Best practices in web service style, data binding and validation for use in data-centric scientific applications

We provide a critical evaluation of the different Web Service styles and approaches to data-binding and validation for use in ‘data-centric’ scientific applications citing examples and recommendations based on our experiences. The current SOAP API’s for Java are examined, including the Java API for XML-based remote procedure calls (JAX-RPC) and Document style messaging. We assess the advantages and disadvantages of 'loose' verses 'tight' data binding and outline some best practices for WSDL development. For the most part, we recommend the use of the document/ wrapped style with a 100% XML schema compliant data-model that can be separated from the WSDL definitions. We found that this encouraged collaboration between the different partners involved in the data model design process and assured interoperability. This also leverages the advanced capabilities of XML schema for precisely constraining complex scientific data when compared to RPC and SOAP encoding styles. We further recommend the use of external data binding and validation frameworks which provide greater functionality when compared to those in-built within a SOAP engine. By adhering to these best practices, we identified important variations in client and experimental data requirements across different institutions involved with a typical e-Science project.