PHP3: Programming Browser-Based Applications with PHP

David Medinets's principal task in PHP3: Programming Browser-Based Applications is to find common ground for a discussion of PHP3, the database-interfacing module for the Apache Web server. Unfortunately, his task is subverted by PHP3's complexity.

In principle, PHP3's Perl-like script slides into HTML. When accessed by a browser, the code is interpreted by the Apache server, building a Web page out of data pulled from an SQL database through Apache's PHP3 module. The centrality of PHP3 in linking the user to the database is clear, but the stability of a uniform PHP3 implementation in an intrinsically heterogeneous Linux/Unix environment is so problematic as to be prohibitive.

To be fair, Medinets's PHP3: Programming Browser-Based Applications is a thoughtfully constructed book, but it sends mixed signals about whether it will enter the fray of PHP3 module support. Medinets's 20-page line-by-line description of building PHP3 begins with guidelines on how to make a new gcc compiler. Safe to ignore? Maybe not, because his Apache server-build instructions should be followed verbatim. A clean build and test on a generic Linux distribution is a multi-day effort because essential environment variables aren't documented--neither by Medinets nor by the PHP3 development team. Dynamical loading of the PHP3 module (the modern standard for module handling) is itself a subject of strongly worded statements in the newsgroups. Medinets has no comment on this show-stopping issue.

The book consists of didactic chapters on data manipulation, regular expressions, basic object-orientation, the CGI interface, and XML, all of which get interspersed with task-oriented interludes on connecting to databases, maintaining lists, creating HTML modules, and managing concurrent access. Over 100 pages of appendices provide SQL and PHP function references and Internet resources.

But the PHP3 development team must stabilize its interfaces before any single-source tract will suffice. Until then, readers must make personal commitments to read all available documentation. For the fearless few who venture into the PHP3 backcountry, Medinets offers an errata page at www.mtolive.com/phpbook to help with orientation. Active PHP3 mailing lists (www.php3.org) contain questions and answers, which are disparaging and hyperbolic but occasionally helpful.

The PHP3 developers have an outpost with a stable platform, and Medinets is safe at the outpost, but his smoke signals are too far away and the winds too variable for him to be of much help to us yet. --Peter Leopold