the corresponding value in the cache will be invalidated when it is fetched via [[get()]]. This parameter is ignored if [[serializer]] is false.

Return values

bool —

whether the value is successfully stored into cache

attachBehavior()

Attaches a behavior to this component.


    public
                    attachBehavior(string $name, string|array<string|int, mixed>|Behavior $behavior) : Behavior

This method will create the behavior object based on the given configuration. After that, the behavior object will be attached to this component by calling the [[Behavior::attach()]] method.

Parameters

$name : string

the name of the behavior.

$behavior : string|array<string|int, mixed>|Behavior

the behavior configuration. This can be one of the following:

a [[Behavior]] object
a string specifying the behavior class
an object configuration array that will be passed to [[Yii::createObject()]] to create the behavior object.

Return values

Behavior —

the behavior object

attachBehaviors()

Attaches a list of behaviors to the component.


    public
                    attachBehaviors(array<string|int, mixed> $behaviors) : mixed

Each behavior is indexed by its name and should be a [[Behavior]] object, a string specifying the behavior class, or an configuration array for creating the behavior.

Parameters

$behaviors : array<string|int, mixed>: list of behaviors to be attached to the component

behaviors()

Returns a list of behaviors that this component should behave as.


    public
                    behaviors() : array<string|int, mixed>

Child classes may override this method to specify the behaviors they want to behave as.

The return value of this method should be an array of behavior objects or configurations indexed by behavior names. A behavior configuration can be either a string specifying the behavior class or an array of the following structure:

'behaviorName' => [
    'class' => 'BehaviorClass',
    'property1' => 'value1',
    'property2' => 'value2',
]

Note that a behavior class must extend from [[Behavior]]. Behaviors can be attached using a name or anonymously. When a name is used as the array key, using this name, the behavior can later be retrieved using [[getBehavior()]] or be detached using [[detachBehavior()]]. Anonymous behaviors can not be retrieved or detached.

Behaviors declared in this method will be attached to the component automatically (on demand).

Return values

array<string|int, mixed> —

the behavior configurations.

buildKey()

Builds a normalized cache key from a given key.


    public
                    buildKey(mixed $key) : string

If the given key is a string containing alphanumeric characters only and no more than 32 characters, then the key will be returned back prefixed with [[keyPrefix]]. Otherwise, a normalized key is generated by serializing the given key, applying MD5 hashing, and prefixing with [[keyPrefix]].

Parameters

$key : mixed: the key to be normalized

Return values

string —

the generated cache key

canGetProperty()

Returns a value indicating whether a property can be read.


    public
                    canGetProperty(string $name[, bool $checkVars = true ][, bool $checkBehaviors = true ]) : bool

A property can be read if:

the class has a getter method associated with the specified name (in this case, property name is case-insensitive);
the class has a member variable with the specified name (when $checkVars is true);
an attached behavior has a readable property of the given name (when $checkBehaviors is true).

Parameters

$name : string: the property name
$checkVars : bool = true: whether to treat member variables as properties
$checkBehaviors : bool = true: whether to treat behaviors' properties as properties of this component

Return values

bool —

whether the property can be read

canSetProperty()

Returns a value indicating whether a property can be set.


    public
                    canSetProperty(string $name[, bool $checkVars = true ][, bool $checkBehaviors = true ]) : bool

A property can be written if:

the class has a setter method associated with the specified name (in this case, property name is case-insensitive);
the class has a member variable with the specified name (when $checkVars is true);
an attached behavior has a writable property of the given name (when $checkBehaviors is true).

Parameters

$name : string: the property name
$checkVars : bool = true: whether to treat member variables as properties
$checkBehaviors : bool = true: whether to treat behaviors' properties as properties of this component

Return values

bool —

whether the property can be written

className()

Returns the fully qualified name of this class.


    public
            static        className() : string

Return values

string —

the fully qualified name of this class.

delete()

Deletes a value with the specified key from cache.


    public
                    delete(mixed $key) : bool

Parameters

$key : mixed: a key identifying the value to be deleted from cache. This can be a simple string or a complex data structure consisting of factors representing the key.

Return values

bool —

if no error happens during deletion

detachBehavior()

Detaches a behavior from the component.


    public
                    detachBehavior(string $name) : Behavior|null

The behavior's [[Behavior::detach()]] method will be invoked.

Parameters

$name : string: the behavior's name.

