[hibernate-dev] Decoupling indexed types from their class definitions

[Sanne Grinovero]

Hi  Gunnar,
yes we've been reviewing the Infinispan Query code and it seem that
what we have today if good enough for this release cycle.
We're keeping the issues open as the current approach can use some
polish, but time-wise we need to make space for more experimentation.

Sanne

On 7 October 2013 09:20, Gunnar Morling <gunnar at hibernate.org> wrote:
> Sanne,
>
> Is there any news on where we stand with this?
>
> I saw you discussed and moved some issues to HSEARCH 5; Does that mean we
> have everything in place now for the ISPN use case? I'd have assumed at
> least making the OBJECT_CLASS (HSEARCH-1402) field user-writable would be
> needed for restricting queries to specific "user types", but this one has
> been moved to 5 as well.
>
> Thanks,
>
> --Gunnar
>
>
>
> 2013/9/20 Gunnar Morling <gunnar at hibernate.org>
>>
>> Hi,
>>
>> I'm beginning to wonder which of these things we actually do need in 4.4
>> to satisfy the requirements of ISPN remote queries. At the moment we have:
>>
>> * the ability to index "user types" via one generic "value holder type"
>> using a smart class bridge which adds all the required fields; with
>> HSEARCH-1396 [1] we allow for passing bridge _instances_ to the engine which
>> e.g. enables to inject the user type configuration (which fields required)
>> into this class bridge by the client
>>
>> * the ability to query the properties of a user type by allowing to
>> specify the bridges to be used for given fields (HSEARCH-1409 [2], PR is
>> opened [3]); In particular this allows to query against fields which are not
>> statically declared for the value holder type
>>
>> >  the trouble is to filter on the correct user type where the Hibernate
>> > Search APIs expect - as basic filtering strategy - a java Class instance, or
>> > simply to have the flexibility to configure separate backends for each user
>> > type.
>>
>> I think this part is still missing. I'm wondering though whether it
>> couldn't be emulated "well enough" by making the
>> ProjectionConstants.OBJECT_CLASS field user-writable (as suggested with
>> HSEARCH-1402) and querying on this field? Together with the dynamic sharding
>> work from Hardy also the "separate backends for each user type" part might
>> be addressed by assigning each user type to a separate shard of the value
>> holder type's index.
>>
>> If this is feasible, it would allow to stick to the class-based design for
>> the time being. This might help with limiting the number of changes required
>> to be delivered with 4.4 and focus on implementing the dynamic entity
>> feature properly in HSearch 5. Any thoughts?
>>
>> --Gunnar
>>
>> [1] https://hibernate.atlassian.net/browse/HSEARCH-1396
>> [2] https://hibernate.atlassian.net/browse/HSEARCH-1409
>> [3] https://github.com/hibernate/hibernate-search/pull/486
>>
>>
>> 2013/9/11 Sanne Grinovero <sanne at hibernate.org>
>>>
>>> Some other projects use Hibernate Search - specifically the engine
>>> module - to bridge their domain model to a Lucene index and take
>>> advantage of its high performance low-level integration with Lucene.
>>> This is generally achieved by indexing a "valueholder" object which
>>> has most logic to create a custom o.a.l.Document in a top level
>>> @ClassBridge, or by using some custom FieldBridges, but has some
>>> strong limitations and feels more like a hack.
>>>
>>> In Hibernate Search 5.0 we will make this more flexible, so to move
>>> away from an annotated-entities index engine only to make it easier to
>>> index objects whose "schema" is more flexible than the contraints
>>> imposed by the staticness of a compiled Java class.
>>>
>>> We've discussed however to introduce some of these features right now
>>> (in version 4.4), so that we can start exploring the direction
>>> gradually and get some early feedback. In particular what seems to be
>>> troublesome is to implement multiple "user types" using the same type
>>> (java type) as valueholders: the trouble is to filter on the correct
>>> user type where the Hibernate Search APIs expect - as basic filtering
>>> strategy - a java Class instance, or simply to have the flexibility to
>>> configure separate backends for each user type.
>>>
>>> So this first refactoring [HSEARCH-1402] will be about moving the
>>> *internal* contract - without changing public APIs - to use a
>>> different identification than the current Class when we lookup for
>>> indexing information for a specific indexed type.
>>>
>>> Comments very welcome.
>>>
>>> Sanne
>>>
>>> - https://hibernate.atlassian.net/browse/HSEARCH-1379 Explicit support
>>> for indexing free-form (dynamic) entities
>>>
>>> - https://hibernate.atlassian.net/browse/HSEARCH-1402 Allow explicit
>>> user control of ProjectionConstants.OBJECT_CLASS value during indexing
>>>
>>> - https://hibernate.atlassian.net/browse/HSEARCH-1404 More flexibility
>>> than just Class to identify indexing metadata
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>>> hibernate-dev mailing list
>>> hibernate-dev at lists.jboss.org
>>> https://lists.jboss.org/mailman/listinfo/hibernate-dev
>>
>>
>