SluggableBehavior

API reference › yii › behaviors › SluggableBehavior

class	`yii\behaviors\SluggableBehavior`
Extends	`AttributeBehavior` » `yii\base\Behavior` » `yii\base\BaseObject`
Implements	`yii\base\Configurable`
Since	2.0
Source	`framework/behaviors/SluggableBehavior.php`

SluggableBehavior automatically fills the specified attribute with a value that can be used a slug in a URL.

Note: This behavior relies on php-intl extension for transliteration. If it is not installed it falls back to replacements defined in Inflector::$transliteration.

To use SluggableBehavior, insert the following code to your ActiveRecord class:

use yii\behaviors\SluggableBehavior;

public function behaviors()
{
    return [
        [
            'class' => SluggableBehavior::class,
            'attribute' => 'title',
            // 'slugAttribute' => 'slug',
        ],
    ];
}

By default, SluggableBehavior will fill the slug attribute with a value that can be used a slug in a URL when the associated AR object is being validated.

Because attribute values will be set automatically by this behavior, they are usually not user input and should therefore not be validated, i.e. the slug attribute should not appear in the rules() method of the model.

If your attribute name is different, you may configure the $slugAttribute property like the following:

public function behaviors()
{
    return [
        [
            'class' => SluggableBehavior::class,
            'slugAttribute' => 'alias',
        ],
    ];
}

Properties

Property	Type	Description	Defined by
`$attribute`	`string\|array\|null`	The attribute or list of attributes whose value will be converted into a slug or `null` meaning that the `$value` property will be used to generate a slug. Default: `null`.	`SluggableBehavior`
`$attributes`	`array`	List of attributes that are to be automatically filled with the value specified via `$value`. Default: `[]`.	`AttributeBehavior`
`$ensureUnique`	`bool`	Whether to ensure generated slug value to be unique among owner class records. Default: `false`.	`SluggableBehavior`
`$immutable`	`bool`	Whether to generate a new slug if it has already been generated before. Default: `false`. Available since 2.0.2.	`SluggableBehavior`
`$owner`	`yii\base\T\|null`	The owner of this behavior Default: `null`.	`yii\base\Behavior`
`$preserveNonEmptyValues`	`bool`	Whether to preserve non-empty attribute values. Default: `false`. Available since 2.0.13.	`AttributeBehavior`
`$skipOnEmpty`	`bool`	Whether to skip slug generation if `$attribute` is null or an empty string. Default: `false`. Available since 2.0.13.	`SluggableBehavior`
`$skipUpdateOnClean`	`bool`	Whether to skip this behavior when the `$owner` has not been modified Default: `true`. Available since 2.0.8.	`AttributeBehavior`
`$slugAttribute`	`string`	The attribute that will receive the slug value Default: `'slug'`.	`SluggableBehavior`
`$uniqueSlugGenerator`	`callable\|null`	Slug unique value generator. Default: `null`.	`SluggableBehavior`
`$uniqueValidator`	`array`	Configuration for slug uniqueness validator. Default: `[]`.	`SluggableBehavior`
`$value`	`callable\|string\|null`	The value that will be used as a slug. Default: `null`.	`SluggableBehavior`

Methods

Method	Description	Defined by
`__construct()`	Constructor.	`yii\base\BaseObject`
`__call()`	Calls the named method which is not a class method.	`yii\base\BaseObject`
`__get()`	Returns the value of an object property.	`yii\base\BaseObject`
`__isset()`	Checks if a property is set, i.e. defined and not null.	`yii\base\BaseObject`
`__set()`	Sets value of an object property.	`yii\base\BaseObject`
`__unset()`	Sets an object property to null.	`yii\base\BaseObject`
`attach()`	Attaches the behavior object to the component.	`yii\base\Behavior`
`canGetProperty()`	Returns a value indicating whether a property can be read.	`yii\base\BaseObject`
`canSetProperty()`	Returns a value indicating whether a property can be set.	`yii\base\BaseObject`
`className()` static	Returns the fully qualified name of this class.	`yii\base\BaseObject`
`detach()`	Detaches the behavior object from the component.	`yii\base\Behavior`
`evaluateAttributes()`	Evaluates the attribute value and assigns it to the current attributes.	`AttributeBehavior`
`events()`	Declares event handlers for the `$owner`’s events.	`AttributeBehavior`
`hasMethod()`	Returns a value indicating whether a method is defined.	`yii\base\BaseObject`
`hasProperty()`	Returns a value indicating whether a property is defined.	`yii\base\BaseObject`
`init()`	Initializes the object.	`SluggableBehavior`
`generateSlug()` protected	This method is called by `getValue()` to generate the slug.	`SluggableBehavior`
`generateUniqueSlug()` protected	Generates slug using configured callback or increment of iteration.	`SluggableBehavior`
`getValue()` protected	Returns the value for the current attributes.	`SluggableBehavior`
`isEmpty()` protected	Checks if $slugPart is empty string or null.	`SluggableBehavior`
`isNewSlugNeeded()` protected	Checks whether the new slug generation is needed This method is called by `getValue()` to check whether the new slug generation is needed.	`SluggableBehavior`
`makeUnique()` protected	This method is called by `getValue()` when `$ensureUnique` is true to generate the unique slug.	`SluggableBehavior`
`validateSlug()` protected	Checks if given slug value is unique.	`SluggableBehavior`

