SPONSOR: Amadeco

This module by Amadeco extends Smile ElasticSuite (https://github.com/Smile-SA/elasticsuite) to add an advanced stock filter in the layered navigation.

• Adds a dedicated stock filter in the layered navigation
• Intelligent handling of stock status based on Magento's backorders configuration
• Improves user experience by showing accurate product availability
• Provides clear "In Stock" and "Out of Stock" filter options
• Fully compatible with Magento's MSI (Multi-Source Inventory)

composer require amadeco/module-elasticsuite-stock
bin/magento module:enable Amadeco_ElasticsuiteStock
bin/magento setup:upgrade
bin/magento setup:di:compile
bin/magento cache:clean
bin/magento indexer:reindex catalogsearch_fulltext

• PHP 8.3+
• Magento 2.4.x
• Smile ElasticSuite 2.8 or higher
• Smile ElasticSuite Rating 2.3 or higher

Go to Stores > Configuration > ElasticSuite > Stock Filter

Configure the following options:

• Display Out Of Stock Filter: When enabled, shows the "Out of Stock" option in the layered navigation. When disabled, only the "In Stock" option is shown.

After installation and configuration, the stock filter will automatically appear in the layered navigation on category pages and search results pages (remember to reindex after installation).

This module creates an indexed attribute stock_status that handles stock differently based on your Magento configuration:

• Uses Magento's native stock status logic
• Products are either in stock or out of stock, as determined by Magento's inventory system

• Enhanced behavior: Determines availability based on actual quantity
• Products with quantity > 0 are marked as "In Stock"
• Products with quantity ≤ 0 are marked as "Out of Stock" (even if Magento would allow them to be ordered)
• This gives customers a clearer view of which products have physical inventory

The filter provides these options:

1. In Stock:

   • Shows products with positive inventory when backorders are enabled
   • Follows standard Magento stock status rules when backorders are disabled

2. Out of Stock (can be hidden via configuration):

   • Shows products with zero or negative inventory when backorders are enabled
   • Shows products marked as out of stock when backorders are disabled

This approach helps customers find products based on actual availability while respecting your inventory settings.

This module leverages the existing stock.is_in_stock and stock.qty fields from quantity_and_stock_status attribute and creates a derived stock_status field that combines this information intelligently.

Instead of relying on Magento's quantity_and_stock_status attribute (which has limitations for filtering ; see reported issue: magento/magento2#33453), our module:

• Creates a dedicated filterable attribute for stock status
• Applies specific logic when backorders are enabled to show actual inventory status
• Integrates seamlessly with ElasticSuite's facet filtering system

Smile_ElasticsuiteRating is a required dependency due to how Magento's preference system works:

Both modules (Rating and our Stock module) attempt to override Smile\ElasticsuiteCatalog\Model\Layer\FilterList using preferences. In Magento's preference system, when multiple modules declare a preference for the same class, only the last one loaded (based on module loading order) takes effect. If Smile_ElasticsuiteRating is installed but our module's preference isn't properly applied, our stock filter won't appear in the layered navigation.

To solve this conflict, we must:

<preference for="Smile\ElasticsuiteCatalog\Model\Layer\FilterList" 
            type="Amadeco\ElasticsuiteStock\Model\Layer\FilterList"/>
            
<preference for="Smile\ElasticsuiteRating\Model\Layer\FilterList" 
            type="Amadeco\ElasticsuiteStock\Model\Layer\FilterList"/>

This approach requires Smile_ElasticsuiteRating to be present since we're explicitly overriding its class. Without it, Magento would throw a fatal error when trying to resolve this preference.

Note: We recognize that the current dependency on Smile_ElasticsuiteRating is not ideal. In a future release, we plan to implement a more flexible architecture.

This module is licensed under the Open Software License ("OSL") v3.0. See the LICENSE.txt file for details.