Re: Few questions about REST

Hello Mark,

> > So when you said that "doc-lit SOAP is RESTful" what did you mean by
that ?
>
> Did I say that? <snip/>
Yes you did :-). And it's now in www-archive :-)

> I think I may have said that the RESTful use of SOAP looks like doc/lit,
> but where there's no method in the body.  i.e. where the document is just
> state.
And I'm just trying to see how RESTful a doc-lit SOAP *can* be.
It seems you do agree that a doc-lit SOAP can meet a resource identification
constraint.
Doc-lit SOAP can also meet a uniform interface constraint, that is all
identified resources support the same uniform interface, at least POST and
GET.
The only question to me is it a uniform interface constraint which is not
met completely when POST is used instead of GET (the same as it can be used
instead of PUT and DELETE), I think it's a uniform interface one, and this
is what I meant when saying that doc-lit SOAP doesn't meet the constraint
strictly. Or is it some other, perhaps a derived constraint, which is not
met in such a case ?

Doc-Lit SOAP can also meet other REST constraints.
So, can we say that a doc-lit SOAP is "mostly" RESTful, taking into account
that it can meet all constraints ?

Cheers
Sergey Beryozkin

----- Original Message -----
From: "Mark Baker" <distobj@acm.org>
To: "Sergey Beryozkin" <sberyozkin@zandar.com>
Cc: <www-archive@w3.org>
Sent: Tuesday, September 16, 2003 4:06 AM
Subject: Re: Few questions about REST


> On Mon, Sep 15, 2003 at 01:15:35PM -0400, Sergey Beryozkin wrote:
> > > > Can we consider doc-lit SOAP as being "mostly RESTful" ?
> > >
> > > In general, I don't think so.  Resource identification and the uniform
> > > interface are absolutely core to REST.  If the interface were "very
> > > general", without being strictly "uniform" (e.g. "PROPFIND", or
> > > "SEARCH"), but resources were identified, then I would answer "yes".
> >
> > For example, the same way as PROPFIND would be used to retrieve a
property
> > of some identified resource and possibly create it if it's not
available,
> > setting it to some initial value passed in a request's body ? In other
> > words, using PROPFIND would not be trictly "iniform" in that it'd be
used
> > for not only retrieving a property, the same way as doc-lit SOAP
sometimes
> > uses POST for retrieving the representation.
>
> No, PROPFIND isn't strictly uniform because it doesn't make sense for all
> objects; it only makes sense on properties.
>
> Think of REST's "uniform interface", as the interface that would be
> exposed by the root object in a hierarchy, such as java.lang.Object.
> You wouldn't put getStockQuote() on it, right?
>
> > > But if we're talking about very specific methods like "getInvoice",
> > > then I'd have to answer "No".
> > Do you refer to the fact that a doc-lit SOAP, while not passing method
> > names, can still be used to "getInvoice" with a message body being empty
and
> > SOAPAction hinting to a handler that a  getInvoice() should be invoked ?
>
> No, just what I said above.
>
> > I thought you agreed in an earlier message that if a control parameter
> > (SOAPAction or application/xml+soap action attribute) is a URI then it's
> > semantically equivalent to a case when such a control parameter is
passed
> > within a resource URI. A resource then could still be identifiable. For
> > example, 1 is a (relative) URI to a subordinate resource :
> >
> > POST mainResource/1
> >
> > and
> >
> > POST mainResource
> > application/xml+soap; action=1
> >
> > seem to be equivalent, especially due to the fact that
> > "application/xml+soap" is a registered mime type and it might be easier
for
> > generic intermediaries to understand that it's  mainResource/1 which is
> > identified.
> > Do you agree ?
>
> Yes.  When the out-of-band information (e.g. "action=1") is
> *identifying* information, then we're in synch.  It's when the out of
> band information defines the interface semantics that things go wrong,
> because it messes with the contract.  For example, a successful response
> now means something different; the success refers to the action, rather
> than to the simple submission of data for processing.
>
> > So when you said that "doc-lit SOAP is RESTful" what did you mean by
that ?
>
> Did I say that?  It *can* be, but 99.99% of people still put a method
> in the body.  By definition, that's unRESTful.
>
> I think I may have said that the RESTful use of SOAP looks like doc/lit,
> but where there's no method in the body.  i.e. where the document is just
> state.
>
> > I'll try to understand better what you said with respect to
late-binding,
> > and then I'll ask more questions :-)
>
> Fire away!
>
> Mark.
> --
> Mark Baker.   Ottawa, Ontario, CANADA.        http://www.markbaker.ca
>
>

Received on Wednesday, 17 September 2003 07:32:26 UTC