[hibernate-dev] Hibernate OGM mapping for "server side Hibernate Search" via Infinispan Remote

[Fabio Massimo Ercoli]

Hi Sanne,

what you speak of in my opinion is a very very cool feature.
Moreover server-side indexes (and remote dialect) are more suitable for
Openshift applications.

Using standard javax.persistence.Index APIs could be a very nice
alternative to avoid confusion with Hibernate Search client side usage.
For the problem (B) maybe we can extend the API (adding a some non standard
annotation, at least one for the analyze).

I'm really interested in this development. Thank you.

Fabio


On Wed, Mar 14, 2018 at 12:52 PM, Sanne Grinovero <sanne at hibernate.org>
wrote:

> Hi all,
>
> this one is a very desirable feature, yet tricky as there's high
> chances of ambiguity and confusion for end users.
>
>
> # Infinispan Remote indexing
>
> Infinispan embeds the Hibernate Search engine, and uses it to index
> data being inserted in any cache having indexing enabled. As you know
> Infinispan can be used to store Java POJOs, which get serialized using
> JBoss Marshalling - or encoded into Protobuf entries using Infinispan
> Protostream as helper layer.
>
> Hibernate OGM supports both modes, one meant for "Infinispan Embedded"
> and one for "Infinispan Remote" as that's what each encoding strategy
> is suited for.
>
>
> # Protobuf & indexing
>
> Protobuf is a well defined format with plenty of documentation which
> focuses on a "schema" of the encoding; Hibernate OGM is able to
> generate such schemas dynamically and will generate encoders and
> decoders which follow the encoding guidelines for Java objects.
>
> The meta schema of protobuf is not super flexible, yet there's the
> option of annotating the Protobuf schema elements using "annotations"
> in comments.
> Protostream allows inserting Hibernate Search annotations directly in
> these comments and will use them to generate the server side indexing
> configuration, implicitly also allowing such properties to be queried
> using indexed.
>
> For example you might have this string literally within the comments:
>  "@Field(store = Store.YES, analyze = Analyze.YES)"
>
> A full example of schema can be found here [1].
> (The Infinispan documentation is a bit sparse on this as they
> encourage people to use another code gen tool, best refer to tests as
> examples when working for OGM)
>
>
> # What should OGM users experience?
>
> A naive solution would be to allow people to use the Hibernate Search
> annotations on their JPA entities, and we have OGM copy these into the
> generated schema; there's a number of problems with that:
>  - not all such annotations "translate" equally well [2]
>  - there's a mismatch between JPA properties and underlying encoding fields
>  - if I run a FullTextQuery do I expect it to work remotely?
>  - what if I want to use Hibernate Search locally as well or instead?
>  - references to local classes obviously won't work (custom
> fieldbridges, analyzers, etc..)
>
> An alternative is to look at these as "indexes" of the underlying
> store, so we'd use them to hint the Infinispan server about user
> provided hints such as those generated by `javax.persistence.Index`.
> I do think this is the cleaner approach, yet has two drawbacks:
>  A- I guess ORM might implicitly generate some indexes in its metadata
> which the user might not have explicitly asked; e.g. accelerate unique
> constraints and foreign keys; it's possible these might not be as
> useful as expected in the Infinispan case.
>  B- we won't be able to leverage the awesome full-text capabilities :-(
>
> I believe A is something we could ignore for now and revisit if
> there's actual demand.
>
> B is also not urgent, yet disappointing limitation as this capability
> is a distinguishing feature of this NoSQL. Would we agree that
> exposing such full-text capabilities would best be let to an ad-hoc
> backend in Hibernate Search 6?
>
>
> Thanks,
> Sanne
>
> 1 - http://blog.infinispan.org/2018/02/restful-queries-
> coming-to-infinispan-92.html
> 2 - https://github.com/infinispan/infinispan/blob/master/remote-
> query/remote-query-server/src/main/java/org/infinispan/
> query/remote/impl/indexing/IndexingMetadataCreator.java#L31
> _______________________________________________
> hibernate-dev mailing list
> hibernate-dev at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/hibernate-dev
>