# Class yii\redis\Mutex

Inheritance | yii\redis\Mutex » yii\mutex\Mutex » yii\base\Component » yii\base\BaseObject
Implements | yii\base\Configurable
Uses Traits | yii\mutex\RetryAcquireTrait
Available since version | 2.0.6
Source Code | https://github.com/yiisoft/yii2-redis/blob/master/Mutex.php

Redis Mutex implements a mutex component using redis as the storage medium.

Redis Mutex requires redis version 2.6.12 or higher to work properly.

It needs to be configured with a redis yii\redis\Connection that is also configured as an application component. By default it will use the `redis` application component.

To use redis Mutex as the application component, configure the application as follows:

    [
        'components' => [
            'mutex' => [
                'class' => 'yii\redis\Mutex',
                'redis' => [
                    'hostname' => 'localhost',
                    'port' => 6379,
                    'database' => 0,
                ]
            ],
        ],
    ]

Or if you have configured the redis yii\redis\Connection as an application component, the following is sufficient:

    [
        'components' => [
            'mutex' => [
                'class' => 'yii\redis\Mutex',
                // 'redis' => 'redis' // id of the connection application component
            ],
        ],
    ]

See also:

- yii\mutex\Mutex
- https://redis.io/topics/distlock

## Public Properties

Hide inherited properties

Property | Type | Description | Defined By
--- | --- | --- | ---
$autoRelease | boolean | Whether all locks acquired in this process (i.e. local locks) must be released automatically before finishing script execution. | yii\mutex\Mutex
$behaviors | yii\base\Behavior[] | List of behaviors attached to this component. | yii\base\Component
$expire | integer | The number of seconds in which the lock will be auto released. | yii\redis\Mutex
$keyPrefix | string | A string prefixed to every cache key so that it is unique. | yii\redis\Mutex
$redis | yii\redis\Connection|string|array | The Redis yii\redis\Connection object or the application component ID of the Redis yii\redis\Connection. | yii\redis\Mutex
$retryDelay | integer | Number of milliseconds between each try in acquire() until specified timeout times out. | yii\mutex\RetryAcquireTrait

## Public Methods

Hide inherited 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
acquire() | Acquires a lock by name. | yii\mutex\Mutex
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
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
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
getBehavior() | Returns the named behavior object. | yii\base\Component
getBehaviors() | Returns all behaviors attached to this component. | yii\base\Component
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 the redis Mutex component. | yii\redis\Mutex
isAcquired() | Checks if a lock is acquired by the current process. | yii\mutex\Mutex
off() | Detaches an existing event handler from this component. | yii\base\Component
on() | Attaches an event handler to an event. | yii\base\Component
release() | Releases acquired lock. This method will return false in case the lock was not found. | yii\mutex\Mutex
trigger() | Triggers an event. | yii\base\Component

## Protected Methods

Hide inherited methods

Method | Description | Defined By
--- | --- | ---
acquireLock() | Acquires a lock by name. | yii\redis\Mutex
calculateKey() | Generates a unique key used for storing the mutex in Redis. | yii\redis\Mutex
releaseLock() | Releases acquired lock. This method will return `false` in case the lock was not found or Redis command failed. | yii\redis\Mutex

## Property Details

Hide inherited properties

$expire public property

The number of seconds in which the lock will be auto released.

public integer $expire = 30
$keyPrefix public property

A string prefixed to every cache key so that it is unique. If not set, it will use a prefix generated from yii\base\Application::$id. You may set this property to be an empty string if you don't want to use key prefix. It is recommended that you explicitly set this property to some static value if the cached data needs to be shared among multiple applications.

public string $keyPrefix = null
$redis public property

The Redis yii\redis\Connection object or the application component ID of the Redis yii\redis\Connection. This can also be an array that is used to create a redis yii\redis\Connection instance in case you do not want do configure redis connection as an application component. After the Mutex object is created, if you want to change this property, you should only assign it with a Redis yii\redis\Connection object.

public yii\redis\Connection|string|array $redis = 'redis'

## Method Details

Hide inherited methods

__call() public method

Defined in: yii\base\Component::__call()

Calls the named method which is not a class method.

