a book that tells you how to write Moodle code. Now it is finally here. Does it live up to expectations?
Yes, I think it does. The authors, Mike Churchward and Jonathan Moore, are two experienced Moodle developers (they both work for Canadian Moodle Partner Remote Learner) so they can write authoritatively on the subject.
One issue with a book like this is that the examples given are, necessarily, fairly basic. To illustrate key techniques and ideas, a book must explain using the simplest example that makes the point. The question is, when you come to solving real problems, will the techniques you have learned expand to cope? Well, this is where the experience of the authors counts. They are telling you the right way to do things that works for real applications, even if they are only using simple examples to illustrate them.
The book does a thorough job of covering just about every type of Moodle plugin there is. Of course, some plugin types get more space than others, with the two most important, blocks and activity modules getting the most space. Therefore, some other plugin types, like question types, and gradebook plugins, are covered rather briefly. Between the chapters on the different types of plugins are chapters on more general topics like security, accessing the database, and so on.
Anyone who has had code reviewed by me will know that I get really pedantic when I review something. As I was reading the book I made a list of minor errors, or points where I disagreed with the authors. From the 300 pages of the book, I only found 22 things to put on my list, and none of them are interesting enough to mention here. (I did send the list to Jonathan.) So, I think this book has a very high standard of accuracy.
This book does assume you already know how to program in PHP, and write HTML and CSS. I think that was the right decision. There are plenty of excellent books out there that will teach you to write general web application in PHP, and it would be silly to duplicate those in a book that is uniquely about writing code for Moodle.
It is unfortunate timing that this book was released only a few months before Moodle 2.0. Moodle 2.0 does change quite a lot of the rules for how to do Moodle development, and so a lot of the details in the book will soon be out of date. However, don't let that stop you from getting this book. We have just talked about how this book helps you make the jump from being a general PHP developer to being specifically a Moodle (1.9) developer. Well, from there to being a Moodle 2.0 developer is just another small step. You won't be wasting much time if you learn about Moodle 1.9 first, and anyway, some people will still be running Moodle 1.9 for some time to come, and it will be a while before there is a book about Moodle 2.0 development on sale.
This should go without saying, but programming is an activity that you actually need to do to understand. You won't become an expert Moodle programmer just be reading a book. You will become a Moodle programmer by actually trying to write Moodle code, and learning from your own mistakes, and from the code other people have written in the past. What a book like this will do for you is that it will help you avoid a lot of the really basic mistakes, and it will set you off on the right path. So it will make your own learning-by-doing much more efficient, but I cannot replace the doing. Also, I would like to point out that while this is the only book about Moodle development, it is certainly not the only resource to help you learn Moodle development. If you are interested in this book, you should also look at the Developer documentation on Moodle Docs and the Introduction to Moodle Programming course on http://dev.moodle.org/.
Overall, if you want to learn Moodle development, this is a good book to help you attain your goal. Sure, you can get a lot of the information for free online, but in this book the authors set it out clearly and in a logical order. The information in this book has been written by expert Moodle developers and then carefully reviewed, so you can read the book without being on your guard for misinformation. You would have to be more careful just using the information Google finds for you online. So, as I say, this book lives up to expectations. If you want a book on Moodle development, get this one, and don't worry too much about Moodle 2.0 making it out-of-date.