web-application deployment

[scp]

Hi,

I have one big web-application(running in tomcat container) which inturn contains some plug-ins.Each plug-in is associated with a spring application context.In order to support versioning of plug-ins I would like to move to OSGi+Spring.I want to make each plug-in a spring powered bundle.This way, I can also install/uninstall the plug-in bundles without stopping the web-application.

Now the question is, how do I deploy these bundles in Tomcat?I understand I have the following options.

option 1: Embed OSGi platform inside my web application,then use Spring DM(extender)to discover my spring powered plug-in bundles.I will use an equinox servlet bridge for web support.

option 2: The Spring-DM way,by OSGIfying my tomcat container and then deploying my web-application as WAR bundle.
a)Can I still have the spring powered plug-in bundles inside my main web-application WAR bundle, as there is no need to share them across multiple web-applications?
b)With OSGIfied tomcat container,concurrently can I still run other non-osgi web-applications?



When we should choose option1 or option2?


Thanks in advance

regards
SCP

[Costin Leau]

Currently there are several options in the Spring realm:

a. use servlet bridge (i.e. deploy OSGI inside Tomcat)
b. use Spring DM web support (deploy Tomcat inside OSGi)
c. use dm Server

Note that with the upcoming RFC-66 spec, b is being deprecated. You can read more about it here:
http://blog.springsource.com/2009/05...web-container/
http://blog.springsource.com/2009/06...for-dm-server/

As for pluggable web apps, this entry offers some good insight (in my opinion):
http://blog.springsource.com/2009/06...source-slices/

[Costin Leau]

I just realized that I didn't give a clear answer to your questions because "it depends". I think the RFC-66 is an important step forward so if you have time, I'd advice you to investigate and use a similar setup.
If that's not an option then I would opt for dm Server followed by the Spring DM setup.

[templth]

Hi Costin,

Thanks for the hint! So, if I correctly understand, it's better now to use the RI of OSGi Web Container (RFC 66) available in the dm Server but this approach doesn't require to use the whole dmServer...
In which version of Spring DM, the web support will be removed?
Thanks,
Thierry

[Costin Leau]

Hi Thierry,

the answer would be yes. Of course, the spec is still in the works so some things might change but overall, it's a much better alternative. Fundamentally, things are more or less the same since there is really no API that one codes against. However, from a maintenance perspective, using a standardized mechanism is better.