MgdSchema dependent objects

1. Piotr Pokora

   MgdSchema dependent objects

   Thu January 08 2009 12:24:24 UTC
   Hi!
   
   Take a look at this ticket:
   http://trac.midgard-project.org/ticket/541
   
   First requirement is already fixed in Ragnaroek.
   The latter one makes me think about adding new MgdSchema methods.
   
   To make it internally in core, I need to create new core functions which
   check:
   
   * object has children
   * object has attachemnts
   * object has parameters
   
   What about adding such methods to public API?
   
   * bool has_children(void);
   
   Returns true if object has children objects.
   Basically this function will check every class children objects, even
   of the same type.
   And will return false if any of child class' object (in tree) exists.
   
   * bool has_attachments(void);
   
   Returns true if object has attachments. Blob existance check will not
   be done.
   
   * bool has_parameters(void);
   
   Returns true of object has parameters.
   
   Of course, base delete and purge methods will use all those methods
   internally to keep data safe.
   
   And the questions are:
   
   * Do we have use cases to provide such API on higher level?
   * Should we look for dependent objects during delete or purge? Or both?
   
   Piotras
   _______________________________________________
   dev mailing list
   dev@lists.midgard-project.org
   http://lists.midgard-project.org/mailman/listinfo/dev
   •  Reply
2. Henri Bergius

   Re: MgdSchema dependent objects

   Thu January 08 2009 12:28:39 UTC

   Hi,

   • Do we have use cases to provide such API on higher level?

   Yes, I think it would make life easier in places like replicator and Asgard navigation.

   • Should we look for dependent objects during delete or purge? Or both?

   I think so, yes.

   At least in Vinland trying to delete an object that has undeleted dependents should raise an exception. For Ragnaroek that is probably too big API change.

   /Henri

   •  Reply
3. Piotr Pokora

   Re: [midgard-dev] MgdSchema dependent objects

   Thu January 08 2009 12:34:23 UTC
   Henri Bergius writes:
   > Hi,
   >
   >> * Do we have use cases to provide such API on higher level?
   >
   > Yes, I think it would make life easier in places like replicator and Asgard navigation.
   
   OK. those methods should be optimized for perfromance, so could be
   faster then QB's count.
   And bindings implementation is trivial once we have those in core.
   
   >> * Should we look for dependent objects during delete or purge? Or both?
   >
   > I think so, yes.
   
   Yes both? Or only one of them? :)
   I was thinking that would be safe to ignore check during purge once
   object is marked as deleted.
   But on the other hand consistency is much more important than purge
   performance.
   
   > At least in Vinland trying to delete an object that has undeleted dependents should raise an exception. For Ragnaroek that is probably too big API change.
   
   Yes, this is only vinland thing. In Ragnaroek we can workaround it on
   PHP level if needed.
   
   Piotras
   _______________________________________________
   dev mailing list
   dev@lists.midgard-project.org
   http://lists.midgard-project.org/mailman/listinfo/dev
   •  Reply
4. Marcin Sołtysiak

   Re: [midgard-dev] MgdSchema dependent objects

   Thu January 08 2009 12:39:40 UTC
   On Thu, 08 Jan 2009 13:34:23 +0100, Piotr Pokora <piotrek.pokora@gmail.com>
   wrote:
   
   > But on the other hand consistency is much more important than purge
   > performance.
   
   +2
   
   Solt
   _______________________________________________
   dev mailing list
   dev@lists.midgard-project.org
   http://lists.midgard-project.org/mailman/listinfo/dev
   •  Reply