| [Thread Prev]
| [Thread Next]
| [Date Next]
| [Thread Index]
| [List Home]
Subject: [ISSUE 132] Rebuttal: Against the use of portability and functions asreasons for requiring one of the existing 4 languages
- From: Mike Edwards <email@example.com>
- To: "OASIS Assembly" <firstname.lastname@example.org>
- Date: Tue, 23 Jun 2009 15:03:10 +0100
Thanks for your comments.
First, I would like to point out that
we have built the Assembly testcase suite along the lines that you
want to see. It is built in a
way that is language independent with all top level materials being
wholly composite based, and then with
replaceable language-specific implementations at the
Availability of the testcase suite in
each of the OASIS supported language types is not a "convenience"
- it is a requirement. We already
have Java, and C, C++ and BPEL are well advanced. Others will be
added as their specifications come forward
to public review.
The second point about the testcase
suite is that it is not just a matter for the SCA runtime implementers.
The idea is that the conformance testcase
suite is available to all - anyone can take it and use it to
verify that some SCA runtime conforms
to the specifications. It is the open nature of the test suite that
is the biggest guarantee that SCA runtime
vendors will take it seriously - no one can bend their way
around it without facing the possibility
that users will catch them out.
The second question to address is what
you really think it means to "conform" to the SCA specifications.
One important thing is that SCA is extensible
and can accommodate the use of pretty well any implementation
technology and implementation language.
Any vendor can do this at any time. So SCA is very much open,
as you desire.
However, claiming conformance is something
else. What does "claiming conformance" really mean?
To me, it means that the SCA runtime
meets the requirements of the relevant SCA specifications.
I am sure there is real value to end
users in a claim of conformance - the end users can have expectations
of a conforming system that it will
work in a certain way - and that the end users knowledge of SCA will apply
to the conforming system. It is
clear that vendors also attach importance to claiming conformance too.
If conformance is to have any real meaning,
I believe that this must mean adhering to the letter of the spec.
Our current approach to this is to require
the passing of the test suite - as a minimum check. There will always
be things that the test suite does not
check - and for those, the wording of the conformance points in the spec
is the tool that people can use.
So, let us say that we want a more "open"
approach to claiming conformance for a runtime that supports
one or more implementation languages
not specified by any of the OASIS TCs. How might we do this while
still retaining some meaning to the
term "conformance"? Some thoughts:
- Might we allow a claim of conformance
for language "X" as long as there is a Test Suite for Assembly
uses implementation language "X"?
- Might we allow a claim for conformance
for language "X" as long as there is a specification for SCA
implementations written in lnaguage
"X"? Without such a specification and in particular without
a definition of
how the componentType is calculated
for an implementation artifact written in language "X", how would
possible to know that the test suite
was a valid test suite?
- Should it be required that the test
suite and the specification for language "X" is available publicly
form of open terms? I note that
the current OASIS TC specs and test suite are available to anyone on open
terms - so that anyone can take them
and run them.
What are your thoughts on this?
Strategist - Emerging Technologies, SCA & SDO.
Co Chair OASIS SCA Assembly TC.
IBM Hursley Park, Mail Point 146, Winchester, SO21 2JN, Great Britain.
Phone & FAX: +44-1962-818014 Mobile: +44-7802-467431
||Jim Marino <email@example.com>
||OASIS Assembly <firstname.lastname@example.org>
||[sca-assembly] Rebuttal: Against the
use of portability and functions as reasonsfor requiring one of the existing
I haven't had much time lately to participate in TC discussions on
language conformance due to other commitments. However, I did have the
opportunity to discuss the technical merits of this issue at length
with people from Microsoft. I think I understand where they are coming
from and believe there may be a way to accommodate Microsoft's
concerns while also improving the SCA specifications.
Coupling conformance to the Assembly specification with one of the
"official" TC languages places an unneeded and expensive burden
potential implementors that may not support one of those languages.
This is particularly evident given the OASIS requirement for two
independent conformant implementations. The original spirit of
assembly was language independence and that can be maintained. It
seems the main sticking point is with conformance testing: namely, how
can language independent tests be created that verify assembly
As a proposal, I believe it is feasible to use composite
implementations to create language independent verification tests. The
tests would make extensive use of the implementation.composite type as
well as service and reference promotions. The actual implementations
would be contained in a separate contribution (or contributions) and
made available to the using composite via the contribution import/
export mechanism. The verification tests would be run against the
components using the composites and their promoted services, which
would result in language independent conformance checks.
As a convenience, composites which used "official" language types
as implementation.java or implementation.bpel could be made available.
However, it would also be possible for a vendor to supply their own
composites that used a proprietary language.
Making assembly truly language independent would have two significant
benefits, specifically portability and expanding SCA's relevance.
Realistically, the best chance of achieving portability for SCA is at
the assembly level. The further one goes "down" - e.g. into policy,
component implementations, and actual application code - portability
becomes problematic. For example, policy is not likely to be portable
given the ability to use different policy languages. The Java
specification also does not address many of the areas required to
write portable applications such as database access and using managed
threads. If Java EE is any indicator, achieving portability of
application code is likely to require years of effort, and even then
the results are likely to be incomplete. However, in my opinion,
portability at the assembly level is a realistic goal and should be
pursued by making it as language independent as possible.
Language independence would also expand the relevance of assembly to
areas Java EE could never touch. Assembly can be used across a host of
proprietary programming languages, essentially providing a portable
blueprint of systems, regardless of the technologies they run on. In
my opinion, this may prove to be the most important contribution SCA
has to make.
To unsubscribe from this mail list, you must leave the OASIS TC that
generates this mail. Follow this link to all your TCs in OASIS at:
Unless stated otherwise above:
IBM United Kingdom Limited - Registered in England and Wales with number
Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6
| [Thread Prev]
| [Thread Next]
| [Date Next]
| [Thread Index]
| [List Home]