RE: Binding

> -----Original Message-----
> From: Mark Baker [mailto:distobj@acm.org]
> Sent: Tuesday, January 07, 2003 8:50 PM
> To: Miles Sabin
> Cc: www-ws-arch@w3.org
> Subject: Re: Binding
> 
> 
> Yes, but - and I admit I've done a poor job at explaining this - the
> "a priori" information we're talking about here for the 
> RESTful approach
> is just the same a priori information needed to understand a schema.
> There's nothing else that is needed - check above.  With 
> WSDL, you need
> the a priori information of how to process the schemas in use 
> *and* the
> a priori information of the interface to that data.
> 
> Do we agree to that last point, even if we may not agree on the impact
> to the properties of the respective architectural styles?


Well, sorta.  I see your point anyway.  The a priori information on how to
access the specific service is encoded in the URI in REST, and in WSDL for
the conventional web services approach.  URIs are a bit easier to paint on
the side of a bus (although realistically the URI to do anything interesting
with a Web service will be long and ugly) than WSDL documents are, but WSDL
documents are non-opaque, contain more information, and have all sorts of
programmer-friendly tools that work with them in conjunction with XML
schemas, Java classes, etc.  URIs leverage the Web more fully, WSDL
leverages XML more fully.   Also, we're only (AFAIK) talking about read-only
Web services here; more elaborate a priori information on the format of the
data to PUT or POST will be needed in either approach.  WSDL provides a way
to do that, it's unspecified (at present) in REST.

I think this distinction between alternative ways of encoding and exchanging
the a priori information needed to invoke a web service, and the tradeoffs
it engenders, is definitely worth noting in the WSA document.  Thanks, I
think we're actually getting somewhere today.

Received on Tuesday, 7 January 2003 21:13:32 UTC