Zend Puts 5250 Bridge Into Zend Platform for PHP
April 28, 2008 Timothy Prickett Morgan
While you might be interested in creating new PHP applications and running them on a System i or Power Systems machine with OS/400 V5R3, i5/OS V5R4, or i 6.1, the odds are that as an IBM midrange shop, you have lots of green screen applications sitting around that need to be enabled to run on the Web. There are plenty of ways to take 5250 applications to deploy them on the Web, from IBM as well as third-party tool suppliers, and now there is one more being supplied by Zend Technologies, the creator of the open source PHP programming language.
Zend has just rolled out Zend Platform for i5/OS V3.6, and as part of that package, the company has created what it is calling the 5250 Bridge–a set of middleware that runs atop the freebie Zend Core for i5/OS V2.5.2 PHP engine that converts 5250 data streams into Web pages using a mix of XML, PHP, and HTML technologies. Zend Core is the basic PHP runtime environment, and has over 10,000 installations so far in the OS/400 and i5/OS community; IBM has been paying for Zend to distributing licenses to OS/400 V5R3 and i5/OS V5R4 for free to anyone who wants it. Zend Platform is an extension of Zend Core that provides code acceleration, content caching, session clustering, job queues, SNMP integration, reporting, output compression, Java and 5250 bridges, and other management features that a production PHP application environment needs. Zend Platform is not free, and as we reported a few weeks ago, IBM and Zend have radically raised the price of Zend Platform licenses and support to reflect the additional value of the 5250 Bridge and other features and to reflect the fact that Zend does not do the tiered software pricing that is commonly used on OS/400, i5/OS, and i platforms. Unfortunately, IBM and Zend changed the prices before announcing the 5250 Bridge and other enhancements and did nothing to explain any of this in IBM’s announcement letters, which were just a list of feature codes and old and new prices. IT Jungle was, in fact, the only place where someone actually took apart the price changes and figured out what they were. You can see those price changes in this table.
The 5250 Bridge software that is part of the updated Zend Platform that was announced recently is functionally similar to other approaches available on the market, but has a PHP twist to it as you might expect. Here’s how it works, according to Zend. You create a PHP application and use the 5250 Bridge to link back into green-screen applications. PHP begins interacting with the green screen program by sending a start session request to that program through the bridge, and the bridge watches and sees that the session indeed starts with the application. The bridge then sends 5250 screen information in an XML format to the PHP application–format name, input and output fields, current cursor position, and such–and then the input values can be entered into a PHP program or sent out in HTML format to await user input in the application. This is what it looks like, conceptually:
So here’s how a normal 5250 green-screen looks like before it goes over the PHP 5250 Bridge:
And here is how it might be rendered after it is recoded using PHP and turned it into a Web application:
Zend says that the 5250 Bridge only invokes so-called batch processing on the iSeries, System i, and Power Systems and does not require what IBM used to call 5250 interactive processing. That means you do not have to pay the green-screen software tax to use this tool, much as other tools (including IBM’s own WebFacing tool and others from third parties on the market) do not have to pay the tax by requiring the activation of interactive processing capacity. Zend also says that the 5250 Bridge does not require display file source code and works directly on RPG and COBOL objects running on the system.
In addition to announcing Zend Platform V3.6 for i5/OS, the company announced Zend Core V2.5.2 for i5/OS, which is a prerequisite for the Platform and the 5250 Bridge code; this new core product has an updated PHP engine, improved PHP script performance, and the ability to install on an OS/400 V5R3, i5/OS V5R4, or i 6.1 server from a Windows workstation or server. Zend also announced its plans to ship Zend Studio for Eclipse i5/OS Edition, the companion development tool that is compatible with IBM’s Rational tools and Zend Studio Eclipse 3.4; this i5/OS-friendly version of Zend Studio will ship in the third quarter. And finally, Zend announced implementation services for all of its tools called the JumpStart for i5/OS Service, which does a proof of concept using PHP on an existing subset of green-screen code to show that all of this stuff works.