How can we return an array of search results in APIs Magento 2

Question

I need to return array of search results and so far I did this.

DashBoardInterface.php

<?php
/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */
namespace Vendor\CustomAPIs\Api\Data;

/**
 * DashBoardInterface.
 * @api
 * @since 100.0.2
 */
interface DashBoardInterface
{

    const KEY_SLIDES = 'slides';
    const KEY_TOP_CATEGORIES = 'top_categories';
    const KEY_CATEGORIES = 'categories';
    const KEY_PRODUCTS = 'products';

    /**
     * Get Slides
     *
     * @return \Vendor\CustomAPIs\Api\Data\SlidesInterface[]
     */
    public function getSlides();

    /**
     * Set Slides
     *
     * @param \Magento\Framework\Api\SearchCriteriaInterface $searchCriteria 
     * @return $this
     */
    public function setSlides($searchCriteria);

    /**
     * Get Top Categories
     *
     * @return \Magento\Catalog\Api\Data\CategorySearchResultsInterface
     */
    public function getTopCategories();

    /**
     * Set Top Categories
     *
     * @param \Magento\Framework\Api\SearchCriteriaInterface $searchCriteria
     * @return $this
     */
    public function setTopCategories($searchCriteria);

    /**
     * Get Featured Categories
     *
     * @return \Magento\Catalog\Api\Data\CategorySearchResultsInterface[]
     */
    public function getCategories();

    /**
     * Set Featured Categories
     *
     * @param \Magento\Framework\Api\SearchCriteriaInterface $searchCriteria
     * @return $this
     */
    public function setCategories($searchCriteria);

    /**
     * Get Hot Seller Products
     *
     * @return \Magento\Catalog\Api\Data\ProductSearchResultsInterface
     */
    public function getProducts();

    /**
     * Set Hot Seller Products
     *
     * @param \Magento\Framework\Api\SearchCriteriaInterface $searchCriteria
     * @return $this
     */
    public function setProducts($searchCriteria);

}

DashBoardRepositoryInterface.php

<?php

namespace Vendor\CustomAPIs\Api;

/**
 * Interface DashBoardRepositoryInterface
 * @package Vendor\CustomAPIs\Api
 */
interface DashBoardRepositoryInterface
{
    const FILE_DIR = 'aw_rbslider/slides';
    const PRODUCT_LISTING = 'product_listing';
    const ACTIVE_BANNER = 'banner_tabs/general/active_banner';
    const ACTIVE_CATEGORY_SLIDER = 'banner_tabs/general/category_options';

    /**
     * Get DashBoard Data
     *
     * @return \Vendor\CustomAPIs\Api\Data\DashBoardInterface
     */
    public function getDashboardData();

}

DashBoardRepository.php

<?php

namespace Vendor\CustomAPIs\Model;

use Vendor\CustomAPIs\Api\DashBoardRepositoryInterface;
use Magento\Framework\Exception\LocalizedException;
use Magento\Framework\Exception\EmailNotConfirmedException;
use Magento\Framework\Exception\InvalidEmailOrPasswordException;
use Magento\Framework\Exception\InputException;

/**
 * Class DashBoardRepository
 * @package Vendor\CustomAPIs\Model
 */
class DashBoardRepository implements DashBoardRepositoryInterface 
{
    /**
     * {@inheritdoc}
     */
    public function getDashboardData() 
    {   
        $finalData = [
           'slides' =>  $this->getFilteredSlides(),
      //     'top_categories' =>  $this->getFilteredCategories('level', 2),
           'categories' =>  $this->getFilteredCategories(),
           'products' =>  $this->getFilteredProducts('sale'),
        ];

