[jboss-as7-dev] HornetQ subsystems in AS 7

Wed Apr 6 16:44:51 EDT 2011

I don't see any technical reason they can't be combined; i.e. there's 
nothing about the AS 7 architecture that says these need to be separate 
subsystems.

The basic issue is configuration. The xsds for the current 2 subsystems 
were almostly 100% lifted from the hornetq-jms.xsd and 
hornetq-configuration.xsd. Those two xsds both have a "queueType" but 
the meaning is different. If we combine the two subsystems into one, 
that means we combine the schemas and the management resource trees and 
we need to make sure it is very intuitive for users to understand what 
it is they are configuring and how to configure commonly used things.

We need to do that whether or not we combine into a single subsystem, 
since it's clearly not intuitive now.

On 4/6/11 3:20 PM, Andrig Miller wrote:
>
>
> ----- Original Message -----
>> From: "Clebert Suconic"<csuconic at redhat.com>
>> To: "Andrig Miller"<anmiller at redhat.com>
>> Cc: "Brian Stansberry"<brian.stansberry at redhat.com>, "jboss-as7-dev at lists.jboss.org Development"
>> <jboss-as7-dev at lists.jboss.org>
>> Sent: Wednesday, April 6, 2011 2:17:15 PM
>> Subject: Re: [jboss-as7-dev] HornetQ subsystems in AS 7
>> Well... Topic subscriptions are just Queues.
>>
>> There are advantages of using the HornetQ API directly... Especially
>> on Asynchronous ACKs.
>>
>> Although I don't understand exactly why you need a separate module on
>> AS7 for this. This is just a simple POJO being accessed through the
>> classloader. (hornetq-core.jar, and hornetq-core-client.jar)
>>
>
> Yeah, I don't see why that would be necessary either.  Using the core API directly is fine, and can be exposed in the module along with JMS.
>
> Andy
>
>>
>> On Apr 6, 2011, at 3:14 PM, Andrig Miller wrote:
>>
>>> Personal take on this, is that there shouldn't be two. The
>>> astonishment below about only have queue's and not topics is a
>>> direct result of this separation, because the implementation details
>>> underneath JMS, in terms of HornetQ, is that there are only queues,
>>> even though topics are fully support, but its still just a queue
>>> underneath.
>>>
>>> This is a problem in my mind.
>>>
>>> Andy
>>>
>>> ----- Original Message -----
>>>> From: "Brian Stansberry"<brian.stansberry at redhat.com>
>>>> To: "jboss-as7-dev at lists.jboss.org Development"
>>>> <jboss-as7-dev at lists.jboss.org>, "Clebert Suconic"
>>>> <csuconic at redhat.com>
>>>> Sent: Wednesday, April 6, 2011 1:15:04 PM
>>>> Subject: [jboss-as7-dev] HornetQ subsystems in AS 7
>>>> Copied below is a discussion we had today on #jboss-as7 in IRC that
>>>> I'm
>>>> copying here to get input from the HQ folks.
>>>>
>>>> AS 7 currently has 2 HQ-related subsystems, "messaging" which
>>>> provides
>>>> core HQ, and "jms" which brings in JMS spec compliance. The gist of
>>>> the
>>>> discussion is 1) whether this separation is overly unintuitive and
>>>> 2)
>>>> if
>>>> it's necessary, is the name "messaging" for the core HQ subsystem
>>>> too
>>>> likely to lead users to assume it's where JMS topic/queue creation
>>>> is
>>>> done.
>>>>
>>>> The conversation is below. It carried on after the following;
>>>> please
>>>> see
>>>> http://echelog.matzon.dk/logs/browse/jboss-as7/1302040800 if you
>>>> are
>>>> interested.
>>>>
>>>> pilhuhn: Also I am astonished that Q s are present , but not Topics
>>>> [1:52pm] bstansberry: pilhuhn: there are topics in the jms
