Building and Leveraging Web APIs

A number of useful services including Google, Amazon, EDGAR Online and Salesforce.com are now accessible on the internet through web APIs. The popularity of Service Oriented Architectures has led to similar techniques being used within enterprises to expose services on the intranet. As opposed to conceiving a SOA from the ground up, owners of data or application Silos can expose their offering as a service to the rest of the enterprise, allowing integrated applications to grow organically. Knowledge of a service that is available within the enterprise can trigger the creative thought needed to conceive of new ways to exploit those services to achieve greater productivity or new revenue streams.

 
We run into a number of examples of these in our interactions with our customers. Banks typically have a number of these services available enterprise wide – currency exchange rate information, credit ratings, financials, etc – which allow multiple applications to leverage this master data sources. We have seen configuration management systems used this way in IT firms, the data from which becomes fodder for risk analysis engines that determine patches that need to be applied to any system. The examples are many, but the underlying theme is the same. Applications and data are like Lego blocks. You can put together these blocks in a number of ways to solve increasing complex problems with great revenue potential. The only requirement is that these blocks have any interface to the outside world that lets them plug together.

 
This is nothing new. It has been done dozens of different ways in the past with Corba, DCOM etc. What might be new today is the fact that the current approach leverages a platform that is ubiquitous, language/development platform neutral and proven to be scalable. Utilizing basic building blocks like HTTP and XML(or JSON if you are one of those critical of XML for its overhead) you can quickly expose a service to the world. At Ipedo, we have come to embrace this approach to application development. Building views, either from scratch or by wrapping existing services, bringing together views to provide some new integrated functionality, and exposing this functionality again as view, is at the heart of the development methodology. The trick then is to make this system perform well, optimizing the functionality through methods such as pushing-down operations, caching and a host of other rule and cost based optimizations.

 
A standard portion of the Ipedo demos to customers includes examples of how these things I just described can be done. A bunch of examples involving public services like Google, Amazon, Salesforce are available, along with examples of how to build your own services. Check them out.