indexer.xml — Indexer Declarations

indexer.xml declares indexers that transform data for fast retrieval.

Basic indexer.xml:

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:noNamespaceSchemaLocation="urn:magento:module:Magento_Indexer:etc/indexer.xsd">
    <indexer id="vendor_product_tag" view_id="vendor_product_tag_view"
              class="Vendor\Module\Model\Indexer\ProductTag" view_type="Magento\Search\Model\SearchEngine">
        <title>Product Tags</title>
        <description>Index product tags for search</description>
    </indexer>
</config>

Indexer attributes:

• id — Unique indexer identifier
• view_id — Associated materialized view
• class — Indexer class implementing IndexerInterface
• view_type — Search engine type

Multiple indexers:

<indexer id="vendor_product_tag" view_id="vendor_product_tag_view"
          class="Vendor\Module\Model\Indexer\ProductTag"
          view_type="Magento\Search\Model\SearchEngine">
    <title>Product Tags</title>
    <description>Index product tags</description>
</indexer>

<indexer id="vendor_category_tag" view_id="vendor_category_tag_view"
          class="Vendor\Module\Model\Indexer\CategoryTag"
          view_type="Magento\Search\Model\SearchEngine">
    <title>Category Tags</title>
    <description>Index category tags</description>
</indexer>

Indexer classes handle data transformation and indexing logic.

Indexer class:

<?php
namespace Vendor\Module\Model\Indexer;

use Magento\Framework\Indexer\ActionInterface;
use Magento\Framework\Mview\ViewInterface;

class ProductTag implements ActionInterface, ViewInterface
{
    public function __construct(
        private \Vendor\Module\Model\ResourceModel\Tag\CollectionFactory $tagCollection,
        private \Magento\Search\Model\Indexer\IndexerFactory $indexerFactory
    ) {}
    
    // ActionInterface: Execute full reindex
    public function executeFull(): void
    {
        $tags = $this->tagCollection->create();
        
        foreach ($tags as $tag) {
            $this->reindexTag($tag->getId());
        }
    }
    
    // ActionInterface: Reindex specific entity
    public function execute($id): void
    {
        $this->reindexTag($id);
    }
    
    // ActionInterface: Reindex multiple entities
    public function executeList(array $ids): void
    {
        foreach ($ids as $id) {
            $this->reindexTag($id);
        }
    }
    
    // ViewInterface: Subscribe to data changes
    public function subscribe(): void
    {
        $this->mview->subscribe('vendor_tag', [$this, 'execute']);
    }
    
    private function reindexTag(int $tagId): void
    {
        // Reindex logic
    }
}

Data provider:

<?php
namespace Vendor\Module\Model\Indexer;

class ProductTagDataProvider
{
    public function getTagsForProduct(int $productId): array
    {
        return $this->tagResource->getTagsByProduct($productId);
    }
}

Indexers operate in three modes: real-time, schedule, and manual.

Real-time mode:

• Updates index immediately on data change
• Best for frequently accessed data
• Higher resource usage

Schedule mode:

• Updates index via cron job
• Lower resource usage
• Data may be slightly stale

Manual mode:

• Only updates on explicit reindex command
• Best for rarely changed data
• Lowest resource usage

Configuring mode:

<!-- In mview.xml -->
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:noNamespaceSchemaLocation="urn:magento:framework:Mview/etc/mview.xsd">
    <view id="vendor_product_tag_view">
        <subscriptions>
            <table name="vendor_tag" entity_column="tag_id"/>
            <table name="vendor_tag_product" entity_column="tag_id"/>
        </subscriptions>
    </view>
</config>

Managing modes:

# Check indexer status
php bin/magento indexer:status

# Set to real-time
php bin/magento indexer:set-mode realtime vendor_product_tag

# Set to schedule
php bin/magento indexer:set-mode schedule vendor_product_tag

# Set to manual
php bin/magento indexer:set-mode manual vendor_product_tag

Reindexing:

# Reindex all
php bin/magento indexer:reindex

# Reindex specific
php bin/magento indexer:reindex vendor_product_tag

# Check if reindex needed
php bin/magento indexer:status

Debugging and managing indexers effectively.

Indexer status commands:

# Show all indexers and their status
php bin/magento indexer:status

# Show specific indexer info
php bin/magento indexer:info vendor_product_tag

# Show indexer dependencies
php bin/magento indexer:info

Common indexer issues:

# Index shows 'UPDATE REQUIRED'
php bin/magento indexer:reindex

# Indexer stuck
php bin/magento indexer:reindex vendor_product_tag

# Performance issues
php bin/magento indexer:set-mode schedule vendor_product_tag

Debugging indexer:

// Check if indexer is working
$indexer = $this->indexerFactory->create()->load('vendor_product_tag');
echo $indexer->getStatus(); // 'valid' or 'invalid'

// Force reindex
$indexer->reindexAll();

Indexer logs:

-- Check reindex history
SELECT * FROM indexer_state WHERE indexer_id = 'vendor_product_tag';

-- Check scheduled changes
SELECT * FROM mview_state WHERE view_id = 'vendor_product_tag_view';

Performance tips:

1. Use schedule mode for non-critical indexers
2. Batch reindex for large datasets
3. Monitor indexer status in production
4. Set up cron for automatic reindexing