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.

public mixed __call ( $name, $params )
$name | string | The method name
$params | array | Method parameters
return | mixed | The method return value
throws | yii\base\UnknownMethodException | when calling unknown method

Source code

                    public function __call($name, $params)
    {
        $this->ensureBehaviors();
        foreach ($this->_behaviors as $object) {
            if ($object->hasMethod($name)) {
                return call_user_func_array([$object, $name], $params);
            }
        }
        throw new UnknownMethodException('Calling unknown method: ' . get_class($this) . "::$name()");
    }

__clone() public method

Defined in: yii\base\Component::__clone()

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

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

public void __clone ( )

Source code

                    public function __clone()
    {
        $this->_events = [];
        $this->_eventWildcards = [];
        $this->_behaviors = null;
    }

__construct() public method

Defined in: yii\base\BaseObject::__construct()

Constructor.

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.

public void __construct ( $config = [] )
$config | array | Name-value pairs that will be used to initialize the object properties

Source code

                    public function __construct($config = [])
    {
        if (!empty($config)) {
            Yii::configure($this, $config);
        }
        $this->init();
    }

__get() public method

Defined in: yii\base\Component::__get()

Returns the value of a component property.

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;`.

See also __set().

public mixed __get ( $name )
$name | string | The property name
return | mixed | The property value or the value of a behavior's property
throws | yii\base\UnknownPropertyException | if the property is not defined
throws | yii\base\InvalidCallException | if the property is write-only.

Source code

                    public function __get($name)
    {
        $getter = 'get' . $name;
        if (method_exists($this, $getter)) {
            // read property, e.g. getName()
            return $this->$getter();
        }
        // behavior property
        $this->ensureBehaviors();
        foreach ($this->_behaviors as $behavior) {
            if ($behavior->canGetProperty($name)) {
                return $behavior->$name;
            }
        }
        if (method_exists($this, 'set' . $name)) {
            throw new InvalidCallException('Getting write-only property: ' . get_class($this) . '::' . $name);
        }
        throw new UnknownPropertyException('Getting unknown property: ' . get_class($this) . '::' . $name);
    }

__isset() public method

Defined in: yii\base\Component::__isset()

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

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)`.

See also https://www.php.net/manual/en/function.isset.php.

public boolean __isset ( $name )
$name | string | The property name or the event name
return | boolean | Whether the named property is set

Source code

                    public function __isset($name)
    {
        $getter = 'get' . $name;
        if (method_exists($this, $getter)) {
            return $this->$getter() !== null;
        }
        // behavior property
        $this->ensureBehaviors();
        foreach ($this->_behaviors as $behavior) {
            if ($behavior->canGetProperty($name)) {
                return $behavior->$name !== null;
            }
        }
        return false;
    }

__set() public method

Defined in: yii\base\Component::__set()

Sets the value of a component property.

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;`.

See also __get().

public void __set ( $name, $value )
$name | string | The property name or the event name
$value | mixed | The property value
throws | yii\base\UnknownPropertyException | if the property is not defined
throws | yii\base\InvalidCallException | if the property is read-only.

Source code

                    public function __set($name, $value)
    {
        $setter = 'set' . $name;
        if (method_exists($this, $setter)) {
            // set property
            $this->$setter($value);
            return;
        } elseif (strncmp($name, 'on ', 3) === 0) {
            // on event: attach event handler
            $this->on(trim(substr($name, 3)), $value);
            return;
        } elseif (strncmp($name, 'as ', 3) === 0) {
            // as behavior: attach behavior
            $name = trim(substr($name, 3));
            $this->attachBehavior($name, $value instanceof Behavior ? $value : Yii::createObject($value));
            return;
        }
        // behavior property
        $this->ensureBehaviors();
        foreach ($this->_behaviors as $behavior) {
            if ($behavior->canSetProperty($name)) {
                $behavior->$name = $value;
                return;
            }
        }
        if (method_exists($this, 'get' . $name)) {
            throw new InvalidCallException('Setting read-only property: ' . get_class($this) . '::' . $name);
        }
        throw new UnknownPropertyException('Setting unknown property: ' . get_class($this) . '::' . $name);
    }

__unset() public method

Defined in: yii\base\Component::__unset()

Sets a component property to be null.

