Title: Message
Please keep in mind
that saying that BPEL should offer a BP-compliant service only
means that at least one WSDL port offered by the BPEL process has to be
BPEL-compliant. The BPEL process could provide additional non-compliant ports
and still be considered BP-compliant.
Ugo
-----Original Message-----
From: Furniss, Peter
[mailto:]
Sent: Thursday, October 02,
2003 2:30 AM
To: BPEL OASIS
Subject: [wsbpel] Issue - 72 -
( was RE: [wsbpel] Issue 47 and WS-I BP 1.0)
I
would strongly support Postel's law in general, but I'm not sure it applies so
easily to BPEL.
The
detailed content and format of particular messages sent from (be conservative)
or received by (be liberal) a BPEL process are obviously subject to Postel's
law, but that's a matter for the binding and the involved protocols, and their
profiles.
The
equivalent for BPEL would first appear to be, as Ron says, be liberal in
the web services you use, conservative in the ones you offer. However,
the use/offer polarity is determined by the WSDL MEP's in use.
In
the case of asynchronous relationships, where there are
paired port types one-way operations, there isn't any obvious
distinction as to which side is doing the specifying and which
is obediently following it. Even for request/response patterns, it
isn't invariably the case that the server has freedom to choose (and thus to
obey BP 1.0) and the client has to follow the dictates of the server (whether
it obeys BP 1.0 or not), which is the basis of Postel's
law.
For
BPEL, or indeed for business protocols in general, which side has the
initiative is probably determined by other features (which side has more
economic clout or more deployed implementation or less intelligent developers
or got there first). Postel's law applies as something like "be generous in
what you demand of others, providing there is unambiguity; be precise in how
you follow the demands of others, even if it doesn't seem entirely
reasonable".
Peter
-----Original Message-----
From: Ron Ten-Hove
[mailto:]
Sent: 01 October 2003
21:48
To: Eckenfels. Bernd
Cc: BPEL
OASIS
Subject: Re: [wsbpel] Issue 47 and WS-I BP
1.0
Perhaps we should invoke Postel's
law, with respect to basic profile conformance. To promote interoperability,
we should be as permissive as possible when dealing with (other) web
services, but as conformant as possible when creating our own (BPEL engine
provided) web services.
I realize this falls
mostly on implementations to worry about, but the basic profile does contain
a lot of restrictions and clarifications for the "abstract" service model
that may be of interest.. The ban on operation overloading might be slightly
simplifying, for example.
Anyway, a quick scan of
the BP didn't reveal anything scary to me. It seems to me that WS-I BP 1.0
compliance will be an implementation worry, but as a technology that will
rely on interoperation of our SOAP infrastructure, we ought to encourage
(but not mandate) BP compliance.
-Ron
Eckenfels. Bernd
wrote:
Hello Ugo,
I think it is not good to speak about violation if an
implementation is able to communicate with an larger number of
systems.
Perhaps we should chnage this: "conformant BPEL engines must be
able to provide and consume Web Services according to BP 1.0a
specification. Engine should not provide Web Services with HTTP SOAP
binding other than BP1.0 conformant.
Actually I see the point of requiring BP1.0 support as a
conformance rule, but I dont see a point of restricting engines to that,
even if it applies.
Mit freundlichen Grüßen
Bernd
Eckenfels
Chief
Architect
--
SEEBURGER AG - Edisonstr.1 , D-75015 Bretten,
Germany
Fax: +49 (0)7252 96-2400 - Phone: +49 (0)7252
96-1256
mailto: - http://www.seeburger.de
-----Original Message-----
From: Ugo Corda [mailto:]
Sent:
Wednesday, October 01, 2003 8:28 PM
To: Satish Thatte; Prasad
Yendluri; Eckenfels. Bernd
Cc: BPEL OASIS
Subject:
RE: [wsbpel] Issue 47 and WS-I BP 1.0
Right, RPC
literal would be fine, but RPC encoded would be in
violation.
