KWATT: a toolkit for automatic web service generation

The Earth Science community is tackling computational problems that tax our largest computational resources. The size of the resulting datasets has been increasing almost exponentially over the last decade. Analysis of this data requires a cross-section of tools to extract useful information. Several international teams are working in concert to generate and analyze this data. A growing number of tools operate through Web services, which are the currently accepted mechanism through which users initiate tasks on one computer and execute them at some remote location. This paper presents a new tool, KWATT, a C++ application that generates web services from Tcl, Python, and Ruby scripts automatically, with minimal user intervention. KWATT parses the scripts and extracts information about procedures and user-defined control statements, embedded as comments. KWATT creates all necessary C++ wrappers, along with the code stubs required by gSOAP, a C++ interface to the SOAP protocol. Initially conceived to translate VTK front-end Tcl scripts into Web Services, the architecture is sufficiently general to accommodate a wide range of input languages. We demonstrate this capability with Tcl, Python and Ruby. Clients receive images through a dedicated socket for efficiency.