[hibernate-dev] HSEARCH State to transfer

[Emmanuel Bernard]

On 3 août 2011, at 20:06, Sanne Grinovero wrote:

> 2011/8/3 Emmanuel Bernard <emmanuel at hibernate.org>:
>> Here is a first prototype of the serializable model and an almost complete converter between List<LuceneWork> and this model.
>> 
>> There is not test yet. It does compile but I don't know if it works.
> 
> (translation of the above:
> https://github.com/emmanuelbernard/hibernate-search/tree/745 )
> 
> I only had a brief scan through the code, so I might send more comments later;
> 
> 1) Remember all operations are implicitly scoped to a single index, so
> for example you don't need to make a difference between
> Optimize(classType) and OptimizeAll, they will do the same: optimize
> the index.

That's a good point. Is that your last word though? Will we want to limit messages passing through by regrouping several backends under one message?

> 
> 2) It would be great if you could avoid the "instanceof" :)
> (see also org.hibernate.search.backend.impl.WorkVisitor )

Hum, I have always found the visitor pattern difficult to understand, that's why I usually chose this imperative approach.

> 
> 3) I'm confused about what your intentions are about those
> Serializable wrappers. Wrapping objects in some container implementing
> SerializableFieldable is not going to make them serializable. I think
> I missed, or you didn't add yet, where the conversion to byte[]
> happens ?

The model represents the data we want to pass in.
I am now exploring how to serialize it with various libraries. It looks though that these libraries won't be able to support version based deserialization logic and reuse the model as it is. We will likely need some unstructured version of the model and a code similar to the Converter logic.

So far I'm looking at MessagePack without much success. Documentation is sparse and they don't seem to support reading the version before the rest of the message.

> 
> 4) OperationBck could be removed.

Thanks