HumHub Documentation (unofficial)

Mutex extends Component
in package

Application

AbstractYes

The Mutex component allows mutual execution of concurrent processes in order to prevent "race conditions".

This is achieved by using a "lock" mechanism. Each possibly concurrent thread cooperates by acquiring a lock before accessing the corresponding data.

Usage example:

if ($mutex->acquire($mutexName)) {
    // business logic execution
} else {
    // execution is blocked!
}

This is a base class, which should be extended in order to implement the actual lock mechanism.

Properties

$autoRelease : bool
$behaviors : array<string|int, Behavior>
$_behaviors : array<string|int, Behavior>|null
$_events : array<string|int, mixed>
$_eventWildcards : array<string|int, mixed>
$_locks : array<string|int, string>

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.
acquire() : bool: Acquires a lock by name.
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.
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.
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.
getBehavior() : Behavior|null: Returns the named behavior object.
getBehaviors() : array<string|int, Behavior>: Returns all behaviors attached to this component.
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 Mutex component.
isAcquired() : bool: Checks if a lock is acquired by the current process.
off() : bool: Detaches an existing event handler from this component.
on() : mixed: Attaches an event handler to an event.
release() : bool: Releases acquired lock. This method will return false in case the lock was not found.
trigger() : mixed: Triggers an event.
acquireLock() : bool: This method should be extended by a concrete Mutex implementations. Acquires lock by name.
releaseLock() : bool: This method should be extended by a concrete Mutex implementations. Releases lock by given name.
attachBehaviorInternal() : Behavior: Attaches a behavior to this component.

$autoRelease


    public
        bool
    $autoRelease
     = true

whether all locks acquired in this process (i.e. local locks) must be released automatically before finishing script execution. Defaults to true. Setting this property to true means that all locks acquired in this process must be released (regardless of errors or exceptions).

$behaviors read-only


    public
        array<string|int, Behavior>
    $behaviors

List of behaviors attached to this component.

$_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)

$_locks


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

names of the locks acquired by the current PHP process.

__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

acquire()

Acquires a lock by name.


    public
                    acquire(string $name[, int $timeout = 0 ]) : bool

Parameters

$name : string: of the lock to be acquired. Must be unique.
$timeout : int = 0: time (in seconds) to wait for lock to be released. Defaults to zero meaning that method will return false immediately in case lock was already acquired.

Return values

bool —

lock acquiring result.

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.

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.

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

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

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 Mutex component.


    public
                    init() : mixed

isAcquired()

Checks if a lock is acquired by the current process.


    public
                    isAcquired(string $name) : bool

Note that it returns false if the mutex is acquired in another process.

Parameters

$name : string: of the lock to check.

Return values

bool —

Returns true if currently acquired.

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

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.

release()

Releases acquired lock. This method will return false in case the lock was not found.


    public
                    release(string $name) : bool

Parameters

$name : string: of the lock to be released. This lock must already exist.

Return values

bool —

lock release result: false in case named lock was not found..

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.

acquireLock()

This method should be extended by a concrete Mutex implementations. Acquires lock by name.


    protected
    abstract                acquireLock(string $name[, int $timeout = 0 ]) : bool

Parameters

$name : string: of the lock to be acquired.
$timeout : int = 0: time (in seconds) to wait for the lock to be released.

Return values

bool —

acquiring result.

releaseLock()

This method should be extended by a concrete Mutex implementations. Releases lock by given name.


    protected
    abstract                releaseLock(string $name) : bool

Parameters

$name : string: of the lock to be released.

Return values

bool —

release result.

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.

Mutex extends Component in package Application

Tags

Table of Contents

Properties

Methods

Properties

$autoRelease

$behaviors read-only

$_behaviors

$_events

$_eventWildcards

Tags

$_locks

Methods

__call()

Parameters

Tags

Return values

__clone()

__construct()

Parameters

__get()

Parameters

Tags

Return values

__isset()

Parameters

Tags

Return values

__set()

Parameters

Tags

__unset()

Parameters

Tags

acquire()

Parameters

Return values

attachBehavior()

Parameters

Tags

Return values

attachBehaviors()

Parameters

Tags

behaviors()

Return values

canGetProperty()

Parameters

Tags

Return values

canSetProperty()

Parameters

Tags

Return values

className()

Tags

Return values

detachBehavior()

Parameters

Return values

detachBehaviors()

ensureBehaviors()

getBehavior()

Parameters

Return values

getBehaviors()

Return values

hasEventHandlers()

Parameters

Return values

hasMethod()

Parameters

Mutex extends Component
in package

Application