Is it possible to run Jboss 4.2.3 as a bundle inside OSGI container? What would be the challenges associated with it?
For those who cares, I am looking at running dcm4chee inside OSGI.
While not impossible it would be incredibly hard, a simpler alternative would be to embed OSGi inside JBoss, see:
http://felix.apache.org/site/apache-felix-framework-launching-and-embedding.html
and
Programmatically Start OSGi (Equinox)?
and
http://njbartlett.name/2011/03/07/embedding-osgi.html
http://www.dcm4che.org/jira/browse/DCM-308 Looks like they're adding support to make the Jars valid bundles - couldn't you just work out the dependencies and deploy these to an OSGi framework? OSGi has support for JMX and JNDI.
Unless there are huge dependencies on JBoss' internals, I'd suggest the second option, but beware of Class.forName usage and other non-osgi-friendly code.
I logged the bug specifically for the dcm4che (note 1 e) toolkits, not the dcm4chee war. I would suggest logging a new issue for the dcm4chee assembly. However, making the dcm4che toolkit components osgi bundles would likely be a required step in the direction of getting dcm4chee to run in an osgi container.
Related
I am trying to embed Felix in an application of ours to handle plugins. Everything is working fine, however, development and debugging is very cumbersome.
Is there a solution where I can tell Felix to automatically reload a plugin bundle or its classes when I recompile a plugin in Eclipse?
I cannot use any OSGi specific launchers because Felix is embedded in our application
Felix' fileinstall supports directories, but expects a specific structure, which is incompatible with the layout of the Eclipse project.
Any help or pointers to a solution would be greatly appreciated.
You could take a look at Bndtools and the remote launcher. You only need to install a remote agent in your framework and then Bndtools can update any bundle that has changed in the workspace.
This is explained in remote launching. In OSGi enRoute you find an IoT tutorial that uses this model as well as a Karaf App Note.
i' ve some web applications developed using Seam Framework 2.3 + jBoss AS 7 + Hybernate.
Since i' ve been studying OSGI for a while, i was wondering if is possible to move my applications to the osgi world for modularizing everything; i' ve read a lot of blogs and these interesting discussions as well (how-to-modularize-an-enterprise-application-with-osgi-and-ee6 and how-to-modularize-a-jsf-facelets-spring-application-with-osgi) but honestly i still don't really know where i should start from, since i' ve never used OSGI before.
According to you
Is it possible (and useful) do such things?
According to your experience, what would be a good starting point?
Thanks for help
Approach
Possibly start with a toy application as a spike, a WAB (OSGi WAR) and single service bundle.
Definitely take an iterative approach. As far as I know JBoss supports the mixing of OSGi services and Java EE stuff, via JBoss modules/msc, this will allow you to try OSGi and migrate gradually.
I think you'll find some things are incredibly easy and others very hard, so pick easy battles while you're getting familiar. In the end you may stick with a hybrid approach.
Build
What's your build tool? Mostly like Maven or Ant, in which case have a look at maven-bundle-plugin
or bnd respectively. You'll need to ensure the OSGi metadata is present in each of your bundles (Bundle-SymbolicName, Import-Package, Export-Package, etc). If you're using Maven see this answer.
It can be tricky to divide a monolithic app into modules, but as a general rule when you migrate a reasonable sized module you should have separate bundles for API and implementation (which is good design anyway but has implications for the runtime too).
Interop
You can acquire OSGi services, access bundles etc using the low level framework APIs from an injected BundleContext, which will give you a low-level programmatic hook into OSGi. It should be as simple as:
#Resource
BundleContext context;
Unless your Java EE code is packaged as JBoss modules I don't think it will be easy for you to call the other way (e.g. OSGi service looking up Java EE service) without resorting to something like JNDI.
You should be able to install the webconsole and see what Java EE bits are registered in OSGi, and similarly check JNDI to see what's available OSGi for Java EE.
Migrating Services
While OSGi is a lot of fun, using the raw framework API results in quite a bit of boilerplate code and it's unlikely you'll need the power or want the coupling. You can use a number of dependency injection frameworks on top of OSGi; blueprint (Spring-like), Peaberry (Guice) and Declarative Services for example.
