Book Review for "Drools Developers Cookbook RAW"

A Developer's Survey of the fast-moving Drools project

This review is for "Drools Developers Cookbook" from Packt. This book is currently available in 'RAW' format, which means it's not quite finished. The text is a little rough around the edges, and there are two chapters yet to be provided.

Do you work with Drools, the popular open source rule engine? If not, this is not the right book to get you started. There is no introductory material to get you started. But if you know Drools, this is your ticket straight to the current cutting edge! This book gives pointers and best practices for working with the latest and greatest features.

The first chapter gives you tips on working with rules. You'll see how to write rules in ways outside the usual, how to enable some diagnostic logging, and how to work with rules on timers and Calendars.

Chapter 2 deals with more 'bread and butter' Drools material, but this time not dealing with rules.

Chapters 3 and 4 cover Guvnor, the open source Business Rules Management System. Guvnor, a web app, allows you to author, categorize, and test your rules. This is how you can have business-analyst types write business logic instead of using programmers.

The fifth chapter is probably the most newbie-friendly chapter in the book, it deals with Complex Event Processing. CEP is a way of applying rules over windows of time, so you can express something like "Tell me if there are 100 online purchases in any half-hour period".

Chapters 6 and 7 deal with executing Drools remotely (mostly through 'Drools Server') and integrating Drools with other applications through Spring and Apache Camel. This is very handy-- after mastering Drools, developers sometimes wonder how to apply their newfound knowledge in a practical way. Here are some good ideas for solving that problem!

The two chapters that are not yet provided deal with Drools Planner (a tool for finding optimal solutions to problems like capacity balancing challenges) and jBPM5 (a re-hang of the popular jBPM Business Processing framework). These two will be very important, especially jBPM. I hope the author is putting a special emphasis on these.

All things considered, I find this book to be a good resource for Drools developers. As I've hinted, if you're new to Drools you probably need to start with something a little more basic. But if you're already into Drools, this is a quick way to get get a handle on state-of-the-art features.

The book can be found here.

Happy Drooling!