Property details

$ensureUnique

public bool $ensureUnique = false

Whether to ensure generated slug value to be unique among owner class records.

If enabled behavior will validate slug uniqueness automatically. If validation fails it will attempt generating unique slug value from based one until success.

$immutable

public bool $immutable = false

Whether to generate a new slug if it has already been generated before.

If true, the behavior will not generate a new slug even if $attribute is changed.

Since

2.0.2

$skipOnEmpty

public bool $skipOnEmpty = false

Whether to skip slug generation if $attribute is null or an empty string.

If true, the behaviour will not generate a new slug if $attribute is null or an empty string.

Since

2.0.13

$uniqueSlugGenerator

public callable|null $uniqueSlugGenerator = null

Slug unique value generator.

It is used in case $ensureUnique enabled and generated slug is not unique. This should be a PHP callable with following signature:

function ($baseSlug, $iteration, $model)
{
    // return uniqueSlug
}

If not set unique slug will be generated adding incrementing suffix to the base slug.

$uniqueValidator

public array $uniqueValidator = []

Configuration for slug uniqueness validator.

Parameter ‘class’ may be omitted - by default UniqueValidator will be used.

$value

public callable|string|null $value = null

The value that will be used as a slug.

This can be an anonymous function or an arbitrary value or null. If the former, the return value of the function will be used as a slug. If null then the $attribute property will be used to generate a slug. The signature of the function should be as follows,

function ($event)
{
    // return slug
}

Method details

init()

public function init(): mixed

Initializes the object.

This method is invoked at the end of the constructor after the object is initialized with the given configuration.

Returns

mixed

generateSlug()

protected function generateSlug(array $slugParts): string

This method is called by getValue() to generate the slug.

You may override it to customize slug generation. The default implementation calls Inflector::slug() on the input strings concatenated by dashes (-).

Parameters

Parameter	Type	Description
`$slugParts`	`array`	An array of strings that should be concatenated and converted to generate the slug value.

Returns

string: The conversion result.

generateUniqueSlug()

protected function generateUniqueSlug(string $baseSlug, int $iteration): string

Generates slug using configured callback or increment of iteration.

Parameters

Parameter	Type	Description
`$baseSlug`	`string`	Base slug value
`$iteration`	`int`	Iteration number

Returns

string: New slug value

Throws

yii\base\InvalidConfigException

getValue()

protected function getValue(mixed $event): mixed

Returns the value for the current attributes.

This method is called by evaluateAttributes(). Its return value will be assigned to the attributes corresponding to the triggering event.

Parameters

Parameter	Type	Description
`$event`	`mixed`	The event that triggers the current attribute updating.

Returns

mixed: The attribute value

isEmpty()

protected function isEmpty(string $slugPart): bool

Checks if $slugPart is empty string or null.

Parameters

Parameter	Type	Description
`$slugPart`	`string`	One of attributes that is used for slug generation.

Returns

bool: Whether $slugPart empty or not.

Since

2.0.13

isNewSlugNeeded()

protected function isNewSlugNeeded(): bool

Checks whether the new slug generation is needed This method is called by getValue() to check whether the new slug generation is needed.

You may override it to customize checking.

Returns

bool

Since

2.0.7

makeUnique()

protected function makeUnique(string $slug): string

This method is called by getValue() when $ensureUnique is true to generate the unique slug.

Calls generateUniqueSlug() until generated slug is unique and returns it.

Parameters

Parameter	Type	Description
`$slug`	`string`	Basic slug value

Returns

string: Unique slug

Since

2.0.7

See also

validateSlug()

protected function validateSlug(string $slug): bool

Checks if given slug value is unique.

Parameters

Parameter	Type	Description
`$slug`	`string`	Slug value

Returns

bool: Whether slug is unique.