Magento 2: Set Custom product attribute value programmatically on product save

Question

How to set a product's custom attribute on save? I have used the event/observer way but nothing works.

Answer 1

Official method should work, but Not

The official method setCustomAttribute($attributeCode, $attributeValue) below should work but NOT because the official bug https://github.com/magento/magento2/issues/4703.

The bug doesn't fix yet in version 2.2.3.

$product = $this->productRepository->getById($productId);
$product->setCustomAttribute($attributeCode, $attributeValue);
$this->productRepository->save($product);

Temporary method

After many debug and tries, I found the method $product->setData($attributeCode, $attributeValue) below could set custom attribute successfully, it is a temporary method.

Hope it could help you. Any better way is welcome to post :)

private $productRepository;
public function __construct(
    \Magento\Catalog\Api\ProductRepositoryInterface $productRepository
) {
    $this->productRepository = $productRepository;
}
public function updateProductAttribute($productId)
{
    $attributeCode = "Attribute_code";
    $attributeValue = "Attribute Value Here";
    $product = $this->productRepository->getById($productId);
    //$product->setCustomAttribute($attributeCode, $attributeValue);
    $product->setData($attributeCode, $attributeValue);
    $this->productRepository->save($product);
}

Answer 2

Rather using the setcustomattribute function you can just use this: Suppose your attribute code is inbound.

$product = $this->productRepository->getById($productId);
$product->setInbound($attributeValue);
$this->productRepository->save($product);

Answer 3

The most upvoted answer didn't work for me on Magento 2.3.5 while creating a new product programatically.

Most probably because it depends on the type of custom attribute. If it's a dropdown or swatch, then you need to set the option ID, not the value.

So this is the method I ended up using (for the color attribute):

$product = $objectManager->create('Magento\Catalog\Model\Product');
$color = 'Black';
$product_resource = $product->getResource();
$color_attribute = $product_resource->getAttribute('color');
if ($color_attribute->usesSource()) {
    $color_option_id = $color_attribute->getSource()->getOptionId($color);
    if ($color_option_id != '') {
        $product->setData('color', $color_option_id);
    }
}       
... // set other attributes 
$product->save();

Answer 4

I would use event observer catalog_product_save_before to avoid loading and saving product separately extra time.

/** @var \Magento\Catalog\Model\Product $product */
$product = $observer->getData('product');
$product->setData('my_attribute', 'Some value');

Or plugin \Magento\Catalog\Model\ResourceModel\Product::beforeSave, because indexers already declare plugins on this method (for example, \Magento\CatalogRule\Plugin\Indexer\Product\Save\ApplyRules::afterSave);

Answer 5

For Magento 2.3.2
"Save" method of calss "Magento\Catalog\Api\ProductRepositoryInterface" not worked for me. Gives "Unique constraint violation found error".

Method "updateAttributes" of class "Magento\Catalog\Model\ResourceModel\Product\Action" worked fine for me.

Answer 6

    <?php
namespace vendor\module\Observer;

class ProductSaveAfter implements \Magento\Framework\Event\ObserverInterface
{
    public function __construct(
        \Magento\Backend\Model\Auth\Session $authSession,
        \Magento\Catalog\Model\ProductFactory $productFactory
    ) {
        $this->authSession = $authSession;
        $this->productFactroy = $productFactory;
    }
    public function execute(\Magento\Framework\Event\Observer $observer)
    {
        $user = $this->authSession->getUser()->getUsername();
        $productId = (int) $observer->getProduct()->getId();
        $product = $this->productFactroy->create()->load($productId);
        $product->addAttributeUpdate("updated_by", $user, 0);//attribute,value,storeid
    }
}

Answer 7

    $objectManager = \Magento\Framework\App\ObjectManager::getInstance(); // instance of object manager
            $product = $objectManager->create('\Magento\Catalog\Model\Product');

            $prod = $product->loadByAttribute('sku', $sku);
$prod->setCustomattribute($value); // name of your custom attribute
$prod->save();