W3C home > Mailing lists > Public > xml-dist-app@w3.org > December 2001

RE: Possible new issue on interpretation of relative URI actors

From: Henrik Frystyk Nielsen <henrikn@microsoft.com>
Date: Tue, 4 Dec 2001 12:37:33 -0800
Message-ID: <79107D208BA38C45A4E45F62673A434D05A83F5C@red-msg-07.redmond.corp.microsoft.com>
To: <noah_mendelsohn@us.ibm.com>
Cc: <Noah_Mendelsohn@lotus.com>, <xml-dist-app@w3.org>

I agree - and a note would be good to that effect!

Thank you,

Henrik Frystyk Nielsen
mailto:henrikn@microsoft.com

>-----Original Message-----
>From: noah_mendelsohn@us.ibm.com [mailto:noah_mendelsohn@us.ibm.com] 
>Sent: Tuesday, December 04, 2001 12:19
>To: Henrik Frystyk Nielsen
>Cc: Noah_Mendelsohn@lotus.com; xml-dist-app@w3.org
>Subject: RE: Possible new issue on interpretation of relative 
>URI actors
>
>
>No problem.  Although we use slightly different words, I think 
>we are in 
>general agreement.  URI's reference resources, by definition.  I am OK 
>with drawing the conclusion that any node that acts in role #A 
>must (or 
>should, if you prefer) act in some corresponding absolute URI role as 
>well.  A consequence of this decision is, for a given absolute AbsU, a 
>node acting in #A and #B must act as either both AbsU#A and AbsU#B or 
>neither.  I think we should call that out with at least a note.
>
>---------------------------------------------------------------
>---------
>Noah Mendelsohn                                    Voice: 
>1-617-693-4036
>Lotus Development Corp.                            Fax: 1-617-693-8676
>One Rogers Street
>Cambridge, MA 02142
>---------------------------------------------------------------
>---------
>
>
>
>
>
>
>
>"Henrik Frystyk Nielsen" <henrikn@microsoft.com>
>12/04/2001 01:05 PM
>
> 
>        To:     <noah_mendelsohn@us.ibm.com>
>        cc:     <Noah_Mendelsohn@lotus.com>, <xml-dist-app@w3.org>
>        Subject:        RE: Possible new issue on 
>interpretation of relative URI actors
>
>
>
>I apologize if my mail seemed a bit sharp in the language - I 
>should have eaten something first.
>
>Henrik
>
>>-----Original Message-----
>>From: Henrik Frystyk Nielsen
>>Sent: Tuesday, December 04, 2001 09:12
>>To: 'noah_mendelsohn@us.ibm.com'
>>Cc: 'Noah_Mendelsohn@lotus.com'; 'xml-dist-app@w3.org'
>>Subject: RE: Possible new issue on interpretation of relative 
>>URI actors
>>
>>
>>
>>In SOAP, all we use URIs for is as identifiers. A role is
>>identified by a URI which by definition identifies a resource. 
>>We say nothing about what the semantics or properties of that 
>>resource and I think this is very important that we don't do.
>>
>>When you pick a specific URI scheme (like for example HTTP),
>>you explicitly pick a URI space with certain naming 
>>properties: whether it is hierarchical, whether it is 
>>case-sensitive, etc. etc. 
>>
>>One might know a suggested mechanism for dereferencing a URI
>>with a specific URI scheme may and if so then there is nothing 
>>that prevents anybody from ever dereferencing a URI but that 
>>is entirely outside the scope of SOAP.
>>
>>Dereferencing URIs is all about trust - I may trust DNS in
>>order to do so or I may trust somebody else to dereference it. 
>>As such I don't agree that URI semantics is dangerous in 
>>either of the cases you mention: it is a question of how I 
>>establish trust in determining whether a Node can act in the 
>>role that it claims it can.
>>
>>Henrik Frystyk Nielsen
>>mailto:henrikn@microsoft.com
>>
>>>-----Original Message-----
>>>From: noah_mendelsohn@us.ibm.com [mailto:noah_mendelsohn@us.ibm.com]
>>>Sent: Tuesday, December 04, 2001 08:07
>>>To: Henrik Frystyk Nielsen
>>>Cc: Noah_Mendelsohn@lotus.com; xml-dist-app@w3.org
>>>Subject: RE: Possible new issue on interpretation of relative
>>>URI actors
>>>
>>>
>>>The question is not so much about establishing a base, it is about 
>>>clarifying the responsibilities of a node in assuming a role.
