How to Create Custom Indexer in Magento 2?

Magento 2 is a powerful platform, but sometimes your store needs a custom indexer to enhance data retrieval and performance. When default indexers aren't enough, creating a custom one can streamline your processes. This guide will show you how to create a custom indexer in Magento 2.

Step 1: Define Your Magento 2 Custom Indexer

The first step is to define your custom indexer by creating an indexer configuration file. This file informs Magento about your indexer's identity and functionality. 

Navigate to `etc` and create a new `indexer.xml` file within your custom module. The file should include information like the indexer ID, class, and name.

Step 2: Develop the Indexer Class

Next, you'll need to create an indexer class, which will rebuild and refresh data. 

This class should implement the `\Magento\Framework\Indexer\ActionInterface` and `\Magento\Framework\Mview\ActionInterface`.

Overwrite the required methods such as `execute` to describe the indexer's actions.

Step 3: Set Up a Cron Job (Optional)

This step is optional, but it’s recommended for the reindexing process automation. 

Configure a cron job within your custom module's `crontab.xml` to periodically reindex without any manual intervention.

Step 4: Test Your Indexer

Finally, test your customindexer to ensure it functions correctly and optimizes data as expected.

You can execute your indexer via the command line using Magento’s standard reindexing commands:

For those who want to simplify the process of reindexing, tools like Reindex from Admin for Magento 2 can offer user-friendly solutions to manage the indexing process more efficiently.

With these steps you can effectively extend Magento 2’s indexing capabilities to better suit your business needs, enhancing efficiency and customer experience.