<?php
/**
* CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
* Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
*
* Licensed under The MIT License
* For full copyright and license information, please see the LICENSE.txt
* Redistributions of files must retain the above copyright notice.
*
* @copyright Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
* @link https://cakephp.org CakePHP(tm) Project
* @since 3.0.0
* @license https://opensource.org/licenses/mit-license.php MIT License
*/
namespace Cake\ORM\Rule;
use Cake\Datasource\EntityInterface;
/**
* Checks that a list of fields from an entity are unique in the table
*/
class IsUnique
{
/**
* The list of fields to check
*
* @var string[]
*/
protected $_fields;
/**
* The options to use.
*
* @var array
*/
protected $_options;
/**
* Constructor.
*
* ### Options
*
* - `allowMultipleNulls` Set to false to disallow multiple null values in
* multi-column unique rules. By default this is `true` to emulate how SQL UNIQUE
* keys work.
*
* @param string[] $fields The list of fields to check uniqueness for
* @param array $options The additional options for this rule.
*/
public function __construct(array $fields, array $options = [])
{
$this->_fields = $fields;
$this->_options = $options + ['allowMultipleNulls' => true];
}
/**
* Performs the uniqueness check
*
* @param \Cake\Datasource\EntityInterface $entity The entity from where to extract the fields
* where the `repository` key is required.
* @param array $options Options passed to the check,
* @return bool
*/
public function __invoke(EntityInterface $entity, array $options)
{
if (!$entity->extract($this->_fields, true)) {
return true;
}
$allowMultipleNulls = $this->_options['allowMultipleNulls'];
$alias = $options['repository']->getAlias();
$conditions = $this->_alias($alias, $entity->extract($this->_fields), $allowMultipleNulls);
if ($entity->isNew() === false) {
$keys = (array)$options['repository']->getPrimaryKey();
$keys = $this->_alias($alias, $entity->extract($keys), $allowMultipleNulls);
if (array_filter($keys, 'strlen')) {
$conditions['NOT'] = $keys;
}
}
return !$options['repository']->exists($conditions);
}
/**
* Add a model alias to all the keys in a set of conditions.
*
* Null values will be omitted from the generated conditions,
* as SQL UNIQUE indexes treat `NULL != NULL`
*
* @param string $alias The alias to add.
* @param array $conditions The conditions to alias.
* @param bool $multipleNulls Whether or not to allow multiple nulls.
* @return array
*/
protected function _alias($alias, $conditions, $multipleNulls)
{
$aliased = [];
foreach ($conditions as $key => $value) {
if ($multipleNulls) {
$aliased["$alias.$key"] = $value;
} else {
$aliased["$alias.$key IS"] = $value;
}
}
return $aliased;
}
}