Towards the Automatic Generation of Web GIS S. Di Martino, F. Ferrucci, L. Paolino, M. Sebillo, G. Vitiello, G. Avagliano University of Salerno - DMI Via Ponte Don Melillo, I-84084 Fisciano (SA), Italy 2nd line of address {sdimartino, fferrucci, lpaolino, msebillo, gvitiello}@unisa.it ABSTRACT The goal of disseminating, manipulating, and exploiting spatial knowledge over the Internet, has led to the development of Web applications, known as Web Geographic Information Systems (Web GIS). The growing need for tools that allow to rapidly develop Web GIS has motivated the extension of existing approaches for traditional web applications in the GIS domain. Among the different solutions, automatic generation tools deserve special attention thanks to the higher level of abstraction required during development. Indeed, developers have only to provide a visual specification of the target application that is automatically constructed by the tool. In the present paper, we propose an extension to the GIS context of the approach based on WebML, a high-level, formal visual language specifically conceived to design data-intensive Web applications. The proposal is motivated by the observation that Web GIS can be considered as a particular class of data-intensive Web applications and by the fact that WebML is gaining an increasing success for designing and developing traditional data- intensive web applications. In the paper, we describe the proposed extension of the visual formalism for modeling relevant interaction and navigation operations typical of Web GIS, and provide an example of its application within a prototype of the tool supporting the automatic generation of Web GIS. Categories and Subject Descriptors H.5.4 [Hypertext/Hypermedia]. D.2.2 [Design Tools and Techniques]Computer-aided software engineering (CASE) General Terms Design, Human Factors, Languages, Management. Keywords Web GIS, Design Models, Web Applications. 1. INTRODUCTION Recently, the increasing popularity of the Internet has led to the development of Web applications, known as Web GIS, intended for dissemination and manipulation of spatial knowledge in specific domains. In fact, Web GIS hold the potential to make geographic information available to a worldwide audience, allow Internet users to access GIS applications from their browsers without purchasing proprietary GIS software, and make it possible to add GIS features to a wide range of network-based applications in business, government, education, etc... [19]. With the increased time-to-market pressure, it is no longer possible to deal with low-level issues, and create Web GIS from scratch. Thus, there is a growing need for tools and methodologies that allow us to rapidly develop this kind of Web applications and to rapidly modify them to meet the ever-changing business needs [12]. Recently, in order to assist the classic developing methodology based on API, some frameworks have been developed by companies and research laboratories. To date, solutions like ArcIMS by ESRI [7], MapGuide by AUTODESK [1], WebMap by INTERGRAPH [11] and Mapacell [14] are becoming very popular because they enable users to develop and deploy WebGIS applications in a fast and easy way by simply selecting functionalities a user needs. However, the easiness of producing Web GIS applications is limited to generate interfaces where layouts are predefined. Further customization requires expertise in programming code. The outcome of this situation is a large quantity of WebGIS which are very similar both in form and functionalities, that is to say the easiness has been paid in terms of customizability. Other solutions allow developers to customize interfaces through WYSIWYG environments where widgets are selected from specialized palettes and then located into panels representing web pages [17], [21], [1]. This approach guarantees a flexible layout composition, but the customization of functionalities continues to be strictly deferred to the implementation level. As for traditional Web applications, many solutions are currently available meant to increase productivity and to support rapid development by allowing users to work at a higher level of abstraction. These can be grouped into two major approaches, one based on frameworks and the other based on automatic generation starting from visual specifications A Web framework is software that makes easy to build Web applications by abstracting frequent problems of Web development and providing shortcuts for common programming tasks (e.g. to display, and validate HTML forms, to convert user- submitted input into data structures that can be suitably manipulated, etc.), such as Django, Ruby on Rails, .Net, or J2EE. Automatic generation tools allow developers to go “up” one further level of abstraction. Indeed, they are based on a suitable visual language that is used to model the target application. Starting from the supplied visual specification, these tools are able to automatically generate the corresponding application (e.g. WebRatio, W2000, VisualWade). They differ in several aspects Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. ACMGIS’07, November 7–9, 2007, Seattle, Washington, USA. Copyright 2007 ACM 1-58113-000-0/00/0004…$5.00.