Return values

Behavior|null —

the detached behavior. Null if the behavior does not exist.

detachBehaviors()

Detaches all behaviors from the component.


    public
                    detachBehaviors() : mixed

ensureBehaviors()

Makes sure that the behaviors declared in [[behaviors()]] are attached to this component.


    public
                    ensureBehaviors() : mixed

exists()

Checks whether a specified key exists in the cache.


    public
                    exists(mixed $key) : bool

This can be faster than getting the value from the cache if the data is big. In case a cache does not support this feature natively, this method will try to simulate it but has no performance improvement over getting it. Note that this method does not check whether the dependency associated with the cached data, if there is any, has changed. So a call to [[get]] may return false while exists returns true.

Parameters

$key : mixed: a key identifying the cached value. This can be a simple string or a complex data structure consisting of factors representing the key.

Return values

bool —

true if a value exists in cache, false if the value is not in the cache or expired.

flush()

Deletes all values from cache.


    public
                    flush() : bool

Be careful of performing this operation if the cache is shared among multiple applications.

Return values

bool —

whether the flush operation was successful.

get()

Retrieves a value from cache with a specified key.


    public
                    get(mixed $key) : mixed

Parameters

$key : mixed: a key identifying the cached value. This can be a simple string or a complex data structure consisting of factors representing the key.

Return values

mixed —

the value stored in cache, false if the value is not in the cache, expired, or the dependency associated with the cached data has changed.

getBehavior()

Returns the named behavior object.


    public
                    getBehavior(string $name) : Behavior|null

Parameters

$name : string: the behavior name

Return values

Behavior|null —

the behavior object, or null if the behavior does not exist

getBehaviors()

Returns all behaviors attached to this component.


    public
                    getBehaviors() : array<string|int, Behavior>

Return values

array<string|int, Behavior> —

list of behaviors attached to this component

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.


    public
                    getOrSet(mixed $key, callable|Closure $callable[, int|null $duration = null ][, Dependency|null $dependency = null ]) : mixed

Usage example:

public function getTopProducts($count = 10) {
    $cache = $this->cache; // Could be Yii::$app->cache
    return $cache->getOrSet(['top-n-products', 'n' => $count], function () use ($count) {
        return Products::find()->mostPopular()->limit($count)->all();
    }, 1000);
}

Parameters

$key : mixed: a key identifying the value to be cached. This can be a simple string or a complex data structure consisting of factors representing the key.
$callable : callable|Closure: the callable or closure that will be used to generate a value to be cached. If you use $callable that can return false, then keep in mind that [[getOrSet()]] may work inefficiently because the [[yii\caching\Cache::get()]] method uses false return value to indicate the data item is not found in the cache. Thus, caching of false value will lead to unnecessary internal calls.
$duration : int|null = null: default duration in seconds before the cache will expire. If not set, [[defaultDuration]] value will be used.
$dependency : Dependency|null = null: dependency of the cached item. If the dependency changes, the corresponding value in the cache will be invalidated when it is fetched via [[get()]]. This parameter is ignored if [[serializer]] is false.

Return values

mixed —

result of $callable execution

hasEventHandlers()

Returns a value indicating whether there is any handler attached to the named event.


    public
                    hasEventHandlers(string $name) : bool

Parameters

$name : string: the event name

Return values

bool —

whether there is any handler attached to the event.

hasMethod()

Returns a value indicating whether a method is defined.


    public
                    hasMethod(string $name[, bool $checkBehaviors = true ]) : bool

A method is defined if:

the class has a method with the specified name
an attached behavior has a method with the given name (when $checkBehaviors is true).

Parameters

$name : string: the property name
$checkBehaviors : bool = true: whether to treat behaviors' methods as methods of this component

Return values

bool —

whether the method is defined

hasProperty()

Returns a value indicating whether a property is defined for this component.


    public
                    hasProperty(string $name[, bool $checkVars = true ][, bool $checkBehaviors = true ]) : bool

A property is defined if:

the class has a getter or setter method associated with the specified name (in this case, property name is case-insensitive);
the class has a member variable with the specified name (when $checkVars is true);
an attached behavior has a property of the given name (when $checkBehaviors is true).

