Magento 2 how to get all categories of a product in controller

Question

I am trying to get all categories with their levels of a product through it's ID in my controller which is overriding default magento controller.

Can I get product's category path url through it's id in controller ?

How can I do this?

Answer 1

Try like this,

$objectManager =  \Magento\Framework\App\ObjectManager::getInstance();        

$categoryCollection = $objectManager->get('\Magento\Catalog\Model\ResourceModel\Category\CollectionFactory');
$productRepository = $objectManager->get('\Magento\Catalog\Model\ProductRepository');

$appState = $objectManager->get('\Magento\Framework\App\State');
$appState->setAreaCode('frontend');

$productId = 10001; // YOUR PRODUCT ID
$product = $productRepository->getById($productId);

$categoryIds = $product->getCategoryIds();

$categories = $categoryCollection->create()
                                 ->addAttributeToSelect('*')
                                 ->addAttributeToFilter('entity_id', $categoryIds);

foreach ($categories as $category) {
    echo $category->getName() . '<br>';
}

Answer 2

Try below code :

protected $_productCollectionFactory;
protected $_categoryFactory;
protected $_productRepository;

public function __construct(
    \Magento\Catalog\Model\ResourceModel\Product\CollectionFactory $productCollectionFactory,
    \Magento\Catalog\Model\ProductRepository $productRepository,
    \Magento\Catalog\Model\CategoryFactory $categoryFactory,
    \Magento\Framework\ObjectManagerInterface $objectManager,

    ......... Add other depedencies

) {
    $this->_productRepository = $productRepository;
    $this->_categoryFactory = $categoryFactory;
    $this->_productCollectionFactory = $productCollectionFactory;
    $this->_objectManager = $objectManager;

    ......... Add other depedencies

}

public function execute()
{
    $mainProduct = $this->getProductById($productId);
    $categoryIds = $mainProduct->getCategoryIds();
    $result = [];

    for ($i=0; $i < count($categoryIds); $i++) {
        $eachCat = [
            "id" => $categoryIds[$i], 
            "name" => $this->getCategoryName($categoryIds[$i])
        ];

        array_push($result, $eachCat);
    }

    return $result;
}

public function getProductById($id)
{
    return $this->_productRepository->getById($id);
}

public function getCategoryName($categoryId)
{
    $category = $this->_objectManagerr->create('Magento\Catalog\Model\Category')->load($categoryId);
    return $category->getName();
}