Events notification (presentation) using WSO2 technologies

The post is about creating a dashboard to display event notifications using few of WSO2 Technologies.

Requirement : Capture events from an event sender and display it in a dashboard

Used Technologies : WSO2 Enterprise Service Bus, WSO2 Application Server, WSO2 Gadget Server

Architecture : In brief, events are generated randomly, ESB will act as an event sink, and it will publish the events to the subscribed parties (to a service deployed in WSO2 AS). There is a gadget deployed in WSO2 Gadget Server where it will poll the received events from the service periodically.



At the ESB end we will have to set up the event sink as following,

Then you need to create a topic in the ESB and subscribe the created service. Steps in doing so is documented here

The Service

A very simple service to accumulate the events (this is not at all production grade, who whats to keep all the event in memory 😉 )

The Client

Its too long to post, you can check it at

You can run the client like “ant trafficevent -Dtrpurl=http://localhost:8280

The Gadget
In Action


A simple tool for all sorts of diagrams

Recently I had to draw some solutions architecture diagrams, and searched some good tools for diagramming. I have used Visio, long time back, nice tool, but I wanted to stick to Ubuntu and didn’t like switching back and forth. I tried Dia and Umbrello but they couldn’t really content me.

What I really digged in a nice architecture diagram is mainly its simplicity (Simple way the complex scenarios are drawn), fresh, elegant and rich look, as for a diagramming tool, it has to be simple (don’t have to be an artist) and flexible (should be able to draw new shapes if needed etc)

Sometime back I have used “Pencil” to draw some wire frames for a web app I was creating, I really liked the tool, and the final look and feel of the diagram it created. Non of the advance diagramming tools generated such a rich look and feel. So I thought of creating few custom stencils to graduate Pencil from a wire-framing tool to a full fledged multipurpose diagramming tool.

I created Three stencils to draw most of the enterprise architecture diagrams, following diagram is a sample solutions architecture diagrams I created using Pencil, and the custom stencils I created.

The stencils I have created are,

So if you are interested go ahead download the stencils, and install them in “Pencil” and if you still haven’t tried “Pencil”, I highly recommend it.