Adapting service interfaces when business processes evolve

Nowadays, there are many popular different notations of business process modeling, such as, e.g. BPMN [1], for a software analysis. Modeling of business processes at the conceptual level allows domain experts to cooperate in the analysis and to design the software. The whole business process model can be later translated to web services and executable BPEL [2] scripts which orchestrate all related parts together. Besides this automatization, it is necessary to define the structure of each data object in the business model. Web services usually communicate by exchanging XML documents [3]. Therefore, a software architect has to define also an XML schema of XML documents by an XML schema language, e.g. XML Schema [4]. In this paper, we present a method which derives and adapts optimal communication XML schemas for a given conceptual schema of a business process, complemented with a conceptual schema of exchanged data. We use a view on a part of a Platform Independent Model of a whole system as conceptual schema of exchanged data. We derive several XML schema documents from given inputs and choose the one which has minimal values for three metrics. The result of these three metrics is a measure of a quality of an XML schema document with respect to conceptual model of exchanged data and business rules applied on this document.