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)`.

See also https://www.php.net/manual/en/function.unset.php.

public void __unset ( $name )
$name | string | The property name
throws | yii\base\InvalidCallException | if the property is read only.

Source code

                    public function __unset($name)
    {
        $setter = 'set' . $name;
        if (method_exists($this, $setter)) {
            $this->$setter(null);
            return;
        }
        // behavior property
        $this->ensureBehaviors();
        foreach ($this->_behaviors as $behavior) {
            if ($behavior->canSetProperty($name)) {
                $behavior->$name = null;
                return;
            }
        }
        throw new InvalidCallException('Unsetting an unknown or read-only property: ' . get_class($this) . '::' . $name);
    }

acquire() public method

Defined in: yii\mutex\Mutex::acquire()

Acquires a lock by name.

public boolean acquire ( $name, $timeout = 0 )
$name | string | Of the lock to be acquired. Must be unique.
$timeout | integer | 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 | boolean | Lock acquiring result.

Source code

                    public function acquire($name, $timeout = 0)
    {
        if (!in_array($name, $this->_locks, true) && $this->acquireLock($name, $timeout)) {
            $this->_locks[] = $name;
            return true;
        }
        return false;
    }

acquireLock() protected method

Acquires a lock by name.

protected boolean acquireLock ( $name, $timeout = 0 )
$name | string | Of the lock to be acquired. Must be unique.
$timeout | integer | Time (in seconds) to wait for lock to be released. Defaults to `0` meaning that method will return false immediately in case lock was already acquired.
return | boolean | Lock acquiring result.

Source code

                    protected function acquireLock($name, $timeout = 0)
    {
        $key = $this->calculateKey($name);
        $value = Yii::$app->security->generateRandomString(20);
        $result = $this->retryAcquire($timeout, function () use ($key, $value) {
            return $this->redis->executeCommand('SET', [$key, $value, 'NX', 'PX', (int) ($this->expire * 1000)]);
        });
        if ($result) {
            $this->_lockValues[$name] = $value;
        }
        return $result;
    }

attachBehavior() public method

Defined in: yii\base\Component::attachBehavior()

Attaches a behavior to this component.

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 yii\base\Behavior::attach() method.

See also detachBehavior().

public yii\base\Behavior attachBehavior ( $name, $behavior )
$name | string | The name of the behavior.

$behavior

string|array|yii\base\Behavior

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

- a yii\base\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 | yii\base\Behavior | The behavior object

Source code

                    public function attachBehavior($name, $behavior)
    {
        $this->ensureBehaviors();
        return $this->attachBehaviorInternal($name, $behavior);
    }

attachBehaviors() public method

Defined in: yii\base\Component::attachBehaviors()

Attaches a list of behaviors to the component.

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

See also attachBehavior().

public void attachBehaviors ( $behaviors )
$behaviors | array | List of behaviors to be attached to the component

Source code

                    public function attachBehaviors($behaviors)
    {
        $this->ensureBehaviors();
        foreach ($behaviors as $name => $behavior) {
            $this->attachBehaviorInternal($name, $behavior);
        }
    }

behaviors() public method

Defined in: yii\base\Component::behaviors()

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

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 yii\base\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).

public array behaviors ( )
return | array | The behavior configurations.

Source code

                    public function behaviors()
    {
        return [];
    }

calculateKey() protected method

Generates a unique key used for storing the mutex in Redis.

protected string calculateKey ( $name )
$name | string | Mutex name.
return | string | A safe cache key associated with the mutex name.

Source code

                    protected function calculateKey($name)
    {
        return $this->keyPrefix . md5(json_encode([__CLASS__, $name]));
    }

canGetProperty() public method

Defined in: yii\base\Component::canGetProperty()

Returns a value indicating whether a property can be read.

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).

