The availability of WorldWideWeb browsers for many computer systems made it possible to develop platformindependent graphical user interfaces for commandlinedriven UNIX applications. We followed this trend with our development of a WWWinterface for the widely used GCG sequence analysis package and its derived systems like HUSAR. Using HTMLforms together with JavaScript on the client side and the Perl programming language on the server side, it is possible to achieve fast access and a high level of portability. Security requirements concerning the data flow via networks (e.g. Internet) are fulfilled by using Secure Socket Layer (SSL) encrypted HTTP data streams.
Instead of creating individual interfaces for each application, we decided to employ metadata. This enables the administrator to add new applications by simply writing a new metadata file containing the applicationspecific configurations. Additionally, this strategy results in a common graphical user interface for all applications.
The current W2H implementation comprises
At the moment W2H is mostly adapted to the GCG system but nonGCG commandline applications can be incorporated by using the metadata mechanism of W2H. W2H can be adopted to any other commandline driven system with only minor modifications.
We are currently extending the metadata mechanism of W2H, not only to describe interfaces to individual applications but also to complete tasks. In this context a task is understood to be a chain or even a network of applications together with its data flow. To achieve this, a mechanism is needed which describes the control and dataflow within one task. Metadata for such tasks will not only contain parameters of single applications, but also dependency and incompatibility rules for the inter relationship between different applications belonging to the same task.
W2H is freely available on the World Wide Web:
http://genome.dkfzheidelberg.de/w2h/ (Germany)
http://industry.ebi.ac.uk/w2h/ (UK)