Search criteria builder does not filter an "out_of_stock" products

Question

I am using Magento 2.3, Am filtering the product collection using the search criteria builder with a custom attribute as the filter.

$filter1 = $this->_filterBuilder->setField('custom_item_number')
                ->setValue($itemNumber)
                ->setConditionType('eq')
                ->create();
            $this->_searchCriteriaBuilder->addFilters([$filter1]);
            $searchCriteria = $this->_searchCriteriaBuilder->create();
            $productCollection = $this->_productRepository->getList($searchCriteria)->getItems();

This does not filter the product if it is in out of stock status. If I make the product stock status as "in_stock", it works. Why? And How can I filter the product collection?

Thanks in advance.

Answer 1

It's because stock status was added when product collection is loading. You can see how it works as the following

1. \Magento\Catalog\Model\ProductRepository::getList()

...
$collection->joinAttribute('visibility', 'catalog_product/visibility', 'entity_id', null, 'inner');

        $this->collectionProcessor->process($searchCriteria, $collection);

        $collection->load();// The stock fillter will be added after this

        $collection->addCategoryIds();
...

2. \Magento\CatalogInventory\Model\AddStockStatusToCollection::beforeLoad()

public function beforeLoad(Collection $productCollection, $printQuery = false, $logQuery = false)
    {
        $this->stockHelper->addIsInStockFilterToCollection($productCollection);
        return [$printQuery, $logQuery];
    }

3. \Magento\CatalogInventory\Helper\Stock::addIsInStockFilterToCollection()

public function addIsInStockFilterToCollection($collection)
    {
        $stockFlag = 'has_stock_status_filter';
        if (!$collection->hasFlag($stockFlag)) {
            $isShowOutOfStock = $this->scopeConfig->getValue(
                \Magento\CatalogInventory\Model\Configuration::XML_PATH_SHOW_OUT_OF_STOCK,
                \Magento\Store\Model\ScopeInterface::SCOPE_STORE
            );
            $resource = $this->getStockStatusResource();
            $resource->addStockDataToCollection(
                $collection,
                !$isShowOutOfStock
            );
            $collection->setFlag($stockFlag, true);
        }
    }

As you can see here, Magento has a configuration that allows showing products are out of stock:

If you change Display Out of Stock Products to Yes as my screenshot, you will have all products that include products are out of stock

Answer 2

From your question, my understanding is that, you need to filter the searchCriteria using the AND condition with custom_item_number = $itemNumber AND quantity_and_stock_status=1. Here quantity_and_stock_status stands for the stock status. It's value is 1 for in stock products and 0 for out of stock. You can make theAND query by using the class FilterGroupBuilder So inject the class and make the FilterGroupBuilder object in your constructor.

\Magento\Framework\Api\Search\FilterGroupBuilder $filterGroupBuilder 
$this->_filterGroupBuilder = $filterGroupBuilder;

Then modify your code as follows.

$filter1 = $this->_filterBuilder
->setField('custom_item_number')
->setValue($itemNumber)
->setConditionType('eq')
->create();

$filterGroup1 = $this->_filterGroupBuilder->setFilters([$filter1])->create();

$filter2 = $this->_filterBuilder
    ->setField('quantity_and_stock_status')
    ->setValue(1)  
    ->setConditionType('eq')
    ->create();

$filterGroup2 = $this->_filterGroupBuilder->setFilters([$filter2])->create();

$searchCriteria = $this->_searchCriteriaBuilder->create();
$searchCriteria->setFilterGroups([$filterGroup1, $filterGroup2]);
$productCollection = $this->_productRepository->getList($searchCriteria)->getItems();

Now clear your cache and let me know your result.