The book dedicates the majority of each chapter to more general concerns than just interfacing with the system in the chapter’s title. So Chapter 2—”Buy It On Amazon”—spends most of its time exploring XML-RPC and REST approaches and building tools to work with those different styles of interface. Similarly the next chapter spends most of its time introducing WSDL, XML Schema and SOAP before showing how they can be used with Microsoft Live Search.

In fact, that chapter may be one of the best introductions I’ve seen for developers who need to quickly grasp the basics of WSDL and SOAP, a topic that can far too easily get bogged down in complexity that isn’t needed for basic usage. With the WS-* stack quickly and for good reason going out of fashion hopefully most developers won’t have to spend much time with it, but a simple overview is still very handy.

I was intrigued to see the final chapter diving into use of RDF with the RAP toolkit. Like the SOAP section, this managed to boil the basics of RDF down very well and should help most moderately experienced PHP developers to get up to speed quickly.

Aside from a closing section on race conditions, not much time is given to handling interruptions in service from third-party services and in a book focussed on mashups that’s disappointing, particularly as the number of services, and so the range of fallback options, is increasing. Some of the examples are likely to fail if services time out and it would be good to spend some time on helping developers avoid that.

Reading the book as someone who has mostly left the PHP fold for pastures new was a reminder of how easy tools like hpricot make life for screen scrapers, but also that good structure can emerge in PHP code and that the SOAP tools are actually quite good for simple uses. The book is unlikely to appeal to those who don’t do much work with PHP, but if you’re a PHP developer and want to dive into mashups and web services for the first time, it’s worth a look.

Disclaimer: I was sent a copy of this book for review by the publisher, and offered another in return for a timely review. You can find it at packt, amazon US, amazon UK and all sorts of other places.