Re: Static vs. dynamic aspects of a service description (was Re: HTTP properties

On May 4, 2004, at 12:03 PM, Mark Baker wrote:
> I wonder if an extension couldn't be defined to allow a WSDL document
> to declare whether what its asserting is intended to be true for all
> time, versus just true at this moment in time, at a very fine level of
> granularity (per feature)?  That would permit code generators to ignore
> the "at this moment in time" assertions, thereby preventing them from
> generating code which could break when that thing changes.

I wonder at how useful that would be; predicting the stability of 
metadata (or entire representations, for that matter) is a tricky 
business.

It would be more useful to see such descriptions as hints; i.e., the 
dynamic negotiation mechanisms still need to be honoured, but the 
static hints allow you to make informed decisions before you get the 
feedback (e.g., the error message that says "I don't support 
compression in requests").

I do agree that there's an issue regarding description and metadata 
lifecycles, but don't think they're specific to this particular aspect.

This also highlights some areas of HTTP that are lacking, in terms of 
error reporting; e.g., AFAIK there's no machine-readable way to say "I 
don't support compressed requests". I'd much rather define these in a 
HTTP-specific way than in a SOAP-specific way; perhaps the HTTP 
errata-in-progress is a place to introduce such a mechanism.

Cheers,

--
Mark Nottingham   Principal Technologist
Office of the CTO   BEA Systems

Received on Thursday, 6 May 2004 14:04:40 UTC