-----Original Message-----
From: Satish Thatte [mailto:]
Sent:
Wednesday, October 01, 2003 11:23 AM
To: Ugo Corda; Prasad
Yendluri; Eckenfels. Bernd
Cc: BPEL OASIS
Subject:
RE: [wsbpel] Issue 47 and WS-I BP 1.0
So for
instance the RPC encoded services bound to SOAP/HTTP would be in the
“in scope but in violation” category?
From: Ugo
Corda [mailto:]
Sent: Wednesday,
October
01, 2003 11:18
AM
To:
Satish Thatte; Prasad
Yendluri; Eckenfels. Bernd
Cc: BPEL OASIS
Subject: RE: [wsbpel] Issue 47
and WS-I BP 1.0
Let me
clarify point 4 (sorry, I mislabeled it as 3) in relation to point
1.
I think
we should distinguish services that are not compliant with BP 1.0 from
those that are simply out of scope for BP 1.0.
If I
have a Web service that is not bound to SOAP/HTTP, then I would say it
is out of scope for BP 1.0, so it's OK for BPEL to interact with
it.
My
point 4 is about services that are within the scope of BP 1.0 and
still do not comply with its requirements.
Ugo
-----Original
Message-----
From:
Satish Thatte [mailto:]
Sent: Wednesday, October 01,
2003 11:09
AM
To:
Ugo Corda; Prasad Yendluri
Cc: BPEL OASIS
Subject: RE: [wsbpel] Issue 47
and WS-I BP 1.0
I doubt
that we can mandate BPEL to be used with BP 1.0 compliant services
only especially given the answer to 1 assuming it is correct, and
given that there are many services today that are not compliant
(e.g., RPC encoded ones).
From: Ugo
Corda [mailto:]
Sent: Wednesday,
October 01, 2003 10:55 AM
To: Satish Thatte; Prasad
Yendluri
Cc: BPEL
OASIS
Subject: RE:
[wsbpel] Issue 47 and WS-I BP 1.0
I see
a few separate issues/questions connected to the relationship
of BP 1.0 and BPEL.
1- Would
BP 1.0 be restricting BPEL to the point that some of BPEL's
functionality would not be available?
I
cannot think of any such restriction off the top of my
head.
2-
Would the fact that BP 1.0 only addresses the SOAP/HTTP binding
imply that also BPEL should be limited to that type of
binding?
I
don't think that anybody would imply that.
3-
Should a BPEL process be offered as a Web service that is BP 1.0
compliant?
My
answer would be yes.
3-
Would it be fair to limit BPEL use to interacting with BP 1.0
compliant Web services only?
My
personal answer would be yes. But I am a member of WS-I, and I
understand other people might have different
answers.
Ugo
-----Original
Message-----
From: Satish Thatte [mailto:]
Sent: Wednesday, October 01,
2003 10:39
AM
To:
Prasad Yendluri
Cc: BPEL OASIS
Subject: RE: [wsbpel] Issue
47 and WS-I BP 1.0
For the
benefit of the non-expert could post a salient example
please? Specifically, a BPEL usage pattern that would not
work if BP 1.0 is followed but would work if any WSDL 1.1 portType
is allowed. In other words, is BP 1.0 a restriction on the
WSDL artifacts we use or potentially on BPEL
itself?
From:
Prasad Yendluri [mailto:]
Sent: Wednesday,
October 01, 2003 10:11 AM
To: Satish Thatte
Cc: BPEL OASIS
Subject: Re: [wsbpel] Issue
47 and WS-I BP 1.0
The sections 5.5 and 5.6 in the basic
profile (http://www.ws-i.org/Profiles/Basic/2003-08/BasicProfile-1.0a.htm)
are devoted to binding aspects but, several major sections
including section 4, other sections of 5 address abstract aspects
of WSDL, which is a pretty large portion. All those are applicable
BPEL IMO.
Prasad
Satish
Thatte wrote:
Most of the BP 1.0
directives are binding related. BP also forbids outbound
operations which BPEL does not use. Can someone identify a
directive in BP 1.0 that actually affects
BPEL?
Satish
