A History: Integration solutions, from ESB's to Camel + Karaf!

This was based largely from a response I made to an OSGi question on stackoverflow.com. I thought it would be good to share it with you folks.

First and foremost, ESB's were a really good idea 8 years ago when they were proposed. And, they solved an important problem: how do you define a business problem in a way that those pesky coders will understand? The goal was to develop a system that would allow a business person to create a software solution with little or no pesky developer interaction needed that would suck up money better spent on management bonuses.

To answer this the good folks at many organizations came up with JBI, BPMN and a host of other solutions that let business folks model the business processes they wanted to "digitize". But really, they were all flawed at a very critical level: they addressed business issues, but not integration issues. As such, many of these implementations were unsuccessful unless done by some high-priced consultant, and even then your prospects were sketchy.

At the same time, some really smart folks in the very late 90's published a book called "Enterprise Integration Patterns" which identified over 60 design patterns used to solve common integration problems. Many of the folks performing ESB stuff realized that their problem wasn't one of business modelling. Rather the problem was how to integrate thier existing applications. To help solve this James Strachan and some really smart guys started the Apache Software Foundation Project "Camel".

Camel is a good implementation of the basic Enterprise Integration Patterns in addition to a huge number of components designed to allow folks like you and I to hook stuff together.

So, if you think of your business process as simply a need to send data from one application to another to another, with the appropriate data transformations between, then Camel (riding in a container such as Karaf) is your answer. In fact, there is a large movement towards replacing ESB's with Karaf + Camel.

Now, what if you want to base the "route" (a specified series of application endpoints you want to send data thorugh) off of a set of configurable rules in a database? Well, Camel can do that too! There's an endpoint for that!