- From: Tim Ewald <tjewald@develop.com>
- Date: Fri, 8 Feb 2002 21:33:05 -0500
- To: "'XMLDISTAPP'" <xml-dist-app@w3.org>
> Now, I can understand the case for dropping the graph model entirely; To be frank, this is where I want to go and I should just admit it. :-) I *strongly* believe that we should focus on what XML's native model, i.e., trees, and work out from there. I'm very much afraid that we are headed down a path where people will be forced to choose between SOAP's graph-oriented data model and the tree-based world of XML. I agree that providing schema(s) for representing a graph as a tree is not optimal because of all the possible permutations. However, it is possible to define a schema for the results of applying a particular encoding. I'd *rather* just use XSD and work with trees, because that's what all of the XML tools and technologies are designed to support. But if I have to accept an alternative like the SOAP data model, I want a way to get back to trees, even if I need a different, ugly schema for each encoding scheme (and this is basically what the SOAP encoding rules do anyway). I'd really prefer that we stay away from a language for describing graphs in terms of structs, arrays, etc. In XML, we have a viable cross-vendor/language/platform way to represent and manipulate typed data, with a tremendous amount of tool support. All of that is based on trees. While trees certainly have limitations, I don't want to see us go back to the beginning and start over with a language for graphs! I would love to see SOAP 1.2 back off from graphs and encodings altogether. I'd love to see SOAP message formats defined entirely in terms of XSD, ensuring compatibility with all the other XML technologies and tools. If that means that I can't transparently map arbitrary object models to SOAP messages, I'm fine with that. To me, tight integration with the rest of XML is more important. I also think it is what will happen anyway. The vast majority of the people I talk to about SOAP believe that "document/literal" is the way to go precisely because it is based on XSD. Of course, defining contracts in terms of tree-based messages makes dealing with graphs harder. However, in many cases this is not an issue and, in the cases where it is an issue, graphs can be mapped to trees in a range of ways. For me it is simple: if we are building on XML, we are building on trees. I would rather be able to work directly with SOAP *and* XSD and all the other XML technologies and push the issue of representing graphs up to the application level then define SOAP in terms of graphs and force people to adopt a new data model that XML doesn't natively support. I really believe that this change is actually critical to SOAP's future success. I also believe that a lot of people - starting with me - are going to work at the XSD level no matter what the SOAP RPC model says. So, the question is: how many people would support the shift away form graphs to XSD? Thanks, Tim- > > ------------------------------------------------------------------ > Noah Mendelsohn Voice: 1-617-693-4036 > IBM Corporation Fax: 1-617-693-8676 > One Rogers Street > Cambridge, MA 02142 > ------------------------------------------------------------------ > > > >
Received on Friday, 8 February 2002 21:34:24 UTC