Mark,
My point is that the WS-Addressing spec mandates that an absent
reply-to causes the receiver to infer an anonymous response:
Section 3.4 of the latest draft:
My understanding of this note, and of section 3.2, is that this
inference MUST be drawn by a receiver, irrespective of any extension
property like wsc:Response. Hence my proposal that we explicitly set
wsa:ReplyTo to "none".
Alastair
Mark Little wrote:
The
discussion during the f2f concluded that we are indeed using
wsa:ReplyTo in a way that, although probably legal, is not the way it
was meant to be used and can lead to confusion (as we've seen here). So
the first step in the process of removing that confusion, is to remove
wsa:ReplyTo, which was my proposal. What we replace it with, and what
the rules are around it, are the central points of the issue.
Alastair Green wrote:
Mark,
Taking off from a comment in the last paragraph of my written
contribution on this area during the F2F
http://www.oasis-open.org/apps/org/workgroup/ws-tx/email/archives/200603/msg00088.html
I think we need to address, in resolving this issue, the question of
the [reply endpoint] value being defaulted to anonymous.
The issue is about replacing wsa:ReplyTo in the case of "one ways that
may ultimately have a response but aren't really request-response based
messages" (to paraphrase). So in that case, we would be defining the
rules around wsc:ReplyTo (just a name I've picked for this email so I
can easily refer to it as being different to wsa:ReplyTo). As such,
anonymous may not even play in that space. Why would we want an
anonymous default? The current uses of wsa:ReplyTo really all assume
that it was present on the message. I'd prefer a binary approach for
wsc:ReplyTo.
An absent [reply endpoint] property in the XML infoset representation
becomes a receiver-inferred value of "anonymous" (actually, the URI
that means anon).
It seems preferable that we explicitly specify the value of "none"
(again, a URI in truth).
I would have expected us to be more specific: if there's a wsc:ReplyTo
present, then this is the destination that MAY/SHOULD/MUST be used for
sending a response. The absence means that no response is needed - no
default.
This is explicit, intuitively what one would expect for a one-way in
terms of HTTP handling, and avoids any ambiguity/under-specification if
a different representation is used at some future point.
The current wording banning use of anonymous reply-to addresses would
then be replaced.
I think we also need to ban use of message ids, and ban use of
fault-to, i.e. make it clear (by omission or by explicit statement)
that none of these aspects of the reply-processing rules and apparatus
are being put to use. ("Ban" in this context could mean "make it clear
that these properties, if present, will be ignored".)
We had discussed at the f2f that wsa:FaultTo is really meant just for
comms faults and "application faults" would be treated as messages. I'm
not sure if that made it into the minutes.
I think use of wsa:From tends to detract from the clarity obtained by
defining an extension property for our special use.
Mark.
Yours,
Alastair
Mark Little wrote:
Line 472 and 480.
Mark.
Ram Jeyaraman wrote:
Mark,
Could you please provide the PDF line numbers in the referred document
that are relevant to this issue. Thanks.
------------------------------------------------------------------------
*From:* Ram Jeyaraman [mailto:Ram.Jeyaraman@microsoft.com]
*Sent:* Friday, March 17, 2006 2:48 PM
*To:* ws-tx@lists.oasis-open.org
*Subject:* [ws-tx] Issue 30 - One-way message replies
This is identified as WS-TX issue 30.
Please ensure follow-ups have a subject line starting "Issue 30 -"
(after any Re:, [ws-tx] etc.)
===================================
Issue name: One-way message replies
Issue type: spec
Owner: Mark Little (mark.little@jboss.com)
Reference documents:
WS-AT specification:
http://www.oasis-open.org/apps/org/workgroup/ws-tx/download.php/17044/http://www.oasis-open.org/apps/org/workgroup/ws-tx/download.php/17129/wstx-wsat-1.1-spec-wd-04.pdf
<http://www.oasis-open.org/apps/org/workgroup/ws-tx/download.php/17044/http:/www.oasis-open.org/apps/org/workgroup/ws-tx/download.php/17129/wstx-wsat-1.1-spec-wd-04.pdf>
Description:
Currently we use wsa:ReplyTo for one-way messages in a way which
although legal in terms of the latest CR draft of WS-Addressing, has
led to confusion on a number of occasions. As an example, one use of
wsa:ReplyTo is on Prepare->Prepared, where Prepare has a wsa:ReplyTo
but the Prepared message is a separate (not response) message, because
it could be sent autonomously and not actually in response to Prepare.
The issue is that as far as WS-Addressing is concerned, wsa:ReplyTo
should really only be used in the case of the request-response MEP,
which is clearly not the case here.
Proposed Resolution:
The rules for where and when wsa:ReplyTo should be included and used
within WS-AT are well defined, and particularly in respect to the
interoperability scenarios. I propose that we replace wsa:ReplyTo with
something specific to WS-TX (perhaps wsc:ReplyTo, wsc:OnewayTo, or
somesuch).
Addendum:
Max suggested at the Raleigh f2f another potential resolution: that we
use wsa:From.
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