Since its release in 2004, PHP 5 has evolved to become stable enough for serious consideration in use in a production environment. Along the way, PHP 5 has seen more than a handful of tweaks and changes, especially in its overhauled support for XML and XML web services. Now that it is a stable, it is fitting that there be a reference on all things PHP and XML.
Enter Pro PHP XML and Web Services, which aims to be "your single source of reference when using XML in PHP". Alas, the first thing that struck me about this book when it arrived on my door step was its Bible like size.
The author, Robert Richards, was one of the developers of PHP 4's DOM XML extension and a contributor in PHP 5's new DOM extension. From the outset, he makes it clear that he will leave no stone unturned and explain XML, its technologies and implementation in PHP in detail.
He then goes on to showcase the XML parsers in PHP 5, both the native ones and the PEAR XML parser. He devotes an entire chapter to each; explaining fully their use and features (or lack thereof) with examples in PHP. He also demonstrates how to parse more complex documents that include namespaces and how to extract the data you need through xPath. He does not stop there, however, as he goes on to explain the pros and cons of each parser and their corresponding memory footprints and shows how to effectively parse and process XML documents by combining the technologies at your disposal.
The main focus of the book is XML web services which Robert then goes on to explore. Again, devoting a chapter to each, he starts with one of the most widely used XML web services, RSS and Atom, and then feeds into REST, WDDX, XML-RPC, SOAP and UDDI. The detailed explanations of the appropriate specifications are second to none. For each technology, he demonstrates through code examples how to create and consume web services.
There is one more little treat that this book has to offer however--the chapter on XML Security. It is rare to encounter these two words in close proximity, but here again we see an entire chapter devoted to the subject, demonstrating the use of PHP's native tools to encrypt data within XML documents and the use of application independent XML signatures to encrypt and decrypt data inside documents.
Its hard to find fault in this book, but my only reservations concern the chapters on XML Security and XSLT, which seem a little out on the limb. Robert Richards has pulled out all the stops to create an intuitive and detailed reference, a book which could easily take the place on your bookshelf as the single point of reference for PHP and XML.
Pro PHP, XML and Web Services from Apress