Magento 2 - Losing data with extension attributes in bundle options collection

Question

I am using Magento 2.1.4 I add a new column required_total on table catalog_product_bundle_option

I created the extension_attributes.xmlfile

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Api/etc/extension_attributes.xsd">
    <extension_attributes for="Magento\Bundle\Api\Data\OptionInterface">
        <attribute code="required_total" type="int"/>
    </extension_attributes>
</config>

I did bin/magento setup:di:compile to generate the interface \Magento\Bundle\Api\Data\OptionExtensionInterface in var/generation folder.

In admin edit form of a bundled product Magento use $this->optionsRepository->getList() to retrieve bundle options.
Here Magento will use populateWithArray method to hydrate the collection entities.

/**
 * @param \Magento\Catalog\Api\Data\ProductInterface $product
 * @return \Magento\Bundle\Api\Data\OptionInterface[]
 */
public function getItems(\Magento\Catalog\Api\Data\ProductInterface $product)
{
    $optionCollection = $this->type->getOptionsCollection($product);
    [...]
    /** @var \Magento\Bundle\Model\Option $option */
    foreach ($optionCollection as $option) {
        [...]
        /** @var \Magento\Bundle\Api\Data\OptionInterface $optionDataObject */
        $optionDataObject = $this->optionFactory->create();

        \Zend_Debug::dump($option->debug(), 'before populate');
        $this->dataObjectHelper->populateWithArray(
            $optionDataObject,
            $option->getData(),
            '\Magento\Bundle\Api\Data\OptionInterface'
        );
        \Zend_Debug::dump($optionDataObject->debug(), 'after populate');
        die;

        $optionDataObject->setOptionId($option->getOptionId())
            ->setTitle($option->getTitle() === null ? $option->getDefaultTitle() : $option->getTitle())
            ->setDefaultTitle($option->getDefaultTitle())
            ->setSku($product->getSku())
            ->setProductLinks($productLinks);
        $optionList[] = $optionDataObject;
    }
    return $optionList;
}

Here is the debug

before populate array(10) {
  ["option_id"] => string(2) "17"
  ["parent_id"] => string(3) "719"
  ["required"] => string(1) "1"
  ["position"] => string(1) "1"
  ["type"] => string(8) "checkbox"
  ["required_total"] => string(1) "2"
  ["default_title"] => string(16) "Foo"
  ["title"] => string(16) "Foo"
}

after populate array(5) {
  ["option_id"] => string(2) "17"
  ["required"] => string(1) "1"
  ["position"] => string(1) "1"
  ["type"] => string(8) "checkbox"
  ["title"] => string(16) "Foo"
}

As you can see my new column is not set, as far as I understand looking at \Magento\Framework\Api\DataObjectHelper::_setDataValues it is because :

• setter does not exist in \Magento\Bundle\Api\Data\OptionInterface
• attribute is not a custom attribute

Because of that I can not retrieve my attribute value and so can not edit it in the admin edit form.

Of course $option->getExtensionAttributes() is empty.

What are my solutions here :

• using a plugin to make $optionDataObject->setRequiredTotal($option->getRequiredTotal()) at the end of the function ?
• Am I using the extension attributes the wrong way ?
• Am I missing something ?

Answer 1

The documentation for extension attributes is not quite clear on what's the right way to use them and it seems like each entity type does it in a slightly different way.

That being said, from my experience you have to create plugins to populate the extension attributes, and also to save them. It is not done automatically.

Take a look at Magento\GiftMessage\Model\Plugin\OrderGet and Magento\GiftMessage\Model\Plugin\OrderSave for an example.

Answer 2

You should process extension attributes manually. But, for repository and collections there are different ways. Magento...

Common action: create extension attributes declaration.

For repo:

1. Create plugin for init object.

Plugin:

<type name="Magento\Sales\Api\Data\OrderInterface">

Code:

public function afterGetExtensionAttributes(
    OrderInterface $entity,
    OrderExtensionInterface $extension = null
) {
    if ($extension === null) {
        $extension = $this->extensionFactory->create();
    }

    return $extension;
}

2. Add plugin-handlers for getting and saving the attributes.

For Collections: use plugins for preload custom fields from db and observers (after collection load) for filling the attributes.

---

In conclusion, for each new entity you have to do all steps again.