Let’s say we have an entity which has some relation with other objects (like comments in order). We would like to save related objects on each parent save. To do this we will need to use \Magento\Framework\Model\ResourceModel\Db\VersionControl\AbstractDb
First create ResourceModel:
namespace Vendor\Module\Model\ResourceModel;
class Parent extends \Magento\Framework\Model\ResourceModel\Db\VersionControl\AbstractDb
{
protected function _construct()
{
$this->_init('vendor_example_parent', 'entity_id');
}
}Then we have to let know Magento how to process relations. To do this we are creating Relation object that will process related objects on each object save
namespace Vendor\Module\Model\ResourceModel\Parent;
use Magento\Framework\Model\ResourceModel\Db\VersionControl\RelationInterface;
class Relation implements RelationInterface
{
/**
* @var \Vendor\Module\Api\ChildRepositoryInterface
*/
protected $childRepository;
public function __construct(
\Vendor\Module\Api\ChildRepositoryInterface $childRepository
) {
$this->childRepository = $childRepository;
}
/**
* @inheritDoc
*/
public function processRelation(\Magento\Framework\Model\AbstractModel $object)
{
/** @var \Vendor\Module\Model\Parent $object */
if (null !== $object->getChilds()) {
/** @var \Vendor\Module\Model\Child $child */
foreach ($object->getChilds() as $child) {
$child->setItemId($child->getId());
$child->setItem($object);
$this->childRepository->save($child);
}
}
}
}After that we are creating virtualType and inject our new created Relation.
<virtualType name="ParentRelationsComposite" type="Magento\Framework\Model\ResourceModel\Db\VersionControl\RelationComposite">
<arguments>
<argument name="relationProcessors" xsi:type="array">
<item name="default" xsi:type="object">Vendor\Magento\Model\ResourceModel\Parent\Relation</item>
</argument>
</arguments>
</virtualType>
<type name="Vendor\Module\Model\ResourceModel\Parent">
<arguments>
<argument name="entityRelationComposite" xsi:type="object">ParentRelationsComposite</argument>
</arguments>
</type>Then we can easily process relations
$parent->addChild($childObject);
$parent->addChild($childObject);
$this->parentRepository->save($parent);