Global Properties

> Your client can present any model that it wants, but to 
> interoperate with multiple servers, it needs to adhere to the 
> DeltaV semantics, in which the VCR and VHR are separate 
> resources with their own locks. Similarly, your client can do 
> whatever it wants in terms of displaying a global property 
> model, but to provide an interoperable form, it must use 
> DeltaV/WebDAV compatible requests (such as modeling global 
> properties as properties of the shared VHR).


'Modeling' global properties as properties of the VHR in such a system
is necessarily a proprietary design.  It is simpler to just say that
DeltaV does not provide global properties, period.

For properties to be global, I have to be able to get them by doing a
propfind on the VCR or any particular VERSION.  If I have to go to two
completely different places with two completely different requests, then
they are not behaving as global properties.  Pretending that they are
would only confuse people.

=====================

Global Properties are still useful, though.  But the only real way I can
see them being implemented is adding something like a scope attribute to
the prop element like:

<property-update>
  <prop scope=global>
     <globalprop1>foo</globalprop1>
  </prop>
</property-update>

============================

I assume that servers that don't support global properties would just
ignore the scope attribute.

Received on Wednesday, 12 September 2001 18:28:51 UTC