Magento 2 api - How to get layer navigation filters available in rest api?

Question

I have someone issue in api magento 2. I need get layer navigation data available in product collection ( current category , search product ) but I don't know magento 2 api available it or not . I have create new custom api using Magento\Catalog\Model\Layer\Resolver but it not work . Any one can help me ?

thanks guys

Answer 1

There are 2 methods to achieve this

First one

Filter.php (api model)

    public function __construct(\Magento\Framework\Webapi\Rest\Request 
        $request){
            
                $this->_request         = $request;
        }


/**
     * Retrieve filterlist
     *
     * @api
     * @return array
     */
    public function retrieve(){     

        $category = $this->_request->getParam('categoryId');

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

        $filterableAttributes = $objectManager->getInstance()->get(\Magento\Catalog\Model\Layer\Category\FilterableAttributeList::class);

        $appState = $objectManager->getInstance()->get(\Magento\Framework\App\State::class);
        $layerResolver = $objectManager->getInstance()->get(\Magento\Catalog\Model\Layer\Resolver::class);
        $filterList = $objectManager->getInstance()->create(
            \Magento\Catalog\Model\Layer\FilterList::class,
                [
                    'filterableAttributes' => $filterableAttributes
                ]
            );      

            $layer = $layerResolver->get();
            $layer->setCurrentCategory($category);
            $filters = $filterList->getFilters($layer);
            $maxPrice = $layer->getProductCollection()->getMaxPrice();
            $minPrice = $layer->getProductCollection()->getMinPrice();  

        $i = 0;
       foreach($filters as $filter)
       {
           //$availablefilter = $filter->getRequestVar(); //Gives the request param name such as 'cat' for Category, 'price' for Price
           $availablefilter = (string)$filter->getName(); //Gives Display Name of the filter such as Category,Price etc.
           $items = $filter->getItems(); //Gives all available filter options in that particular filter
           $filterValues = array();
           $j = 0;
           foreach($items as $item)
           {
               

               $filterValues[$j]['display'] = strip_tags($item->getLabel());
               $filterValues[$j]['value']   = $item->getValue();
               $filterValues[$j]['count']   = $item->getCount(); //Gives no. of products in each filter options
               $j++;
           }
           if(!empty($filterValues) && count($filterValues)>1)
           {
               $filterArray['availablefilter'][$availablefilter] =  $filterValues;
           }
           $i++;
       }  

       
        echo json_encode($filterArray);
        exit;

    }

Sample out put of this code will be:

{
    "availablefilter": {
        "Climate": [
            {
                "display": "All-Weather",
                "value": "202",
                "count": "1"
            },
            {
                "display": "Cool",
                "value": "204",
                "count": "1"
            }
        ],
        "Manufacturer": [
            {
                "display": "Azzedine Alaïa",
                "value": "216",
                "count": "1"
            },
            {
                "display": "Balenciaga",
                "value": "217",
                "count": "1"
            }
        ],
        "Material": [
            {
                "display": "Cotton",
                "value": "33",
                "count": "1"
            },
            {
                "display": "Nylon",
                "value": "37",
                "count": "1"
            }
        ],

Second method

public function __construct(
        \Magento\Catalog\Model\ResourceModel\Product\Attribute\CollectionFactory $productAttributeCollectionFactory
    ) {
        $this->productAttributeCollectionFactory = $productAttributeCollectionFactory;
    }
 
    public function getFilterableAttributes()
    {
        /** @var \Magento\Catalog\Model\ResourceModel\Product\Attribute\Collection $productAttributes */
        $productAttributes = $this->productAttributeCollectionFactory->create();
        $productAttributes->addFieldToFilter(
            ['is_filterable', 'is_filterable_in_search'],
            [[1, 2], 1]
        );
 
        return $productAttributes;
    }

Answer 2

Unless your email address ends in '@magento.com', you should not be using Object Manager in your code. No ifs, no buts. This is how I went about achieving this:

<?php
namespace Vendor\Module\Model;

use Magento\Catalog\Model\Layer\Category\FilterableAttributeList;
use Magento\Catalog\Model\Layer\FilterListFactory;
use Magento\Catalog\Model\Layer\Resolver as layerResolver;
use Magento\Catalog\Model\Product\Attribute\Source\Status;
use Magento\Catalog\Model\Product\Visibility;

class YourClass
{
    /**
     * @var \Magento\Catalog\Model\Layer\Category\FilterableAttributeList
     */
    protected $filterableAttributes;
    /**
     * @var \Magento\Catalog\Model\Layer\Resolver
     */
    protected $layerResolver;
    /**
     * @var \Magento\Catalog\Model\Layer\FilterListFactory
     */
    protected $filterListFactory;