>>>
>>>We have said nothing to indicate that a role is a web resource, or 
>>>that it is the resource named by the actor URI.  For example, we do
>>nothing to
>>>preclude naming a role as the name of some other resource.  Remember,
>>>there may be a large number of intermediaries, possibly in different 
>>>organizations that might want to assume a role like:
>>>
>>>        http://example.org/cachemanagers
>>>
>>>Any resource referenced by the URI is not general at any of the 
>>>intermediaries assuming the role, and it's almost surely not one 
>>>accessed via http or that follows the rules for the HTTP scheme.  In
>>>that respect, 
>>>one could argue that following the other rules for resources 
>>>is dangerous 
>>>as much as helpful. 
>>>
>>>On the other hand, you might make the case that this is 
>talking about 
>>>some other resource, but that the assumed role itself is not the
>>>resource.  In 
>>>other words, there's at least in principle a resource, 
>>>probably at some 
>>>nth+1st location, and the actor attribute is referring to that
>>>resource.
>>>In that case, I can see why we should follow the usual URI rules.  I 
>>>think that's about where you and I would find common ground.
>>>
>>>In any case, I see it as subtle enough that we should indeed say 
>>>something brief and clear about what's intended.  In other words, to 
>>>say that roles
>>>are indeed web resources (from which follows everything I 
>>>think you want 
>>>wrt/ naming).  I'm OK with that.
>>>
>>>---------------------------------------------------------------
>>>---------
>>>Noah Mendelsohn                                    Voice: 
>>>1-617-693-4036
>>>Lotus Development Corp.                            Fax: 
>1-617-693-8676
>>>One Rogers Street
>>>Cambridge, MA 02142
>>>---------------------------------------------------------------
>>>---------
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>"Henrik Frystyk Nielsen" <henrikn@microsoft.com>
>>>12/04/01 10:54 AM
>>>
>>> 
>>>        To:     <Noah_Mendelsohn@lotus.com>, <xml-dist-app@w3.org>
>>>        cc: 
>>>        Subject:        RE: Possible new issue on 
>>>interpretation of relative URI actors
>>>
>>>
>>>Please have a look at the proposed text for handling xml base which 
>>>already discusses the question of how to establish a base URI for a 
>>>message and how to deal with URIs in general. Given that we already 
>>>have an issue for xml base I am wondering whether we need another 
>>>issue.
>>>
>>>Henrik Frystyk Nielsen
>>>mailto:henrikn@microsoft.com
>>>
>>>[1] 
>http://lists.w3.org/Archives/Public/xml-dist-app/2001Dec/0005.h
tml
>>
>>>In private discussion, Henrik and I tripped over the question of a
>>>relative URI used as an actor.  If a block has:
>>>
>>>        Actor="#A"
>>>
>>>or
>>>
>>>        Actor="A"
>>>
>>>and if a node decides to act in that role, is there necessarily some
>>>other absolute URI in which role it needs to act?  I had assumed
>>"no", but I
>>>think Henrik had assumed "yes", and he further believes that no 
>>>changes to the SOAP spec are needed, as this is implicit in the web 
>>>and URI architecture and the definition of a relative URI.
>>>
>>>I would prefer to at least be a bit clearer in the spec, say a bit
>>>more about what the base URI for a message might be, etc.
>>>Presumably the base 
>>>URI must be stable through message processing, so if you no 
>>>how to make #A 
>>>absolute, then #B must follow from that and be handled consistently?
>>>
>>>All of this bears some relation to the dreaded Namespace
>issue (is it
>>>a string or a real URI) but at least in this case nobody is
>>proposing to
>>>actually retrieve a resource in most cases.
>>>
>>>Anyway, I recommend we open an issue.  Thanks.
>>
>>
>>
>>
>
Received on Tuesday, 4 December 2001 16:00:13 UTC

This archive was generated by hypermail 2.3.1 : Wednesday, 5 February 2014 22:28:13 UTC