Last fall, Zend Technologies, Inc., and IBM jointly announced the availability of the PHP language on the System i. PHP is an open-source scripting language that developers can embed in HTML as an alternative way to build web applications. Zend for i5/OS is Zend's implementation of a PHP application development and control environment for the System i.

A Nibble on the Suite Parts

Zend for i5/OS consists of four products that jointly provide PHP capabilities on the System i. Zend Core and Zend Platform run with the Apache Web Server and operate under i5/OS and IBM's Portable Application Solutions Environment (PASE). Zend Studio and Zend Guard run on client workstations under Linux, Mac OS, or Windows.

Zend Core for i5/OS is an enhanced version of PHP with resources and capabilities specifically designed for i5/OS. It offers a tested and enhanced version of PHP that includes a complete installation wizard, database drivers for DB2/400 and MySql, and drivers and third-party libraries needed for other databases and platforms.

Zend Studio for i5/OS is an integrated development environment (IDE) for PHP applications. It includes a set of editing, debugging, analysis, optimization, and database tools to speed and simplify PHP development products. It also provides such features as nested code completion, syntax highlighting, a code editor, and System i Toolkit functions and templates.

Finally, Zend Guard is a security application that protects finished PHP applications from reverse-engineering, unauthorized customization, and unlicensed use and redistribution.

The Heart of the Matter

The most important component of the Zend suite for i5/OS is Zend Platform for i5/OS. Platform for i5/OS helps users in development and production environments manage and monitor PHP applications (Figure 1) and improve their performance. In many instances, Platform provides PHP application management and control similar to that which the System i traditionally enables for RPG applications. For example, Zend Platform helps system managers and other users keep an eye on web apps via the PHP Intelligence feature set — a central management console that offers multiple operational modes.

In the Event Triggers mode, Platform can help developers pinpoint the exact section or line of code within an application that contains an error or is causing poor performance. In addition, users can set up automated operator notifications of specific kinds of events the Intelligence mode should look for. Once users define a trigger event to the system, they can replicate these triggers to other servers in the cluster. If a trigger event occurs, Platform can send event data via e-mail or as an XML report to a URL so that the right people can access the information and resolve the problem. Users can configure the events by type, severity, and server location. Another option is to send event data via a Simple Network Management Protocol (SNMP) trap. Finally, because Platform is integrated with Zend Studio, messages can go directly to Studio so that if the problem requires a coding change, developers can make that change and distribute it.

Platform's Intelligence mode enables a developer to view events at any point in time or record them for future reference. In Intelligence mode, users can generate event reports to help developers investigate and fix problems. Platform also offers integrated Business Intelligence and Reporting Tools (BIRT) functions. BIRT is an Eclipse-based reporting system that lets users generate browser-based HTML reports.

These features are just the tip of the iceberg. In total, Platform for i5/OS lets users identify and repair problems without a great deal of PHP knowledge.

Performance Management

Zend Platform users can optimize and tune PHP application performance based on the application's use via several methods. These include code acceleration and optimization, dynamic content caching, file compression, and the Download Server.

The code-acceleration component performs a precompilation of PHP scripts, eliminating the need to parse scripts manually and optimizing the scripts to execute faster. To further increase server speed, the Dynamic Content Caching function reduces the number of times a server must run complex scripts, execute database queries, or call external web services. This function can retain cached versions of any URL.

File compression is another way that Platform increases information download speed and decreases the workload on a server. At any time, users can access the Acceleration Performance Tuning page of Platform to adjust performance-related settings. A plug-in, the Zend Download Server, deals with serving downloads such as videos, binary products, and other large files. Finally, a Job Queue Server streamlines offline PHP script processing by rerouting and delaying the execution of PHP scripts that aren't essential during user interaction with the web server.

The combination of features in Zend for i5/OS provides a stable and useful environment in which to write web applications for the System i using PHP. If PHP's versatility makes sense for your enterprise, Zend's solution can provide a solid foundation.

Erin Bradford is an assistant editor for System iNEWS.

John Ghrist is senior products editor for System iNEWS.

Solution Spotlight is a System iNEWS feature that provides more in-depth coverage for selected System i products. Selections are based on staff perception of the product as significant to the System i market. Source material for Solution Spotlights includes user manuals and other documentation provided by product vendors and is not the result of any product testing.