BVS Tools' Alternative to CGIDEV2

Published: May 23, 2006

by Alex Woodie

Brad Stone may be better known as an author and trainer, but his company, BVS Tools, recently shipped a new development tool called eRPG SDK designed to help OS/400 shops put dynamic iSeries data on the Web, without hard-coding XML or HTML into RPG applications. The tool is largely based on programming techniques and samples Stone has included in his line of successful books, and is positioned as easier-to-use and support option to CGIDEV2, a popular open-source toolkit for iSeries Web development.

In the iSeries world, there is no shortage of products and techniques for retrofitting legacy applications with the capability to write Web pages instead of the 5250 green screens they were originally designed to generate. Screen scrapers, which were never an elegant solution, have fallen out of favor, while IBM's CGIDEV2 has found its second wind, and a new breed of hybrid RPG/HTML editors have gained popularity.

Now Stone is throwing his take on iSeries Web development into the mix. eRPG SDK works a little bit differently than the hybrid RPG-HTML editors, and uses CGI techniques. As opposed to coding HTML directly into the source code of an application written in RPG (or COBOL or any other ILE language, despite the use of "RPG" in the product's name), eRPG SDK requires developers to insert variables into the source code that call functions in a template, which in turn generate the required HTML or XML and then pass it to the HTTP server (powered by Apache). In this way, the business logic and presentation layers are separated, giving the new iSeries Web app the best chance at a decent interface.

Stone has borrowed from his books and expert knowledge of iSeries Web programming with this tool, and incorporated a variety of service functions and subprocedures, including date, string, message, IFS, library list, and standard HTTP wrappers, into the toolkit. Additional source code examples in this tool are: looping applications that write to standard output (a Web browser) or to an IFS stream file; input applications for passing data from Web forms to the ILE application; data programs that show how to use OS/400 library list functions to display data, such as a purchase order, in a Web browser; AJAX (Asynchronous JavaScript and XML) samples; and standard e-commerce Web sites using shopping carts.

HTML isn't the only output generated by eRPG SDK. The templates can be customized to generate e-mail messages, or even XML-based Web services, complete with SOAP messages for application-to-application connectivity.

If you are an adamant do-it-yourself programmer, you'd probably be more apt to follow Stone's lead, borrow from his samples, and purchase one of his books. What's nice about eRPG SDK is Stone has bundled his knowledge into a shrink-wrapped product that sets a foundation for your iSeries Web project and gives you a head start on the custom programming it will involve. This is useful for jack-of-all-trades types and those starting to learn the ins and outs of iSeries Web programming.

Stone says eRPG SDK, which was first released in September 2005, picks up where CGIDEV2 leaves off, in terms of usability and performance. "I created this tool because, although CGIDEV2 worked great, I didn't feel it was as intuitive as it could be," he writes in an e-mail. " So I put together eRPG SDK so that it would be faster, more intuitive, and more easily updated, since it is very pure ILE which makes future updates to the product very easy."

eRPG SDK also includes facilities for creating and working with cookies, and supports error reporting through the HTTP server's job logs. This tool includes a pre-configured instance of the Apache Web server, so users can get up and running, and generating their first Web pages, soon after loading the software, Stone says.

At $599 per server and $299.50 for each additional LPAR, eRPG SDK version 2.0 is very affordable compared to the hybrid RPG-HTML editors. Weighed against the cost of CGIDEV2 (zero dollars), the price looks steep, until you consider the support aspect. For more information, go to www.erpgsdk.com.