[hibernate-dev] [HSEARCH] Feedback on Elasticsearch presentation

[Emmanuel Bernard]

Hey all,

I've done a presentation of the new Elasticsearch integration with a
Elasticsearch developer+advocate. Here are some key inputs from the
listener feedback.

The presentation was a Tools in Action (30 mins) where we took a JPA
app, added Elasticsearch for entity indexing manually (describing
issues) and then restart with Hibernate Search.

There was big interest, so a bit less feature release earlier will help
more than "better" later.

One big feedback is that we need to help people on the analyzer
definition in Elasticsearch (from our metadata):

- map existing ES analyzers to ours
- offer way to define an analyzer and have it pushed with the index
  definition when we create them
- figure out a way to embed the additional key options like nbr of
  shards when we create the index definition
- offer an export function for our index definition so that people can
  curl it themselves

The other part was about mapping:

- support for parent child: parent / child is a bit like Infinispan
  grouping where the children are colocated in the same node as the
  parent. So it's a single node join. David was not necessarily
  recommending me to support that from the get go because we already
  handle the right denormalization via HSearch.
- support for nested mapping and nested queries. This is also a
  relatively expensive prop so not all nested structure should be mapped
  as ES nested. Here we probably should offer a specific mapping
  annotation or option and write the nested query accordingly

For the mapping part, we probably should write these down in the FAQ as
to why we don't do them right away and the workaround available.

Emmanuel