Summary

The SOA Suite speaks XML. Almost all files we create during the development of composite applications are XML documents. And the vast majority of data processed by those applications when in production is also XML. It is essential for SOA Suite developers—as well as architects and to some extent functional analysts and testers—to be aware of the primary XML concepts and technologies, such as namespaces and XSD as well as XPath and XSLT (see Appendix B for these last two).

The interfaces for services in the SOA Suite are typically specified in yet another XML document, based on WSDL. This chapter introduced the structure of the WSDL document, focusing first on the portType (the interface) that defines the operations and refers to the input and output parameters, whose structure is usually defined in associated XSD documents. The port element in the WSDL document specifies through which protocols (such as SOAP) and on which endpoint the service can be invoked. This element only needs to be defined upon deployment—and it may even be derived as a result of deployment.