See also canSetProperty().

public boolean canGetProperty ( $name, $checkVars = true, $checkBehaviors = true )
$name | string | The property name
$checkVars | boolean | Whether to treat member variables as properties
$checkBehaviors | boolean | Whether to treat behaviors' properties as properties of this component
return | boolean | Whether the property can be read

Source code

                    public function canGetProperty($name, $checkVars = true, $checkBehaviors = true)
    {
        if (method_exists($this, 'get' . $name) || $checkVars && property_exists($this, $name)) {
            return true;
        } elseif ($checkBehaviors) {
            $this->ensureBehaviors();
            foreach ($this->_behaviors as $behavior) {
                if ($behavior->canGetProperty($name, $checkVars)) {
                    return true;
                }
            }
        }
        return false;
    }

canSetProperty() public method

Defined in: yii\base\Component::canSetProperty()

Returns a value indicating whether a property can be set.

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).

See also canGetProperty().

public boolean canSetProperty ( $name, $checkVars = true, $checkBehaviors = true )
$name | string | The property name
$checkVars | boolean | Whether to treat member variables as properties
$checkBehaviors | boolean | Whether to treat behaviors' properties as properties of this component
return | boolean | Whether the property can be written

Source code

                    public function canSetProperty($name, $checkVars = true, $checkBehaviors = true)
    {
        if (method_exists($this, 'set' . $name) || $checkVars && property_exists($this, $name)) {
            return true;
        } elseif ($checkBehaviors) {
            $this->ensureBehaviors();
            foreach ($this->_behaviors as $behavior) {
                if ($behavior->canSetProperty($name, $checkVars)) {
                    return true;
                }
            }
        }
        return false;
    }

className() public static method
Deprecated since 2.0.14. On PHP >=5.5, use `::class` instead.

Defined in: yii\base\BaseObject::className()

Returns the fully qualified name of this class.

public static string className ( )
return | string | The fully qualified name of this class.

Source code

                    public static function className()
    {
        return get_called_class();
    }

detachBehavior() public method

Defined in: yii\base\Component::detachBehavior()

Detaches a behavior from the component.

The behavior's yii\base\Behavior::detach() method will be invoked.

public yii\base\Behavior|null detachBehavior ( $name )
$name | string | The behavior's name.
return | yii\base\Behavior|null | The detached behavior. Null if the behavior does not exist.

Source code

                    public function detachBehavior($name)
    {
        $this->ensureBehaviors();
        if (isset($this->_behaviors[$name])) {
            $behavior = $this->_behaviors[$name];
            unset($this->_behaviors[$name]);
            $behavior->detach();
            return $behavior;
        }
        return null;
    }

detachBehaviors() public method

Defined in: yii\base\Component::detachBehaviors()

Detaches all behaviors from the component.

public void detachBehaviors ( )

Source code

                    public function detachBehaviors()
    {
        $this->ensureBehaviors();
        foreach ($this->_behaviors as $name => $behavior) {
            $this->detachBehavior($name);
        }
    }

ensureBehaviors() public method

Defined in: yii\base\Component::ensureBehaviors()

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

public void ensureBehaviors ( )

Source code

                    public function ensureBehaviors()
    {
        if ($this->_behaviors === null) {
            $this->_behaviors = [];
            foreach ($this->behaviors() as $name => $behavior) {
                $this->attachBehaviorInternal($name, $behavior);
            }
        }
    }

getBehavior() public method

Defined in: yii\base\Component::getBehavior()

Returns the named behavior object.

public yii\base\Behavior|null getBehavior ( $name )
$name | string | The behavior name
return | yii\base\Behavior|null | The behavior object, or null if the behavior does not exist

Source code

                    public function getBehavior($name)
    {
        $this->ensureBehaviors();
        return isset($this->_behaviors[$name]) ? $this->_behaviors[$name] : null;
    }

getBehaviors() public method

Defined in: yii\base\Component::getBehaviors()

Returns all behaviors attached to this component.

public yii\base\Behavior[] getBehaviors ( )
return | yii\base\Behavior[] | List of behaviors attached to this component

Source code

                    public function getBehaviors()
    {
        $this->ensureBehaviors();
        return $this->_behaviors;
    }

hasEventHandlers() public method

Defined in: yii\base\Component::hasEventHandlers()

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

public boolean hasEventHandlers ( $name )
$name | string | The event name
return | boolean | Whether there is any handler attached to the event.

