[Nepomuk] Refactoring for Soprano 3
mh182 at gmx.net
Tue Oct 13 21:20:12 CEST 2009
On Tuesday 13 October 2009 16:57:58 Sebastian Trüg wrote:
> Soprano 2 IMHO has a nice design. Backend, Model, and FilterModel suited my
> needs very well and were nice to use. But now it slowly reaches its limits.
> With Virtuoso the introduction of transactions become very important. I
> tried to stack them on top of Model as you can see in the experimental
> branch but the resulting design is flawed and cannot be any different
> since we need to stay binary compatible for KDE.
> Thus, it is time for a redesign and also time for you to state your needs
> and ideas.
> Attached you find a preliminary design in the form of a crude UML diagram.
> It is based on the sesame2 idea of Respository vs. RespositoryConnection.
Is there a general overview (description) how sesame2 and the other backends
work in the overall concept of Nepomuk and Soprano?
Before I can give my 2 cents I needs to grasp the overall concept ... which
may take some weeks.
> A few words of explanation:
> - Model is split into two classes Repository and RepositoryConnection.
> Each RespositoryConnection represents its own transaction object, i.e.
> can perform multiple transactions.
If you say "perform multiple transactions" do you mean those transactions are
performed sequentially per connection? Or can they also be processed in
> - A Repository can create an arbitrary number of RespositoryConnection
> - Backend is now RepositoryFactoy (better name welcome). It is used to
> create StorageRepositories which replace StorageModel and have settings
> like storage dir and the like.
> - FilterRepository and FilterRepositoryConnection replace the current
Newbie question: on which objects are filter applied? The result of the query?
> A FilterRepository would need to create its own connections which carry
> as a member a parent connection created by the parent Repository.
> This is the basis I would like to start the discussion from.
> Another issue is inference which I would like to integrate deeper into
> Soprano. The straight forward design would be to add a flags parameter to
> method like query() and listStatements() which can for example be
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