add UniqueSluggableBehavior

to validate the uniqueness of a slug in multiple repositories

src/behaviors/SluggableBehavior.php

@@ -47,8 +47,12 @@ public function init()
     /**
      * @return ActiveRepositoryInterface
      */
-    protected function getRepository()
+    protected function getRepository($interface = null): ActiveRepositoryInterface
     {
+        if (!empty($interface)) {
+            return Yii::createObject($interface);
+        }
+
         return $this->repository;
     }
 

src/behaviors/UniqueSluggableBehavior.php

@@ -0,0 +1,40 @@
+<?php
+
+namespace albertborsos\ddd\behaviors;
+
+use albertborsos\ddd\traits\EvaluateAttributesTrait;
+
+abstract class UniqueSluggableBehavior extends SluggableBehavior
+{
+    use EvaluateAttributesTrait;
+
+    public $ensureUnique = true;
+
+    /**
+     * List of \yii\validators\UniqueValidator configurations to validate the uniqueness of a slug in multiple repositories.
+     * The value of `targetClass` property is ridden from the actual repository.
+     *
+     * ```php
+     *  [
+     *      PageActiveRepositoryInterface::class     => ['targetAttribute' => 'slug', 'filter' => $this->owner && $this->owner->id ? ['NOT', ['id' => $this->owner->id]] : []],
+     *      PageSlugActiveRepositoryInterface::class => ['targetAttribute' => 'slug', 'filter' => $this->owner && $this->owner->id ? ['page_id' => $this->owner->id] : []],
+     *  ]
+     * ```
+     *
+     * @var array
+     */
+    abstract protected function uniqueValidators();
+
+    protected function validateSlug($slug)
+    {
+        foreach ($this->uniqueValidators() as $repositoryInterface => $validator) {
+            $this->uniqueValidator = array_merge($validator, ['targetClass' => $this->getRepository($repositoryInterface)->getDataModelClass()]);
+            $isUnique = parent::validateSlug($slug);
+            if (!$isUnique) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+}