Parameters

$name : string: the property name
$checkVars : bool = true: whether to treat member variables as properties
$checkBehaviors : bool = true: whether to treat behaviors' properties as properties of this component

Return values

bool —

whether the property is defined

init()

Initializes the object.


    public
                    init() : mixed

madd()

Stores multiple items in cache. Each item contains a value identified by a key.


    public
                    madd(array<string|int, mixed> $items[, int $duration = 0 ][, Dependency|null $dependency = null ]) : array<string|int, mixed>

If the cache already contains such a key, the existing value and expiration time will be preserved.

Parameters

$items : array<string|int, mixed>: the items to be cached, as key-value pairs.
$duration : int = 0: default number of seconds in which the cached values will expire. 0 means never expire.
$dependency : Dependency|null = null: dependency of the cached items. If the dependency changes, the corresponding values in the cache will be invalidated when it is fetched via [[get()]]. This parameter is ignored if [[serializer]] is false.

Return values

array<string|int, mixed> —

array of failed keys

mget()

Retrieves multiple values from cache with the specified keys.


    public
                    mget(array<string|int, string> $keys) : array<string|int, mixed>

Some caches (such as memcache, apc) allow retrieving multiple cached values at the same time, which may improve the performance. In case a cache does not support this feature natively, this method will try to simulate it.

Parameters

$keys : array<string|int, string>: list of string keys identifying the cached values

Return values

array<string|int, mixed> —

list of cached values corresponding to the specified keys. The array is returned in terms of (key, value) pairs. If a value is not cached or expired, the corresponding array value will be false.

mset()

Stores multiple items in cache. Each item contains a value identified by a key.


    public
                    mset(array<string|int, mixed> $items[, int|null $duration = null ][, Dependency|null $dependency = null ]) : array<string|int, mixed>

If the cache already contains such a key, the existing value and expiration time will be replaced with the new ones, respectively.

Parameters

$items : array<string|int, mixed>: the items to be cached, as key-value pairs.
$duration : int|null = null: default duration in seconds before the cache will expire. If not set, default [[defaultDuration]] value is used.
$dependency : Dependency|null = null: dependency of the cached items. If the dependency changes, the corresponding values in the cache will be invalidated when it is fetched via [[get()]]. This parameter is ignored if [[serializer]] is false.

Return values

array<string|int, mixed> —

array of failed keys

multiAdd()

Stores multiple items in cache. Each item contains a value identified by a key.


    public
                    multiAdd(array<string|int, mixed> $items[, int $duration = 0 ][, Dependency|null $dependency = null ]) : array<string|int, mixed>

If the cache already contains such a key, the existing value and expiration time will be preserved.

Parameters

$items : array<string|int, mixed>: the items to be cached, as key-value pairs.
$duration : int = 0: default number of seconds in which the cached values will expire. 0 means never expire.
$dependency : Dependency|null = null: dependency of the cached items. If the dependency changes, the corresponding values in the cache will be invalidated when it is fetched via [[get()]]. This parameter is ignored if [[serializer]] is false.

Return values

array<string|int, mixed> —

array of failed keys

multiGet()

Retrieves multiple values from cache with the specified keys.


    public
                    multiGet(array<string|int, string> $keys) : array<string|int, mixed>

Parameters

$keys : array<string|int, string>: list of string keys identifying the cached values

Return values

array<string|int, mixed> —

list of cached values corresponding to the specified keys. The array is returned in terms of (key, value) pairs. If a value is not cached or expired, the corresponding array value will be false.

multiSet()

Stores multiple items in cache. Each item contains a value identified by a key.


    public
                    multiSet(array<string|int, mixed> $items[, int|null $duration = null ][, Dependency|null $dependency = null ]) : array<string|int, mixed>

If the cache already contains such a key, the existing value and expiration time will be replaced with the new ones, respectively.

Parameters

$items : array<string|int, mixed>: the items to be cached, as key-value pairs.
$duration : int|null = null: default duration in seconds before the cache will expire. If not set, default [[defaultDuration]] value is used.
$dependency : Dependency|null = null: dependency of the cached items. If the dependency changes, the corresponding values in the cache will be invalidated when it is fetched via [[get()]]. This parameter is ignored if [[serializer]] is false.

Return values

array<string|int, mixed> —

array of failed keys

off()

Detaches an existing event handler from this component.


    public
                    off(string $name[, callable|null $handler = null ]) : bool

This method is the opposite of [[on()]].

Note: in case wildcard pattern is passed for event name, only the handlers registered with this wildcard will be removed, while handlers registered with plain names matching this wildcard will remain.

Parameters

$name : string: event name
$handler : callable|null = null: the event handler to be removed. If it is null, all handlers attached to the named event will be removed.

Return values

bool —

if a handler is found and detached

offsetExists()

Returns whether there is a cache entry with a specified key.


    public
                    offsetExists(string $key) : bool

This method is required by the interface [[\ArrayAccess]].

Parameters

$key : string: a key identifying the cached value

#[ReturnTypeWillChange]

Return values

bool

offsetGet()

Retrieves the value from cache with a specified key.


    public
                    offsetGet(string $key) : mixed

This method is required by the interface [[\ArrayAccess]].

Parameters

$key : string: a key identifying the cached value

#[ReturnTypeWillChange]

Return values

mixed —

the value stored in cache, false if the value is not in the cache or expired.

offsetSet()

Stores the value identified by a key into cache.


    public
                    offsetSet(string $key, mixed $value) : mixed

If the cache already contains such a key, the existing value will be replaced with the new ones. To add expiration and dependencies, use the [[set()]] method. This method is required by the interface [[\ArrayAccess]].

Parameters

$key : string: the key identifying the value to be cached
$value : mixed: the value to be cached

#[ReturnTypeWillChange]

offsetUnset()

Deletes the value with the specified key from cache This method is required by the interface [[\ArrayAccess]].


    public
                    offsetUnset(string $key) : mixed

Parameters

$key : string: the key of the value to be deleted

#[ReturnTypeWillChange]

on()

Attaches an event handler to an event.


    public
                    on(string $name, callable $handler[, mixed $data = null ][, bool $append = true ]) : mixed

The event handler must be a valid PHP callback. The following are some examples:

function ($event) { ... }         // anonymous function
[$object, 'handleClick']          // $object->handleClick()
['Page', 'handleClick']           // Page::handleClick()
'handleClick'                     // global function handleClick()

The event handler must be defined with the following signature,

function ($event)

where $event is an [[Event]] object which includes parameters associated with the event.

Since 2.0.14 you can specify event name as a wildcard pattern:

$component->on('event.group.*', function ($event) {
    Yii::trace($event->name . ' is triggered.');
});

Parameters

$name : string: the event name
$handler : callable: the event handler
$data : mixed = null: the data to be passed to the event handler when the event is triggered. When the event handler is invoked, this data can be accessed via [[Event::data]].
$append : bool = true: whether to append new event handler to the end of the existing handler list. If false, the new handler will be inserted at the beginning of the existing handler list.

set()

Stores a value identified by a key into cache.


    public
                    set(mixed $key, mixed $value[, int|null $duration = null ][, Dependency|null $dependency = null ]) : bool

If the cache already contains such a key, the existing value and expiration time will be replaced with the new ones, respectively.

Parameters

$key : mixed: a key identifying the value to be cached. This can be a simple string or a complex data structure consisting of factors representing the key.
$value : mixed: the value to be cached
$duration : int|null = null: default duration in seconds before the cache will expire. If not set, default [[defaultDuration]] value is used.
$dependency : Dependency|null = null: dependency of the cached item. If the dependency changes, the corresponding value in the cache will be invalidated when it is fetched via [[get()]]. This parameter is ignored if [[serializer]] is false.

Return values

bool —

whether the value is successfully stored into cache

trigger()

Triggers an event.


    public
                    trigger(string $name[, Event|null $event = null ]) : mixed

This method represents the happening of an event. It invokes all attached handlers for the event including class-level handlers.

Parameters

$name : string: the event name
$event : Event|null = null: the event instance. If not set, a default [[Event]] object will be created.

addValue()

Stores a value identified by a key into cache if the cache does not contain this key.


    protected
    abstract                addValue(string $key, mixed $value, int $duration) : bool

This method should be implemented by child classes to store the data in specific cache storage.

Parameters

$key : string: the key identifying the value to be cached
$value : mixed: the value to be cached. Most often it's a string. If you have disabled [[serializer]], it could be something else.
$duration : int: the number of seconds in which the cached value will expire. 0 means never expire.

Return values

bool —

true if the value is successfully stored into cache, false otherwise

addValues()

Adds multiple key-value pairs to cache.


    protected
                    addValues(array<string|int, mixed> $data, int $duration) : array<string|int, mixed>

The default implementation calls [[addValue()]] multiple times add values one by one. If the underlying cache storage supports multi-add, this method should be overridden to exploit that feature.

