| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171 | <?php/** * @link http://www.yiiframework.com/ * @copyright Copyright (c) 2008 Yii Software LLC * @license http://www.yiiframework.com/license/ */namespace yii\behaviors;use Yii;use yii\db\BaseActiveRecord;use yii\base\InvalidCallException;use yii\validators\NumberValidator;use yii\helpers\ArrayHelper;/** * OptimisticLockBehavior automatically upgrades a model's lock version using the column name * returned by [[\yii\db\BaseActiveRecord::optimisticLock()|optimisticLock()]]. * * Optimistic locking allows multiple users to access the same record for edits and avoids * potential conflicts. In case when a user attempts to save the record upon some staled data * (because another user has modified the data), a [[StaleObjectException]] exception will be thrown, * and the update or deletion is skipped. * * To use this behavior, first enable optimistic lock by following the steps listed in * [[\yii\db\BaseActiveRecord::optimisticLock()|optimisticLock()]], remove the column name * holding the lock version from the [[\yii\base\Model::rules()|rules()]] method of your * ActiveRecord class, then add the following code to it: * * ```php * use yii\behaviors\OptimisticLockBehavior; * * public function behaviors() * { *     return [ *         OptimisticLockBehavior::className(), *     ]; * } * ``` * * By default, OptimisticLockBehavior will use [[\yii\web\Request::getBodyParam()|getBodyParam()]] to parse * the submitted value or set it to 0 on any fail. That means a request not holding the version attribute * may achieve a first successful update to entity, but starting from there any further try should fail * unless the request is holding the expected version number. * * Once attached, internal use of the model class should also fail to save the record if the version number * isn't held by [[\yii\web\Request::getBodyParam()|getBodyParam()]]. It may be useful to extend your model class, * enable optimistic lock in parent class by overriding [[\yii\db\BaseActiveRecord::optimisticLock()|optimisticLock()]], * then attach the behavior to the child class so you can tie the parent model to internal use while linking the child model * holding this behavior to the controllers responsible of receiving end user inputs. * Alternatively, you can also configure the [[value]] property with a PHP callable to implement a different logic. * * OptimisticLockBehavior also provides a method named [[upgrade()]] that increases a model's * version by one, that may be useful when you need to mark an entity as stale among connected clients * and avoid any change to it until they load it again: * * ```php * $model->upgrade(); * ``` * * @author Salem Ouerdani <tunecino@gmail.com> * @since 2.0.16 * @see \yii\db\BaseActiveRecord::optimisticLock() for details on how to enable optimistic lock. */class OptimisticLockBehavior extends AttributeBehavior{    /**     * {@inheritdoc}     *     * In case of `null` value it will be directly parsed from [[\yii\web\Request::getBodyParam()|getBodyParam()]] or set to 0.     */    public $value;    /**     * {@inheritdoc}     */    public $skipUpdateOnClean = false;    /**     * @var string the attribute name holding the version value.     */    private $_lockAttribute;    /**     * {@inheritdoc}     */    public function attach($owner)    {        parent::attach($owner);        if (empty($this->attributes)) {            $lock = $this->getLockAttribute();            $this->attributes = array_fill_keys(array_keys($this->events()), $lock);        }    }    /**     * {@inheritdoc}     */    public function events()    {        return Yii::$app->request instanceof \yii\web\Request ? [            BaseActiveRecord::EVENT_BEFORE_INSERT => 'evaluateAttributes',            BaseActiveRecord::EVENT_BEFORE_UPDATE => 'evaluateAttributes',            BaseActiveRecord::EVENT_BEFORE_DELETE => 'evaluateAttributes',        ] : [];    }    /**     * Returns the column name to hold the version value as defined in [[\yii\db\BaseActiveRecord::optimisticLock()|optimisticLock()]].     * @return string the property name.     * @throws InvalidCallException if [[\yii\db\BaseActiveRecord::optimisticLock()|optimisticLock()]] is not properly configured.     * @since 2.0.16     */    protected function getLockAttribute()    {        if ($this->_lockAttribute) {            return $this->_lockAttribute;        }        /* @var $owner BaseActiveRecord */        $owner = $this->owner;        $lock = $owner->optimisticLock();        if ($lock === null || $owner->hasAttribute($lock) === false) {            throw new InvalidCallException("Unable to get the optimistic lock attribute. Probably 'optimisticLock()' method is misconfigured.");        }        $this->_lockAttribute = $lock;        return $lock;    }    /**     * {@inheritdoc}     *     * In case of `null`, value will be parsed from [[\yii\web\Request::getBodyParam()|getBodyParam()]] or set to 0.     */    protected function getValue($event)    {        if ($this->value === null) {            $request = Yii::$app->getRequest();            $lock = $this->getLockAttribute();            $formName = $this->owner->formName();            $formValue = $formName ? ArrayHelper::getValue($request->getBodyParams(), $formName . '.' . $lock) : null;            $input = $formValue ?: $request->getBodyParam($lock);            $isValid = $input && (new NumberValidator())->validate($input);            return $isValid ? $input : 0;        }        return parent::getValue($event);    }    /**     * Upgrades the version value by one and stores it to database.     *     * ```php     * $model->upgrade();     * ```     * @throws InvalidCallException if owner is a new record.     * @since 2.0.16     */    public function upgrade()    {        /* @var $owner BaseActiveRecord */        $owner = $this->owner;        if ($owner->getIsNewRecord()) {            throw new InvalidCallException('Upgrading the model version is not possible on a new record.');        }        $lock = $this->getLockAttribute();        $version = $owner->$lock ?: 0;        $owner->updateAttributes([$lock => $version + 1]);    }}
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