The quest for an OSGI friendly web framework

In a series of blog I am investigating and trying the available Java web-frameworks and how well they play in OSGI. I am spending exactly one day with each of them.

Background

NetXStudio is the application I have been working on the last few years. It allows Telecommunications Service Providers to collect performance data from Network components and resource, aggregate the data, and perform calculations and analysis on it. The main business goal is to act timely on congestion in the network.

It's an Eclipse RCP application with a server backend. The communication is through Eclipse CDO, which is a ORM solution on steroids. ( Besides mapping Java Objects to relational databases, it also works with non-relational DB's. On top CDO has an advanced 'audit' mode which allows to go back in time, and fetch an historical object graph, it's sort of ORM+GIT in one solution). Server communication happens through CDO communication protocol named Net4J. Additional communication, has been implemented through some HTTP calls, and a simple servlet implementation, which kicks of some processes. Here Eclipse Equinox HTTP bundles are used.

Both client and server are build with Eclipse, and grouped in OSGI bundles. On top, the Eclipse Equinox implementation provides additional functionality to deploy with products and features.

So what's next

So far so good, the application is in production and the customer is mostly happy. Mostly, because there is still lack of functionality, but also some impracticalities like not being web-based. 

As with many projects at some point there is time for reflection and planning for the future. In the case of NetXStudio, the idea is to bring the application to a wider audience by making it a modular platform with re-useable software components. Now with OSGI this is a breeze, applying OSGI Declarative Services allows true discovery of services, and service chaining and much more. With little effort most of the server side functionality was modularized and services can come and go. 

Thee is also a wish to make the UI fully web-based.

OSGI Ready web-framework 

So for a web-based UI, a web-framework is needed, with the capabilities to play nicely with OSGI.
Now, I don't really want to bother about the definition of "playin nicely", that would take up some time, I believe it's better to take 'them' for a spin and see what comes out.

The following solutions are explored:

1. Springframework and Spring-DM
2. Apache Karaf
3. PAX Web 
4. Equinox HTTP Services 
5. Gemini-Blueprint 
6. Vert.X (Added 17-120-2014)
7. ... (The list will grow over time I believe). 

Setting the scene

So, this is a rather big task I am committing myself to. A couple of rules to make the comparison fair and the exercise, fun and painless.

1. Get the framework up and running in one day.  
2. Should run on Eclipse Equinox. 
3. Have some interaction with my application bundles. (Serve objects to the web UI). 
4. Give some feedback on deployment and configuration.