    /**
     * Your constructor.
     * @param \Magento\Catalog\Model\Layer\Category\FilterableAttributeList $filterableAttributes
     * @param \Magento\Catalog\Model\Layer\Resolver $layerResolver
     * @param FilterListFactory $filterListFactory
     */
    public function __construct(
        FilterableAttributeList $filterableAttributes,
        layerResolver $layerResolver,
        FilterListFactory $filterListFactory
    ) {
        $this->filterableAttributes = $filterableAttributes;
        $this->layerResolver = $layerResolver;
        $this->filterListFactory = $filterListFactory;
    }

    /**
     * Get filters for a category page.
     * @param string $category_id
     * @return array
     * @throws \Magento\Framework\Exception\LocalizedException
     */
    public function getCategoryFilters(string $category_id): array
    {
        $returnFilters = [];
        $filterableAttributes = $this->filterableAttributes;
        $layerResolver = $this->layerResolver;
        $filterList = $this->filterListFactory->create(['filterableAttributes' => $filterableAttributes]);
        $layer = $layerResolver->get();
        $layer->setCurrentCategory($category_id);
        $layer->getProductCollection()
            ->addAttributeToFilter("visibility", ["neq" => Visibility::VISIBILITY_NOT_VISIBLE])
            //optional to exclude product attributes of non visible products
            ->addAttributeToFilter("status", ["eq" => Status::STATUS_ENABLED]);
            //optional to exclude product attributes of disabled products
        foreach ($filterList->getFilters($layer) as $filter) {
            $values = [];
            foreach ($filter->getItems() as $item) {
                $values[] = [
                    "display" => strip_tags($item->getLabel()), //strip_tags is optional, but there's HTML in some of my labels
                    "value" => $item->getValue(),
                    "count" => $item->getCount()
                ];
            }
            if (!empty($values)) {
                $returnFilters[] = [
                    "attr_code" => $filter->getRequestVar(),
                    "attr_label" => $filter->getName(),
                    "values" => $values
                ];
            }
        }
        return $returnFilters;
    }
}

Answer 3

Get request value in json format like below

{
        "category_id":"36" //pass category which you want
}

below is the Filterattributes.php (api model)

<?php
    namespace HIT\Customer\Model;
    use HIT\Customer\Api\FilterAttributesInterface;
    use Magento\Framework\Encryption\EncryptorInterface;
    
    class FilterAttributes extends \Magento\Framework\Model\AbstractModel implements FilterAttributesInterface
    {
        
    
    
        public function __construct(
           
        ){
           
        }
    
        /**
         * Returns greeting message to user
         *
         * @api
         * @param string $name Users name.
         * @return string Greeting message with users name.
         */
        public function filterAttributes() {
           
            $json = file_get_contents('php://input');
            $post = json_decode($json);
            
            $objectManager = \Magento\Framework\App\ObjectManager::getInstance();
            $category = $objectManager->create('Magento\Catalog\Model\Category')->load($this->_request->getParam($post->category_id));
            $filterableAttributes = $objectManager->getInstance()->get(\Magento\Catalog\Model\Layer\Category\FilterableAttributeList::class);
    
            $appState = $objectManager->getInstance()->get(\Magento\Framework\App\State::class);
            $layerResolver = $objectManager->getInstance()->get(\Magento\Catalog\Model\Layer\Resolver::class);
            $filterList = $objectManager->getInstance()->create(
                \Magento\Catalog\Model\Layer\FilterList::class,
                    [
                        'filterableAttributes' => $filterableAttributes
                    ]
                );      
    
                $layer = $layerResolver->get();
                $layer->setCurrentCategory($category);
                $filters = $filterList->getFilters($layer);
                $maxPrice = $layer->getProductCollection()->getMaxPrice();
                $minPrice = $layer->getProductCollection()->getMinPrice();  
    
            $i = 0;
            $filterAttrs = [];
           foreach($filters as $filter)
           {
                $values = [];
                $attr_code = (string)$filter->getRequestVar();
                $attr_label = (string)$filter->getName();
                $items = $filter->getItems(); //Gives all available filter options in that particular filter
               foreach($items as $item)
               {
    
                    $values[] = array("display"=>strip_tags($item->getLabel()),
                                        "value"=>$item->getValue(),
                                        "count"=>$item->getCount());
               }
               if(!empty($values) && count($values)>1)
               {
                   $filterAttrs[]=array("attr_code"=>$attr_code,
                                    "attr_label"=>$attr_label,
                                    "values"=>$values);
               }
    
           }  
    
    
           if(count($filters)>0){
            $data['status'] = "true";
            $data['filters'] = $filterAttrs;
           }else{
            $data['status'] = "false";
            $data['msg'] = "No Filters Found";
           }
     
       
    
             echo json_encode($data, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT );// str_replace('\/','/',json_encode($data)); 
            exit();
        }
    
    
    
    }