MysqlMutex

API reference › yii › mutex › MysqlMutex

class	yii\mutex\MysqlMutex
Extends	DbMutex » Mutex » yii\base\Component » yii\base\BaseObject
Implements	yii\base\Configurable
Since	2.0
Source	framework/mutex/MysqlMutex.php

MysqlMutex implements mutex “lock” mechanism via MySQL locks.

Application configuration example:

[
    'components' => [
        'db' => [
            'class' => 'yii\db\Connection',
            'dsn' => 'mysql:host=127.0.0.1;dbname=demo',
        ]
        'mutex' => [
            'class' => 'yii\mutex\MysqlMutex',
        ],
    ],
]

See also: Mutex.

Properties

Property	Type	Description	Defined by
$autoRelease	bool	Whether all locks acquired in this process (i.e. local locks) must be released automatically before finishing script execution. Default: true.	Mutex
$behaviors read-only	array<yii\base\Behavior<static>>	List of behaviors attached to this component.	yii\base\Component
$db	yii\db\Connection|array|string	The DB connection object or the application component ID of the DB connection. Default: 'db'.	DbMutex
$keyPrefix	yii\db\Expression|string|null	Prefix value. Default: null. Available since 2.0.47.	MysqlMutex

Methods

Method	Description	Defined by
__construct()	Constructor.	yii\base\BaseObject
__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
__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.	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() static	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 MySQL specific mutex component implementation.	MysqlMutex
isAcquired()	Checks if a lock is acquired by the current process.	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.	Mutex
trigger()	Triggers an event.	yii\base\Component
acquireLock() protected	Acquires lock by given name.	MysqlMutex
hashLockName() protected	Generate hash for lock name to avoid exceeding lock name length limit.	MysqlMutex
prepareName() protected	Prepare lock name	MysqlMutex
releaseLock() protected	Releases lock by given name.	MysqlMutex

Property details

$keyPrefix

public yii\db\Expression|string|null $keyPrefix = null

Prefix value.

If null (by default) then connection’s current database name is used.

Since

2.0.47

Method details

init()

public function init(): mixed

Initializes MySQL specific mutex component implementation.

Returns

mixed

Throws

• yii\base\InvalidConfigException: if $db is not MySQL connection.

acquireLock()

protected function acquireLock(string $name, int $timeout = 0): bool

Acquires lock by given name.

Parameters

Parameter	Type	Description
$name	string	Of the lock to be acquired.
$timeout	int	Time (in seconds) to wait for lock to become released.

Returns

bool: Acquiring result.

See also

• https://dev.mysql.com/doc/refman/8.0/en/miscellaneous-functions.html#function_get-lock

hashLockName()

protected function hashLockName(string $name): string

Generate hash for lock name to avoid exceeding lock name length limit.

Parameters

Parameter	Type	Description
$name	string

Returns

string

Since

2.0.16

See also

• https://github.com/yiisoft/yii2/pull/16836

prepareName()

protected function prepareName(): array

Prepare lock name

Returns

array: Expression and params

Since

2.0.48

releaseLock()

protected function releaseLock(string $name): bool

Releases lock by given name.

Parameters

Parameter	Type	Description
$name	string	Of the lock to be released.

Returns

bool: Release result.

See also

• https://dev.mysql.com/doc/refman/8.0/en/miscellaneous-functions.html#function_release-lock