Re: Issue 133: SOAP and Web Architecture: Draft sentences for HTTP bi nding preamble.

----- Original Message -----
From: "Paul Prescod" <paulp@ActiveState.com>
To: "Williams, Stuart" <skw@hplb.hpl.hp.com>; <xml-dist-app@w3.org>
Sent: Monday, February 18, 2002 7:41 PM
Subject: Re: Issue 133: SOAP and Web Architecture: Draft sentences for HTTP
bi nding preamble.


<SNIP>
> "In HTTP, anything which does not have side-effects must use GET"
>
>  * http://www.w3.org/DesignIssues/Axioms.html#state
>
> Although Tim has agreed that this is stated a little bit too strongly
> the general approach is correct and the reasons for it are rock-solid
> and are the foundations of the Web. It is great that you allow multiple
> bindings but the default binding must respect the axioms of web
> architecture. A SOAP call that does a safe and idempotent information
> retrieval should use GET and express the thing that is being gotten
> through the URI. SOAP should have a built-in feature that allows this.
>
>  Paul Prescod
>

It is unclear ( to me at least ) how such a call would differ from a
standard HTTP GET. What would make it SOAP? Just the fact that the HTTP
response would contain an Envelope element? Or the fact that the
Content-Type header of that response would be application/xml+soap? Or both?
Also, given that the Envelope will *NOT* be used to serialize the request is
it really SOAP, given that the Envelope is a core part of the spec? Given
that the envelope is hierarchical ( it is an Infoset, after all ) I'm not
sure I can see a reasonable way to encode it into the query string (
although I can see how you might encode very simple requests into the URI ).

Also, it would seem *VERY* problematic to try and use SOAP Headers in such
an example, where are we supposed to put those in a GET? I understand that
idempotent HTTP requests should use GET. But it seems that some of the
things I might want to include in an idempotent SOAP request might include
SOAP headers. Are you suggesting we define a way to encode SOAP headers as
HTTP headers?

Or maybe the query string should just be ?xml='<soap:Envelope....' in which
case perhaps all these problems go away... Is that what you think we should
do?

Gudge

Received on Tuesday, 19 February 2002 07:22:49 UTC