Parameters

$data : array<string|int, mixed>: array where key corresponds to cache key while value is the value stored.
$duration : int: the number of seconds in which the cached values will expire. 0 means never expire.

Return values

array<string|int, mixed> —

array of failed keys

deleteValue()

Deletes a value with the specified key from cache This method should be implemented by child classes to delete the data from actual cache storage.


    protected
    abstract                deleteValue(string $key) : bool

Parameters

$key : string: the key of the value to be deleted

Return values

bool —

if no error happens during deletion

flushValues()

Deletes all values from cache.


    protected
    abstract                flushValues() : bool

Child classes may implement this method to realize the flush operation.

Return values

bool —

whether the flush operation was successful.

getValue()

Retrieves a value from cache with a specified key.


    protected
    abstract                getValue(string $key) : mixed|false

This method should be implemented by child classes to retrieve the data from specific cache storage.

Parameters

$key : string: a unique key identifying the cached value

Return values

mixed|false —

the value stored in cache, false if the value is not in the cache or expired. Most often value is a string. If you have disabled [[serializer]], it could be something else.

getValues()

Retrieves multiple values from cache with the specified keys.


    protected
                    getValues(array<string|int, mixed> $keys) : array<string|int, mixed>

The default implementation calls [[getValue()]] multiple times to retrieve the cached values one by one. If the underlying cache storage supports multiget, this method should be overridden to exploit that feature.

Parameters

$keys : array<string|int, mixed>: a list of keys identifying the cached values

Return values

array<string|int, mixed> —

a list of cached values indexed by the keys

setValue()

Stores a value identified by a key in cache.


    protected
    abstract                setValue(string $key, mixed $value, int $duration) : bool

This method should be implemented by child classes to store the data in specific cache storage.

Parameters

$key : string: the key identifying the value to be cached
$value : mixed: the value to be cached. Most often it's a string. If you have disabled [[serializer]], it could be something else.
$duration : int: the number of seconds in which the cached value will expire. 0 means never expire.

Return values

bool —

true if the value is successfully stored into cache, false otherwise

setValues()

Stores multiple key-value pairs in cache.


    protected
                    setValues(array<string|int, mixed> $data, int $duration) : array<string|int, mixed>

The default implementation calls [[setValue()]] multiple times store values one by one. If the underlying cache storage supports multi-set, this method should be overridden to exploit that feature.

Parameters

$data : array<string|int, mixed>: array where key corresponds to cache key while value is the value stored
$duration : int: the number of seconds in which the cached values will expire. 0 means never expire.

Return values

array<string|int, mixed> —

array of failed keys

attachBehaviorInternal()

Attaches a behavior to this component.


    private
                    attachBehaviorInternal(string|int $name, string|array<string|int, mixed>|Behavior $behavior) : Behavior

Parameters

$name : string|int: the name of the behavior. If this is an integer, it means the behavior is an anonymous one. Otherwise, the behavior is a named one and any existing behavior with the same name will be detached first.
$behavior : string|array<string|int, mixed>|Behavior: the behavior to be attached

Return values

Behavior —

the attached behavior.

prepareCacheData()

Prepares data for caching by serializing values and evaluating dependencies.


    private
                    prepareCacheData(array<string|int, mixed> $items, mixed $dependency) : array<string|int, mixed>

Parameters

$items : array<string|int, mixed>: The items to be cached.
$dependency : mixed: The dependency to be evaluated.

Return values

array<string|int, mixed> —

The prepared data for caching.

Cache extends Component in package Application implements CacheInterface

Tags

Table of Contents

Interfaces

Properties

Methods

Properties

$behaviors read-only

$defaultDuration

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$keyPrefix

$serializer

$_behaviors

$_events

$_eventWildcards

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$_igbinaryAvailable

Methods

__call()

Parameters

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Return values

__clone()

__construct()

Parameters

__get()

Parameters

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__isset()

Parameters

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Return values

__set()

Parameters

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__unset()

Parameters

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add()

Parameters

Return values

attachBehavior()

Parameters

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Return values

attachBehaviors()

Parameters

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behaviors()

Return values

buildKey()

Parameters

Return values

canGetProperty()

Parameters

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Return values

canSetProperty()

Parameters

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Return values

className()

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Return values

delete()

Parameters

Return values

detachBehavior()

Parameters

Return values

detachBehaviors()

ensureBehaviors()

Cache extends Component
in package

Application

implements CacheInterface