An object-oriented approach to deploying highly configurable Web interfaces for the ATLAS experiment

The ATLAS Technical Coordination disposes of 17 Web systems to support its operation. These applications, whilst ranging from supporting the process of publishing scientific papers to monitoring radiation levels in the equipment at the cave, are constantly prone to changes in requirements due to the collaborative nature of the experiment and its management. In this context, a Web framework is proposed to unify the generation of the supporting interfaces. Fence assembles classes to build applications by making extensive use of JSON configuration files. It relies vastly on Glance, a technology that was set forth in 2003 to create an abstraction layer on top of the heterogeneous sources that store the technical coordination data. Once Glance maps out the database modeling, records can be referenced in the configuration files by wrapping unique identifiers around double enclosing brackets. The deployed content can be individually secured by attaching clearance attributes to their description thus ensuring that view/edit privileges are granted to eligible users only. The framework also provides tools for securely writing data to a database. Fully HTML5-compliant multi-step forms can be generated from their JSON description to assure that the submitted data observe a series of constraints. Input validation is carried out primarily on the server side but, following progressive enhancement guidelines, verification might also be performed on the client side by enabling specific markup data attributes which are then handed over to the jQuery validation plug-in. User monitoring is accomplished by thoroughly logging user requests along with any POST data. Documentation is built from the source code using the phpDocumentor tool and made readily available for developers online. Fence, therefore, speeds up the implementation of Web interfaces and reduces the response time to requirement changes by minimizing maintenance overhead and facilitating the comprehension of embedded rules and requirements.