7.x Index management compatibility with ES 8.x

[rudolf]

Index management uses the deprecated include_type_name parameter in a couple of places:

https://github.com/elastic/kibana/blob/7.17/x-pack/plugins/index_management/server/routes/api/mapping/register_mapping_route.ts#L33
https://github.com/elastic/kibana/blob/7.17/x-pack/plugins/index_management/server/routes/api/templates/register_get_routes.ts#L30
https://github.com/elastic/kibana/blob/7.17/x-pack/plugins/upgrade_assistant/server/lib/reindexing/reindex_actions.ts#L223

I didn't test the code, but it's possible that these API calls would fail if Kibana is connected to Elasticsearch 8.x

Related to #122459

[elasticmachine]

Pinging @elastic/platform-deployment-management (Team:Deployment Management)

[cjcenizal]

I'd consider this a bug but not a blocker, because the user can still use Console to access the underlying ES APIs and perform operations on indices and index templates. So we can ship a fix in a 7.17.patch release. See #122459 (comment) for a reference to how folks are solving this problem elsewhere.

[sebelga]

I am not sure I follow on this. Why is this a bug? We are using a 7.x API in 7.17. We need to use it (and set it to true) because ES still support mappings type in 7.x. and the UI must too.

https://www.elastic.co/guide/en/elasticsearch/reference/current/removal-of-types.html

[cjcenizal]

@sebelga The related issue #122459 has more context, but the summary is that during the upgrade process to 8, some or all ES nodes will be on 8.x while Kibana is still on 7.last. We want Kibana to continue to function in this situation. So we need to ensure any requests from Kibana 7.last won't fail if ES is on 8.x.

[sebelga]

Thanks @cjcenizal. I haven't been part of the decision process on this but it does seem that supporting this scenario is adding a lot of potential headaches and I am not sure I see the benefit (but again maybe I am missing something).
So our goal is to support a fully functional 7.17 Kibana against an 8.0 Elasticsearch?

From what we have been doing in the stack management team during the 7.x cycle this was never contemplated.

[cjcenizal]

So our goal is to support a fully functional 7.17 Kibana against an 8.0 Elasticsearch?

@sebelga Right. This is a very late-breaking requirement.

[cjcenizal]

Let's pause any work on this until we've made a Kibana-wide decision on how to address these types of bugs.

[cjcenizal]

I'm going to close this since it seems unlikely we'll be able to act on it and it seems like a corner case. Let's reopen it if it comes up as a real problem.