Scripting and Integration

In finance, industry and government, batch information processing was the first widely adopted strategy for applying the computer to problems of general interest.

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And batch processing is still important. Every major bank, airline, manufacturer and government agency would stop without it.

Batch processing is one way for a computer to do its work. Once a batch process starts, it continues without intervention until all data is processed. Batch processing does not imply what the work will be or what kind of computer will do the work. Jim Manias, vice president of sales and marketing for software company Advanced System Concepts Inc. (www.advsyscon.com), Morristown, N.J., describes the situation: “Batch processing can be applied to anything. Traditionally, batch processes ran at definite time intervals: every other week or every hour. But now, it’s common to run them based on events, such as running one batch process based on the completion of another batch process.”

In most large organizations, batch processing occurs for multiple reasons on multiple computer systems that are to some extent incompatible. “Different applications tend to be inward‑focused rather than outward‑focused,” says Manias. “They know about themselves and have some kind of internal scheduling, but they don’t know about each other.”

Rewriting the script

In terms of batch processing, the problem is to coordinate the order and timing of job execution and to exchange data between the systems to integrate them. The solution is often described as providing some type of “glue” to bind the individual systems together. The alternatives come down to “build or buy”: build a custom‑scripted solution or buy a commercial off‑the‑shelf (COTS) middleware solution.

“Flexibility is always the trade‑off,” says Manias. “If you want something highly customized, then you have to build it yourself. But, if you can work within the framework of a pre‑packaged solution, you have to ask, ‘Do I want to script all these things?’ “

In an enterprise with strong scripters, the choice is not easy. A number of factors are involved, time and money principal among them. Standard pitfalls must be avoided, such as the tendency to see each new COTS offering as an unalloyed cure‑all, the aversion to a COTS solution based on a “not‑invented‑here” complex, and the failure to appreciate all the effects that any solution will have on the overall enterprise.

The advent of scripting as distinct from programming, with the attendant mass of strongly advocated scripting languages—Perl, JavaScript, VB, Python, Tcl, PHP, Ruby—can confuse rather than clarify the situation. The point of scripting is to move the programmer away from the system and closer to the enterprise‑level problem that needs solving—in this case, integration. A scripting language is a “very high-level language,” an advantage in prototyping, rapid development, and in an enterprise that makes use of many kinds of systems, for a powerful, flexible, custom‑programming “glue.”

Custom‑scripted and COTS solutions are alternatives, but they are not mutually exclusive. A good COTS solution will leave room for scripting to provide customization. Markup language will also be part of the integration project. HyperText Markup Language (HTML) will control how text and graphics are displayed in a Web browser. Extensible Markup Language (XML) will serve as a generalized data type that can be easily exchanged between different systems. As Manias explains, “The markup language makes it easy for our data objects to be imported, exported and reused.”

Batch processing came first, but it is not a static approach to computing. New technical options and marketplace forces are catalyzing novel ideas concerning batch processing—not to replace it, but to bring it out into the enterprise.

Marty Weil, martyweil@charter.net, is a freelance writer.

Advanced System Concepts Inc.
www.advsyscon.com

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