1: <?php
  2: /**
  3:  * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
  4:  * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
  5:  *
  6:  * Licensed under The MIT License
  7:  * For full copyright and license information, please see the LICENSE.txt
  8:  * Redistributions of files must retain the above copyright notice.
  9:  *
 10:  * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
 11:  * @link          https://cakephp.org CakePHP(tm) Project
 12:  * @since         3.0.0
 13:  * @license       https://opensource.org/licenses/mit-license.php MIT License
 14:  */
 15: namespace Cake\ORM\Rule;
 16: 
 17: use Cake\Datasource\EntityInterface;
 18: 
 19: /**
 20:  * Checks that a list of fields from an entity are unique in the table
 21:  */
 22: class IsUnique
 23: {
 24:     /**
 25:      * The list of fields to check
 26:      *
 27:      * @var string[]
 28:      */
 29:     protected $_fields;
 30: 
 31:     /**
 32:      * The options to use.
 33:      *
 34:      * @var array
 35:      */
 36:     protected $_options;
 37: 
 38:     /**
 39:      * Constructor.
 40:      *
 41:      * ### Options
 42:      *
 43:      * - `allowMultipleNulls` Set to false to disallow multiple null values in
 44:      *   multi-column unique rules. By default this is `true` to emulate how SQL UNIQUE
 45:      *   keys work.
 46:      *
 47:      * @param string[] $fields The list of fields to check uniqueness for
 48:      * @param array $options The additional options for this rule.
 49:      */
 50:     public function __construct(array $fields, array $options = [])
 51:     {
 52:         $this->_fields = $fields;
 53:         $this->_options = $options + ['allowMultipleNulls' => true];
 54:     }
 55: 
 56:     /**
 57:      * Performs the uniqueness check
 58:      *
 59:      * @param \Cake\Datasource\EntityInterface $entity The entity from where to extract the fields
 60:      *   where the `repository` key is required.
 61:      * @param array $options Options passed to the check,
 62:      * @return bool
 63:      */
 64:     public function __invoke(EntityInterface $entity, array $options)
 65:     {
 66:         if (!$entity->extract($this->_fields, true)) {
 67:             return true;
 68:         }
 69:         $allowMultipleNulls = $this->_options['allowMultipleNulls'];
 70: 
 71:         $alias = $options['repository']->getAlias();
 72:         $conditions = $this->_alias($alias, $entity->extract($this->_fields), $allowMultipleNulls);
 73:         if ($entity->isNew() === false) {
 74:             $keys = (array)$options['repository']->getPrimaryKey();
 75:             $keys = $this->_alias($alias, $entity->extract($keys), $allowMultipleNulls);
 76:             if (array_filter($keys, 'strlen')) {
 77:                 $conditions['NOT'] = $keys;
 78:             }
 79:         }
 80: 
 81:         return !$options['repository']->exists($conditions);
 82:     }
 83: 
 84:     /**
 85:      * Add a model alias to all the keys in a set of conditions.
 86:      *
 87:      * Null values will be omitted from the generated conditions,
 88:      * as SQL UNIQUE indexes treat `NULL != NULL`
 89:      *
 90:      * @param string $alias The alias to add.
 91:      * @param array $conditions The conditions to alias.
 92:      * @param bool $multipleNulls Whether or not to allow multiple nulls.
 93:      * @return array
 94:      */
 95:     protected function _alias($alias, $conditions, $multipleNulls)
 96:     {
 97:         $aliased = [];
 98:         foreach ($conditions as $key => $value) {
 99:             if ($multipleNulls) {
100:                 $aliased["$alias.$key"] = $value;
101:             } else {
102:                 $aliased["$alias.$key IS"] = $value;
103:             }
104:         }
105: 
106:         return $aliased;
107:     }
108: }
109: