[jboss-as7-dev] Subsystem model version for AS8

David M. Lloyd david.lloyd at redhat.com
Mon Mar 4 13:51:54 EST 2013


I agree with Brian 100% on all points, FWIW.

On 03/04/2013 12:38 PM, Brian Stansberry wrote:
> I think continuing to address specific problems is important. For a
> number of reasons:
>
> 1) The standards we're trying to set for backwards compatibility IMHO
> need to keep increasing. My impression from discussions with the
> business side people behind EAP is that they agree. At some point we're
> going to need to be able to support some form of domain management
> across major product versions. I'd rather we work incrementally toward
> that by solving problems rather than punting and then have to figure out
> all the problems when someone forces the requirement.
>
> As an example, the current discussion on figuring out how to deal with
> deleted subsystems like CMP is useful. Similarly, I think it will be
> useful to figure out how to deal with a radical transition in a
> subsystem, a la what might happen with the web subsystem. Clearly we
> can't transform completely incompatible configs, but can both variations
> co-exist in a domain, with legacy server-groups running legacy profiles
> and other server groups running newer configs? That should be a solvable
> problem.
>
> 2) I fully expect demands to port AS 8 features back into EAP 6. It's
> going to happen. When it does, the compatibility requirement will
> suddenly appear. Better to address it when the feature is written than
> to expect people less familiar with the problem to add it during a port.
>
> 3) Transformation is a somewhat separate issue from backward
> compatibility for management clients, but we've found that doing and
> testing the transformation is real helpful in identifying client
> compatibility problems. Client compatibility is real important. We've
> promised many times that we won't willy-nilly break the client APIs even
> across major versions, so we need some kind of enforcement that we're
> not doing that.
>
> 4) I think the AS is going to be moving toward more rapid major
> releases. If we use each of those as an opportunity to break
> compatibility at will, our software will be uselessly unstable, and when
> the time comes to restore some compatibility guarantees for EAP, the
> task will be impossible.
>
> I also hope that given we're two years into the life of our subsystems
> that the "rapidly evolving" nature for most of their management APIs is
> about at an end. That should have been the case a year ago. Obviously
> there will always be new things getting added.
>
> On 3/4/13 9:02 AM, Paul Ferraro wrote:
>> It's not that there's a problem - it's just that we can't maintain backwards compatibility indefinitely, since the work required to do so grows exponentially (for rapidly evolving subsystems).  A major version bump seems like a natural breaking point - otherwise, what is the significance of incrementing to 2.0?
>> TBH - I mostly ask because I'm lazy and don't want to write transformers if I don't have to...
>>
>> Paul
>>
>> ----- Original Message -----
>>> From: "Brian Stansberry" <brian.stansberry at redhat.com>
>>> To: "Paul Ferraro" <paul.ferraro at redhat.com>
>>> Cc: "JBoss AS7 Development" <jboss-as7-dev at lists.jboss.org>, "Tomaž Cerar" <tomaz.cerar at gmail.com>
>>> Sent: Wednesday, February 27, 2013 8:23:26 PM
>>> Subject: Re: [jboss-as7-dev] Subsystem model version for AS8
>>>
>>> What's the problem going to be?
>>>
>>> On 2/27/13 7:10 PM, Paul Ferraro wrote:
>>>> Do the 2.x model versions need to be backwards compatible with 1.x
>>>> versions?
>>>> i.e. Do we need transformers to support a domain with mixed major
>>>> versions?
>>>> I hope not.
>>>>
>>>> ----- Original Message -----
>>>>> From: "Brian Stansberry" <brian.stansberry at redhat.com>
>>>>> To: "Tomaž Cerar" <tomaz.cerar at gmail.com>
>>>>> Cc: "JBoss AS7 Development" <jboss-as7-dev at lists.jboss.org>
>>>>> Sent: Monday, February 25, 2013 10:30:24 AM
>>>>> Subject: Re: [jboss-as7-dev] Subsystem model version for AS8
>>>>>
>>>>> Yes.
>>>>>
>>>>> On 2/25/13 9:24 AM, Tomaž Cerar wrote:
>>>>>> What about XSD schemas?
>>>>>>
>>>>>> probably same rule?
>>>>>>
>>>>>>
>>>>>>
>>>>>> On Mon, Feb 25, 2013 at 3:00 PM, Brian Stansberry
>>>>>> <brian.stansberry at redhat.com
>>>>>> <mailto:brian.stansberry at redhat.com>>
>>>>>> wrote:
>>>>>>
>>>>>>        Yes, major version bump please. This makes it
>>>>>>        straightforward
>>>>>>        to avoid
>>>>>>        version conflicts with EAP 6.x. If EAP 6.x needs to change
>>>>>>        API
>>>>>>        in more
>>>>>>        than a bug fix way, they can use a minor version with no
>>>>>>        fear
>>>>>>        that
>>>>>>        community AS has already used that # for something else.
>>>>>>
>>>>>>        On 2/25/13 7:11 AM, Tomaž Cerar wrote:
>>>>>>         > Hi,
>>>>>>         >
>>>>>>         > I remember few discussions on IRC in last weeks(s) about
>>>>>>         > how
>>>>>>         > to
>>>>>>        handle
>>>>>>         > version bumps for subsystem model when changes are done
>>>>>>         > on
>>>>>>         > AS8
>>>>>>        codebase.
>>>>>>         >
>>>>>>         > It was somewhat agreed that instead of bumping minor
>>>>>>         > version
>>>>>>         > we
>>>>>>        should
>>>>>>         > upgrade major version.
>>>>>>         >
>>>>>>         > aka instead of doing 1.2 --> 1.3, new version should be
>>>>>>         > 2.0
>>>>>>         >
>>>>>>         > That gives us flexibility of bumping minor version to 7.x
>>>>>>         > codebase if
>>>>>>         > need arises.
>>>>>>         >
>>>>>>         > I am writing this as there was some PRs lately that bump
>>>>>>         > just
>>>>>>        minor version.
>>>>>>         >
>>>>>>         > So, can we get an agreement of new versioning rules, that
>>>>>>         > we
>>>>>>         > will
>>>>>>        then
>>>>>>         > follow.
>>>>>>         >
>>>>>>         > I personalty favor major version bumps...
>>>>>>         >
>>>>>>         >
>>>>>>         > --
>>>>>>         > tomaz
>>>>>>         >
>>>>>>         >
>>>>>>         >
>>>>>>         >
>>>>>>         >
>>>>>>         > _______________________________________________
>>>>>>         > jboss-as7-dev mailing list
>>>>>>         > jboss-as7-dev at lists.jboss.org
>>>>>>         > <mailto:jboss-as7-dev at lists.jboss.org>
>>>>>>         > https://lists.jboss.org/mailman/listinfo/jboss-as7-dev
>>>>>>         >
>>>>>>
>>>>>>
>>>>>>        --
>>>>>>        Brian Stansberry
>>>>>>        Principal Software Engineer
>>>>>>        JBoss by Red Hat
>>>>>>        _______________________________________________
>>>>>>        jboss-as7-dev mailing list
>>>>>>        jboss-as7-dev at lists.jboss.org
>>>>>>        <mailto:jboss-as7-dev at lists.jboss.org>
>>>>>>        https://lists.jboss.org/mailman/listinfo/jboss-as7-dev
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Brian Stansberry
>>>>> Principal Software Engineer
>>>>> JBoss by Red Hat
>>>>> _______________________________________________
>>>>> jboss-as7-dev mailing list
>>>>> jboss-as7-dev at lists.jboss.org
>>>>> https://lists.jboss.org/mailman/listinfo/jboss-as7-dev
>>>
>>>
>>> --
>>> Brian Stansberry
>>> Principal Software Engineer
>>> JBoss by Red Hat
>>>
>
>


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