Source code

                    public function hasEventHandlers($name)
    {
        $this->ensureBehaviors();
        if (!empty($this->_events[$name])) {
            return true;
        }
        foreach ($this->_eventWildcards as $wildcard => $handlers) {
            if (!empty($handlers) && StringHelper::matchWildcard($wildcard, $name)) {
                return true;
            }
        }
        return Event::hasHandlers($this, $name);
    }

hasMethod() public method

Defined in: yii\base\Component::hasMethod()

Returns a value indicating whether a method is defined.

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).

public boolean hasMethod ( $name, $checkBehaviors = true )
$name | string | The property name
$checkBehaviors | boolean | Whether to treat behaviors' methods as methods of this component
return | boolean | Whether the method is defined

Source code

                    public function hasMethod($name, $checkBehaviors = true)
    {
        if (method_exists($this, $name)) {
            return true;
        } elseif ($checkBehaviors) {
            $this->ensureBehaviors();
            foreach ($this->_behaviors as $behavior) {
                if ($behavior->hasMethod($name)) {
                    return true;
                }
            }
        }
        return false;
    }

hasProperty() public method

Defined in: yii\base\Component::hasProperty()

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

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).

See also:

- canGetProperty()
- canSetProperty()

public boolean hasProperty ( $name, $checkVars = true, $checkBehaviors = true )
$name | string | The property name
$checkVars | boolean | Whether to treat member variables as properties
$checkBehaviors | boolean | Whether to treat behaviors' properties as properties of this component
return | boolean | Whether the property is defined

Source code

                    public function hasProperty($name, $checkVars = true, $checkBehaviors = true)
    {
        return $this->canGetProperty($name, $checkVars, $checkBehaviors) || $this->canSetProperty($name, false, $checkBehaviors);
    }

init() public method

Initializes the redis Mutex component.

This method will initialize the $redis property to make sure it refers to a valid redis connection.

public void init ( )
throws | yii\base\InvalidConfigException | if $redis is invalid.

Source code

                    public function init()
    {
        parent::init();
        $this->redis = Instance::ensure($this->redis, Connection::className());
        if ($this->keyPrefix === null) {
            $this->keyPrefix = substr(md5(Yii::$app->id), 0, 5);
        }
    }

isAcquired() public method (available since version 2.0.36)

Defined in: yii\mutex\Mutex::isAcquired()

Checks if a lock is acquired by the current process.

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

public boolean isAcquired ( $name )
$name | string | Of the lock to check.
return | boolean | Returns true if currently acquired.

Source code

                    public function isAcquired($name)
    {
        return in_array($name, $this->_locks, true);
    }

off() public method

Defined in: yii\base\Component::off()

Detaches an existing event handler from this component.

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.

See also on().

public boolean off ( $name, $handler = null )
$name | string | Event name
$handler | callable|null | The event handler to be removed. If it is null, all handlers attached to the named event will be removed.
return | boolean | If a handler is found and detached

Source code

                    public function off($name, $handler = null)
    {
        $this->ensureBehaviors();
        if (empty($this->_events[$name]) && empty($this->_eventWildcards[$name])) {
            return false;
        }
        if ($handler === null) {
            unset($this->_events[$name], $this->_eventWildcards[$name]);
            return true;
        }
        $removed = false;
        // plain event names
        if (isset($this->_events[$name])) {
            foreach ($this->_events[$name] as $i => $event) {
                if ($event[0] === $handler) {
                    unset($this->_events[$name][$i]);
                    $removed = true;
                }
            }
            if ($removed) {
                $this->_events[$name] = array_values($this->_events[$name]);
                return true;
            }
        }
        // wildcard event names
        if (isset($this->_eventWildcards[$name])) {
            foreach ($this->_eventWildcards[$name] as $i => $event) {
                if ($event[0] === $handler) {
                    unset($this->_eventWildcards[$name][$i]);
                    $removed = true;
                }
            }
            if ($removed) {
                $this->_eventWildcards[$name] = array_values($this->_eventWildcards[$name]);
                // remove empty wildcards to save future redundant regex checks:
                if (empty($this->_eventWildcards[$name])) {
                    unset($this->_eventWildcards[$name]);
                }
            }
        }
        return $removed;
    }

on() public method

Defined in: yii\base\Component::on()

Attaches an event handler to an event.

