framework/behaviors/SluggableBehavior.php
<?php
/**
* @link https://www.yiiframework.com/
* @copyright Copyright (c) 2008 Yii Software LLC
* @license https://www.yiiframework.com/license/
*/
namespace yii\behaviors;
use Yii;
use yii\base\InvalidConfigException;
use yii\db\BaseActiveRecord;
use yii\helpers\ArrayHelper;
use yii\helpers\Inflector;
use yii\validators\UniqueValidator;
/**
* 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 [[\yii\helpers\Inflector::$transliteration]].
*
* To use SluggableBehavior, insert the following code to your ActiveRecord class:
*
* ```php
* 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 [[\yii\base\Model::rules()|rules()]] method of the model.
*
* If your attribute name is different, you may configure the [[slugAttribute]] property like the following:
*
* ```php
* public function behaviors()
* {
* return [
* [
* 'class' => SluggableBehavior::class,
* 'slugAttribute' => 'alias',
* ],
* ];
* }
* ```
*
* @author Alexander Kochetov <creocoder@gmail.com>
* @author Paul Klimov <klimov.paul@gmail.com>
* @since 2.0
*/
class SluggableBehavior extends AttributeBehavior
{
/**
* @var string the attribute that will receive the slug value
*/
public $slugAttribute = 'slug';
/**
* @var string|array|null the attribute or list of attributes whose value will be converted into a slug
* or `null` meaning that the `$value` property will be used to generate a slug.
*/
public $attribute;
/**
* @var callable|string|null the value that will be used as a slug. This can be an anonymous function
* or an arbitrary value or null. If the former, the return value of the function will be used as a slug.
* If `null` then the `$attribute` property will be used to generate a slug.
* The signature of the function should be as follows,
*
* ```php
* function ($event)
* {
* // return slug
* }
* ```
*/
public $value;
/**
* @var bool 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
*/
public $immutable = false;
/**
* @var bool 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.
*/
public $ensureUnique = false;
/**
* @var bool 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
*/
public $skipOnEmpty = false;
/**
* @var array configuration for slug uniqueness validator. Parameter 'class' may be omitted - by default
* [[UniqueValidator]] will be used.
* @see UniqueValidator
*/
public $uniqueValidator = [];
/**
* @var callable|null slug unique value generator. It is used in case [[ensureUnique]] enabled and generated
* slug is not unique. This should be a PHP callable with following signature:
*
* ```php
* function ($baseSlug, $iteration, $model)
* {
* // return uniqueSlug
* }
* ```
*
* If not set unique slug will be generated adding incrementing suffix to the base slug.
*/
public $uniqueSlugGenerator;
/**
* {@inheritdoc}
*/
public function init()
{
parent::init();
if (empty($this->attributes)) {
$this->attributes = [BaseActiveRecord::EVENT_BEFORE_VALIDATE => $this->slugAttribute];
}
if ($this->attribute === null && $this->value === null) {
throw new InvalidConfigException('Either "attribute" or "value" property must be specified.');
}
}
/**
* {@inheritdoc}
*/
protected function getValue($event)
{
if (!$this->isNewSlugNeeded()) {
return $this->owner->{$this->slugAttribute};
}
if ($this->attribute !== null) {
$slugParts = [];
foreach ((array) $this->attribute as $attribute) {
$part = ArrayHelper::getValue($this->owner, $attribute);
if ($this->skipOnEmpty && $this->isEmpty($part)) {
return $this->owner->{$this->slugAttribute};
}
$slugParts[] = $part;
}
$slug = $this->generateSlug($slugParts);
} else {
$slug = parent::getValue($event);
}
return $this->ensureUnique ? $this->makeUnique($slug) : $slug;
}
/**
* Checks whether the new slug generation is needed
* This method is called by [[getValue]] to check whether the new slug generation is needed.
* You may override it to customize checking.
* @return bool
* @since 2.0.7
*/
protected function isNewSlugNeeded()
{
if (empty($this->owner->{$this->slugAttribute})) {
return true;
}
if ($this->immutable) {
return false;
}
if ($this->attribute === null) {
return true;
}
foreach ((array) $this->attribute as $attribute) {
if ($this->owner->isAttributeChanged($attribute)) {
return true;
}
}
return false;
}
/**
* This method is called by [[getValue]] to generate the slug.
* You may override it to customize slug generation.
* The default implementation calls [[\yii\helpers\Inflector::slug()]] on the input strings
* concatenated by dashes (`-`).
* @param array $slugParts an array of strings that should be concatenated and converted to generate the slug value.
* @return string the conversion result.
*/
protected function generateSlug($slugParts)
{
return Inflector::slug(implode('-', $slugParts));
}
/**
* 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.
* @param string $slug basic slug value
* @return string unique slug
* @see getValue
* @see generateUniqueSlug
* @since 2.0.7
*/
protected function makeUnique($slug)
{
$uniqueSlug = $slug;
$iteration = 0;
while (!$this->validateSlug($uniqueSlug)) {
$iteration++;
$uniqueSlug = $this->generateUniqueSlug($slug, $iteration);
}
return $uniqueSlug;
}
/**
* Checks if given slug value is unique.
* @param string $slug slug value
* @return bool whether slug is unique.
*/
protected function validateSlug($slug)
{
/* @var $validator UniqueValidator */
/* @var $model BaseActiveRecord */
$validator = Yii::createObject(array_merge(
[
'class' => UniqueValidator::className(),
],
$this->uniqueValidator
));
$model = clone $this->owner;
$model->clearErrors();
$model->{$this->slugAttribute} = $slug;
$validator->validateAttribute($model, $this->slugAttribute);
return !$model->hasErrors();
}
/**
* Generates slug using configured callback or increment of iteration.
* @param string $baseSlug base slug value
* @param int $iteration iteration number
* @return string new slug value
* @throws \yii\base\InvalidConfigException
*/
protected function generateUniqueSlug($baseSlug, $iteration)
{
if (is_callable($this->uniqueSlugGenerator)) {
return call_user_func($this->uniqueSlugGenerator, $baseSlug, $iteration, $this->owner);
}
return $baseSlug . '-' . ($iteration + 1);
}
/**
* Checks if $slugPart is empty string or null.
*
* @param string $slugPart One of attributes that is used for slug generation.
* @return bool whether $slugPart empty or not.
* @since 2.0.13
*/
protected function isEmpty($slugPart)
{
return $slugPart === null || $slugPart === '';
}
}