Re: Use cases for XML serialization

Bijan Parsia wrote:
> For Howard(?), I restate (I hope concisely) some use cases for XML 
> Serialization:
> 1) I think for a good WSDL for SPARQL, having an XML Schema type for 
> specifying the input and output messages in the abstract interface is 
> highly desirable. This generates, as a side effect, and XML 
> serialization.
> 2) I think for actual bodies of SOAP messages, XML is preferable. I 
> guess, in general, embedding XML in XML formats is better than 
> embedding strings in other formats. Especially if validatable.

Agreed - with the caveat that this is the long term goal and is not a prequistie 
for SPARQL version 1.

(This is very true for query services such as query brokering - which was one 
example of service composition given.  We can declare vistory for SPARQL v1 
without having solved the query brokering and federation dimension.)

> 3) I was already generating a XML format in order to support legacy 
> applications with say, RDQL, Versa, and SeRQL services. I prefer 
> generating XML from a SPARQL query, and using XSLT or XQuery to 
> generate RDQL or other query languages.

Doesn't that put a another requirement on the SPARQL.xml syntax?  It now needs 
to work with RDQL, Versa, and SeRQL as well.

> 4) Having schema (which entails XML serialization) allows us to express 
> what parts of the query language a server does or does not support for 
> various datasets (or all of them). So I can, I believe, restrict the 
> query to only allow select queries if I don't support ask, describe, or 
> construct *without* the working group having to define any conformance 
> levels.

This one suprised me.  I would expect the service description to include this 
information but also features that are not syntactic, like extension functions 
support, or vocabularies used in datasets.  In other words,I expected one 
framework for this and, as it is not all syntactic, I was expecting it not to be 
tied to any syntax.


> There are others, but I hope this is a good start. (Am I trying to 
> convince people, or trying to generate something for the use case 
> document?)

I found it helpful - thanks.


> Cheers,
> Bijan.

Received on Wednesday, 23 March 2005 10:03:32 UTC