Re: One-way messaging in SOAP 1.2

(RESEND - this didn't seem to make it out the first time)

Jacek Kopecky wrote:

 >  as far as I understand the HTTP binding (I've last read the
 > SOAP/1.1 version of it though) is that it supports one-way quite
 > nicely:
 >  An HTTP request with the SOAP Envelope in it goes there, back
 > goes either 202 success, but nothing back, or 200 OK with content
 > length zero. (IIRC the wording meant "in case there is a reply,
 > send it like this:...")
 >  If the current wording prohibits one-way, I think we've indeed
 > got an issue here.

The current wording doesn't prohibit it, but it doesn't enshrine it either:

"8.3 Supported Transport Message Exchange Patterns

An instance of a transport binding to HTTP[2] conforming to this
transport binding specification MUST support the following transport
message exchange pattern:

(see 7.1 Single-Request-Response TMEP)"

Note no mention of one-way.

 >  I don't think we necessarily have to describe one-way MEP for it
 > should be clear enough. Or we could have a simple definition
 > like:
 >  One-way MEP: best effort to get the message to the other side,
 > nothing (SOAPish) ever goes back.

You could say the same about request-response, but instead we describe
it quite formally. If we are going to say that every binding MUST
support a one-way MEP then we should at least define it formally IMO.

 >  I don't like the idea that some transports may not support
 > one-way, I can't imagine such a transport really.

It's not a question of the transport, but of the binding: how does the
binding use the transport to do one-way. Our HTTP binding doesn't call
out that it supports a one-way MEP, but does imply it in the description
of the 202 and 204 status codes.


 > On Wed, 16 Jan 2002, Marc Hadley wrote:
 >  > All,
 >  >
 >  > I'd like to raise a new issue:
 >  >
 >  > In Part 1, section 5.3 we find:
 >  >
 >  > "Every binding specification MUST support the transmission and
 >  > processing of one-way messages as described in this specification. A
 >  > binding specification MAY state that it supports additional 
features, in
 >  > which case the binding specification MUST provide for maintaining 
 >  > performing processing, and transmitting information in a manner
 >  > consistent with the specification for those features."
 >  >
 >  > This paragraph is potentially confusing, either we mean:
 >  >
 >  > (i) All bindings must support a one-way MEP, in which case there 
are two
 >  > issues:
 >  >    (a) we currently don't define a one way MEP in the specification
 >  >    (b) the HTTP binding we do define doesn't support a one-way MEP
 >  >
 >  > or (my reading)
 >  >
 >  > (ii) All bindings must at a minimum define how to move a message from
 >  > one node to another, in which case I would propose that we add a
 >  > clarification along the lines of "Note, this does not mean that all
 >  > bindings must support a one way MEP, only that they MUST define 
how to
 >  > move a message from one SOAP node to another".
 >  >
 >  > Comments ?
 >  >
 >  > Regards,
 >  > Marc.
 >  >
 >  >

Marc Hadley <>
XML Technology Centre, Sun Microsystems.

Received on Wednesday, 16 January 2002 09:35:31 UTC