Index Categories in a separate index

[real34]

As of ElasticSearch 6.0, it is not recommended/possible to have heterogeneous document types in the same index.

That is why ElasticSuite is now storing documents in different indexes (see https://github.com/Smile-SA/elasticsuite/blob/41c11b7648455deed8034b09cf3c10b3b2529eb8/src/module-elasticsuite-catalog/Model/Category/Indexer/Fulltext.php#L80).

We have decided to only index Products as a quick workaround to this change (see ec65c9d), and this issue is about reimplementing support for Categories indexation in a different index.

It is similar to #8 and already has mappings/logic implemented (

magento1-elasticsuite-indexer/src/app/code/community/Smile/ElasticSearch/Model/Resource/Engine/Elasticsearch/Mapping/Category.php

Line 54 in c54cf40

protected function _getSearchableEntities($storeId, $ids = null, $lastId = 0)

).

It would also be good to think (while doing #7?) about index management flexibility to improve this over time and support more use cases.

Notes

Do not forget to reimplement partial reindexing removed in d5bf5d4 and observers from \Smile_ElasticSearch_Model_Observer

References

• https://www.elastic.co/guide/en/elasticsearch/reference/6.0/breaking-changes-6.0.html
• https://www.elastic.co/blog/index-type-parent-child-join-now-future-in-elasticsearch