Fw: [wsrf] Issue WSRF9

[Tim Banks <tim_banks@uk.ibm.com>]

Hi William,

I (like Bryan) have been wondering what use cases there are for the dynamic
use of properties alluded to by issue 9  and it was suggested to me that
WSDM may have some (and you are the link man with WSDM).   Perhaps the WSDM
group could give us some input?

Regards, Tim Banks
IBM TP Architecture & Technology. Hursley, UK.
Phone: External +44 1962 815639, Internal 245639
----- Forwarded by Tim Banks/UK/IBM on 21/06/2004 19:16 -----

"Murray, Bryan P." <bryan.murray@hp.com> wrote on 21/06/2004 18:07:15:

>    I understand the need to know which properties are currently
> present
>    in the property document given that the property document
> supports
>    dynamic properties. However, I would like to see a use-case
> describing
>    the need to retrieve at runtime the schema for any properties.
>
>    The only reason I can think of for retrieving properties which
> an
>    application does not already understand is if the application
> simply
>    displays properties to a human or copies the property somewhere.
> If
>    the application understands the namespace of the property it can
>
>    locate the type from the WSDL/schema for the namespace.
> Otherwise,
>    simple properties (no child XML elements) can be displayed
> without
>    understanding their type by just treating the text node as a
> string.
>    The application can choose to either not display complex
> properties or
>    to list attributes and child elements with their values.
> Grandchild
>    elements or attributes will ultimately make this too complicated
> to do
>    at some point.
>
>    Other, more complex, applications will need to understand not
> only the
>    syntax of the properties they are retrieving, but also the
> semantics
>    of those properties in order to interact with them
> appropriately. The
>    syntax can be found in WSDL/schema files, but the semantics
> needs to
>    be understood by the programmer writing the property retrieval
> code. I
>    am confused as to how an application could interact with a
> property it
>    does not understand beyond simply displaying or copying its
> value. If
>    an application does understand a property that falls into the
> xsd:any
>    portion of the resource property document schema, it does not
> need the
>    schema - it already knows the type of this property.
>
>    If there is no need beyond displaying or copying the value of an
>
>    unknown property I suggest that we not provide the ability to
> retrieve
>    the schema at runtime.
>
>    Can someone offer a use-case that shows where my thinking is
>    deficient?
>
>    Bryan
>