Re: Filters as views (ISSUE-45)

Hi Ruben

>My hunch is that any definition of a view
>will always be such that, implicitly or explicitly,
>a view is a collection (because all the views I've seen
>so far, are indeed a set of things with common properties,
>or in other words: a collection). So please prove me wrong,
>as this will get us closer to an understanding of what a view is.

Consider this:
GET /people/karol?select=name,surname

Assuming that the 'select' is an equivalent of an SPARQL/SQL SELECT clause
(which is not in hydra yet), client would expected the server to return
</people/karol> truncated only to two properties/statements (name and
surname).
Resource </people/karol> is not a collection, thus the result of this
request would be a view of the original resource. Request for /people/karol
would end up with whole resource description.

To think of it, it would be possible to page this resource as well as there
is always a level of abstraction that allows partitioning (bytes,
statements, etc.)

Unless we're treating each resource as a collection of triples (or
properties in case of plain old JSON objects), there are views that are not
collections.

We could go event further:
GET /people/karol?select=concat(name, ' ', surname)

While it goes to an area on which I'm not keen to define these kind of
weird constructs in the code Hydra, but these kind of transformations will
produce a view in my opinion

Regards

Karol


2016-01-15 10:29 GMT+01:00 Ruben Verborgh <ruben.verborgh@ugent.be>:

> Dear Tomasz,
>
> >> Curious to see the definition that describes
> >> exactly what separates a view from a collection :-)
> >> (That's what I'm after in this whole thread.)
> >
> > please tell me why are we mostly confined to collections in this
> discussion?
>
> We're not: as you can see above,
> I want to know how exactly a view _differs_ from a collection,
> such that we can proceed to think about views in their own right.
>
> I'm not trying to hijack the discussion;
> rather, I want to force us to clearly define a view,
> as this has not happened so far at the moment.
>
> My hunch is that any definition of a view
> will always be such that, implicitly or explicitly,
> a view is a collection (because all the views I've seen
> so far, are indeed a set of things with common properties,
> or in other words: a collection). So please prove me wrong,
> as this will get us closer to an understanding of what a view is.
>
> > The server could advertise a view, which filters by those properties'
> labels.
>
> > In my eyes a view should be defined as derived from any resource,
> collection or otherwise.
>
> As far as I understand, views so far were seen as
> views on a collection, hence hydra:PartialCollectionView.
>
> Best,
>
> Ruben
>