        $dashBoardObject = $this->dashboardFactory->create();
        $this->dataObjectHelper->populateWithArray(
            $dashBoardObject,
            $finalData,
            \Vendor\CustomAPIs\Api\Data\DashBoardInterface::class
        );
        return $dashBoardObject;
    }


    private function getFilteredCategories()
    {
        $categoryTypes = $this->scopeConfig->getValue(self::ACTIVE_CATEGORY_SLIDER, \Magento\Store\Model\ScopeInterface::SCOPE_STORE);
      //  echo "<pre>";print_r(json_decode($categoryTypes));exit;
        $categories = [];
        foreach(json_decode($categoryTypes) as $categoryType) {
            $this->searchCriteriaBuilder->addFilters(
                    [
                                $this->filterBuilder
                                ->setField('is_active')
                                ->setConditionType('eq')
                                ->setValue(true)
                                ->create(),
                    ]
            );
            $this->searchCriteriaBuilder->addFilters(
                    [
                                $this->filterBuilder
                                ->setField('slider_category_type')
                                ->setConditionType('eq')
                                ->setValue($categoryType->option_value)
                                ->create(),
                    ]
            );

            $searchCriteria = $this->searchCriteriaBuilder->create();
            $categories[$categoryType->option_value] = $this->categoryList->getList($searchCriteria);
        }

//        foreach ($searchResult->getItems() as $item)
//        {
//            echo "<pre>";print_r($item->getTotalCount());
//        }
//        exit;
        $objectManager = \Magento\Framework\App\ObjectManager::getInstance();
        $objectManager->create('Psr\Log\LoggerInterface')->debug('data', [$categories]);
        return $categories;
    }

}

Now issue in that code is when I return categories from getFilteredCategories() it returns array of object and it throws error that populateWithArray function expect parameter 2 be array object given. I know it is due to I defined array of CategorySearchResultsInterface[] in DashBoardInterface. Basically I want that categories should return like.

slides :{}
---
---
categories : {
   featured_categories : {
     items : [
        {},
        {}
     ]
   },
   new_categories : {
     items : [
        {},
        {}
     ]
   }
}

And same will be for products. Please help if anyone have done this before.

Answer 1

I just fixed this. Need to create one more interface for this.

CategoryArrayItemInterface

<?php
namespace Vendor\CustomAPIs\Api\Data;

/**
 * Interface which represents associative array item.
 */
interface CategoryArrayItemInterface
{
    const KEY = "key";
    const KEY_VALUE = "value";

    /**
     * Get key
     * 
     * @return string
     */
    public function getKey();

    /**
     * Set key
     * 
     * @return string
     */
    public function setKey($key);

    /**
     * Get value
     * 
     * @return \Magento\Catalog\Api\Data\CategorySearchResultsInterface
     */
    public function getValue();

    /**
     * Set value
     * 
     * @param \Magento\Framework\Api\SearchCriteriaInterface $searchCriteria
     * @return $this
     */
    public function setValue($searchCriteria);
}

and use this interface in my DashBoardInterface like below.

/**
 * Get Categories
 *
 * @return \Vendor\Module\Api\Data\CategoryArrayItemInterface[]
 */
public function getCategories();

/**
 * Set Categories
 *
 * @param \Magento\Framework\Api\SearchCriteriaInterface $searchCriteria
 * @return $this
 */
public function setCategories($searchCriteria);

and update getFilteredCategories() function like below.

private function getFilteredCategories()
{
    $categoryTypes = $this->scopeConfig->getValue(self::ACTIVE_CATEGORY_SLIDER, \Magento\Store\Model\ScopeInterface::SCOPE_STORE);
    $categories = [];
    foreach(explode(',', $categoryTypes) as $categoryType) {
        $this->searchCriteriaBuilder->addFilters(
                [
                            $this->filterBuilder
                            ->setField('is_active')
                            ->setConditionType('eq')
                            ->setValue(true)
                            ->create(),
                ]
        );
        $this->searchCriteriaBuilder->addFilters(
                [
                            $this->filterBuilder
                            ->setField('slider_category_type')
                            ->setConditionType('eq')
                            ->setValue($categoryType)
                            ->create(),
                ]
        );

        $searchCriteria = $this->searchCriteriaBuilder->create();
        $categories[] = [
            'key' => $categoryType,
            'value' => $this->categoryList->getList($searchCriteria)
        ];
    }

    return $categories;
}

Thanks to @Alex Paliarush for this exmaple. Let me know if anyone needs more explanation on this.