Automatically restructuring programs for the Web

The construction of interactive server-side Web applications differs substantially from the construction of traditional interactive programs. In contrast, existing Web programming paradigms force programmers to save and restore control state between user interactions. We present an automated transformation that converts traditional interactive programs into standard CGI programs. This enables reuse of existing software development methodologies. Furthermore, an adaptation of existing programming environments supports the development of Web programs. 1 Designing Web Programs The need for generating Web information on demand is obvious. One page may need the current time and date; another page may include results from a database query; a third page may display the current status of the server. Since such programs compute small amounts of information and produce not much more than a single Web page, people call them scripts. Following a long-standing tradition in computing, Web scripting has grown up. These scripts have now turned into serious, maintained programs that sometimes represent the raison d’être of a commercial establishment. Consumers can find on-line stores, e-mail clients, interactive games, and more implemented with a Web interface. In other words, instead of writing Web scripts, programmers now design, implement, and maintain interactive Web programs with complex and multi-layered interface protocols. Thus, all the usual software engineering concerns about evolving maintainable code to match growing requirement specifications apply