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From Jeremy Boynes <>
Subject Re: online and offline deployment
Date Sun, 07 Nov 2004 22:54:18 GMT
I think there is a misconception here between what is supported and what 
is recommended. There have been a lot of bad ideas in the past (EJB1.0 
DD anyone?) and people have tried to improve on them. I don't think we 
need to make bad ideas from the past the recommended way of doing things 
even if we support them.

More specific comments inline.

Aaron Mulder wrote:
> On Sun, 7 Nov 2004, David Jencks wrote:
>>I don't think "drop, wait & wonder" hot deployment should be supported.  
>>  This only supports deployment of applications with embedded plans or  
>>applications that need no plan. 
> 	I don't understand the objections to this.  "embedded plans" is 
> the way every J2EE application I've ever seen has worked, save the days 
> when WebSphere made you save your plan to DB2 instead of XML files.  Every 
> tool in the space today puts your plans in the archive.

The biggest objection to this is the way in which you have to crack open 
multiple levels of archive in order to add the deployment information. 
Not only is this a PITA but it also compromises the provenance of the 
supplied archive - any original signature is lost.

> 	Granted, the current J2EE leadership seems to think that no
> application archive should contain server-specific information, but that
> is not a standard, that is a paradigm shift.  Don't you think it will take
> a long time before the average J2EE developer stops trying to pack their
> server-specific deployment descriptor (or "deployment plan") into their
> archives?  Refusing to support the by-far-most-common method of J2EE
> packaging and deployment is IMHO only going to turn people off to the
> product, even if you argue that it's "more correct".

No one is refusing to support this - in fact, it is already fully 
supported. We just recommend using an external plan.

> 	This is still a different issue than offline deployment, though, 
> since a directory scanner would only work while the server was online.  As 
> well, I'd be fine if the directory scanner declined to deploy anything 
> without a Geronimo plan, or just produced errors along the lines of 
> "unable to resolve reference to foo, please include a Geronimo deployment 
> plan (geronimo-jetty.xml)"...

Again, I don't think anyone is refusing to support this - David and I 
just don't think it's a good idea for technical reasons such as 
incompatibility with JSR-88, reliance on proprietary embedded plans, 
copy problems, non-deterministic outcomes, ...

If someone implements this (dealing, of course, with all the nasties) 
then all the better; in fact, IIRC there is some old scanning code of 
mine lying around in the repo somewhere.

However, due to the technical issues I would still not advocate scanning 
as being the recommended way of "deploying" an application into Geronimo.


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