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 yii\base\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.');
    });

See also off().

public void on ( $name, $handler, $data = null, $append = true )
$name | string | The event name
$handler | callable | The event handler
$data | mixed | The data to be passed to the event handler when the event is triggered. When the event handler is invoked, this data can be accessed via yii\base\Event::$data.
$append | boolean | 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.

Source code

                    public function on($name, $handler, $data = null, $append = true)
    {
        $this->ensureBehaviors();
        if (strpos($name, '*') !== false) {
            if ($append || empty($this->_eventWildcards[$name])) {
                $this->_eventWildcards[$name][] = [$handler, $data];
            } else {
                array_unshift($this->_eventWildcards[$name], [$handler, $data]);
            }
            return;
        }
        if ($append || empty($this->_events[$name])) {
            $this->_events[$name][] = [$handler, $data];
        } else {
            array_unshift($this->_events[$name], [$handler, $data]);
        }
    }

release() public method

Defined in: yii\mutex\Mutex::release()

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

public boolean release ( $name )
$name | string | Of the lock to be released. This lock must already exist.
return | boolean | Lock release result: false in case named lock was not found..

Source code

                    public function release($name)
    {
        if ($this->releaseLock($name)) {
            $index = array_search($name, $this->_locks);
            if ($index !== false) {
                unset($this->_locks[$index]);
            }
            return true;
        }
        return false;
    }

releaseLock() protected method

Releases acquired lock. This method will return `false` in case the lock was not found or Redis command failed.

protected boolean releaseLock ( $name )
$name | string | Of the lock to be released. This lock must already exist.
return | boolean | Lock release result: `false` in case named lock was not found or Redis command failed.

Source code

                    protected function releaseLock($name)
    {
        static $releaseLuaScript = <<<LUA
    edis.call("GET",KEYS[1])==ARGV[1] then
    return redis.call("DEL",KEYS[1])

    return 0

        if (
            !isset($this->_lockValues[$name])
            || !$this->redis->executeCommand('EVAL', [
                $releaseLuaScript,
                1,
                $this->calculateKey($name),
                $this->_lockValues[$name],
            ])
        ) {
            return false;
        }
        unset($this->_lockValues[$name]);
        return true;
    }

trigger() public method

Defined in: yii\base\Component::trigger()

Triggers an event.

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

public void trigger ( $name, yii\base\Event $event = null )
$name | string | The event name
$event | yii\base\Event|null | The event instance. If not set, a default yii\base\Event object will be created.

Source code

                    public function trigger($name, Event $event = null)
    {
        $this->ensureBehaviors();
        $eventHandlers = [];
        foreach ($this->_eventWildcards as $wildcard => $handlers) {
            if (StringHelper::matchWildcard($wildcard, $name)) {
                $eventHandlers[] = $handlers;
            }
        }
        if (!empty($this->_events[$name])) {
            $eventHandlers[] = $this->_events[$name];
        }
        if (!empty($eventHandlers)) {
            $eventHandlers = call_user_func_array('array_merge', $eventHandlers);
            if ($event === null) {
                $event = new Event();
            }
            if ($event->sender === null) {
                $event->sender = $this;
            }
            $event->handled = false;
            $event->name = $name;
            foreach ($eventHandlers as $handler) {
                $event->data = $handler[1];
                call_user_func($handler[0], $event);
                // stop further handling if the event is handled
                if ($event->handled) {
                    return;
                }
            }
        }
        // invoke class-level attached handlers
        Event::trigger($this, $name, $event);
    }