Developing Software in a service-oriented world

Abstract: The software development community is once again at an interesting inflection point. Distributed and interconnected systems have become the norm for new development efforts to the extent that the word "application " itself might have to be redefined. Independent variability and evolution of the interconnected components are enabled through loosely coupled solutions, such as Service-oriented Architectures (SOA). At the same time, Model-driven Architectures (MDA) aim to simplify development by abstracting and automating large portions of the coding effort. This leaves us wondering what it will mean to develop in a service-oriented world. Will business analysts wire together components in visual tools? Will developers program using meta-meta-models and domain specific languages? What new types of programming paradigms will developers use? How can we get ready? 1 Right-Click, Make Web Service There is no doubt that the advent of Web services standards has made previously tedious programming tasks significantly easier and more efficient. For example, I recently developed a simple application that retrieves the Amazon sales rank of my book and e-mails it to my mobile phone. Naturally, this application needs to retrieve data from an external organization over the Internet. Still, developing the application could not have been easier. I pointed my IDE to the WSDL provided by Amazon and without much ado the tool generated a client proxy class for me. I added a few lines of code, and my application was up and running. Not only is this application fully buzzword compliant – I used Web Services, XML, WSDL, SOAP, you name it-- but it actually does something useful (bolster an author's ego). Exposing existing functions as Web services has become similarly simple. Most development tools are not far from allowing the developer to highlight a method and to select "Make Web Service " from the pop-up menu. It would be almost trivial to expose an enhanced version of my little program as a public Web service, for example allowing other users to submit a list of ISBNs and an e-mail address to receive periodic sales rank updates via e-mail