>>>> subsystem
>>>> [1:53pm] bstansberry: the "messaging" subsystem is very oriented
>>>> toward
>>>> core HornetQ
>>>> [1:54pm] bstansberry: Nihility: ^^^ reminds me of our discussion w/
>>>> paul
>>>> re: the JGroups subsystem, where we decided it was silly to give a
>>>> "generic" name to a subsystem that was not exposing a standard API
>>>> [1:55pm] bstansberry: same applies to subsystem=messaging
>>>> [1:55pm] pilhuhn: so Qs are in both? messaging and jms? feels
>>>> strange
>>>> [1:55pm] Nihility: bstansberry: makes sense
>>>> [1:55pm] Nihility: bstansberry: sort of
>>>> [1:55pm] Nihility: bstansberry: another example is subsystem=web
>>>> [1:56pm] Nihility: bstansberry: which is jboss web
>>>> [1:56pm] bstansberry: well, that at least is exposing the Servlet
>>>> spec
>>>> [1:56pm] dmlloyd: shared global bindings are a nasty little problem
>>>> [1:56pm] Nihility: i think our goal should just be to have
>>>> subsystem
>>>> names
>>>> [1:56pm] Nihility: that are intuitive easy to understand
>>>> [1:57pm] Nihility: jgroups vs group-communication is basically the
>>>> same
>>>> to me
>>>> [1:57pm] dmlloyd: jgroups is unambiguous and concise imo
>>>> [1:57pm] bstansberry: yes, that's decided
>>>> [1:57pm] Nihility: yes
>>>> [1:57pm] dmlloyd: hornetq should be hornetq
>>>> [1:57pm] Nihility: the reason for messaging and jms is different
>>>> [1:57pm] pilhuhn: I think it needs to be clear that for an enduse,
>>>> that
>>>> he wants to have a jms/queue and not a messaging/queue when doing
>>>> jms
>>>> [1:58pm] dmlloyd: jms should be jms
>>>> [1:58pm] Nihility: they realy do have two subsystems
>>>> [1:58pm] dmlloyd: if there is such a generic notion
>>>> [1:58pm] bstansberry: right, so calling hornetq "messaging" is not
>>>> intuitive
>>>> [1:58pm] Nihility: they have this notion of a lightweight topic
>>>> [1:58pm] bstansberry: people will gravitate toward it
>>>> [1:59pm] pilhuhn: Yeah leightweight.. it will float in the clouds
>>>> [1:59pm] Nihility: and thats what they think is a real messaging
>>>> api
>>>> [1:59pm] pilhuhn: .oO( DId I win as BS-Bingo? )
>>>> [1:59pm] Nihility: jms is just something extra they do for the spec
>>>> [1:59pm] Nihility: with extra requirements etc
>>>> [1:59pm] Nihility: so its like a higher level layer
>>>> [1:59pm] Nihility: so they have core messaging
>>>> [1:59pm] Nihility: and they have jms
>>>> [1:59pm] Nihility: and togheter thats hornetq
>>>> [1:59pm] bstansberry: good point
>>>> [2:00pm] bstansberry: ok, no JIRA, at least not from me
>>>> [2:01pm] bstansberry: instead, a dev list thread and the HQ people
>>>> can
>>>> deal with it
>>>> [2:01pm] pilhuhn: The admin that wants to use a MessageDrivenBean
>>>> does
>>>> not really care about that separation
>>>> [2:02pm] Nihility: the separation is more because you can run hq
>>>> without
>>>> starting the jms services
>>>> [2:02pm] Nihility: and they have separate configuration
>>>> [2:02pm] pilhuhn: yep
>>>> [2:02pm] Nihility: although you could collapse the two
>>>> [2:02pm] Nihility: emuckenhuber and i debated that for awhile
>>>> [2:02pm] Nihility: we had a hard time deciding
>>>> [2:03pm] pilhuhn: What I want to express (and that targets rather
>>>> us
>>>> with JON and the console) is that for this said admin it needs to
>>>> be
>>>> totally clear that he wants to go to subsys/jms/queue
>>>>
>>>> --
>>>> 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