I'm biased but Declarative Services has a strong affinity to the OSGi µservice model and the implementations are lightweight.
CDI
I don't know much about Seam/CDI, but Pax CDI might help (though JBoss might already have covered this).
Web
Are you planning to have a highly modular UI with hot deploy of the various components? If not then probably best just to package the UI as a WAB. A WAB is a skinny WAR (i.e. it imports rather than embeds most dependencies). Even if you're after a highly modular, dynamic frontend, I would definitely do this for the first pass.
JPA
A word of warning - JPA implementations typically don't play well in OSGi environments, you may want to look at Apache Aries or Eclipse Gemini. Another option might be to leave the JPA stuff in Java EE space and access Java EE DAOs/Repositories as OSGi services. Again though you may experience some classloading issues.
Possibly useful examples https://docs.jboss.org/author/display/JBOSGI/Provided+Examples
Is there a way to run an OSGi container in the Weblogic Application Server? I know that it works with JBoss, Glassfish and there are possibilities to add an Equinox servlet bridge to your OSGi project (implementation of the bridge is too old). But I want something similar to JBoss/Glassfish functionality where it is very easy to deploy your OSGi environment, because there are already OSGi implementations. Most of the articels I found were very old and there are no more recent ones. Can someone help with hints or better some links?
Maybe Bnd could create a .war file for me, but how can I achieve it. I read there is a possibility. Example would be great!
EDIT
Just for those who still look into that case. Since version 12.1.2 Weblogic supports OSGi out-of-the-box.
I'd consider the Apache Felix Http bridge. It worked a lot better for me than the ancient Equinox bridge (I messed around with it for a while, but never got it to work well), after I switched to Felix I got something working pretty quickly.
If I understand you correctly, you want to make a 'plain' war file, that can be deployed in any Java EE server. If that's the case, there is nothing OSGi about your war file, so I don't think Bnd will do anything for you.
WebLogic now supports OSGi in version 12.1.2 . See this
Ok I'm having quite some issues setting both jbpm and jboss working together...something as simple as running the jbpm process from a servlet is trunning to be a pain and all because jBoss can't find classes.
I made a Dynamic Web Project and didn't use Maven project so things are cleaner...and because it should work.
I just want to load a jbpmn2.0 from the repository in a servlet and run it using a WorkItemHanlder....but I get this:
java.lang.ClassNotFoundException: org.drools.runtime.process.WorkItemHandler
For some reason jBoss can't find a class from jBPM that should work on JBoss. What I did....and I think it's not the right solution...was add the knowledge-api.jar to the WEB-INF/lib. Although I can now deploy the app when I try to run it I get:
Error Unable to instantiate service for Class 'org.drools.builder.KnowledgeBuilderFactoryService'
I Honestly don't get why is it so hard to make a Jboss Web app using jBpm.
You need to make sure all dependencies are on your classpath, this is the same for all Java applications (not just jbpm) and application servers (not just JBossAS).
Which jars did you add? Depending on which features you are using, there could be quite a number of jars that you need to add. One option would for example would be to extract the jars in the jBPM runtime zip that is part of the jBPM downloads into your WEB-INF/lib.
If you use Maven, you would be able to automatically derive all required jars.
Kris
I am a newbie to OSGi, started using felix. I am at present well versed with the concept of bundles, service etc. I have a requirement where I can embed Felix into Tomcat, I tried googling the same but was unable to find a relevant solution for my purpose.
What I exactly need is..
Till now I used to deploy my web app bundles into embedded http jetty service/PAX web.. installed inside Felix, but now I want to put Felix into Apache Tomcat/any other application server, so that whenever my tomcat starts up I need my felix instance up and running, and at the same time should be able to deploy/install/start my bundles through felix.
Any kind of help would be greatly appreciated.
You might want to consider the Apache Sling Launchpad subproject. This creates a WAR file which can be deployed into any servlet container and which launches the Apache Felix framework as the OSGi framework.
See also the Sling Launchpad and Embedding Sling for more information.