Media Gallery Indexing

Overview

Media gallery indexing is a process of reflecting media assets located in media storage in the database.

Media gallery data consistency is ensured by updating the information about media gallery assets on each media asset upload and delete operation.

The indexing is required only in the following two situations:

When Enhanced Media Gallery is enabled (to reflect already existing media assets in the database)
After manual changes are applied to media storage bypassing the Magento application

There are two stages of media gallery indexing process:

The indexing process includes the following steps

Stage 1

Scan the media assets storage
Retrieve the data for each media asset
Create and save media asset entities to the database. Write the data to media_gallery_asset table Stage 2
Retrieve information of media assets from the database
Retrieve information required for displaying in the media gallery grid from extensions
Update media_gallery_asset_grid with flat data for media gallery grid rendering

There are two triggers for the media gallery indexing process:

bin/magento media-gallery:index console command can be used for manual index triggering. The command is implemented by Magento\MediaGalleryUi\Console\Command\IndexAssets
Saving the stores configuration after enabling Enhanced Media Gallery implemented by Magento\MediaGalleryUi\Plugin\MediaGalleryIndexerTrigger::afterSave plugin applied to Magento\Framework\App\Config\Value class

Magento\MediaGalleryUi\Model\ImagesIndexer::execute provides the assets storage root path, assets name pattern, indexer options and list of asset indexers configured in the DI
Magento\MediaGalleryUi\Model\FilesIndexer::execute goes through the file system and calls Magento\MediaGalleryUi\Model\Filesystem\IndexerInterface for each file (\SplFileInfo)
Magento\MediaGalleryUi\Model\Filesystem\IndexerInterface is responsible for retrieving any information needed from \SplFileInfo and saving it to the database