Re: Some items for discussion

Rama, 

thanks for the comments, I have logged them below as issues 6-9 in our
issues list [1].

When you have multiple issues like that (barring a bunch of minor
editorial comment), it's better to try to separate them into multiple
emails so that the discussion on the mailing list is better structured.

Anybody replying to Rama's message please change the subject to the name
of the appropriate issue on our issues list, if available. 8-)

Best regards,

Jacek

[1] http://w3.org/2002/ws/sawsdl/issues/#open

On Mon, 2006-04-24 at 23:27 -0400, Rama Akkiraju wrote:
> Hi all,
> 
> I would like to bring up the following items to the team’s attention.
> 
> Item: Clarification of SchemaMapping concept
> I think we should clarify schemaMapping concept a bit more in the spec. It
> is currently a bit confused between data mapping and schema mapping (We
> felt that it needed more work even while working on WSDL-S). In SAWSDL we
> are concerned with adding semantic annotations for the (abstract)
> interfaces of Web services. The purpose of these annotations is to enable
> discovery and semantic matching - not invocation. There are many more
> things that need to happen before actual invocations can be made even if
> semantic similarity is established via discovery and semantic matching. For
> example, even if we match ‘UPC’ and ‘SKU’ as semantically similar concepts
> (because both are unique identifiers for items), a UPC code can’t pass off
> for an SKU during the invocation (may be the # of digits are different and
> may need some transformation function). But we shouldn’t confuse this
> transformation that needs to take place between two WSDL elements (in this
> case UPC element in one WSDL to SKU element in the other WSDL) with the
> semantic annotations of elements in WSDL. For instance, the semantic
> annotations for UPC and SKU could be ‘<someontology>#UniqueIdentifier’.
> Therefore, specifying things like concatenating the values of ‘first name’
> and ‘last name’ to map to an ontology concept called ‘<someont>#name’ via
> an XSLT transformation is too low level information for semantic
> annotations (XSLT is for transforming XML documents rather than schemas). I
> think RDF mappings would be more appropriate for representing
> schemaMapping. I understand that we don’t prescribe the language that users
> would like to use for specifying these schema mappings but the examples
> that we give in the spec should be consistent with the concepts and
> recommended best practices. I think we should revisit the examples for
> schema mapping and consider RDF mappings. Thoughts?
> 
> Item: Multiple annotations for operation
> An operation has a modelReference. If we are supporting multiple
> modelReferences on elements, we should apply the same logic for an
> operation and make sure that users can associate multiple modelReferences
> on an operation as well.
> 
> Item: Multiple annotations for a complex type
> A complex type currently can have both a modelReference and a
> schemaMapping. Also there is an implicit association between the
> modelReference and schemaMapping. For example, in the example in the spec
> <complexType name="POAddress"
>  wssem:schemaMapping
> ="http://lsdis.cs.uga.edu/projects/meteor-s/wsdl-s/examples/POAddress.xsl"
>  wssem:modelReference="POOntology#Address" >
> 
> there is an implicit association between the modelReference pointing to the
> ‘Address’ concept in the ontology POOntology and the schemaMapping concept
> that is pointing to the PoAddress.xsl – which is supposed to specify the
> mapping between elements in the complex type ‘POAddress’ and concepts in
> the ontology POOntology. If we want to support multiple annotations, say
> one for OWL and the other for WSML this association would be hard to keep
> track of. There are multiple ways to deal with this.
>    (a) just add multiple modelReferences and schemaMappings and let the
>       tools figure out the associations.
>    (b) use whatever mechanism we come up with to identify the type of a
>       model, we could use the same here and keep things consistent.
> 
> Item: Conflict Resolution Rules (at the bottom of the section 2 in the
> spec):
> At the bottom of the section 2, we specify a bunch of rules to resolve
> conflicts. Is there a way to formalize these rules or enforce them via the
> spec? Or may be we should think about designing things in such a way that
> conflicts don’t arise at all.
> 
> Editorial Comment:
> Why was the example at the beginning taken out? I usually find most specs
> very reader unfriendly. An example upfront is a great way to introduce the
> ideas. I strongly believe that we should have a full example at the
> beginning.
> 
> Item: Editorial Change
> Section 2.1 in the current version of the SAWSDL spec refers to ‘action’
> concept. It is actually a modelReference on the operation. So, references
> to ‘action’ should be taken out.
> 
> Item: Editorial Comment
> Should we cleanup the namespaces for examples referring to ibm and lsdis
> web sites to point to more neutral namespaces.
> 
> Regards
> Rama Akkiraju
> 

Received on Monday, 1 May 2006 16:07:55 UTC